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Piccirillo G, Moscucci F, Mezzadri M, Caltabiano C, Cisaria G, Vizza G, De Santis V, Giuffrè M, Stefano S, Scinicariello C, Carnovale M, Corrao A, Lospinuso I, Sciomer S, Rossi P. Artificial Intelligence Applied to Electrical and Non-Invasive Hemodynamic Markers in Elderly Decompensated Chronic Heart Failure Patients. Biomedicines 2024; 12:716. [PMID: 38672072 PMCID: PMC11048014 DOI: 10.3390/biomedicines12040716] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2024] [Revised: 03/16/2024] [Accepted: 03/18/2024] [Indexed: 04/28/2024] Open
Abstract
OBJECTIVES The first aim of this study was to assess the predictive power of Tend interval (Te) and non-invasive hemodynamic markers, based on bioimpedance in decompensated chronic heart failure (CHF). The second one was to verify the possible differences in repolarization and hemodynamic data between CHF patients grouped by level of left ventricular ejection fraction (LVEF). Finally, we wanted to check if repolarization and hemodynamic data changed with clinical improvement or worsening in CHF patients. METHODS Two hundred and forty-three decompensated CHF patients were studied by 5 min ECG recordings to determine the mean and standard deviation (TeSD) of Te (first study). In a subgroup of 129 patients (second study), non-invasive hemodynamic and repolarization data were recorded for further evaluation. RESULTS Total in-hospital and cardiovascular mortality rates were respectively 19 and 9%. Te was higher in the deceased than in surviving subjects (Te: 120 ± 28 vs. 100 ± 25 ms) and multivariable logistic regression analysis reported that Te was related to an increase of total (χ2: 35.45, odds ratio: 1.03, 95% confidence limit: 1.02-1.05, p < 0.001) and cardiovascular mortality (χ2: 32.58, odds ratio: 1.04, 95% confidence limit: 1.02-1.06, p < 0.001). Subjects with heart failure with reduced ejection fraction (HFrEF) reported higher levels of repolarization and lower non-invasive systolic hemodynamic data in comparison to those with preserved ejection fraction (HFpEF). In the subgroup, patients with the NT-proBNP reduction after therapy showed a lower rate of Te, heart rate, blood pressures, contractility index, and left ventricular ejection time in comparison with the patients without NT-proBNP reduction. CONCLUSION Electrical signals from ECG and bioimpedance were capable of monitoring the patients with advanced decompensated CHF. These simple, inexpensive, non-invasive, easily repeatable, and transmissible markers could represent a tool to remotely monitor and to intercept the possible worsening of these patients early by machine learning and artificial intelligence tools.
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Affiliation(s)
- Gianfranco Piccirillo
- Department of Internal and Clinical Medicine, Anesthesiology and Cardiovascular Sciences, Policlinico Umberto I, “Sapienza” University of Rome, 00185 Rome, Italy; (G.P.); (M.M.); (C.C.); (G.C.); (G.V.); (V.D.S.); (M.G.); (S.S.); (C.S.); (M.C.); (A.C.); (S.S.)
| | - Federica Moscucci
- Department of Internal Medicine and Medical Specialties, Policlinico Umberto I, Viale del Policlinico, 155, 00161 Rome, Italy;
| | - Martina Mezzadri
- Department of Internal and Clinical Medicine, Anesthesiology and Cardiovascular Sciences, Policlinico Umberto I, “Sapienza” University of Rome, 00185 Rome, Italy; (G.P.); (M.M.); (C.C.); (G.C.); (G.V.); (V.D.S.); (M.G.); (S.S.); (C.S.); (M.C.); (A.C.); (S.S.)
| | - Cristina Caltabiano
- Department of Internal and Clinical Medicine, Anesthesiology and Cardiovascular Sciences, Policlinico Umberto I, “Sapienza” University of Rome, 00185 Rome, Italy; (G.P.); (M.M.); (C.C.); (G.C.); (G.V.); (V.D.S.); (M.G.); (S.S.); (C.S.); (M.C.); (A.C.); (S.S.)
| | - Giovanni Cisaria
- Department of Internal and Clinical Medicine, Anesthesiology and Cardiovascular Sciences, Policlinico Umberto I, “Sapienza” University of Rome, 00185 Rome, Italy; (G.P.); (M.M.); (C.C.); (G.C.); (G.V.); (V.D.S.); (M.G.); (S.S.); (C.S.); (M.C.); (A.C.); (S.S.)
| | - Guendalina Vizza
- Department of Internal and Clinical Medicine, Anesthesiology and Cardiovascular Sciences, Policlinico Umberto I, “Sapienza” University of Rome, 00185 Rome, Italy; (G.P.); (M.M.); (C.C.); (G.C.); (G.V.); (V.D.S.); (M.G.); (S.S.); (C.S.); (M.C.); (A.C.); (S.S.)
| | - Valerio De Santis
- Department of Internal and Clinical Medicine, Anesthesiology and Cardiovascular Sciences, Policlinico Umberto I, “Sapienza” University of Rome, 00185 Rome, Italy; (G.P.); (M.M.); (C.C.); (G.C.); (G.V.); (V.D.S.); (M.G.); (S.S.); (C.S.); (M.C.); (A.C.); (S.S.)
| | - Marco Giuffrè
- Department of Internal and Clinical Medicine, Anesthesiology and Cardiovascular Sciences, Policlinico Umberto I, “Sapienza” University of Rome, 00185 Rome, Italy; (G.P.); (M.M.); (C.C.); (G.C.); (G.V.); (V.D.S.); (M.G.); (S.S.); (C.S.); (M.C.); (A.C.); (S.S.)
| | - Sara Stefano
- Department of Internal and Clinical Medicine, Anesthesiology and Cardiovascular Sciences, Policlinico Umberto I, “Sapienza” University of Rome, 00185 Rome, Italy; (G.P.); (M.M.); (C.C.); (G.C.); (G.V.); (V.D.S.); (M.G.); (S.S.); (C.S.); (M.C.); (A.C.); (S.S.)
| | - Claudia Scinicariello
- Department of Internal and Clinical Medicine, Anesthesiology and Cardiovascular Sciences, Policlinico Umberto I, “Sapienza” University of Rome, 00185 Rome, Italy; (G.P.); (M.M.); (C.C.); (G.C.); (G.V.); (V.D.S.); (M.G.); (S.S.); (C.S.); (M.C.); (A.C.); (S.S.)
| | - Myriam Carnovale
- Department of Internal and Clinical Medicine, Anesthesiology and Cardiovascular Sciences, Policlinico Umberto I, “Sapienza” University of Rome, 00185 Rome, Italy; (G.P.); (M.M.); (C.C.); (G.C.); (G.V.); (V.D.S.); (M.G.); (S.S.); (C.S.); (M.C.); (A.C.); (S.S.)
| | - Andrea Corrao
- Department of Internal and Clinical Medicine, Anesthesiology and Cardiovascular Sciences, Policlinico Umberto I, “Sapienza” University of Rome, 00185 Rome, Italy; (G.P.); (M.M.); (C.C.); (G.C.); (G.V.); (V.D.S.); (M.G.); (S.S.); (C.S.); (M.C.); (A.C.); (S.S.)
| | - Ilaria Lospinuso
- Department of Internal Medicine and Medical Specialties, Policlinico Umberto I, Viale del Policlinico, 155, 00161 Rome, Italy;
| | - Susanna Sciomer
- Department of Internal and Clinical Medicine, Anesthesiology and Cardiovascular Sciences, Policlinico Umberto I, “Sapienza” University of Rome, 00185 Rome, Italy; (G.P.); (M.M.); (C.C.); (G.C.); (G.V.); (V.D.S.); (M.G.); (S.S.); (C.S.); (M.C.); (A.C.); (S.S.)
| | - Pietro Rossi
- Arrhythmology Unit, Fatebenefratelli Hospital, Isola Tiberina-Gemelli Isola, 00186 Rome, Italy;
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Bastos RF, Tuleski GL, Sousa MG. QT interval instability and QRS interval dispersion in healthy cats and cats with a hypertrophic cardiomyopathy phenotype. J Feline Med Surg 2023; 25:1098612X231151479. [PMID: 36745542 DOI: 10.1177/1098612x231151479] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVES Hypertrophic cardiomyopathy (HCM) is the most common heart disease in cats. Electrocardiographic (ECG) analysis can help with the diagnosis of HCM and also in the investigation of the secondary consequences of the disease. This study investigated ECG markers of QT interval variability (total instability [TI], short-term instability [STI], long-term instability [LTI], QT variance [QTv]), mean QT interval (QTa) and QT interval corrected for heart rate (QTac), as well as the duration (QRSd) and dispersion (QRSv) of the QRS interval in healthy cats and in those with HCM. METHODS Data were collected from 63 domestic cats: 40 in the control group and 23 in the HCM group. Fifty consecutive QT intervals were recorded for all cats and then QTa, QTac, QTv, TI, LTI and STI were calculated. QRSd and QRSv were also obtained for all animals. A Mann-Whitney U-test was used for group comparison. Receiver operating characteristic curves were plotted to evaluate the sensitivity and specificity of all markers for HCM. Logistic regression analysis was performed to assess the risks of cats having HCM, based on the studied indexes. RESULTS QTa (P <0.01), QTac (P <0.01), QRSd (P <0.01) and STI (P = 0.02) were higher in the HCM group. QTa >158.8 ms, QTac >27.4 ms and QRSd >0.045 s had an accuracy of 77.4%, 68.2% and 80.9%, respectively, in detecting HCM. Logistic regression showed that cats with QTa >158 ms, QTac >27.4 ms and QRSd >0.045 s had a 1.58-, 1,23- and 6.5-fold higher risk, respectively, of developing HCM. CONCLUSIONS AND RELEVANCE Cats with HCM had higher ventricular instability as assessed by STI and showed a prolongation of the QT and QRS intervals via the QTa, QTac and QRSd markers. These markers show potential as ancillary screening tools for identifying the presence of HCM.
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Affiliation(s)
- Rodrigo Franco Bastos
- Laboratory of Comparative Cardiology, Department of Veterinary Medicine, Federal University of Paraná (UFPR), Curitiba, Brazil
| | - Giovana Lr Tuleski
- Laboratory of Comparative Cardiology, Department of Veterinary Medicine, Federal University of Paraná (UFPR), Curitiba, Brazil
| | - Marlos Gonçalves Sousa
- Laboratory of Comparative Cardiology, Department of Veterinary Medicine, Federal University of Paraná (UFPR), Curitiba, Brazil
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Vila BDCP, Vanhoni MS, Sousa MG. QT interval instability and variability in dogs with naturally-occurring hypercortisolism. Vet Res Commun 2023; 47:121-130. [PMID: 35575953 DOI: 10.1007/s11259-022-09936-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Accepted: 05/04/2022] [Indexed: 01/27/2023]
Abstract
Hypercortisolism is one of the most common endocrine diseases in dogs. In humans, it is clearly associated with a higher risk of cardiovascular events, but studies in dogs are scarce. To investigate the arrhythmogenic risk of dogs with naturally-occurring hypercortisolism (NOHC), indices of variability and instability of the QT interval were retrospectively studied in 38 dogs with NOHC and prospectively studied in 12 healthy dogs: variance (QTv), total instability (TI), short-term (STI) and long-term (LTI), and mean (QTm). Except for QTm, all parameters studied were higher in the NOHC group than in the control group. In addition, STI and QTv showed moderate positive correlation with left ventricle wall thickness. The NOHC group was subdivided according to cortisol suppression pattern in the low-dose dexamethasone suppression test. All electrocardiographic indices of partial and absent suppression patterns were numerically higher than healthy dogs. QTv and TI were lower in the control group than in both NOHC subgroups. LTI and STI were lower in the CG than in the group with the partial suppression pattern. There was no statistical difference between sex groups in any of the electrocardiographic parameters studied. This result might indicate that the etiology of NOHC, and its consequent influence on hypothalamus-pituitary-adrenal axis could interfere on the heterogeneity of ventricular repolarization parameters in different ways, especially in the short-term and the long-term stability; however further studies are necessary to understand the role of cortisol on electrical instability in dogs.
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Affiliation(s)
- Beatriz de Carvalho Pato Vila
- Laboratory of Comparative Cardiology, Department of Veterinary Medicine, Federal University of Paraná (UFPR), Rua dos Funcionários, 1540, Curitiba, PR, 80035-050, Brazil.
| | - Marcela Sigolo Vanhoni
- Laboratory of Comparative Cardiology, Department of Veterinary Medicine, Federal University of Paraná (UFPR), Rua dos Funcionários, 1540, Curitiba, PR, 80035-050, Brazil
| | - Marlos Gonçalves Sousa
- Laboratory of Comparative Cardiology, Department of Veterinary Medicine, Federal University of Paraná (UFPR), Rua dos Funcionários, 1540, Curitiba, PR, 80035-050, Brazil
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Piccirillo G, Moscucci F, Corrao A, Carnovale M, Di Diego I, Lospinuso I, Caltabiano C, Mezzadri M, Rossi P, Magrì D. Noninvasive Hemodynamic Monitoring in Advanced Heart Failure Patients: New Approach for Target Treatments. Biomedicines 2022; 10:biomedicines10102407. [PMID: 36289669 PMCID: PMC9599112 DOI: 10.3390/biomedicines10102407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Revised: 09/21/2022] [Accepted: 09/21/2022] [Indexed: 11/24/2022] Open
Abstract
Using bio-impedance to deduce some hemodynamic parameters combined with some short-term ECG temporal dispersion intervals, and measuring myocardial depolarization, intraventricular conduction, and repolarization. A total of 65 in-hospital patients (M/F:35/30) were enrolled, 39 with HFrEF and 26 HFpEF, in New York Heart Association (NYHA) class IV. Stroke volume (SVI), cardiac indexes (CI), left ventricular ejection fraction (LVEFBIO), end diastolic volume (LV-EDV), and other systolic and diastolic parameters were noninvasively obtained at enrollment and at hospital discharge. At the same time, QR, QRS, QT, ST, Tpeak-Tend (Te) interval mean, and standard deviation (SD) from 5 min ECG recordings were obtained. At baseline, HFrEF patients reported significantly lower SVI (p < 0.05), CI (p < 0.05), and LVEF (p < 0.001) than HFpEF patients; moreover, HFrEF patients also showed increased LV-EDV (p < 0.05), QR, QRS, QT, ST, and Te means (p < 0.05) and standard deviations (p < 0.05) in comparison to HFpEF subjects. Multivariable logistic regression analysis reported a significant correlation between hospital mortality and Te mean (odds ratio: 1.03, 95% confidence limit: 1.01−1.06, p: 0.01). Fifty-seven percent of patients were considered responders to optimal medical therapy and, at discharge, they had significantly reduced NT-proBNP, (p < 0.001), heart rate (p < 0.05), and TeSD (p < 0.001). LVEF, obtained by transthoracic echocardiography, and LVEFBIO were significantly related (r: 0.781, p < 0.001), but these two parameters showed a low agreement limit. Noninvasive hemodynamic and ECG-derived parameters were useful to highlight the difference between HFrEF and HFpEF and between responders and nonresponders to the optimal medical therapy. Short-period bioimpedance and electrocardiographic data should be deeply evaluated to determine possible advantages in the therapeutic and prognostic approach in severe CHF.
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Affiliation(s)
- Gianfranco Piccirillo
- Department of Internal and Clinical Medicine, Anesthesiology and Cardiovascular Sciences, Policlinico Umberto I, “Sapienza” University of Rome, Viale del Policlinico n. 155, 00186 Rome, Italy
| | - Federica Moscucci
- Department of Internal and Clinical Medicine, Anesthesiology and Cardiovascular Sciences, Policlinico Umberto I, “Sapienza” University of Rome, Viale del Policlinico n. 155, 00186 Rome, Italy
- Correspondence: ; Tel.: +39-06-4997-0118
| | - Andrea Corrao
- Department of Internal and Clinical Medicine, Anesthesiology and Cardiovascular Sciences, Policlinico Umberto I, “Sapienza” University of Rome, Viale del Policlinico n. 155, 00186 Rome, Italy
| | - Myriam Carnovale
- Department of Internal and Clinical Medicine, Anesthesiology and Cardiovascular Sciences, Policlinico Umberto I, “Sapienza” University of Rome, Viale del Policlinico n. 155, 00186 Rome, Italy
| | - Ilaria Di Diego
- Department of Internal and Clinical Medicine, Anesthesiology and Cardiovascular Sciences, Policlinico Umberto I, “Sapienza” University of Rome, Viale del Policlinico n. 155, 00186 Rome, Italy
| | - Ilaria Lospinuso
- Department of Internal and Clinical Medicine, Anesthesiology and Cardiovascular Sciences, Policlinico Umberto I, “Sapienza” University of Rome, Viale del Policlinico n. 155, 00186 Rome, Italy
| | - Cristina Caltabiano
- Department of Internal and Clinical Medicine, Anesthesiology and Cardiovascular Sciences, Policlinico Umberto I, “Sapienza” University of Rome, Viale del Policlinico n. 155, 00186 Rome, Italy
| | - Martina Mezzadri
- Department of Internal and Clinical Medicine, Anesthesiology and Cardiovascular Sciences, Policlinico Umberto I, “Sapienza” University of Rome, Viale del Policlinico n. 155, 00186 Rome, Italy
| | - Pietro Rossi
- Arrhytmology Unit, Cardiology Division, S. Giovanni Calibita, Isola Tiberina, 00186 Rome, Italy
| | - Damiano Magrì
- Department of Clinical and Molecular Medicine, S. Andrea Hospital, “Sapienza” University of Rome, 00186 Rome, Italy
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Patel SI, Zareba W, LaFleur B, Couderc JP, Xia X, Woosley R, Patel IY, Combs D, Mashaqi S, Quan SF, Parthasarathy S. Markers of ventricular repolarization and overall mortality in sleep disordered breathing. Sleep Med 2022; 95:9-15. [PMID: 35533628 PMCID: PMC10563794 DOI: 10.1016/j.sleep.2022.04.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Revised: 04/04/2022] [Accepted: 04/18/2022] [Indexed: 11/20/2022]
Abstract
INTRODUCTION Variability and prolongation of ventricular repolarization - measured by changes in QT interval and QT variability are independently associated with ventricular arrhythmias, sudden death, and mortality but such studies did not examine the role of sleep-disordered breathing. We aimed to determine whether sleep-disordered breathing moderated the association between measures of ventricular repolarization and overall mortality. METHODS Eight hundred participants were randomly selected from each of the following four groups in the Sleep Heart Health Study: mild, moderate, severe or no sleep disordered breathing (n = 200 each). Overnight electrocardiograms were analyzed for QTc duration and QT variability (standard deviation of QT intervals, normalized QT interval variance and the short-term interval beat-to-beat QT variability). Cox proportional hazards penalized regression modeling was used to identify predictors of mortality. RESULTS Eight hundred of 5600 participants were randomly selected. The participants (68 ± 10 years; 56.8% male) were followed for an average of 8.2 years during which time 222 (28.4%) died. QTc, SDQT, and QTVN were associated with the presence of SDB (p = 0.002, p = 0.014, and p = 0.024, respectively). After adjusting for covariates, the presence of sleep-disordered breathing did not moderate the association between QTc length, QT variability and mortality (p > 0.05). CONCLUSION Sleep-disordered breathing was associated with some measures of ventricular repolarization. However, sleep-disordered breathing was not an effect modifier for the relationship between QTc and QT variability and mortality.
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Affiliation(s)
- Salma I Patel
- UAHS Center for Sleep and Circadian Sciences, University of Arizona, USA; Division of Pulmonary, Allergy, Critical Care Medicine and Sleep Medicine, University of Arizona College of Medicine, Tucson, USA.
| | - Wojciech Zareba
- Clinical Cardiovascular Research Center, University of Rochester Medical Center, USA
| | - Bonnie LaFleur
- UAHS Center for Biomedical Informatics and Biostatistics, University of Arizona, USA; BIO5, University of Arizona, USA; R. Ken Coit College of Pharmacy University of Arizona, USA
| | - Jean-Phillipe Couderc
- Clinical Cardiovascular Research Center, University of Rochester Medical Center, USA
| | - Xiaojuan Xia
- Clinical Cardiovascular Research Center, University of Rochester Medical Center, USA
| | - Raymond Woosley
- Division of Clinical Data Analytics and Decision Support, University of Arizona College of Medicine, Phoenix, USA
| | - Imran Y Patel
- UAHS Center for Sleep and Circadian Sciences, University of Arizona, USA; Division of Pulmonary, Allergy, Critical Care Medicine and Sleep Medicine, University of Arizona College of Medicine, Tucson, USA
| | - Daniel Combs
- UAHS Center for Sleep and Circadian Sciences, University of Arizona, USA; Department of Pediatrics, University of Arizona College of Medicine, Tucson, USA
| | - Saif Mashaqi
- UAHS Center for Sleep and Circadian Sciences, University of Arizona, USA; Division of Pulmonary, Allergy, Critical Care Medicine and Sleep Medicine, University of Arizona College of Medicine, Tucson, USA
| | - Stuart F Quan
- UAHS Center for Sleep and Circadian Sciences, University of Arizona, USA; Division of Pulmonary, Allergy, Critical Care Medicine and Sleep Medicine, University of Arizona College of Medicine, Tucson, USA; Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Harvard Medical School, USA
| | - Sairam Parthasarathy
- UAHS Center for Sleep and Circadian Sciences, University of Arizona, USA; Division of Pulmonary, Allergy, Critical Care Medicine and Sleep Medicine, University of Arizona College of Medicine, Tucson, USA
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Zhong Z, Li Q, Zou X, Ouyang Q, Zeng Q, Hu Y, Wang M, Luo Y, Yao D. Influence of Sleep Bruxism on QTc Interval and QT Variability in Patients with OSA: a pilot study. J Oral Rehabil 2022; 49:495-504. [PMID: 35158405 DOI: 10.1111/joor.13314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 01/29/2022] [Accepted: 02/08/2022] [Indexed: 11/28/2022]
Abstract
BACKGROUND Obstructive sleep apnea (OSA) is associated with increases in QT interval corrected for heart rate (QTc interval) and QT variability index (QTVI) and sleep bruxism (SB) is prevalent in OSA patients. OBJECTIVES To examine whether QTc interval and QT variability were changed during episodes of RMMAs/SB in SB patients with and without OSA. METHODS The RR and QTc intervals, and QTVI during RMMAs with or without accompanied limb movements (RMMAs/LMs) in 10 normal controls and 10 SB patients without OSA and during apneic and recovery periods of OSA in 10 SB patients with OSA were analyzed. RESULTS In the SB patients without OSA and controls, QTc intervals and QTVI were significantly increased during RMMAs/LMs compared with those during the 10 s periods (from 10th to 20th s) before the onset and after the offset of RMMAs/LMs, and significantly increased during RMMAs/LMs with awakenings compared with those with microarousals and no arousals. Moreover, QTc interval and QTVI were positively correlated with the duration of RMMAs/LMs. Moreover, in the SB patients with OSA, QTc interval and QTVI during the recovery period of OSA events were significantly longer and higher than those during the apneic period regardless of accompanied RMMAs/LMs, and QTc interval and QTVI during the apneic and recovery periods accompanied with RMMAs/LMs were significantly longer and higher than those without accompanied RMMAs/LMs. CONCLUSION OSA and RMMAs/LMs events were associated with longer QTc intervals and higher QTVI, and RMMAs/LMs might contribute to these changes associated with OSA events accompanied with RMMAs/LMs.
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Affiliation(s)
- Zhijun Zhong
- Neurological Institute of Jiangxi Province and Department of Neurology, Jiangxi Provincial People's Hospital, Nanchang Medical College and Nanchang University, Jiangxi, PR China
| | - Qi Li
- Department of Neurology, the Third Affiliated Hospital, Nanchang University, Jiangxi, PR China
| | - Xueliang Zou
- Jiangxi Mental Hospital, Nanchang University, Jiangxi, PR China
| | - Qian Ouyang
- Neurological Institute of Jiangxi Province and Department of Neurology, Jiangxi Provincial People's Hospital, Nanchang Medical College and Nanchang University, Jiangxi, PR China
| | - Qinghong Zeng
- Neurological Institute of Jiangxi Province and Department of Neurology, Jiangxi Provincial People's Hospital, Nanchang Medical College and Nanchang University, Jiangxi, PR China.,School of Pharmaceutical Sciences, Nanchang University, Jiangxi, PR China
| | - Yinyin Hu
- Neurological Institute of Jiangxi Province and Department of Neurology, Jiangxi Provincial People's Hospital, Nanchang Medical College and Nanchang University, Jiangxi, PR China.,School of Pharmaceutical Sciences, Nanchang University, Jiangxi, PR China
| | - Mengmeng Wang
- Neurological Institute of Jiangxi Province and Department of Neurology, Jiangxi Provincial People's Hospital, Nanchang Medical College and Nanchang University, Jiangxi, PR China.,School of Pharmaceutical Sciences, Nanchang University, Jiangxi, PR China
| | - Yaxing Luo
- Neurological Institute of Jiangxi Province and Department of Neurology, Jiangxi Provincial People's Hospital, Nanchang Medical College and Nanchang University, Jiangxi, PR China.,School of Pharmaceutical Sciences, Nanchang University, Jiangxi, PR China
| | - Dongyuan Yao
- Neurological Institute of Jiangxi Province and Department of Neurology, Jiangxi Provincial People's Hospital, Nanchang Medical College and Nanchang University, Jiangxi, PR China
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Song ZL, Liu Y, Liu X, Qin M. Absence of Rgs5 Influences the Spatial and Temporal Fluctuation of Cardiac Repolarization in Mice. Front Physiol 2021; 12:622084. [PMID: 33815137 PMCID: PMC8012757 DOI: 10.3389/fphys.2021.622084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Accepted: 02/22/2021] [Indexed: 11/25/2022] Open
Abstract
Aims This study investigated the contribution of the regulator of G-protein signaling 5 (Rgs5) knockout to the alteration of the action potential duration (APD) restitution and repolarizing dispersion in ventricle. Methods and Results The effects of Rgs5–/– were investigated by QT variance (QTv) and heart rate variability analysis of Rgs5–/– mice. Monophasic action potential analysis was investigated in isolated Rgs5–/– heart. Rgs5–/– did not promote ventricular remodeling. The 24-h QTv and QT variability index (QTVI) of the Rgs5–/– mice were higher than those of wild-type (WT) mice (P < 0.01). In WT mice, a positive correlation was found between QTv and the standard deviation of all NN intervals (r = 0.62; P < 0.01), but not in Rgs5–/– mice (R = 0.01; P > 0.05). The absence of Rgs5 resulted in a significant prolongation of effective refractory period and APD in isolated ventricle. In addition, compared with WT mice, the knockout of Rgs5 significantly deepened the slope of the APD recovery curve at all 10 sites of the heart (P < 0.01) and increased the spatial dispersions of Smax (COV-Smax) (WT: 0.28 ± 0.03, Rgs5–/–: 0.53 ± 0.08, P < 0.01). Compared with WT heart, Rgs5–/– increased the induced S1–S2 interval at all sites of heart and widened the window of vulnerability of ventricular tachyarrhythmia (P < 0.05). Conclusion Our findings indicate that Rgs5–/– is an important regulator of ventricular tachyarrhythmia in mice by prolonging ventricular repolarization and increasing spatial dispersion in ventricle.
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Affiliation(s)
- Zi-Liang Song
- Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China
| | - Yang Liu
- Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China
| | - Xu Liu
- Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China
| | - Mu Qin
- Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China
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Andršová I, Hnatkova K, Šišáková M, Toman O, Smetana P, Huster KM, Barthel P, Novotný T, Schmidt G, Malik M. Heart Rate Influence on the QT Variability Risk Factors. Diagnostics (Basel) 2020; 10:diagnostics10121096. [PMID: 33339231 PMCID: PMC7767205 DOI: 10.3390/diagnostics10121096] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Revised: 12/05/2020] [Accepted: 12/14/2020] [Indexed: 12/14/2022] Open
Abstract
QT interval variability, mostly expressed by QT variability index (QTVi), has repeatedly been used in risk diagnostics. Physiologic correlates of QT variability expressions have been little researched especially when measured in short 10-second electrocardiograms (ECGs). This study investigated different QT variability indices, including QTVi and the standard deviation of QT interval durations (SDQT) in 657,287 10-second ECGs recorded in 523 healthy subjects (259 females). The indices were related to the underlying heart rate and to the 10-second standard deviation of RR intervals (SDRR). The analyses showed that both QTVi and SDQT (as well as other QT variability indices) were highly statistically significantly (p < 0.00001) influenced by heart rate and that QTVi showed poor intra-subject reproducibility (coefficient of variance approaching 200%). Furthermore, sequential analysis of regression variance showed that SDQT was more strongly related to the underlying heart rate than to SDRR, and that QTVi was influenced by the underlying heart rate and SDRR more strongly than by SDQT (p < 0.00001 for these comparisons of regression dependency). The study concludes that instead of QTVi, simpler expressions of QT interval variability, such as SDQT, appear preferable for future applications especially if multivariable combination with the underlying heart rate is used.
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Affiliation(s)
- Irena Andršová
- Department of Internal Medicine and Cardiology, University Hospital Brno, Faculty of Medicine, Masaryk University, Jihlavská 20, 625 00 Brno, Czech Republic; (I.A.); (M.Š.); (O.T.); (T.N.)
| | - Katerina Hnatkova
- National Heart and Lung Institute, Imperial College, 72 Du Cane Road, Shepherd’s Bush, London W12 0NN, UK;
| | - Martina Šišáková
- Department of Internal Medicine and Cardiology, University Hospital Brno, Faculty of Medicine, Masaryk University, Jihlavská 20, 625 00 Brno, Czech Republic; (I.A.); (M.Š.); (O.T.); (T.N.)
| | - Ondřej Toman
- Department of Internal Medicine and Cardiology, University Hospital Brno, Faculty of Medicine, Masaryk University, Jihlavská 20, 625 00 Brno, Czech Republic; (I.A.); (M.Š.); (O.T.); (T.N.)
| | - Peter Smetana
- Wilhelminenspital der Stadt Wien, Montleartstraße 37, 1160 Vienna, Austria;
| | - Katharina M. Huster
- Klinikum rechts der Isar, Technische Universität München, Ismaninger Straße 22, D-81675 Munich, Germany; (K.M.H.); (P.B.); (G.S.)
| | - Petra Barthel
- Klinikum rechts der Isar, Technische Universität München, Ismaninger Straße 22, D-81675 Munich, Germany; (K.M.H.); (P.B.); (G.S.)
| | - Tomáš Novotný
- Department of Internal Medicine and Cardiology, University Hospital Brno, Faculty of Medicine, Masaryk University, Jihlavská 20, 625 00 Brno, Czech Republic; (I.A.); (M.Š.); (O.T.); (T.N.)
| | - Georg Schmidt
- Klinikum rechts der Isar, Technische Universität München, Ismaninger Straße 22, D-81675 Munich, Germany; (K.M.H.); (P.B.); (G.S.)
| | - Marek Malik
- National Heart and Lung Institute, Imperial College, 72 Du Cane Road, Shepherd’s Bush, London W12 0NN, UK;
- Department of Internal Medicine and Cardiology, Faculty of Medicine, Masaryk University, Jihlavská 20, 625 00 Brno, Czech Republic
- Correspondence:
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9
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Piccirillo G, Moscucci F, Iorio CD, Fabietti M, Mastropietri F, Crapanzano D, Bertani G, Sabatino T, Zaccagnini G, Lospinuso I, Magrì D. Time- and frequency-domain analysis of repolarization phase during recovery from exercise in healthy subjects. Pacing Clin Electrophysiol 2020; 43:1096-1103. [PMID: 32789871 DOI: 10.1111/pace.14038] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 07/28/2020] [Accepted: 08/09/2020] [Indexed: 01/18/2023]
Abstract
BACKGROUND/AIM Recently, data from temporal dispersion of myocardial repolarization analysis have gained a capital role in the sudden cardiac death risk stratification. Aim of this study was to evaluate the influence of heart rate, autonomic nervous system, and controlled breathing on different myocardial repolarization markers in healthy subjects. METHOD Myocardial repolarization dispersion markers from short-period (5 minutes) electrocardiogram (ECG) analysis (time and frequency domain) have been obtained in 21 healthy volunteers during the following conditions: free breathing (rest); controlled breathing (resp); the first 5 minutes of postexercise recovery phases (exercisePeak ), maximum sympathetic activation; and during the second 5 minutes of postexercise recovery phases (exerciseRecovery ), intermediate sympathetic activation. Finally, we analyzed the whole repolarization (QTe), the QT peak (QTp), and T peak - T end intervals (Te). RESULTS During the exercisePeak , major part of repolarization variables changed in comparison to the rest and resp conditions. Particularly, QTe, QTp, and Te standard deviations (QTeSD , QTpSD , and TeSD ); variability indexes (QTeVI and QTpVI), normalized variances (QTeVN, QTpVN, and TeVN); and the ratio between short-term QTe, QTp, and Te variability RR (STVQTe/RR , STVQTp/RR, and STVTe/RR ) increased. During exerciseRecovery , QTpSD (P < .05), QTpVI (P < .05), QTeVN (P < .05), QTpVN (P < .001), TeVN (P < .05), STVQTe/RR (P < .05), STVQTp/RR (P < .001), and STVTe/RR (P < .001) were significantly higher in comparison to the rest. The slope between QTe (0.24 ± 0.06) or QTp (0.17 ± 0.06) and RR were significantly higher than Te (0.07 ± 0.06, P < .001). CONCLUSION Heart rate and sympathetic activity, obtained during exercise, seem able to influence the time domain markers of myocardial repolarization dispersion in healthy subjects, whereas they do not alter any spectral components.
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Affiliation(s)
- Gianfranco Piccirillo
- Dipartimento di Scienze Cliniche, Internistiche, Anestesiologiche e Cardiovascolari, Policlinico Umberto I, Sapienza University of Rome, Rome, Italy
| | - Federica Moscucci
- Dipartimento di Scienze Cliniche, Internistiche, Anestesiologiche e Cardiovascolari, Policlinico Umberto I, Sapienza University of Rome, Rome, Italy
| | - Claudia Di Iorio
- Dipartimento di Scienze Cliniche, Internistiche, Anestesiologiche e Cardiovascolari, Policlinico Umberto I, Sapienza University of Rome, Rome, Italy
| | - Marcella Fabietti
- Dipartimento di Scienze Cliniche, Internistiche, Anestesiologiche e Cardiovascolari, Policlinico Umberto I, Sapienza University of Rome, Rome, Italy
| | - Fabiola Mastropietri
- Dipartimento di Scienze Cliniche, Internistiche, Anestesiologiche e Cardiovascolari, Policlinico Umberto I, Sapienza University of Rome, Rome, Italy
| | - Davide Crapanzano
- Dipartimento di Scienze Cliniche, Internistiche, Anestesiologiche e Cardiovascolari, Policlinico Umberto I, Sapienza University of Rome, Rome, Italy
| | - Gaetano Bertani
- Dipartimento di Scienze Cliniche, Internistiche, Anestesiologiche e Cardiovascolari, Policlinico Umberto I, Sapienza University of Rome, Rome, Italy
| | - Teresa Sabatino
- Dipartimento di Scienze Cliniche, Internistiche, Anestesiologiche e Cardiovascolari, Policlinico Umberto I, Sapienza University of Rome, Rome, Italy
| | - Giulia Zaccagnini
- Dipartimento di Scienze Cliniche, Internistiche, Anestesiologiche e Cardiovascolari, Policlinico Umberto I, Sapienza University of Rome, Rome, Italy
| | - Ilaria Lospinuso
- Dipartimento di Scienze Cliniche, Internistiche, Anestesiologiche e Cardiovascolari, Policlinico Umberto I, Sapienza University of Rome, Rome, Italy
| | - Damiano Magrì
- Dipartimento di Medicina Clinica e Molecolare, S. Andrea Hospital, Sapienza University of Rome, Rome, Italy
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10
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Piccirillo G, Moscucci F, Mariani MV, Di Iorio C, Fabietti M, Mastropietri F, Crapanzano D, Bertani G, Sabatino T, Zaccagnini G, Lospinuso I, Rossi P, Magrì D. Hospital mortality in decompensated heart failure. A pilot study. J Electrocardiol 2020; 61:147-152. [PMID: 32629315 DOI: 10.1016/j.jelectrocard.2020.05.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Revised: 04/29/2020] [Accepted: 05/09/2020] [Indexed: 12/27/2022]
Abstract
BACKGROUND/AIM Heart failure is a leading cause of morbidity and mortality worldwide and it is a major cause of emergency department access for cardiovascular disease patients. Aim of this study was to identify the electrocardiographic (ECG) markers, based on short-term temporal repolarization dispersion, capable to individuate decompensated chronic heart failure (CHF) patients at high mortality risk. METHODS We obtained the following variables from an ECG recording, monitored via mobile phone, during 5-minute recordings in decompensated CHF patients: RR, QT end (QTe), QT peak (QTp) and T peak to T end (Te) and we calculated mean, standard deviation (SD) and normalized index (N). RESULTS In-hospital mortality occurred for 25 subjects on 101 studied (25%). Deceased patients showed higher QTeSD (p < 0.01), Te mean (p < 0.01), TeSD (p < 0.05), QTeVN (p < 0.05) than the surviving group. Logistic multivariable analysis evidenced that Te mean was a significant predictor of in-hospital mortality (odd ratio: 0.09, 95% confidence limit: 0.02-0.35, p: 0.001). At multiple regression analysis, TeSD was significantly and positively related only to the NT-pro BNP levels (r: 0.540; p < 0.001). The Te mean (AUC: 0.677 p < 0.01) and TeSD (AUC: 0.647, p: 0.05) showed significant sensitivity/specificity for the event. CONCLUSIONS The Te mean and TeSD seem to be a promising noninvasive clinical marker able to identify patients with decompensated CHF at high risk of in-hospital mortality.
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Affiliation(s)
- Gianfranco Piccirillo
- Dipartimento di Scienze Cliniche, Internistiche, Anestesiologiche e Cardiovascolari, Policlinico Umberto I, "La Sapienza" University of Rome, Viale del Policlinico N. 155, 00185 Roma, Italy
| | - Federica Moscucci
- Dipartimento di Scienze Cliniche, Internistiche, Anestesiologiche e Cardiovascolari, Policlinico Umberto I, "La Sapienza" University of Rome, Viale del Policlinico N. 155, 00185 Roma, Italy.
| | - Marco Valerio Mariani
- Dipartimento di Scienze Cliniche, Internistiche, Anestesiologiche e Cardiovascolari, Policlinico Umberto I, "La Sapienza" University of Rome, Viale del Policlinico N. 155, 00185 Roma, Italy
| | - Claudia Di Iorio
- Dipartimento di Scienze Cliniche, Internistiche, Anestesiologiche e Cardiovascolari, Policlinico Umberto I, "La Sapienza" University of Rome, Viale del Policlinico N. 155, 00185 Roma, Italy
| | - Marcella Fabietti
- Dipartimento di Scienze Cliniche, Internistiche, Anestesiologiche e Cardiovascolari, Policlinico Umberto I, "La Sapienza" University of Rome, Viale del Policlinico N. 155, 00185 Roma, Italy
| | - Fabiola Mastropietri
- Dipartimento di Scienze Cliniche, Internistiche, Anestesiologiche e Cardiovascolari, Policlinico Umberto I, "La Sapienza" University of Rome, Viale del Policlinico N. 155, 00185 Roma, Italy
| | - Davide Crapanzano
- Dipartimento di Scienze Cliniche, Internistiche, Anestesiologiche e Cardiovascolari, Policlinico Umberto I, "La Sapienza" University of Rome, Viale del Policlinico N. 155, 00185 Roma, Italy
| | - Gaetano Bertani
- Dipartimento di Scienze Cliniche, Internistiche, Anestesiologiche e Cardiovascolari, Policlinico Umberto I, "La Sapienza" University of Rome, Viale del Policlinico N. 155, 00185 Roma, Italy
| | - Teresa Sabatino
- Dipartimento di Scienze Cliniche, Internistiche, Anestesiologiche e Cardiovascolari, Policlinico Umberto I, "La Sapienza" University of Rome, Viale del Policlinico N. 155, 00185 Roma, Italy
| | - Giulia Zaccagnini
- Dipartimento di Scienze Cliniche, Internistiche, Anestesiologiche e Cardiovascolari, Policlinico Umberto I, "La Sapienza" University of Rome, Viale del Policlinico N. 155, 00185 Roma, Italy
| | - Ilaria Lospinuso
- Dipartimento di Scienze Cliniche, Internistiche, Anestesiologiche e Cardiovascolari, Policlinico Umberto I, "La Sapienza" University of Rome, Viale del Policlinico N. 155, 00185 Roma, Italy
| | - Pietro Rossi
- Division of Cardiology, S. Giovanni Calibita Fatebenefratelli Hospital, Isola Tiberina, Piazza Ponte dei Quattro Capi, 39 186 Roma, Italy
| | - Damiano Magrì
- Dipartimento di Medicina Clinica e Molecolare, S. Andrea Hospital, "Sapienza" University of Rome, Via di Grottarossa 1035/1039, k00189 Rome, Italy
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11
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Orini M, Al-Amodi F, Koelsch S, Bailón R. The Effect of Emotional Valence on Ventricular Repolarization Dynamics Is Mediated by Heart Rate Variability: A Study of QT Variability and Music-Induced Emotions. Front Physiol 2019; 10:1465. [PMID: 31849711 PMCID: PMC6895139 DOI: 10.3389/fphys.2019.01465] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Accepted: 11/14/2019] [Indexed: 12/20/2022] Open
Abstract
Background Emotions can affect cardiac activity, but their impact on ventricular repolarization variability, an important parameter providing information about cardiac risk and autonomic nervous system activity, is unknown. The beat-to-beat variability of the QT interval (QTV) from the body surface ECG is a non-invasive marker of repolarization variability, which can be decomposed into QTV related to RR variability (QTVrRRV) and QTV unrelated to RRV (QTVuRRV), with the latter thought to be a marker of intrinsic repolarization variability. Aim To determine the effect of emotional valence (pleasant and unpleasant) on repolarization variability in healthy volunteers by means of QTV analysis. Methods 75 individuals (24.5 ± 3.2 years, 36 females) without a history of cardiovascular disease listened to music-excerpts that were either felt as pleasant (n = 6) or unpleasant (n = 6). Excerpts lasted about 90 s and were presented in a random order along with silent intervals (n = 6). QTV and RRV were derived from the ECG and the time-frequency spectrum of RRV, QTV, QTVuRRV and QTVrRRV as well as time-frequency coherence between QTV and RRV were estimated. Analysis was performed in low-frequency (LF), high frequency (HF) and total spectral bands. Results The heart rate-corrected QTV showed a small but significant increase from silence (median 347/interquartile range 31 ms) to listening to music felt as unpleasant (351/30 ms) and pleasant (355/32 ms). The dynamic response of QTV to emotional valence showed a transient phase lasting about 20 s after the onset of each musical excerpt. QTV and RRV were highly correlated in both HF and LF (mean coherence ranging 0.76–0.85). QTV and QTVrRRV decreased during listening to music felt as pleasant and unpleasant with respect to silence and further decreased during listening to music felt as pleasant. QTVuRRV was small and not affected by emotional valence. Conclusion Emotional valence, as evoked by music, has a small but significant effect on QTV and QTVrRRV, but not on QTVuRRV. This suggests that the interaction between emotional valence and ventricular repolarization variability is mediated by cycle length dynamics and not due to intrinsic repolarization variability.
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Affiliation(s)
- Michele Orini
- Institute of Cardiovascular Sciences, University College London, London, United Kingdom.,The William Harvey Research Institute, Queen Mary University of London, London, United Kingdom
| | - Faez Al-Amodi
- Institute of Cardiovascular Sciences, University College London, London, United Kingdom
| | - Stefan Koelsch
- Department of Biological and Medical Psychology, University of Bergen, Bergen, Norway
| | - Raquel Bailón
- Aragon Institute for Engineering Research, University of Zaragoza, Zaragoza, Spain.,Center for Biomedical Research in the Network in Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Madrid, Spain
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12
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van den Berg ME, Kors JA, van Herpen G, Bots ML, Hillege H, Swenne CA, Stricker BH, Rijnbeek PR. Normal Values of QT Variability in 10-s Electrocardiograms for all Ages. Front Physiol 2019; 10:1272. [PMID: 31636572 PMCID: PMC6788348 DOI: 10.3389/fphys.2019.01272] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Accepted: 09/19/2019] [Indexed: 12/02/2022] Open
Abstract
Aims: QT variability is a promising electrocardiographic marker. It has been studied as a screening tool for coronary artery disease and left ventricular hypertrophy, and increased QT variability is a known risk factor for sudden cardiac death. Considering that comprehensive normal values for QT variability were lacking, we set out to establish these in standard 10-s electrocardiograms (ECGs) covering both sexes and all ages. Methods: Ten-second, 12-lead ECGs were provided by five Dutch population studies (Pediatric Normal ECG Study, Leiden University Einthoven Science Project, Prevention of Renal and Vascular End-stage Disease Study, Utrecht Health Project, Rotterdam Study). ECGs were recorded digitally and processed by well-validated analysis software. We selected cardiologically healthy participants, 46% being women. Ages ranged from 11 days to 91 years. After quality control, 13,828 ECGs were available. We assessed three markers: standard deviation of QT intervals (SDqt), short-term QT variability (STVqt), and QT variability index (QTVI). Results: For SDqt and STVqt, the median and the lower limit of normal remained stable with age. The upper limit of normal declined until around age 45, and increased strongly in the elderly, notably so in women. This implies that a subset of the population, small enough not to have appreciable effect on the median, shows a high degree of QT variability with a possible risk of arrhythmias or worse, especially in women. Otherwise, sex differences were negligible in all three measurements. For QTVI, median, and normal limits decreased until age 20, and steadily went up afterwards except for the lower limit of normal, which flattens off after age 65. Conclusion: We report the first set of normal values for QT variability based on 10-s ECGs, for all ages and both sexes.
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Affiliation(s)
- Marten E van den Berg
- Department of Medical Informatics, Erasmus MC - University Medical Center Rotterdam, Rotterdam, Netherlands
| | - Jan A Kors
- Department of Medical Informatics, Erasmus MC - University Medical Center Rotterdam, Rotterdam, Netherlands
| | - Gerard van Herpen
- Department of Medical Informatics, Erasmus MC - University Medical Center Rotterdam, Rotterdam, Netherlands
| | - Michiel L Bots
- Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands
| | - Hans Hillege
- Department of Cardiology, University Medical Center Groningen, Groningen, Netherlands
| | - Cees A Swenne
- Department of Cardiology, Leiden University Medical Center, Leiden, Netherlands
| | - Bruno H Stricker
- Department of Epidemiology, Erasmus MC - University Medical Center Rotterdam, Rotterdam, Netherlands.,Department of Internal Medicine, Erasmus MC - University Medical Center Rotterdam, Rotterdam, Netherlands.,Inspectorate of Health Care, Utrecht, Netherlands
| | - Peter R Rijnbeek
- Department of Medical Informatics, Erasmus MC - University Medical Center Rotterdam, Rotterdam, Netherlands
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13
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Piccirillo G, Moscucci F, Fabietti M, Parrotta I, Mastropietri F, Di Iorio C, Sabatino T, Crapanzano D, Vespignani G, Mariani MV, Salvi N, Magrì D. Arrhythmic Risk in Elderly Patients Candidates to Transcatheter Aortic Valve Replacement: Predictive Role of Repolarization Temporal Dispersion. Front Physiol 2019; 10:991. [PMID: 31447689 PMCID: PMC6691061 DOI: 10.3389/fphys.2019.00991] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Accepted: 07/18/2019] [Indexed: 12/30/2022] Open
Abstract
Background/Aim Degenerative aortic valve stenosis (AS) is associated to ventricular arrhythmias and sudden cardiac death, as well as mental stress in specific patients. In such a context, substrate, autonomic imbalance as well as repolarization dispersion abnormalities play an undoubted role. Aim of the study was to evaluate the increase of premature ventricular contractions (PVC) and complex ventricular arrhythmias during mental stress in elderly patients candidate to the transcatheter aortic valve replacement (TAVR). Methods In eighty-one elderly patients with AS we calculated several short-period RR- and QT-derived variables at rest, during controlled breathing and during mild mental stress, the latter being represented by a mini-mental state evaluation (MMSE). Results All the myocardial repolarization dispersion markers worsened during mental stress (p < 0.05). Furthermore, during MMSE, low frequency component of the RR variability increased significantly both as absolute power (LFRR) and normalized units (LFRRN U) (p < 0.05) as well as the low-high frequency ratio (LFRR/HFRR) (p < 0.05). Eventually, twenty-four (30%) and twelve (15%) patients increased significantly PVC and, respectively, complex ventricular arrhythmias during the MMSE administration. At multivariate logistic regression analysis, the standard deviation of QTend (QTesd), obtained at rest, was predictive of increased PVC (odd ratio: 1.54, 95% CI 1.14-2.08; p = 0.005) and complex ventricular arrhythmias (odd ratio: 2.31, 95% CI 1.40-3.83; p = 0.001) during MMSE. The QTesd showed the widest sensitive-specificity area under the curve for the increase of PVC (AUC: 0.699, 95% CI: 0.576-0.822, p < 0.05) and complex ventricular arrhythmias (AUC: 0.801, 95% CI: 0.648-0.954, p < 0.05). Conclusion In elderly with AS ventricular arrhythmias worsened during a simple cognitive assessment, this events being a possible further burden on the outcome of TAVR. QTesd might be useful to identify those patients with the highest risk of ventricular arrhythmias. Whether the TAVR could led to a QTesd reduction and, hence, to a reduction of the arrhythmic burden in this setting of patients is worthy to be investigated.
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Affiliation(s)
- Gianfranco Piccirillo
- Dipartimento di Scienze Cardiovascolari, Respiratorie, Geriatriche, Anestesiologiche e Nefrologiche, Policlinico Umberto I, "La Sapienza" University of Rome, Rome, Italy
| | - Federica Moscucci
- Dipartimento di Scienze Cardiovascolari, Respiratorie, Geriatriche, Anestesiologiche e Nefrologiche, Policlinico Umberto I, "La Sapienza" University of Rome, Rome, Italy
| | - Marcella Fabietti
- Dipartimento di Scienze Cardiovascolari, Respiratorie, Geriatriche, Anestesiologiche e Nefrologiche, Policlinico Umberto I, "La Sapienza" University of Rome, Rome, Italy
| | - Ilaria Parrotta
- Dipartimento di Scienze Cardiovascolari, Respiratorie, Geriatriche, Anestesiologiche e Nefrologiche, Policlinico Umberto I, "La Sapienza" University of Rome, Rome, Italy
| | - Fabiola Mastropietri
- Dipartimento di Scienze Cardiovascolari, Respiratorie, Geriatriche, Anestesiologiche e Nefrologiche, Policlinico Umberto I, "La Sapienza" University of Rome, Rome, Italy
| | - Claudia Di Iorio
- Dipartimento di Scienze Cardiovascolari, Respiratorie, Geriatriche, Anestesiologiche e Nefrologiche, Policlinico Umberto I, "La Sapienza" University of Rome, Rome, Italy
| | - Teresa Sabatino
- Dipartimento di Scienze Cardiovascolari, Respiratorie, Geriatriche, Anestesiologiche e Nefrologiche, Policlinico Umberto I, "La Sapienza" University of Rome, Rome, Italy
| | - Davide Crapanzano
- Dipartimento di Scienze Cardiovascolari, Respiratorie, Geriatriche, Anestesiologiche e Nefrologiche, Policlinico Umberto I, "La Sapienza" University of Rome, Rome, Italy
| | - Giulia Vespignani
- Dipartimento di Scienze Cardiovascolari, Respiratorie, Geriatriche, Anestesiologiche e Nefrologiche, Policlinico Umberto I, "La Sapienza" University of Rome, Rome, Italy
| | - Marco Valerio Mariani
- Dipartimento di Scienze Cardiovascolari, Respiratorie, Geriatriche, Anestesiologiche e Nefrologiche, Policlinico Umberto I, "La Sapienza" University of Rome, Rome, Italy
| | - Nicolò Salvi
- Dipartimento di Scienze Cardiovascolari, Respiratorie, Geriatriche, Anestesiologiche e Nefrologiche, Policlinico Umberto I, "La Sapienza" University of Rome, Rome, Italy
| | - Damiano Magrì
- Dipartimento di Medicina Clinica e Molecolare, S. Andrea Hospital, "Sapienza" University of Rome, Rome, Italy
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14
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Cankar K, Melik Z, Kobal J, Starc V. Evidence of cardiac electrical remodeling in patients with Huntington disease. Brain Behav 2018; 8:e01077. [PMID: 30028085 PMCID: PMC6085913 DOI: 10.1002/brb3.1077] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Revised: 06/29/2018] [Accepted: 07/01/2018] [Indexed: 12/28/2022] Open
Abstract
OBJECTIVE Although Huntington's disease (HD) is a disease of the central nervous system, HD mortality surveys indicate heart disease as a major cause of death. Cardiac dysfunction in HD might be a primary consequence of peripherally expressed mutant huntingtin or secondary to either a general decline in health or the onset of neurological dysfunction. The aim of the study was to clarify the heart muscle involvement. MATERIALS AND METHODS We measured conventional and advanced resting ECG indices. Thirty-one subjects with a confirmed huntingtin gene mutation and 31 age- and gender-matched controls were included. The HD subjects were divided into four groups based on their Unified Huntington Disease Rating Scale (UHDRS) motor score. RESULTS We detected changes in advanced ECG variables connected with electrical ventricular remodeling (t test, p < 0.01). The increase in the unexplained part of both QT variability and the standard deviation of normal-to-normal QT intervals, presumably reflecting beat-to-beat changes in repolarization, was most pronounced. Further, both variables correlated with the product of the cytosine-adenine-guanine (CAG) triplets' repeat length and the subjects' age (CAP), the former R = 0.423 (p = 0.018) and the latter R = 0.499 (p = 0.004). There was no correlation between the CAP score and any of variables representing autonomic nervous system activity. CONCLUSIONS Both autonomic nervous system dysfunction and cardiac electrical remodeling are present in patients with HD. The changes in advanced ECG variables observed in the study evolve with HD progression. The increased values of QT unexplained variability may be a marker of temporal inhomogeneity in ventricular repolarization associated with malignant ventricular arrhythmias.
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Affiliation(s)
- Ksenija Cankar
- Faculty of medicineInstitute of PhysiologyUniversity of LjubljanaLjubljanaSlovenia
| | - Ziva Melik
- Faculty of medicineInstitute of PhysiologyUniversity of LjubljanaLjubljanaSlovenia
| | - Jan Kobal
- Division of NeurologyUniversity Medical Centre LjubljanaLjubljanaSlovenia
| | - Vito Starc
- Faculty of medicineInstitute of PhysiologyUniversity of LjubljanaLjubljanaSlovenia
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15
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Wu HT, Soliman EZ. A new approach for analysis of heart rate variability and QT variability in long-term ECG recording. Biomed Eng Online 2018; 17:54. [PMID: 29720178 PMCID: PMC5932763 DOI: 10.1186/s12938-018-0490-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Accepted: 04/23/2018] [Indexed: 12/29/2022] Open
Abstract
Background and purpose With the emergence of long-term electrocardiogram (ECG) recordings that extend several days beyond the typical 24–48 h, the development of new tools to measure heart rate variability (HRV) and QT variability is needed to utilize the full potential of such extra-long-term ECG recordings. Methods In this report, we propose a new nonlinear time–frequency analysis approach, the concentration of frequency and time (ConceFT), to study the HRV QT variability from extra-long-term ECG recordings. This approach is a generalization of Short Time Fourier Transform and Continuous Wavelet Transform approaches. Results As proof of concept, we used 14-day ECG recordings to show that the ConceFT provides a sharpened and stabilized spectrogram by taking the phase information of the time series and the multitaper technique into account. Conclusion The ConceFT has the potential to provide a sharpened and stabilized spectrogram for the heart rate variability and QT variability in 14-day ECG recordings. Electronic supplementary material The online version of this article (10.1186/s12938-018-0490-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Hau-Tieng Wu
- Department of Mathematics and Department of Statistical Science, Duke University, 207 Physics Building, 120 Science Dr, Durham, NC, 27705, USA. .,Mathematics Division, National Center for Theoretical Sciences, Taipei, Taiwan.
| | - Elsayed Z Soliman
- Epidemiological Cardiology Research Center (EPICARE), Department of Epidemiology, Wake Forest School of Medicine, Winston-Salem, NC, USA.,Department of Internal Medicine, Section on Cardiology, Wake Forest School of Medicine, Winston-Salem, NC, USA
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16
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Piccirillo G, Ottaviani C, Fiorucci C, Petrocchi N, Moscucci F, Di Iorio C, Mastropietri F, Parrotta I, Pascucci M, Magrì D. Transcranial direct current stimulation improves the QT variability index and autonomic cardiac control in healthy subjects older than 60 years. Clin Interv Aging 2016; 11:1687-1695. [PMID: 27895475 PMCID: PMC5117948 DOI: 10.2147/cia.s116194] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Background Noninvasive brain stimulation technique is an interesting tool to investigate the causal relation between cortical functioning and autonomic nervous system (ANS) responses. Objective The objective of this report is to evaluate whether anodal transcranial direct current stimulation (tDCS) over the temporal cortex influences short-period temporal ventricular repolarization dispersion and cardiovascular ANS control in elderly subjects. Subjects and methods In 50 healthy subjects (29 subjects younger than 60 years and 21 subjects older than 60 years) matched for gender, short-period RR and systolic blood pressure spectral variability, QT variability index (QTVI), and noninvasive hemodynamic data were obtained during anodal tDCS or sham stimulation. Results In the older group, the QTVI, low-frequency (LF) power expressed in normalized units, the ratio between LF and high-frequency (HF) power, and systemic peripheral resistances decreased, whereas HF power expressed in normalized units and α HF power increased during the active compared to the sham condition (P<0.05). Conclusion In healthy subjects older than 60 years, tDCS elicits cardiovascular and autonomic changes. Particularly, it improves temporal ventricular repolarization dispersion, reduces sinus sympathetic activity and systemic peripheral resistance, and increases vagal sinus activity and baroreflex sensitivity.
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Affiliation(s)
- Gianfranco Piccirillo
- Department of Cardiovascular, Respiratory, Nephrological, Anestesiological and Geriatric Sciences, "Sapienza" University
| | | | - Claudia Fiorucci
- Department of Cardiovascular, Respiratory, Nephrological, Anestesiological and Geriatric Sciences, "Sapienza" University
| | | | - Federica Moscucci
- Department of Cardiovascular, Respiratory, Nephrological, Anestesiological and Geriatric Sciences, "Sapienza" University
| | - Claudia Di Iorio
- Department of Cardiovascular, Respiratory, Nephrological, Anestesiological and Geriatric Sciences, "Sapienza" University
| | - Fabiola Mastropietri
- Department of Cardiovascular, Respiratory, Nephrological, Anestesiological and Geriatric Sciences, "Sapienza" University
| | - Ilaria Parrotta
- Department of Cardiovascular, Respiratory, Nephrological, Anestesiological and Geriatric Sciences, "Sapienza" University
| | - Matteo Pascucci
- Department of Cardiovascular, Respiratory, Nephrological, Anestesiological and Geriatric Sciences, "Sapienza" University
| | - Damiano Magrì
- Department of Clinical and Molecular Medicine, University of Rome "Sapienza", Rome, Italy
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17
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DeMazumder D, Limpitikul WB, Dorante M, Dey S, Mukhopadhyay B, Zhang Y, Moorman JR, Cheng A, Berger RD, Guallar E, Jones SR, Tomaselli GF. Entropy of cardiac repolarization predicts ventricular arrhythmias and mortality in patients receiving an implantable cardioverter-defibrillator for primary prevention of sudden death. Europace 2016; 18:1818-1828. [PMID: 27044982 DOI: 10.1093/europace/euv399] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Accepted: 11/03/2015] [Indexed: 11/12/2022] Open
Abstract
AIMS The need for a readily available, inexpensive, non-invasive method for improved risk stratification of heart failure (HF) patients is paramount. Prior studies have proposed that distinct fluctuation patterns underlying the variability of physiological signals have unique prognostic value. We tested this hypothesis in an extensively phenotyped cohort of HF patients using EntropyXQT, a novel non-linear measure of cardiac repolarization dynamics. METHODS AND RESULTS In a prospective, multicentre, observational study of 852 patients in sinus rhythm undergoing clinically indicated primary prevention implantable cardioverter-defibrillator (ICD) implantation (2003-10), exposures included demographics, history, physical examination, medications, laboratory results, serum biomarkers, ejection fraction, conventional electrocardiographic (ECG) analyses of heart rate and QT variability, and EntropyXQT. The primary outcome was first 'appropriate' ICD shock for ventricular arrhythmias. The secondary outcome was composite events (appropriate ICD shock and all-cause mortality). After exclusions, the cohort (n = 816) had a mean age of 60 ± 13 years, 28% women, 36% African Americans, 56% ischaemic cardiomyopathy, and 29 ± 16% Seattle HF risk score (SHFS) 5-year predicted mortality. Over 45 ± 24 months, there were 134 appropriate shocks and 166 deaths. After adjusting for 30 exposures, the hazard ratios (comparing the 5th to 1st quintile of EntropyXQT) for primary and secondary outcomes were 3.29 (95% CI 1.74-6.21) and 2.28 (1.53-3.41), respectively. Addition of EntropyXQT to a model comprised of the exposures or SHFS significantly increased net reclassification and the ROC curve area. CONCLUSIONS EntropyXQT measured during ICD implantation strongly and independently predicts appropriate shock and all-cause mortality over follow-up. EntropyXQT complements conventional risk predictors and has the potential for broad clinical application.
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Affiliation(s)
- Deeptankar DeMazumder
- Division of Cardiology, Johns Hopkins University School of Medicine, 720 North Rutland Avenue, Ross 844, Baltimore, MD 21205, USA
| | - Worawan B Limpitikul
- Division of Cardiology, Johns Hopkins University School of Medicine, 720 North Rutland Avenue, Ross 844, Baltimore, MD 21205, USA
| | - Miguel Dorante
- Division of Cardiology, Johns Hopkins University School of Medicine, 720 North Rutland Avenue, Ross 844, Baltimore, MD 21205, USA
| | - Swati Dey
- Division of Cardiology, Johns Hopkins University School of Medicine, 720 North Rutland Avenue, Ross 844, Baltimore, MD 21205, USA
| | - Bhasha Mukhopadhyay
- Division of Cardiology, Johns Hopkins University School of Medicine, 720 North Rutland Avenue, Ross 844, Baltimore, MD 21205, USA
| | - Yiyi Zhang
- Department of Epidemiology and Welch Center for Prevention, Epidemiology, and Clinical Research, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - J Randall Moorman
- Division of Cardiology, University of Virginia, Charlottesville, VA, USA
| | - Alan Cheng
- Division of Cardiology, Johns Hopkins University School of Medicine, 720 North Rutland Avenue, Ross 844, Baltimore, MD 21205, USA
| | - Ronald D Berger
- Division of Cardiology, Johns Hopkins University School of Medicine, 720 North Rutland Avenue, Ross 844, Baltimore, MD 21205, USA
| | - Eliseo Guallar
- Department of Epidemiology and Welch Center for Prevention, Epidemiology, and Clinical Research, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Steven R Jones
- Division of Cardiology, Johns Hopkins University School of Medicine, 720 North Rutland Avenue, Ross 844, Baltimore, MD 21205, USA
| | - Gordon F Tomaselli
- Division of Cardiology, Johns Hopkins University School of Medicine, 720 North Rutland Avenue, Ross 844, Baltimore, MD 21205, USA
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18
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Carpenter RE, Emery SJ, Uzun O, Rassi D, Lewis MJ. Influence of antenatal physical exercise on heart rate variability and QT variability. J Matern Fetal Neonatal Med 2016; 30:79-84. [PMID: 27023345 DOI: 10.3109/14767058.2016.1163541] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
OBJECTIVE We sought to characterise the influence of an antenatal exercise programme on ECG-derived cardiac variables. METHODS Fifity-one healthy pregnant women were recruited and randomly assigned (2 × 2×2 design) to an exercise group or a control group. Exercising groups attended weekly classes from the 20th week of pregnancy onwards. Cardiovascular assessments (heart rate variabiliy (HRV), QT, and the QT variability index (QTVI)) were performed at 12-16, 26-28, 34-36 weeks and 12 weeks following birth, during supine rest and exercise conditions. RESULTS Advancing gestation was associated with an increased maternal heart rate (p = 0.001), shorter QT interval (p = 0.003), diminished HRV (p = 0.002) and increased QTVI (p = 0.002). Each of these changes was reversed within 12 weeks postpartum (p < 0.004). The Exercise group displayed exaggerated changes for all variables (except QT) but only during supine rest in the third trimester (p < 0.029). CONCLUSION Advancing gestation is associated with a shift in HRV/QTVI towards values that have been associated with an elevated risk of arrhythmia. A 20-week exercise programme undertaken between mid and late pregnancy exaggerated these changes during rest in the third trimester of pregnancy.
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Affiliation(s)
- R E Carpenter
- a College of Engineering, Swansea University , Swansea , UK
| | - S J Emery
- b Department of Gynaecology , Singleton Hospital , Swansea , UK
| | - O Uzun
- c Department of Paediatric Cardiology , University Hospital of Wales , Cardiff , UK , and
| | - D Rassi
- d College of Health and Human Sciences, Swansea University , Swansea , UK
| | - M J Lewis
- a College of Engineering, Swansea University , Swansea , UK
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19
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Fister M, Mikuz U, Starc V, Vrtovec B, Haddad F. Heart rate-guided, but not dose-guided titration of beta blockers stabilizes ventricular repolarization in patients with chronic heart failure. J Electrocardiol 2016; 49:579-86. [PMID: 26875428 DOI: 10.1016/j.jelectrocard.2016.01.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2015] [Indexed: 10/22/2022]
Abstract
AIMS We compared the effects of heart rate-guided and dose-guided beta-blocker titration strategies on QT variability in patients with chronic heart failure (CHF). METHODS In a prospective study we recorded 5-minute resting high-resolution ECGs (HRECG) in 100 patients with CHF and measured heart rate (HR) and ventricular repolarization by QT variability index (QTVI). In a subgroup of patients not reaching target HR (<70bpm) we uptitrated beta blockers and repeated HRECG measurements 3months thereafter. RESULTS Target HR was present in 46 patients (group A), and in 54 patients HR was above target (group B). The groups did not differ in age, gender, NYHA class, NT pro-BNP, creatinine, or beta blocker dose. Patients in group A displayed significantly lower QTVI than patients in group B (-1.25±0.55 vs. -1.52±0.42, P=0.013). When uptitrating beta-blockers we found a decrease in HR (from 91±15bpm to 71±15bpm, P<0.001), NTpro BNP levels (from 4474±3878pg/ml to 3042±2566pg/ml, P=0.024), and NYHA class (from 3.0±0.8 to 2.5±0.7, P=0.006). With beta-blocker uptitration QTVI decreased in 10 of 24 patients (42%). In these patients HR decreased more than in the remaining cohort (-25±20bpm vs. -15±17bpm, P=0.017). On multivariate analysis, the presence of target HR was a predictor of QTVI decrease (P=0.017), but beta-blocker dose was not. CONCLUSIONS In patients with CHF treated by beta-blockers, changes in QT variability appear to occur in parallel with changes of heart rate. This suggests that heart rate-guided titration of beta-blockers may be associated with decreased risk of sudden cardiac death.
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Affiliation(s)
- Misa Fister
- Advanced Heart Failure and Transplantation Center, UMC, Ljubljana, Slovenia
| | - Ursa Mikuz
- Advanced Heart Failure and Transplantation Center, UMC, Ljubljana, Slovenia
| | - Vito Starc
- Institute of Physiology, Ljubljana University School of Medicine, Ljubljana, Slovenia
| | - Bojan Vrtovec
- Advanced Heart Failure and Transplantation Center, UMC, Ljubljana, Slovenia; Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA, USA.
| | - François Haddad
- Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA, USA
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20
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Abstract
Background Increased variability of QT interval (QTV) has been linked to arrhythmias in animal experiments and multiple clinical situations. Congenital long QT syndrome (LQTS), a pure repolarization disease, may provide important information on the relationship between delayed repolarization and QTV. Methods and Results Twenty‐four‐hour Holter monitor tracings from 78 genotyped congenital LQTS patients (52 females; 51 LQT1, 23 LQT2, 2 LQT5, 2 JLN, 27 symptomatic; age, 35.2±12.3 years) were evaluated with computer‐assisted annotation of RR and QT intervals. Several models of RR‐QT relationship were tested in all patients. A model assuming exponential decrease of past RR interval contributions to QT duration with 60‐second time constant provided the best data fit. This model was used to calculate QTc and residual “intrinsic” QTV, which cannot be explained by heart rate change. The intrinsic QTV was higher in patients with long QTc (r=0.68; P<10−4), and in LQT2 than in LQT1/5 patients (5.65±1.28 vs 4.46±0.82; P<0.0002). Both QTc and intrinsic QTV were similar in symptomatic and asymptomatic patients (467±52 vs 459±53 ms and 5.10±1.19 vs 4.74±1.09, respectively). Conclusions In LQTS patients, QT interval adaptation to heart rate changes occurs with time constant ≈60 seconds, similar to results reported in control subjects. Intrinsic QTV correlates with the degree of repolarization delay and might reflect action potential instability observed in animal models of LQTS.
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Affiliation(s)
- Srikanth Seethala
- Scripps Clinic, San Diego, CA (S.S.) University of Tennessee, College of Medicine, Chattanooga, TN
| | | | | | - Margareth Ribe
- Department of Cardiology, Center for Cardiological Innovation and Institute for Surgical Research, Oslo University Hospital, Rikshospitalet, Oslo, Norway (M.R., K.H.H.)
| | - Kristina H Haugaa
- Department of Cardiology, Center for Cardiological Innovation and Institute for Surgical Research, Oslo University Hospital, Rikshospitalet, Oslo, Norway (M.R., K.H.H.) University of Oslo, Norway (K.H.H.)
| | - Jan Němec
- University of Pittsburgh, PA (P.S., J.)
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21
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Ramaswamy S, Selvaraj V, Driscoll D, Madabushi JS, Bhatia SC, Yeragani V. Effects of Escitalopram on Autonomic Function in Posttraumatic Stress Disorder Among Veterans of Operations Enduring Freedom and Iraqi Freedom (OEF/OIF). Innov Clin Neurosci 2015; 12:13-9. [PMID: 26155373 PMCID: PMC4479359] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
OBJECTIVE Posttraumatic stress disorder is a chronic, debilitating condition that has become a growing concern among combat veterans. Previous research suggests that posttraumatic stress disorder disrupts normal autonomic responding and may increase the risk of cardiovascular disease and mortality. Measures of heart rate variability and QT interval variability have been used extensively to characterize sympathetic and parasympathetic influences on heart rate in a variety of psychiatric populations. The objective of this study was to better understand the effects of pharmacological treatment on autonomic reactivity in posttraumatic stress disorder. DESIGN A 12-week, Phase IV, prospective, open-label trial of escitalopram in veterans with combat-related posttraumatic stress disorder and comorbid depression. SETTING An outpatient mental health clinic at a Veterans Affairs Medical Center. PARTICIPANTS Eleven male veterans of Operations Enduring Freedom and Iraqi Freedom diagnosed with posttraumatic stress disorder and comorbid depression. MEASUREMENTS Autonomic reactivity was measured by examining heart rate variability and QT interval variability. Treatment safety and efficacy were also evaluated pre- and post-treatment. RESULTS We observed a reduction in posttraumatic stress disorder and depression symptoms from pre- to post-treatment, and escitalopram was generally well tolerated in our sample. In addition, we observed a decrease in high frequency heart rate variability and an increase in QT variability, indicating a reduction in cardiac vagal function and heightened sympathetic activation. CONCLUSION These findings suggest that escitalopram treatment in patients with posttraumatic stress disorder and depression can trigger changes in autonomic reactivity that may adversely impact cardiovascular health.
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Affiliation(s)
- Sriram Ramaswamy
- Drs. Ramaswamy, Driscoll, and Bhatia are with the Nebraska Western Iowa Veterans Affairs Healthcare System and Creighton University, Omaha, Nebraska; Dr. Selvaraj is with Creighton University, Omaha, Nebraska; Dr. Madabushi is with Baptist Health System, Birmingham, Alabama; and Dr. Yeragani is with Wayne State University School of Medicine, Detroit, Michigan, and the University of Alberta, Edmonton, Canada
| | - Vithyalakshmi Selvaraj
- Drs. Ramaswamy, Driscoll, and Bhatia are with the Nebraska Western Iowa Veterans Affairs Healthcare System and Creighton University, Omaha, Nebraska; Dr. Selvaraj is with Creighton University, Omaha, Nebraska; Dr. Madabushi is with Baptist Health System, Birmingham, Alabama; and Dr. Yeragani is with Wayne State University School of Medicine, Detroit, Michigan, and the University of Alberta, Edmonton, Canada
| | - David Driscoll
- Drs. Ramaswamy, Driscoll, and Bhatia are with the Nebraska Western Iowa Veterans Affairs Healthcare System and Creighton University, Omaha, Nebraska; Dr. Selvaraj is with Creighton University, Omaha, Nebraska; Dr. Madabushi is with Baptist Health System, Birmingham, Alabama; and Dr. Yeragani is with Wayne State University School of Medicine, Detroit, Michigan, and the University of Alberta, Edmonton, Canada
| | - Jayakrishna S Madabushi
- Drs. Ramaswamy, Driscoll, and Bhatia are with the Nebraska Western Iowa Veterans Affairs Healthcare System and Creighton University, Omaha, Nebraska; Dr. Selvaraj is with Creighton University, Omaha, Nebraska; Dr. Madabushi is with Baptist Health System, Birmingham, Alabama; and Dr. Yeragani is with Wayne State University School of Medicine, Detroit, Michigan, and the University of Alberta, Edmonton, Canada
| | - Subhash C Bhatia
- Drs. Ramaswamy, Driscoll, and Bhatia are with the Nebraska Western Iowa Veterans Affairs Healthcare System and Creighton University, Omaha, Nebraska; Dr. Selvaraj is with Creighton University, Omaha, Nebraska; Dr. Madabushi is with Baptist Health System, Birmingham, Alabama; and Dr. Yeragani is with Wayne State University School of Medicine, Detroit, Michigan, and the University of Alberta, Edmonton, Canada
| | - Vikram Yeragani
- Drs. Ramaswamy, Driscoll, and Bhatia are with the Nebraska Western Iowa Veterans Affairs Healthcare System and Creighton University, Omaha, Nebraska; Dr. Selvaraj is with Creighton University, Omaha, Nebraska; Dr. Madabushi is with Baptist Health System, Birmingham, Alabama; and Dr. Yeragani is with Wayne State University School of Medicine, Detroit, Michigan, and the University of Alberta, Edmonton, Canada
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Porta A, Girardengo G, Bari V, George AL, Brink PA, Goosen A, Crotti L, Schwartz PJ. Autonomic control of heart rate and QT interval variability influences arrhythmic risk in long QT syndrome type 1. J Am Coll Cardiol 2015; 65:367-374. [PMID: 25634836 DOI: 10.1016/j.jacc.2014.11.015] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Revised: 10/08/2014] [Accepted: 11/04/2014] [Indexed: 11/27/2022]
Abstract
BACKGROUND A puzzling feature of the long QT syndrome (LQTS) is that family members carrying the same mutation often have divergent symptoms and clinical outcomes. OBJECTIVES This study tested the hypothesis that vagal and sympathetic control, as assessed by spectral analysis of spontaneous beat-to-beat variability of RR and QT intervals from standard 24-h electrocardiogram Holter recordings, could modulate the severity of LQTS type 1 (LQT1) in 46 members of a South-African LQT1 founder population carrying the clinically severe KCNQ1 A341V mutation. METHODS Nonmutation carriers (NMCs) (n = 14) were compared with mutation carriers (MCs) (n = 32), 22 with and 10 without major symptoms. We assessed the effect of circadian rhythm and beta-blocker therapy over traditional time and frequency domain RR and QT variability indexes. RESULTS The asymptomatic MCs differed significantly from the symptomatic MCs and from NMCs in less vagal control of heart rate and more reactive sympathetic modulation of the QT interval, particularly during daytime when arrhythmia risk for patients with LQT1 is greatest. CONCLUSIONS The present data identified an additional factor contributing to the differential arrhythmic risk among patients with LQT1 carrying the same mutation. A healthy autonomic control confers a high risk, whereas patients with higher sympathetic control of the QT interval and reduced vagal control of heart rate are at lower risk. This differential "autonomic make-up," likely under genetic control, will allow refinement of risk stratification within families with LQTS, leading to more targeted management.
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Affiliation(s)
- Alberto Porta
- Department of Biomedical Sciences for Health, University of Milan, Milan, Italy; IRCCS Galeazzi Orthopedic Institute, Milan, Italy.
| | - Giulia Girardengo
- Center for Cardiac Arrhythmias of Genetic Origin and Laboratory of Cardiovascular Genetics, IRCCS Istituto Auxologico Italiano, Milan, Italy
| | - Vlasta Bari
- Department of Cardiothoracic, Vascular Anesthesia and Intensive Care, IRCCS Policlinico San Donato, Milan, Italy
| | - Alfred L George
- Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, Illinois; Departments of Medicine and Pharmacology, Vanderbilt University, Nashville, Tennessee
| | - Paul A Brink
- Department of Internal Medicine, University of Stellenbosch, Stellenbosch, South Africa
| | - Althea Goosen
- Department of Internal Medicine, University of Stellenbosch, Stellenbosch, South Africa
| | - Lia Crotti
- Center for Cardiac Arrhythmias of Genetic Origin and Laboratory of Cardiovascular Genetics, IRCCS Istituto Auxologico Italiano, Milan, Italy; Department of Molecular Medicine, University of Pavia, Pavia, Italy
| | - Peter J Schwartz
- Center for Cardiac Arrhythmias of Genetic Origin and Laboratory of Cardiovascular Genetics, IRCCS Istituto Auxologico Italiano, Milan, Italy
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23
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Mikuz U, Poglajen G, Fister M, Starc V, Wu JC, Hsia H, Haddad F, Vrtovec B. The presence of electromechanical mismatch in nonischemic dilated cardiomyopathy is associated with ventricular repolarization instability. J Card Fail 2014; 20:891-8. [PMID: 25305502 DOI: 10.1016/j.cardfail.2014.10.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2014] [Revised: 09/29/2014] [Accepted: 10/01/2014] [Indexed: 10/24/2022]
Abstract
BACKGROUND We analyzed electromechanical mismatch (EMM) and its relationship to ventricular repolarization in patients with nonischemic dilated cardiomyopathy (DCM). METHODS AND RESULTS In 39 DCM patients with left ventricular ejection fraction (LVEF) <40% and New York Heart Association functional class ≥III, electroanatomic mapping was used to quantify areas of EMM. High-resolution electrocardiograph was used to measure heart rate variability (HRV) and QT variability index (QTVI). EMM was present in 22 patients (56%, group 1), whereas 17 patients presented no mismatched segments (44%, group 2). The groups did not differ in age (56 ± 10 years in group 1 vs 57 ± 7 years in group 2; P = .82), sex (male: 82% vs 94%; P = .40), LVEF (27 ± 8% vs 25 ± 6%; P = .18), or N-terminal pro-B-type natriuretic peptide (2,350 pg/mL vs 2,831 pg/mL; P = .32). Although heart rate and HRV were similar in both groups (rate: 80 ± 20 beats/min in group 1 vs 74 ± 19 beats/min in group 2 [P = .47]; standard deviation of normal-to normal RR intervals: 106 ± 79 vs 88 ± 115 [P = .61]), we found significantly higher QTVI values in patients from group 1 (-1.15 ± 0.46 vs -1.62 ± 0.51 in group 2; P = .005). In patients with implantable cardioverter-defibrillators, ventricular arrhythmias recorded ≤1 year before enrollment were more frequent in group 1 than in group 2 (58% vs 13%; P = .02). CONCLUSIONS EMM is present in a majority of patients with DCM and is associated with ventricular repolarization instability.
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Affiliation(s)
- Ursa Mikuz
- Advanced Heart Failure and Transplantation Center, Department of Cardiology, University Medical Center, Ljubljana, Slovenia
| | - Gregor Poglajen
- Advanced Heart Failure and Transplantation Center, Department of Cardiology, University Medical Center, Ljubljana, Slovenia
| | - Misa Fister
- Department of Intensive Care Medicine, University Medical Center, Ljubljana, Slovenia
| | - Vito Starc
- Institute of Physiology, University of Ljubljana School of Medicine, Ljubljana, Slovenia
| | - Joseph C Wu
- Stanford Cardiovascular Institute, Stanford University School of Medicine, Stanford, California
| | - Henry Hsia
- Stanford Cardiovascular Institute, Stanford University School of Medicine, Stanford, California
| | - François Haddad
- Stanford Cardiovascular Institute, Stanford University School of Medicine, Stanford, California
| | - Bojan Vrtovec
- Advanced Heart Failure and Transplantation Center, Department of Cardiology, University Medical Center, Ljubljana, Slovenia; Stanford Cardiovascular Institute, Stanford University School of Medicine, Stanford, California.
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24
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Platiša MM, Gal V, Nestorović Z, Gojković-Bukarica L. Quantification of the acute effect of a low dose of red wine by nonlinear measures of RR and QT interval series in healthy subjects. Comput Biol Med 2014; 53:291-6. [PMID: 25194258 DOI: 10.1016/j.compbiomed.2014.08.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2014] [Revised: 07/24/2014] [Accepted: 08/12/2014] [Indexed: 11/27/2022]
Abstract
The measures of nonlinear properties of RR interval and QT interval time series are sensitive to physiologically- or pathologically-induced complexity/regularity changes, but were not used to estimate the effect of alcohol intake. We wanted to examine the potential of these measures to quantify the acute effect of a low dose of red wine in healthy subjects. In separate experiments, fourteen young volunteers drank 200ml of red wine and a control drink with equal concentration of ethanol. ECG in supine position was recorded 20min before and 60min after drink intake. RR interval and QT interval series were extracted from ECG and we calculated variability, scaling exponents (α1 and α2) and sample entropy (SampEn) for both series. Systolic and diastolic blood pressures (BP) were measured every 10min. The immediate effect of both the drinks was equal: HR, BP and QT variability exhibited a sudden increase and then a decrease. However, the prolonged effect of wine and the control drink was different. Wine decreased both BP (p<0.05) and reduced complexity of RR and QT series (increased scaling exponents and decreased SampEn). The control drink prolonged QT and RR intervals (p<0.05). These results point out that the nonlinear properties of RR and QT interval series could be used to differentiate the effect of wine and ethanol. Changes in RR and QT interval series induced by a low dose of red wine are more detectable by methods that quantify the structure of the series than by methods that quantify their variability.
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Affiliation(s)
- Mirjana M Platiša
- Institute of Biophysics, Faculty of Medicine, University of Belgrade, Belgrade, Serbia.
| | - Vera Gal
- Institute of Biophysics, Faculty of Medicine, University of Belgrade, Belgrade, Serbia
| | - Zorica Nestorović
- Institute of Biophysics, Faculty of Medicine, University of Belgrade, Belgrade, Serbia
| | - Ljiljana Gojković-Bukarica
- Department of Pharmacology, Clinical Pharmacology and Toxicology, Faculty of Medicine, University of Belgrade, Belgrade, Serbia
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25
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Abstract
The International Conference on Harmonization of Technical Requirements for Registration of Pharmaceuticals for Human Use (ICH) Guideline E14 recommends 'Thorough QT Study' as a standard assessment of drug-induced QT interval prolongation. At the same time, the value of drug-induced QTc prolongation as a surrogate marker for risk of life-threatening polymorphic ventricular tachycardia known as torsades des pointes remains controversial. Beat-to-beat variability of QT interval was recently proposed as an alternative metric. The following review addresses mechanisms of beat-to-beat QT variability, methods of QT interval variability measurements, and its prognostic value in clinical studies.
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Affiliation(s)
- Larisa G Tereshchenko
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Ronald D Berger
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Carnegie 592, 600 N. Wolfe St., Baltimore, MD 21287, USA
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26
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Abstract
The QT Variability Index (QTVI) is a non-invasive measure of repolarization lability that has been applied to a wide variety of subjects with cardiovascular disease. It is a ratio of normalized QT variability to normalized heart rate variability, and therefore includes an assessment of autonomic nervous system tone. The approach assesses beat-to-beat variability in the duration of the QT and U wave in conventional surface electrocardiographic recordings, as well as determines the heart rate variability (HRV) from the same recording. As opposed to T wave alternans, QTVI assesses variance in repolarization at all frequencies. Nineteen studies have published data on QTVI in healthy individuals, while 20 have evaluated its performance in cohorts with cardiovascular disease. Six studies have assessed the utility of QTVI in predicting VT/VF, cardiac arrest, or cardiovascular death. A prospective study utilizing QTVI to determine therapy allocation has not been performed, and therefore the final determination of the value of the metric awaits definitive exploration.
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Affiliation(s)
- Craig P Dobson
- Department of Medicine, Division of Cardiology, Uniformed Services University of the Health Sciences, Bethesda, MD, USA; Walter Reed National Military Medical Center, Bethesda, MD, USA
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27
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Nayyar S, Roberts-Thomson KC, Hasan MA, Sullivan T, Harrington J, Sanders P, Baumert M. Autonomic modulation of repolarization instability in patients with heart failure prone to ventricular tachycardia. Am J Physiol Heart Circ Physiol 2013; 305:H1181-8. [PMID: 23934852 DOI: 10.1152/ajpheart.00448.2013] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
QT variability (QTV) signifies repolarization lability, and increased QTV is a risk predictor for sudden cardiac death. The aim of the present study was to investigate the role of autonomic nervous system activity on QTV. This study was performed in 29 subjects: 10 heart failure (HF) patients with spontaneous ventricular tachycardia [HFVT(+)], 10 HF patients without spontaneous VT [HFVT(-)], and 9 subjects with structurally normal hearts (HNorm). The beat-to-beat QT interval was measured on 3-min records of surface ECGs at baseline and during interventions (atrial pacing and esmolol, isoprenaline, and atropine infusion). Variability in QT intervals was expressed as the SD of all QT intervals (SDQT). The ratio of the SDQT to SD of RR intervals (SDRR) was calculated as an index of QTV normalized to heart rate variability. There was a trend toward a higher baseline SDQT-to-SDRR ratio in the HFVT(+) group compared with the HFVT(-) and HNorm groups (P = 0.09). SDQT increased significantly in the HFVT(+) and HFVT(-) groups compared with the HNorm group during fixed-rate atrial pacing (P = 0.008). Compared with baseline, isoprenaline infusion increased SDQT in HNorm subjects (P = 0.02) but not in HF patients. SDQT remained elevated in the HFVT(+) group relative to the HNorm group despite acute β-adrenoceptor blockade with esmolol (P = 0.02). In conclusion, patients with HF and spontaneous VT have larger fluctuations in beat-to-beat QT intervals. This appears to be a genuine effect that is not solely a consequence of heart rate variation. The effect of acute autonomic nervous system modulation on QTV appears to be limited in HF patients.
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Affiliation(s)
- Sachin Nayyar
- Centre for Heart Rhythm Disorders, The University of Adelaide and Royal Adelaide Hospital, Adelaide, South Australia, Australia
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28
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Piccirillo G, Moscucci F, Pascucci M, Pappadà MA, D'Alessandro G, Rossi P, Quaglione R, Di Barba D, Barillà F, Magrì D. Influence of aging and chronic heart failure on temporal dispersion of myocardial repolarization. Clin Interv Aging 2013; 8:293-300. [PMID: 23662051 PMCID: PMC3646393 DOI: 10.2147/cia.s41879] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2013] [Indexed: 01/01/2023] Open
Abstract
Background and purpose: QT and Tpeak-Tend (Te) intervals are associated with sudden cardiac death
in patients with chronic heart failure (CHF). We studied age-dependent influence on short-term
temporal dispersion of these two variables in patients with postischemic CHF. Method: We grouped 75 CHF and 53 healthy control subjects into three age subsets: ≤50 years,
>50 years and ≤65 years, and >65 years. We then calculated the following
indices: QT and Te variability index (QTVI and TeVI), the ratio between the short-term variability
(STV) of QT or Te, and the STV of resting rate (RR) (QT/RR STV and Te/RR STV). Results: In all different age subgroups, patients with CHF showed a higher level of QTVI than age-matched
control subjects (≤50 years: P < 0.0001; >50 years and
≤65 years: P < 0.05; >65 years: P
< 0.05). Patients with CHF < 50 years old also had all repolarization variability
indices higher than normal age-matched controls (TeVI, P < 0.05; QT/RR STV,
P < 0.05; Te/RR STV, P < 0.05), whereas we did not
find any difference between the two older classes of subjects. Both QTVI
(r2: 0.178, P < 0.05) and TeVI
(r2: 0.433, P < 0.001) were positively related
to age in normal subjects, even if the first correlation was weaker than the second one. Conclusion: Our data showed that QTVI could be used in all ages to evaluate repolarization temporal
liability, whereas the other indices are deeply influenced by age. Probably, the age-dependent
increase in QTVI was more influenced by a reduction of RR variability reported in older normal
subjects.
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Affiliation(s)
- Gianfranco Piccirillo
- Department of Cardiovascular, Respiratory, Nephrological and Geriatric Sciences, Policlinico Umberto I, "Sapienza" University of Rome, Rome, Italy.
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