Frequency of sudden cardiac death and profiles of risk

Sudden cardiac arrest prediction via deep learning electrocardiogram analysis

Aims

Sudden cardiac arrest (SCA) is a commonly fatal event that often occurs without prior indications. To improve outcomes and enable preventative strategies, the electrocardiogram (ECG) in conjunction with deep learning was explored as a potential screening tool.

Methods and results

A publicly available data set containing 10 s of 12-lead ECGs from individuals who did and did not have an SCA, information about time from ECG to arrest, and age and sex was utilized for analysis to individually predict SCA or not using deep convolution neural network models. The base model that included age and sex, ECGs within 1 day prior to arrest, and data sampled from windows of 720 ms around the R-waves from 221 individuals with SCA and 1046 controls had an area under the receiver operating characteristic curve of 0.77. With sensitivity set at 95%, base model specificity was 31%, which is not clinically applicable. Gradient-weighted class activation mapping showed that the model mostly relied on the QRS complex to make predictions. However, models with ECGs recorded between 1 day to 1 month and 1 month to 1 year prior to arrest demonstrated predictive capabilities.

Conclusion

Deep learning models processing ECG data are a promising means of screening for SCA, and this method explains differences in SCAs due to age and sex. Model performance improved when ECGs were nearer in time to SCAs, although ECG data up to a year prior had predictive value. Sudden cardiac arrest prediction was more dependent upon QRS complex data compared to other ECG segments.

The Impact of QT-Prolonging Medications and Drug-Drug Interactions on QTc Interval Prolongation in Hospitalized Patients: A Case-Crossover Study

Researchers have studied potential corrected QT interval (QTc) prolongation from drug-drug interactions (DDIs), raising unresolved questions about their real-world impact. This retrospective case-crossover study investigated the effects of QT-prolonging drugs and DDIs on QTc prolongation in hospitalized patients aged 45 years and above. The cohort comprised patients who had multiple hospitalizations and developed QTc prolongation (QTc > 500 ms or an increase of >60 ms from baseline) at least 24 hours after admission between 2011 and 2019. Conditional logistic regression compared drug exposure between hospitalizations with QTc prolongation (case window) and those without (reference window). Among 2,276 patients (mean age 71; 43.8% female), the use of QT-prolonging drugs significantly increased the risk of QTc prolongation (odds ratio: 2.42 (95% confidence interval: 1.95-3.02)). The risk was higher with drugs of "known risks" (OR: 3.78 (2.91-4.90)) and "conditional risk" (OR: 2.08 (1.65-2.62)). DDIs, particularly involving multiple "known risk" drugs (OR: 7.86 (4.96-12.45)), strong cytochrome P450 enzyme inhibitors (OR: 5.57 (2.75-11.30)), or the concurrent use of ≥4 QT-prolonging drugs with any risk (OR: 5.28 (3.96-7.03)) substantially increased the risk. Cautious prescribing for patients with multiple risk factors is important to minimize the likelihood of QTc prolongation. However, when considering enhanced monitoring or drug choices, it is crucial to carefully evaluate the overall risk of QT prolongation against the benefits of treatment to ensure optimal patient care.

Chaos control in cardiac dynamics: terminating chaotic states with local minima pacing

Current treatments of cardiac arrhythmias like ventricular fibrillation involve the application of a high-energy electric shock, that induces significant electrical currents in the myocardium and therefore involves severe side effects like possible tissue damage and post-traumatic stress. Using numerical simulations on four different models of 2D excitable media, this study demonstrates that low energy pulses applied shortly after local minima in the mean value of the transmembrane potential provide high success rates. We evaluate the performance of this approach for ten initial conditions of each model, ten spatially different stimuli, and different shock amplitudes. The investigated models of 2D excitable media cover a broad range of dominant frequencies and number of phase singularities, which demonstrates, that our findings are not limited to a specific kind of model or parameterization of it. Thus, we propose a method that incorporates the dynamics of the underlying system, even during pacing, and solely relies on a scalar observable, which is easily measurable in numerical simulations.

Templer's death anxiety scale on the relationship between white coat hypertension and anxiety: A cross-sectional study

The relationship between white coat hypertension (WCH) and anxiety remains not fully elucidated. This study aims to investigate the correlation between WCH and Templer's Death Anxiety Scale (T-DAS) questionnaire. Asymptomatic individuals with a familial history of sudden cardiac death or acute myocardial infarction within the last year, who presented at our cardiology outpatient clinic, were enrolled in this prospective, single-center, cross-sectional study. Among those with elevated blood pressure in the outpatient clinic setting, participants were categorized into normotensive and WCH groups through 24-hour ambulatory blood pressure monitoring. Demographic features, laboratory parameters, and T-DAS scores were documented. Logistic regression and sensitivity analyses were conducted to ascertain WCH occurrence. Among 324 consecutive participants, 90 were diagnosed with WCH. T-DAS scores were significantly elevated in the WCH subgroup, particularly among those seeking early medical attention following bereavement. Multivariable logistic regression highlighted gender, BMI, heart rate, T-DAS, and admission time as independent correlates of WCH. Significantly, T-DAS exhibited the third most substantial contribution to the regression analysis, following admission time and heart rate. The multivariable logistic regression analysis incorporating T-DAS exhibited high robustness, discrimination, fit, and calibration, with a Brier score of 0.106, adjusted R2 of 0.576, and C-statistic of 0.905 (95% CI: 0.871-0.940, p < 0.001). T-DAS, with a threshold of >8, demonstrated 48% sensitivity and 90% specificity in detecting WCH. Additionally, decision curve analysis verified that the model including T-DAS offers a net benefit in detecting WCH. This study unveils a potential association between WCH and death anxiety.

Feasibility and limitations of deep learning-based coronary calcium scoring in PET-CT: a comparison with coronary calcium score CT

OBJECTIVE

This study aimed to determine the feasibility and limitations of deep learning-based coronary calcium scoring using positron emission tomography-computed tomography (PET-CT) in comparison with coronary calcium scoring using ECG-gated non-contrast-enhanced cardiac computed tomography (CaCT).

MATERIALS AND METHODS

A total of 215 individuals who underwent both CaCT and PET-CT were enrolled in this retrospective study. The Agatston method was used to calculate the coronary artery calcium scores (CACS) from CaCT, PET-CT(reader), and PET-CT(AI) to analyse the effect of using different modalities and AI-based software on CACS measurement. The total CACS and CACS classified according to the CAC-DRS guidelines were compared between the three sets of CACS. The differences, correlation coefficients, intraclass coefficients (ICC), and concordance rates were analysed. Statistical significance was set at p < 0.05.

RESULTS

The correlation coefficient of the total CACS from CaCT and PET-CT(reader) was 0.837, PET-CT(reader) and PET-CT(AI) was 0.894, and CaCT and PET-CT(AI) was 0.768. The ICC of CACS from CaCT and PET-CT(reader) was 0.911, PET-CT(reader) and PET-CT(AI) was 0.958, and CaCT and PET-CT(AI) was 0.842. The concordance rate between CaCT and PET-CT(AI) was 73.8%, with a false-negative rate of 37.3% and a false-positive rate of 4.4%. Age and male sex were associated with an increased misclassification rate.

CONCLUSIONS

Artificial intelligence-assisted CACS measurements in PET-CT showed comparable results to CACS in coronary calcium CT. However, the relatively high false-negative results and tendency to underestimate should be of concern.

CLINICAL RELEVANCE STATEMENT

Application of automated calcium scoring to PET-CT studies could potentially select patients at high risk of coronary artery disease from among cancer patients known to be susceptible to coronary artery disease and undergoing routine PET-CT scans.

KEY POINTS

• Cancer patients are susceptible to coronary disease, and PET-CT could be potentially used to calculate coronary artery calcium score (CACS). • Calcium scoring using artificial intelligence in PET-CT automatically provides CACS with high ICC to CACS in coronary calcium CT. • However, underestimation and false negatives of CACS calculation in PET-CT should be considered.

Asymptomatic paroxysmal ventricular standstill in an elderly male following revascularization of multivessel coronary disease: A case report and literature review

Ventricular standstill is a dangerous arrhythmia that requires prompt diagnosis and intervention, especially in patients with structural heart disease. Clinicians should recognize ventricular standstill as a complication of cardiac revascularization and be cognizant of asymptomatic cases necessitating intervention. Early evaluation to facilitate pacemaker implantation portends good outcomes in this patient subgroup.

[History of clinical electrophysiology in diagnosing and treatment monitoring of high ventricular vulnerability]

The paper presents the history of hope from 1980-1995 to predict the risk of sudden arrhythmic death using electrophysiologic techniques in individual patients. Even if this prediction seems possible in selected highly risk cohorts, many more patients will die in ventricular arrhythmia without fulfilling the criteria. Ultimately, high risk of sudden cardiac death can be predicted in selected patient groups, but not in the majority of patients at risk. It is a history of dashed hope.

Efficacy and prognostic impact of Pericarpium Trichosanthis injection combined with nicorandil for intractable angina pectoris in elderly patients: A retrospective study

BACKGROUND

Coronary artery disease (CAD) is a leading cause of global cardiovascular mortality. Refractory angina pectoris, a manifestation of CAD, requires effective drug treatments. Pericarpium Trichosanthis injection, a traditional Chinese medicine, improves cardiovascular symptoms, while nicorandil alleviates spasms and angina. Both have potential in treating CAD.

AIM

To investigate the therapeutic effects of combining Pericarpium Trichosanthis injection and nicorandil in elderly patients suffering from refractory angina caused by coronary heart disease.

METHODS

A retrospective analysis was conducted on the data of 130 patients diagnosed with refractory coronary heart disease. Based on the different treatment regimens administered during hospitalization, the patients were divided into a control group (58 cases) and a study group (72 cases). The control group received conventional treatment, which included aspirin, statins, and nitrate vasodilators. In addition to the conventional medication, the study group received a combination treatment of Pericarpium Trichosanthis injection and nicorandil.

RESULTS

After treatment, the study group showed significantly higher left ventricular ejection fraction and cardiac output, and lower brain natriuretic peptide and C-reactive protein levels compared to the control group. The study group also exhibited improvements in angina, quality of life, exercise endurance, and lipid profiles. Multivariate logistic regression analysis revealed a relationship of lipid levels and heart function with the combined treatment. Some patients in the study group experienced headaches during treatment, but no significant adverse reactions were observed. Follow-up showed that the treatment was well-tolerated, with no drug-related adverse reactions detected.

CONCLUSION

Combination of Pericarpium Trichosanthis injection and nicorandil is more effective than conventional treatment in improving symptoms and heart function in elderly patients with refractory angina pectoris.

Safety and efficacy of catheter ablation for ventricular tachycardia in elderly patients with structural heart disease: a systematic review and meta-analysis

PURPOSE

Data regarding the age-specific outcomes of VT ablation in patients with structural heart disease (SHD) are scarce. We performed a systematic review and meta-analysis to evaluate the outcomes of VT ablation in elderly vs. younger patients with SHD.

METHODS

MEDLINE/PubMed, Cochrane, and Google Scholar and references comparing VT ablation in elderly vs. younger patients were screened and studies included if matching inclusion and exclusion criteria.

RESULTS

Five retrospective studies enrolling 2778 SHD patients (868 elderly vs. 1910 younger) were included. Compared to younger subjects, the elderly showed similar results in terms of acute ablation success (OR 0.78, 95% CI 0.54-1.13, p = 0.189) and minor complications (OR 1.74, 95% CI 0.74-4.09, p = 0.205), a trend toward a higher risk of major complications (OR 2.30, 95% CI 0.83-6.40, p = 0.110) and significantly higher rates of all complications (OR 2.67, 95% CI 1.51-4.71, p = 0.001) and periprocedural mortality (OR 1.93, 95% CI 1.24-3.01, p = 0.004). At a mean follow-up of 18 months, elderly patients showed similar long-term VT recurrence rate (OR 1.02, 95% CI 0.85-1.22, p = 0.861) and higher all-cause mortality (OR 2.00, 95% CI 1.40-2.86, p < 0.001). In elderly patients, urgent VT ablation is associated with higher risk of major complications (beta = 0.06, p < 0.001) and periprocedural mortality (beta = 0.03, p = 0.029), while advanced age is associated with higher risk of major complications (beta = 0.29 with p = 0.009) and all complications + periprocedural mortality (beta = 0.17 with p = 0.037).

CONCLUSIONS

Compared to younger patients, VT ablation in elderly showed similar results in terms of acute ablation success and long-term VT recurrence rate with a significantly higher risk of all complications, periprocedural mortality, and long-term mortality, especially when the procedure is performed urgently and in the most aged patients. Large prospective multicenter randomized trials are required to confirm these findings.

Smartphone-activated volunteer responders and bystander defibrillation for out-of-hospital cardiac arrest in private homes and public locations

AIMS

To investigate the association between the arrival of smartphone-activated volunteer responders before the Emergency Medical Services (EMS) and bystander defibrillation in out-of-hospital cardiac arrest (OHCA) at home and public locations.

METHODS AND RESULTS

This is a retrospective study (1 September 2017-14 May 2019) from the Stockholm Region of Sweden and the Capital Region of Denmark. We included 1271 OHCAs, of which 1029 (81.0%) occurred in private homes and 242 (19.0%) in public locations. The main outcome was bystander defibrillation. At least one volunteer responder arrived before EMS in 381 (37.0%) of OHCAs at home and 84 (34.7%) in public. More patients received bystander defibrillation when a volunteer responder arrived before EMS at home (15.5 vs. 2.2%, P < 0.001) and in public locations (32.1 vs. 19.6%, P = 0.030). Similar results were found among the 361 patients with an initial shockable heart rhythm (52.7 vs. 11.5%, P < 0.001 at home and 60.0 vs. 37.8%, P = 0.025 in public). The standardized probability of receiving bystander defibrillation increased with longer EMS response times in private homes. The 30-day survival was not significantly higher when volunteer responders arrived before EMS (9.2 vs. 7.7% in private homes, P = 0.41; and 40.5 vs. 35.4% in public locations, P = 0.44).

CONCLUSION

Bystander defibrillation was significantly more common in private homes and public locations when a volunteer responder arrived before the EMS. The standardized probability of bystander defibrillation increased with longer EMS response times in private homes. Our findings support the activation of volunteer responders and suggest that volunteer responders could increase bystander defibrillation, particularly in private homes.

R-on-T and the initiation of reentry revisited: Integrating old and new concepts

Initiation of reentry requires 2 factors: (1) a triggering event, most commonly focal excitations such as premature ventricular complexes (PVCs); and (2) a vulnerable substrate with regional dispersion of refractoriness and/or excitability, such as occurs during the T wave of the electrocardiogram when some areas of the ventricle have repolarized and recovered excitability but others have not. When the R wave of a PVC coincides in time with the T wave of the previous beat, this timing can lead to unidirectional block and initiation of reentry, known as the R-on-T phenomenon. Classically, the PVC triggering reentry has been viewed as arising focally from 1 region and propagating into another region whose recovery is delayed, resulting in unidirectional conduction block and reentry initiation. However, more recent evidence indicates that PVCs also can arise from the T wave itself. In the latter case, the PVC initiating reentry is not a separate event from the T wave but rather is causally generated from the repolarization gradient that manifests as the T wave. We call the former an "R-to-T" mechanism and the latter an "R-from-T" mechanism, which are initiation mechanisms distinct from each other. Both are important components of the R-on-T phenomenon and need to be taken into account when designing antiarrhythmic strategies. Strategies targeting suppression of triggers alone or vulnerable substrate alone may be appropriate in some instances but not in others. Preventing R-from-T arrhythmias requires suppressing the underlying dynamic tissue instabilities responsible for producing both triggers and substrate vulnerability simultaneously. The same principles are likely to apply to supraventricular arrhythmias.

Characterizing arrhythmia using machine learning analysis of Ca2+ cycling in human cardiomyocytes

Accurate modeling of the heart electrophysiology to predict arrhythmia susceptibility remains a challenge. Current electrophysiological analyses are hypothesis-driven models drawing conclusions from changes in a small subset of electrophysiological parameters because of the difficulty of handling and understanding large datasets. Thus, we develop a framework to train machine learning classifiers to distinguish between healthy and arrhythmic cardiomyocytes using their calcium cycling properties. By training machine learning classifiers on a generated dataset containing a total of 3,003 healthy derived cardiomyocytes and their various arrhythmic states, the multi-class models achieved >90% accuracy in predicting arrhythmia presence and type. We also demonstrate that a binary classifier trained to distinguish cardiotoxic arrhythmia from healthy electrophysiology could determine the key biological changes associated with that specific arrhythmia. Therefore, machine learning algorithms can be used to characterize underlying arrhythmic patterns in samples to improve in vitro preclinical models and complement current in vivo systems.

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Calcium reporter enabled analysis of hPSC-derived CM electrophysiology

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Calcium electrophysiology can be decomposed to train machine learning classifiers

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Multi-class classifier distinguishes different forms of arrhythmias

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Binary-class classifiers identify key electrophysiological changes a priori

Temporal Changes in Beat-to-Beat Variability of Repolarization Predict Imminent Nonsustained Ventricular Tachycardia in Patients With Ischemic and Nonischemic Dilated Cardiomyopathy

Background

An increase in beat‐to‐beat variability of repolarization (BVR) predicts arrhythmia onset in experimental models, but its clinical translation is not well established. We investigated the temporal changes in BVR before nonsustained ventricular tachycardia (nsVT) in patients with implantable cardioverter defibrillator (ICD).

Methods and Results

Patients with nsVT on 24‐hour Holter before ICD implantation for ischemic cardiomyopathy (ischemic cardiomyopathy+nsVT, n=43) or dilated cardiomyopathy (dilated cardiomyopathy+nsVT, n=37), matched ICD candidates without nsVT (ischemic cardiomyopathy‐nsVT, n=29 and dilated cardiomyopathy‐nsVT, n=26), and patients without ICD without structural heart disease (n=50) were studied. Digital Holter recordings from these patients were analyzed using a modified fiducial segment averaging technique to detect the QT interval. The nsVT episodes were semi‐automatically identified and QT‐BVR was assessed 1‐, 5‐, and 30‐minutes before nsVT, and at rest (at 3:00 am). Resting BVR was higher in ICD patients compared with controls without structural heart disease. In ICD patients with nsVT, BVR increased significantly 1‐minute pre‐nsVT in ischemic cardiomyopathy (2.21±0.59 ms, versus 5 minutes pre‐nsVT: 1.78±0.50 ms, P<0.001) and dilated cardiomyopathy (2.09±0.57 ms, versus 5‐minutes pre‐nsVT: 1.58±0.51 ms, P<0.001), but not in patients without nsVT. In multivariable Cox regression analysis, pre‐nsVT BVR was a significant predictor for appropriate therapy during follow‐up.

Conclusions

Baseline BVR is elevated and temporal changes in BVR predict imminent nsVT events in patients with ICD independent of underlying cause. Real‐time BVR monitoring could be used to predict impending ventricular arrhythmia and allow preventive therapy to be incorporated into ICDs.

Kidney function and the risk of sudden cardiac death in the general population

Background

Chronic kidney disease increases sudden cardiac death (SCD) risk, but the association between kidney function and SCD in a general population is largely unknown. Therefore, we investigated the association between kidney function and SCD in a general middle-aged and elderly population.

Methods

We included individuals aged ≥45 years from a prospective population-based cohort study. The association between kidney function assessments [estimated glomerular filtration rate based on serum creatinine (eGFRcreat), cystatin C (eGFRcys) or both (eGFRcreat-cys)] and SCD was investigated using Cox proportional-hazards and joint models. Absolute 10-year risks were computed using competing risk analyses. Mediation analyses were performed using a four-way decomposition method.

Results

We included 9687 participants (median follow-up 8.9 years; mean age 65.3 years; 56.7% women; 243 SCD cases). Lower eGFRcys and eGFRcreat-cys were associated with increased SCD risk [hazard ratio (HR) 1.23, 95% confidence interval (CI) 1.12–1.34 and HR 1.17, 95% CI 1.06–1.29, per 10 mL/min/1.73 m² eGFR decrease]. A significant trend (P = 0.001) across eGFRcys categories was found, with an HR of 2.11 (95% CI 1.19–3.74) for eGFRcys <60 compared with eGFRcys >90 mL/min/1.73 m². Comparing eGFRcys of 90 to 60 mL/min/1.73 m², absolute 10-year risk increased from 1.0% to 2.5%. Identified subgroups at increased risk included older participants and participants with atrial fibrillation. The associations were not mediated by coronary heart disease, hypertension or diabetes.

Conclusions

Reduced kidney function is associated with increased SCD risk in the general population, especially with eGFRcys. eGFRcys could be added to prediction models and screening programmes for SCD prevention.

Prediction of sudden cardiac arrest in the general population: Review of traditional and emerging risk factors

Sudden cardiac death (SCD) is the most common and devastating outcome of sudden cardiac arrest (SCA), defined as an abrupt and unexpected cessation of cardiovascular function leading to circulatory collapse. The incidence of SCD is relatively infrequent for individuals in the general population, in the range of 0.03-0.10% per year. Yet, the absolute number of cases around the world is high due to the sheer size of the population at risk, making SCA/SCD a major global health issue. Based on conservative estimates, there are at least 2 million cases of SCA occurring worldwide on a yearly basis. As such, identification of risk factors associated with SCA in the general population is an important objective from a clinical and public health standpoint. This review will provide an in-depth discussion of established and emerging factors predictive of SCA/SCD in the general population beyond coronary artery disease and impaired left ventricular ejection fraction. Contemporary studies evaluating the association between age, sex, race, socioeconomic status and the emerging contribution of diabetes and obesity to SCD risk beyond their role as atherosclerotic risk factors will be reviewed. In addition, the role of biomarkers, particularly electrocardiographic ones, on SCA/SCD risk prediction in the general population will be discussed. Finally, the use of machine learning as a tool to facilitate SCA/SCD risk prediction will be examined.

Skin Sympathetic Nerve Activity and the Short-Term QT Interval Variability in Patients With Electrical Storm

Background: Skin sympathetic nerve activity (SKNA) and QT interval variability are known to be associated with ventricular arrhythmias. However, the relationship between the two remains unclear.

Objective: The aim was to test the hypothesis that SKNA bursts are associated with greater short-term variability of the QT interval (STVQT) in patients with electrical storm (ES) or coronary heart disease without arrhythmias (CHD) than in healthy volunteers (HV).

Methods: We simultaneously recorded the ECG and SKNA during sinus rhythm in patients with ES (N = 10) and CHD (N = 8) and during cold-water pressor test in HV (N = 12). The QT and QTc intervals were manually marked and calculated within the ECG. The STVQT was calculated and compared to episodes of SKNA burst and non-bursting activity.

Results: The SKNA burst threshold for ES and HV was 1.06 ± 1.07 and 1.88 ± 1.09 μV, respectively (p = 0.011). During SKNA baseline and burst, the QT/QTc intervals and STVQT for ES and CHD were significantly higher than those of the HV. In all subjects, SKNA bursts were associated with an increased STVQT (from 6.43 ± 2.99 to 9.40 ± 5.12 ms, p = 0.002 for ES; from 9.48 ± 4.40 to 12.8 ± 5.26 ms, p = 0.016 for CHD; and from 3.81 ± 0.73 to 4.49 ± 1.24 ms, p = 0.016 for HV). The magnitude of increased STVQT in ES (3.33 ± 3.06 ms) and CHD (3.34 ± 2.34 ms) was both higher than that of the HV (0.68 ± 0.84 ms, p = 0.047 and p = 0.020).

Conclusion: Compared to non-bursting activity, SKNA bursts were associated with a larger increase in the QTc interval and STVQT in patients with heart disease than in HV.

OUP accepted manuscript

More than 40 years after the first implantable cardioverter-defibrillator (ICD) implantation, sudden cardiac death (SCD) still accounts for more than five million deaths worldwide every year. Huge efforts in the field notwithstanding, it is now increasingly evident that the current strategy of long-term prevention based on left ventricular ejection fraction as the key selection criterion is actually of very limited impact, also because the largest absolute numbers of SCD are encountered in the general population not known to be at risk. It has been recently reemphasized that SCD is often not so sudden, with almost half of the victims experiencing typical warning symptoms preceding the event. Importantly, heeded and prompt medical attention can dramatically improve survival. Essentially, such timely action increases the chances of the SCD event being witnessed by emergency medical services and provides the opportunity for early intervention. In addition, newer technologies incorporating digital data acquisition, transfer between interconnected devices, and artificial intelligence, should allow dynamic, real-time monitoring of diverse parameters and therefore better identification of subjects at short-term SCD risk. Along with warning symptoms, these developments allow a new approach of near-term prevention based on the hours and minutes preceding SCD. In the present review, we challenge the current paradigm of mid- and long-term prevention using ICD in patients at the highest risk of SCD, and introduce a complementary concept applicable to the entire population that would aim to pre-empt SCD by timely detection and intervention within the minutes or hours prior to the event.

Use of Coronary CT Angiography as a Screening Tool for Coronary Artery Disease in Asymptomatic Healthy Individuals or Patients

심장 돌연사 환자들은 종종 흉통 또는 운동성 호흡곤란 등의 전조증상이 나타나지 않기 때문에 잠재적인 무증상 관상동맥 질환을 조기에 발견하는 것이 매우 중요하다. 관상동맥 전산화단층촬영 혈관조영술은 방사선 노출로 인한 위험성 때문에 무증상 환자에서 스크리닝 검사로 정당화되지 못했었지만 최근에 전산화단층촬영 기술의 비약적인 발전으로 방사선량을 1 mSv 미만으로 최소화함으로써 무증상 환자의 관상동맥 질환 선별 검사의 유용성에 대한 많은 연구가 진행되어 왔다. 그러나, 여전히 무증상 정상인 또는 환자의 관상동맥 질환 선별 검사에 대한 관상동맥 전산화단층촬영 혈관조영술의 유용성에 대해서는 다양한 의견들이 있다. 이 종설에서는 무증상 정상인 또는 환자들에게 관상동맥 질환 선별 검사로 관상동맥 칼슘 점수와 관상동맥 전산화단층촬영 혈관조영술 유용성에 대해서 다양한 문헌고찰을 통해서 알아보았다. 관상동맥 전산화단층촬영 혈관조영술상 무증상 정상인의 2.6%에서 70% 이상의 유의한 관상동맥 협착이 발견되었고, 선별 목적의 관상동맥 전산화단층촬영 혈관조영술이 무증상 건강한 사람의 미래의 심혈관 질환 발생을 예측할 수 있다. 그러나 현재 미국국립보건원에서 진행하고 있는 SCOT-HEART 2 연구가 끝나면 관상동맥 전산화단층촬영 혈관조영술이 무증상 성인의 심혈관 예방에 선별 검사로 적절한지 결정을 내릴 수 있을 것으로 생각된다.

Higher chances of survival to hospital admission after out-of-hospital cardiac arrest in patients with previously diagnosed heart disease

Aim

This study aimed to determine whether patients suffering from out-of-hospital cardiac arrest (OHCA) with a pre-OHCA diagnosis of heart disease have higher survival chances than patients without such a diagnosis and to explore possible underlying mechanisms.

Methods

A retrospective cohort study in 3760 OHCA patients from the Netherlands (2010–2016) was performed. Information from emergency medical services, treating hospitals, general practitioner, resuscitation ECGs and civil registry was used to assess medical histories and the presence of pre-OHCA diagnosis of heart disease. We used multivariable regression analysis to calculate associations with survival to hospital admission or discharge, immediate causes of OHCA (acute myocardial infarction (AMI) vs non-AMI) and initial recorded rhythm.

Results

Overall, 48.1% of OHCA patients had pre-OHCA heart disease. These patients had higher odds to survive to hospital admission than patients without pre-OHCA heart disease (OR 1.25 (95%CI 1.05 to 1.47)), despite being older and more often having cardiovascular risk factors and some non-cardiac comorbidities. These patients also had higher odds of shockable initial rhythm (SIR) (OR 1.60 (1. 36 to 1.89)) and a lower odds of AMI as immediate cause of OHCA (OR 0.33 (0.25 to 0.42)). Their chances of survival to hospital discharge were not significantly larger (OR 1.16 (0.95 to 1.42)).

Conclusion

Having pre-OHCA diagnosed heart disease is associated with better odds to survive to hospital admission, but not to hospital discharge. This is associated with higher odds of a SIR and in a subgroup with available diagnosis a lower proportion of AMI as immediate cause of OHCA.

Prevalence and associated risk factors of coronary artery disease in patients with a zero coronary calcium score

PURPOSE

A zero coronary calcium score (CCS) is not able to provide a definite exclusion for coronary artery disease (CAD). The goal of this study was to determine the prevalence and associated cardiovascular risk factors of CAD in patients with zero CCS.

METHODS

Six hundred thirteen patients with zero CCS referred to coronary calcium score analysis (CCSA) and coronary computed tomography angiography (CCTA) with suspicion of CAD were included. The descriptive, univariate, and multivariate analyses were used to determine the prevalence and predictors of CAD presence.

RESULTS

Among 613 patients, 17 patients (2.7%) have NCCP, and obstructive CAD was found in 3 patients (0.48%). Multivariate analysis revealed that male gender and older age (≥50 years) were significantly associated with the presence of noncalcified coronary plaques (NCCP) (p < 0.05). The receiver operating characteristic (ROC) curve analysis showed that the male gender and older age (≥50 years) model had 70.6% sensitivity and 84.2% specificity for predicting NCCP.

CONCLUSION

A non-negligible portion of patients with zero CCS had CAD. Male gender and older age (≥50 years) were independently associated with NCCP. Due to the high specificity value (84.2%) and negative predictive value (99.0%) of the male gender and older age (≥50 years) model, selective use of CCTA is recommended in <50 years old female patients to avoid unnecessary radiation exposure.

Application of two novel electrical restitution-based ECG markers of ventricular arrhythmia to patients with nonischemic cardiomyopathy

INTRODUCTION

Sudden cardiac death (SCD) risk assessment is limited, particularly in patients with nonischemic cardiomyopathies. This is the first application, in patients with cardiomyopathies, of two novel risk markers, regional restitution instability index (R2I2) and peak electrocardiogram restitution slope (PERS), which have been shown to be predictive of ventricular arrhythmias (VA) or death in ischemic heart disease patients.

METHODS

Blinded retrospective study of 50 patients: 33 dilated cardiomyopathy and 17 other; undergoing electrophysiological study (EPS) for SCD risk stratification, and 29 controls with structurally normal hearts undergoing EPS. R2I2 was calculated from an EPS using electrocardiogram surrogates for action potential duration and diastolic interval. Cut-offs for high and low R2I2/PERS were predefined.

RESULTS

R2I2 was significantly higher in study than control patients (0.99 ± 0.05 vs. 0.63 ± 0.04, p < .001). PERS showed a trend to higher values in the study group (1.18[0.63] vs. 1.09[0.54], p = .07). During median follow up of 5.6 years [interquartile range 1.9 years], nine study patients reached the endpoint of VA/death. Patients who experienced VA/death showed trends to higher mean R2I2 (1.14 ± 0.07 vs.0.95 ± 0.05, p = .12) and PERS (1.46[0.49] vs. 1.13[0.62], p = .22). A Cox proportional hazards model using grouped markers: R2I2 < 1.03 + PERS < 1.21/either R2I2 ≥ 1.03 or PERS ≥ 1.21/R2I2 ≥ 1.03 + PERS ≥ 1.21; significantly predicted VA/death (p = .02) with a hazard ratio per positive component of 3.2 (95% confidence interval 1.2-8.8).

CONCLUSION

R2I2≥ 1.03 + PERS ≥ 1.21 may predict VA/death in patients with cardiomyopathies. R2I2 ≥ 1.03 + PERS ≥ 1.21 have the potential to play an important role in SCD risk stratification in cardiomyopathies but their validity should be confirmed in a larger study.

Leading 20 drug-drug interactions, polypharmacy, and analysis of the nature of risk factors due to QT interval prolonging drug use and potentially inappropriate psychotropic use in elderly psychiatry outpatients

BACKGROUND

Psychotropic medications extend corrected QT (QTc) period in the electrocardiogram (ECG). Psychiatric patients exposed to ⩾1 psychotropic medication(s) represent a group with marked probability of drug-activated QTc-prolongation. Prolonged QTc interval in elderly patients (age > 60 years) is connected to greater risk of all-cause and coronary heart disease deaths. This study aimed at investigating pattern of utilization of QTc-interval protracting medications, QT-extending drug interactions, and prevalence of QTc-interval extending hazard factors in elderly patients.

METHODS

This was a cross-sectional, prospective study at the Psychiatry OPD at All India Institute of Medical Sciences (AIIMS), Rishikesh, Uttarakhand, India from 1 October 2017 to 30 August 2019 employing the pertinent prescriptions.

RESULTS

A total of 832 elderly patients (age 60 years or more) visiting the Psychiatry OPD during the aforementioned study duration were investigated. About 420 (50.5%) patients were males while 412 (49.5%) were females. Of the 832 patients, 588 (70.7%) were using interacting agents with capacity to produce TdP. Almost 1152 interacting torsadogenic medication pairs were unraveled. As per AzCERT/CredibleMeds Classification, 1016 (48.8%), 724 (34.8%), and 248 (12%) agents with potential to interact were identified with 'known', 'possible', and 'conditional risk of TdP', respectively. The common interacting medications belonged to antidepressant (288), proton pump inhibitor (364), antipsychotic (340), antinausea (184), antimicrobial (156), and H2 receptor antagonist (60) therapeutic categories. The all-inclusive frequency of potentially inappropriate psychotropic (PIP) agents administered was 62% (1343/2166) with Beers Criteria 2019, and 46% (997/2166) with STOPP Criteria 2015.

CONCLUSION

Many geriatric patients were administered drugs and drug combinations with heightened proclivity toward QT-interval prolongation. Furthermore, reliable evidence-based online drug knowledge resources, such as AzCERT/CredibleMeds Drug Lists, Medscape Drug Interactions Checker, Epocrates Online Interaction Check, and Drugs.com Drug Interactions Checker, can facilitate clinical professionals in selecting drugs for psychiatric patients. A wise choice of medications is imperative to preclude serious adverse sequelae. Therefore, we need to exigently embrace precautionary safety means, be vigilant, and forestall QT-extension and TdP in clinical environments.

Top 20 drug - drug interactions, polypharmacy and analysis of the nature of risk factors due to QT interval prolonging drug use in elderly psychiatry outpatients

INTRODUCTION AND OBJECTIVES

Psychotropic medications extend the corrected QT (QTc) period in the ECG. Psychiatric patients exposed to ≥ 1 psychotropic medication (s) represent a group with a marked probability of drug-activated QTc-prolongation. Prolonged QTc interval in elderly patients (age > 60 years) is connected to a greater risk of all-cause and coronary heart disease deaths. We investigated the pattern of utilization of QTc-interval prolonging medications, QT-extending interactions between drugs, and prevalence of QTc-interval prolonging risk factors in elderly patients.

METHODS

This was a cross-sectional, prospective study at the Psychiatry OPD at All India Institute of Medical Sciences (AIIMS), Rishikesh, Uttarakhand, India from October 1, 2017 to December 31, 2018 employing the pertinent prescriptions.

RESULTS

A total of 208 elderly patients (age 60 years or more) visiting the Psychiatry OPD during the aforementioned study period were investigated. 105 (50.5%) patients were males whereas 103 (49.5%) were females in our study. 147 out of 208 patients (70.7%) were using interacting agents with the capacity to produce TdP. 288 interacting torsadogenic medication pairs were unraveled. As per AzCERT/CredibleMeds Classification, 254 (48.8%), 181 (34.8%), and 62 (12%) interacting medications were identified with known, possible, and conditional risk of TdP, respectively. The common interacting medications belonged to antidepressant (144), proton pump inhibitor (91), antipsychotic (85), anti-nausea (46), antimicrobial (39), and H2 receptor antagonist (15) therapeutic categories.

CONCLUSIONS

Many geriatric patients were administered drugs and drug combinations with heightened proclivity towards QT-interval prolongation. Therefore, we need to exigently embrace precautionary safety interventions, to be vigilant, and forestall QT-prolongation and TdP in clinical settings. Online evidence-based drug information resources can aid clinicians in choosing drugs for psychiatric patients.

Association and Prediction of Subclinical Atherosclerosis by Nonalcoholic Fatty Liver Disease in Asymptomatic Patients

Background

The prevalence of nonalcoholic fatty liver disease (NAFLD) has been increasing in the general population. This study evaluated the association between NAFLD and significant coronary stenosis in asymptomatic adults and evaluated sex-based differences.

Methods

We performed a retrospective cross-sectional study in participants without previous cardiovascular diseases who visited the Seoul National University Hospital Health Promotion Center for a health checkup between January 1, 2010, and December 31, 2015. NAFLD was diagnosed on sonography, while coronary artery stenosis (CAS) was assessed on coronary computed tomography angiography (CCTA).

Results

We obtained 3,693 participants who met the inclusion criteria, and 3,449 of them had no significant stenosis. Among the participants with significant stenosis, the prevalence of NAFLD was 59.4% (145 patients). The prevalence of NAFLD was 47.26% in male participants, which was higher than that in female participants. The association between NAFLD and significant CAS persisted after adjusting for age, body mass index, glycated hemoglobin, and Framingham risk factors. The correlation between NAFLD and significant coronary stenosis appeared to be stronger in women than in men, but the absolute risk was higher in men than in women.

Conclusion

NAFLD was strongly associated with CAS. We should be alert about an increased cardiovascular risk in patients with NAFLD and more intensively provide primary prevention by performing tests to detect subclinical atherosclerosis.

Arrhythmic risk stratification in post-myocardial infarction patients with preserved ejection fraction: the PRESERVE EF study

Aims

Sudden cardiac death (SCD) annual incidence is 0.6–1% in post-myocardial infarction (MI) patients with left ventricular ejection fraction (LVEF)≥40%. No recommendations for implantable cardioverter-defibrillator (ICD) use exist in this population.

Methods and results

We introduced a combined non-invasive/invasive risk stratification approach in post-MI ischaemia-free patients, with LVEF ≥ 40%, in a multicentre, prospective, observational cohort study. Patients with at least one positive electrocardiographic non-invasive risk factor (NIRF): premature ventricular complexes, non-sustained ventricular tachycardia, late potentials, prolonged QTc, increased T-wave alternans, reduced heart rate variability, abnormal deceleration capacity with abnormal turbulence, were referred for programmed ventricular stimulation (PVS), with ICDs offered to those inducible. The primary endpoint was the occurrence of a major arrhythmic event (MAE), namely sustained ventricular tachycardia/fibrillation, appropriate ICD activation or SCD. We screened and included 575 consecutive patients (mean age 57 years, LVEF 50.8%). Of them, 204 (35.5%) had at least one positive NIRF. Forty-one of 152 patients undergoing PVS (27–7.1% of total sample) were inducible. Thirty-seven (90.2%) of them received an ICD. Mean follow-up was 32 months and no SCDs were observed, while 9 ICDs (1.57% of total screened population) were appropriately activated. None patient without NIRFs or with NIRFs but negative PVS met the primary endpoint. The algorithm yielded the following: sensitivity 100%, specificity 93.8%, positive predictive value 22%, and negative predictive value 100%.

Conclusion

The two-step approach of the PRESERVE EF study detects a subpopulation of post-MI patients with preserved LVEF at risk for MAEs that can be effectively addressed with an ICD.

Clinicaltrials.gov identifier

NCT02124018

Arrhythmic risk stratification in heart failure mid-range ejection fraction patients with a non-invasive guiding to programmed ventricular stimulation two-step approach

BACKGROUND

Although some post myocardial infarction (post-MI) and dilated cardiomyopathy (DCM) patients with mid-range ejection fraction heart failure (HFmrEF/40%-49%) face an increased risk for arrhythmic sudden cardiac death (SCD), current guidelines do not recommend an implantable cardiac defibrilator (ICD). We risk stratified hospitalized HFmrEF patients for SCD with a combined non-invasive risk factors (NIRFs) guiding to programmed ventricular stimulation (PVS) two-step approach.

METHODS

Forty-eight patients (male = 83%, age = 64 ± 14 years, LVEF = 45 ± 5%, CAD = 69%, DCM = 31%) underwent a NIRFs screening first-step with electrocardiogram (ECG), SAECG, Echocardiography and 24-hour ambulatory ECG (AECG). Thirty-two patients with presence of one of three NIRFs (SAECG ≥ 2 positive criteria for late potentials, ventricular premature beats ≥ 240/24 hours, and non-sustained ventricular tachycardia [VT] episode ≥ 1/24 hours) were further investigated with PVS. Patients were classified as either low risk (Group 1, n = 16, NIRFs-), moderate risk (Group 2, n = 18, NIRFs+/PVS-), and high risk (Group 3, n = 14, NIRFs+/PVS+). All in Group 3 received an ICD.

RESULTS

After 41 ± 18 months, 9 of 48 patients, experienced the major arrhythmic event (MAE) endpoint (clinical VT/fibrillation = 3, appropriate ICD activation = 6). The endpoint occurred more frequently in Group 3 (7/14, 50%) than in Groups 1 and 2 (2/34, 5.8%). Logistic regression model adjusted for PVS, age, and LVEF revealed that PVS was an independent MAE predictor (OR: 21.152, 95% CI: 2.618-170.887, P = .004). Kaplan-Meier curves diverged significantly (log rank, P < .001) while PVS negative predictive value was 94%.

CONCLUSIONS

In hospitalized HFmrEF post-MI and DCM patients, a NIRFs guiding to PVS two-step approach efficiently detected the subgroup at increased risk for MAE.

Proarrhythmic electrophysiological and structural remodeling in rheumatoid arthritis

Chronic inflammatory disorders, including rheumatoid arthritis (RA), are associated with a twofold increase in the incidence of sudden cardiac death (SCD) compared with the healthy population. Although this is partly explained by an increased prevalence of coronary artery disease, growing evidence suggests that ischemia alone cannot completely account for the increased risk. The present review explores the mechanisms of cardiac electrophysiological remodeling in response to chronic inflammation in RA. In particular, it focuses on the roles of nonischemic structural remodeling, altered cardiac ionic currents, and autonomic nervous system dysfunction in ventricular arrhythmogenesis and SCD. It also explores whether common genetic elements predispose to both RA and SCD. Finally, it evaluates the potential dual effects of disease-modifying therapy in both diminishing and promoting the risk of ventricular arrhythmias and SCD.

Autonomic dysfunction and sudden death in patients with Rett syndrome: a systematic review

BACKGROUND

Rett syndrome (RTT), a debilitating neuropsychiatric disorder that begins in early childhood, is characterized by impairments in the autonomic nervous system that can lead to sudden unexpected death. This study explores the mechanisms of autonomic dysfunction to identify potential risk factors for sudden death in patients with RTT.

METHODS

Following the Reporting Items for Systematic Review and Meta-Analyses (PRISMA) criteria, we undertook comprehensive systematic reviews using the PubMed, Scopus, Cochrane, PsycINFO, Embase and Web of Science databases.

RESULTS

We identified and critically appraised 39 articles for autonomic dysfunction and 5 for sudden death that satisfied the eligibility criteria. Following thematic analysis, we identified 7 themes: breathing irregularities, abnormal spontaneous brainstem activations, heart rate variability metrics, QTc changes, vagal imbalance, fluctuation in peptides and serotonergic neurotransmission. We grouped these 7 themes into 3 final themes: (A) brainstem modulation of breathing, (B) electrical instability of the cardiovascular system and (C) neurochemical changes contributing to autonomic decline. We described key evidence relating to each theme and identified important areas that could improve the clinical management of patients with RTT.

LIMITATIONS

The heterogeneity of the methods used to assess autonomic function increased the difficulty of making inferences from the different studies.

CONCLUSION

This study identified the important mediators of autonomic dysfunction and sudden death in patients with RTT. We proposed brainstem mechanisms and emphasized risk factors that increase brainstem vulnerability. We discussed clinical management to reduce sudden death and future directions for this vulnerable population.

MicroRNAs in cardiovascular disease

Cardiovascular disease (CVD) remains the predominant cause of human morbidity and mortality in developed countries. Currently, microRNAs have been investigated in many diseases as well-promising biomarkers for diagnosis, prognosis, and disease monitoring. Plenty studies have been designed so as to elucidate the properties of microRNAs in the classification and risk stratification of patients with CVD and also to evaluate their potentials in individualized management and guide treatment decisions. Therefore, in this review article, we aimed to present the most recent data concerning the role of microRNAs as potential novel biomarkers for cardiovascular disease.

Ischemia Enhances the Acute Stretch-Induced Increase in Calcium Spark Rate in Ventricular Myocytes

Introduction: In ventricular myocytes, spontaneous release of calcium (Ca²⁺) from the sarcoplasmic reticulum via ryanodine receptors (“Ca²⁺ sparks”) is acutely increased by stretch, due to a stretch-induced increase of reactive oxygen species (ROS). In acute regional ischemia there is stretch of ischemic tissue, along with an increase in Ca²⁺ spark rate and ROS production, each of which has been implicated in arrhythmogenesis. Yet, whether there is an impact of ischemia on the stretch-induced increase in Ca²⁺ sparks and ROS has not been investigated. We hypothesized that ischemia would enhance the increase of Ca²⁺ sparks and ROS that occurs with stretch.

Methods: Isolated ventricular myocytes from mice (male, C57BL/6J) were loaded with fluorescent dye to detect Ca²⁺ sparks (4.6 μM Fluo-4, 10 min) or ROS (1 μM DCF, 20 min), exposed to normal Tyrode (NT) or simulated ischemia (SI) solution (hyperkalemia [15 mM potassium], acidosis [6.5 pH], and metabolic inhibition [1 mM sodium cyanide, 20 mM 2-deoxyglucose]), and subjected to sustained stretch by the carbon fiber technique (~10% increase in sarcomere length, 15 s). Ca²⁺ spark rate and rate of ROS production were measured by confocal microscopy.

Results: Baseline Ca²⁺ spark rate was greater in SI (2.54 ± 0.11 sparks·s⁻¹·100 μm⁻²; n = 103 cells, N = 10 mice) than NT (0.29 ± 0.05 sparks·s⁻¹·100 μm⁻²; n = 33 cells, N = 9 mice; p < 0.0001). Stretch resulted in an acute increase in Ca²⁺ spark rate in both SI (3.03 ± 0.13 sparks·s⁻¹·100 μm⁻²; p < 0.0001) and NT (0.49 ± 0.07 sparks·s⁻¹·100 μm⁻²; p < 0.0001), with the increase in SI being greater than NT (+0.49 ± 0.04 vs. +0.20 ± 0.04 sparks·s⁻¹·100 μm⁻²; p < 0.0001). Baseline rate of ROS production was also greater in SI (1.01 ± 0.01 normalized slope; n = 11, N = 8 mice) than NT (0.98 ± 0.01 normalized slope; n = 12, N = 4 mice; p < 0.05), but there was an acute increase with stretch only in SI (+12.5 ± 2.6%; p < 0.001).

Conclusion: Ischemia enhances the stretch-induced increase of Ca²⁺ sparks in ventricular myocytes, with an associated enhancement of stretch-induced ROS production. This effect may be important for premature excitation and/or in the development of an arrhythmogenic substrate in acute regional ischemia.

Out-of-hospital cardiac arrest in the Pilsen Region in 2018

AIMS

To acquire epidemiological data on pre-hospital cardiac arrest incidents occurring in the Pilsen Region of the Czech Republic in 2018, and the results of subsequent cardiopulmonary resuscitation Methods. A prospective observational study of the survival rate of out-of-hospital cardiac arrest (OHCA) in patients undergoing CPR carried out by emergency medical service personnel. The observed time period was from January 1^st, 2018 until December 31^st, 2018. The data were acquired from patients' records in paper and electronic forms.

RESULTS

In the monitored period 707 patients with signs of cardiac arrest were recorded in the Pilsen Region with an incidence rate of 128.9 per 100,000 inhabitants. Emergency medical units performed CPR in 484 cases. The incidence rate of pre-hospital CPR was 88.2 cases per 100,000 inhabitants. Spontaneous blood circulation was temporarily or permanently restored in 276 patients (57.0%), 203 (41.9%) patients were transferred to a hospital, and there were 61 (12.6%) cases of survival with Cerebral Performance Category (CPC) score of 1 or 2. The first monitored rhythm was a shockable in 134 (27.7%) cases. In this sub-group ROSC was achieved in 94 (70.1%) cases and 58 (43.3%) of those were subsequently transferred to a hospital. A good CPC result was achieved in 41 (30.6%) patients of this sub group.

CONCLUSION

The study has provided valuable epidemiological data on OHCA and prehospital CPR in the area of the Pilsen Region in 2018. The collected data, compared to international results, show a higher survival rate with good neurological score in 12.6% of cases.

Combined spatiotemporal and frequency-dependent shear wave elastography enables detection of vulnerable carotid plaques as validated by MRI

Fatal cerebrovascular events are often caused by rupture of atherosclerotic plaques. However, rupture-prone plaques are often distinguished by their internal composition rather than degree of luminal narrowing, and conventional imaging techniques might thus fail to detect such culprit lesions. In this feasibility study, we investigate the potential of ultrasound shear wave elastography (SWE) to detect vulnerable carotid plaques, evaluating group velocity and frequency-dependent phase velocities as novel biomarkers for plaque vulnerability. In total, 27 carotid plaques from 20 patients were scanned by ultrasound SWE and magnetic resonance imaging (MRI). SWE output was quantified as group velocity and frequency-dependent phase velocities, respectively, with results correlated to intraplaque constituents identified by MRI. Overall, vulnerable lesions graded as American Heart Association (AHA) type VI showed significantly higher group and phase velocity compared to any other AHA type. A selection of correlations with intraplaque components could also be identified with group and phase velocity (lipid-rich necrotic core content, fibrous cap structure, intraplaque hemorrhage), complementing the clinical lesion classification. In conclusion, we demonstrate the ability to detect vulnerable carotid plaques using combined SWE, with group velocity and frequency-dependent phase velocity providing potentially complementary information on plaque characteristics. With such, the method represents a promising non-invasive approach for refined atherosclerotic risk prediction.

The Relationship Between Hematological Parameters and Mortality in Cardiovascular Patients With Postcardiac Arrest Syndrome

Background: Post-cardiac arrest syndrome is the insufficiency of cardiac and cerebral functions caused by ischemia after sudden cardiac arrest. We aimed to determine the hematological parameters associated with mortality in the intensive care follow-up of patients with post-cardiac arrest syndrome.

Methods: The hematological parameters of 285 cardiovascular patients who were admitted to the emergency department of Harran University Medical Faculty between 2013 and 2018 and followed up in the intensive care unit with post-cardiac arrest syndrome were examined. A total of 85 patients were included in the study. These parameters were recorded as the time of arrival to the emergency department (0 hour) and hematological parameters at the 24^th and 48^th hours of intensive care follow-up.

Results: In the mortality group, albumin (P:0.030), hemoglobin (Hg) (P: 0.049), and hematocrit (HCT) (P: 0.020) values ​​in the blood parameters, at the time of admission to the emergency department, were significantly lower than those in the survival group. Red blood cell distribution width (RDW) (P: 0.009) and urea (P <0.001) values ​​at the time of arrival were higher than the survival group. In the 24^th and 48^th hours, mean hemoglobin (MCHC) (P <0.05) values ​​were lower and RDW (P <0.05) values ​​were higher in the mortality group compared to the survival group.

Conclusions: In this retrospective validation, low albumin, Hg, HCT, MCHC, and high RDW and urea levels may increase mortality in cardiovascular patients who develop post-cardiac arrest syndrome within the first 48 hours. Correcting these values ​​early may reduce mortality.

A New Methodology Based on EMD and Nonlinear Measurements for Sudden Cardiac Death Detection

Heart diseases are among the most common death causes in the population. Particularly, sudden cardiac death (SCD) is the cause of 10% of the deaths around the world. For this reason, it is necessary to develop new methodologies that can predict this event in the earliest possible stage. This work presents a novel methodology to predict when a person can develop an SCD episode before it occurs. It is based on the adroit combination of the empirical mode decomposition, nonlinear measurements, such as the Higuchi fractal and permutation entropy, and a neural network. The obtained results show that the proposed methodology is capable of detecting an SCD episode 25 min before it appears with a 94% accuracy. The main benefits of the proposal are: (1) an improved detection time of 25% compared with previously published works, (2) moderate computational complexity since only two features are used, and (3) it uses the raw ECG without any preprocessing stage, unlike recent previous works.

Associations between coronary artery stenosis detected by coronary computed tomography angiography and the characteristics of health checkup examinees in the Republic of Korea

INTRODUCTION

This study was conducted on healthy adults without a diagnosis related to cardiovascular disease to investigate the associations between asymptomatic coronary artery stenosis and the characteristics of health checkup examinees.

METHODS

This study was performed on 601 people (320 males and 281 females), who underwent coronary computed tomography angiography (CCTA), among health checkup examinees from January 2, 2015 to December 31, 2016. Those with any prior history of cardiovascular diseases, underwent coronary artery bypass grafting or coronary artery stenting in the past, those with atrial fibrillation, those suspected of contrast agent side effects, and those whose creatinine levels deviated from the normal range were excluded.

RESULTS

The mean age was 58.7 ± 8.0 years. Coronary artery stenosis was detected in 173 people (28.8%), and the mean coronary artery stenosis rate was 25.8 ± 12.8%. Regression analysis showed that coronary artery stenosis was influenced significantly by age, gender, glycated hemoglobin (HbA1c), past smoking duration, current smoking duration, and number of glasses of alcohol consumed (p < 0.05). In terms of the relationship between the presence of coronary artery stenosis and lifestyle habits, amount of alcohol consumed per day (p = 0.03), and patients with a longer period of past (p < 0.001) and current smoking duration (p = 0.01) had a significant effect on coronary artery stenosis.

CONCLUSION

These results suggest that men aged 60 years or older, who have consumed large amounts of alcohol and cigarettes for a long time, require continuous management through tests such as a health checkup, because of the high probability of coronary artery stenosis, even in those without specific symptoms.

Socio-economic differences in incidence, bystander cardiopulmonary resuscitation and survival from out-of-hospital cardiac arrest: A systematic review

BACKGROUND

Individuals with a low socioeconomic status (SES) may have a greater mortality rate from out of hospital cardiac arrest (OHCA) than those with a high SES. We explored whether SES disparities in OHCA mortality manifest in the incidence of OHCA, the chance of receiving bystander cardiopulmonary resuscitation (CPR) or in the chance of surviving an OHCA. We also studied whether sex and age differences exist in such SES disparities.

METHODS

The Medline, Embase and Scopus databases were searched from 01-01-1993 until 31-01-2019. Studies utilising any study design or population were included. Studies were included if the exposure was SES of the OHCA victim or the OHCA location and the outcome was either OHCA incidence, CPR provision and/or survival rate after OHCA. Study selection and quality assessment were conducted by two reviewers independently. Descriptive data and measures of association were extracted, both in the total study population and in subgroups stratified by age and/or sex. This review was carried out following the PRISMA guidelines.

RESULTS

Overall 32 studies were included. Twelve studies reported on OHCA incidence, thirteen on bystander CPR provision and fourteen on survival. Some evidence for SES differences was found in each identified stage. In all the studies on incidence, SES was measured over the area of the OHCA victims' residence and was consistently associated with OHCA. In studies on bystander CPR, SES of the area in which the OHCA occurred was associated with bystander CPR, while evidence on individual SES was lacking. In studies on OHCA survival, SES of the victim measured at the individual level and SES of the area in which the OHCA occurred were associated, while SES of the victim, measured at the area of residence was not. Studies reporting age and sex differences in the SES trends were scarce.

CONCLUSION

SES disparities in OHCA mortality likely manifest in OHCA incidence, bystander CPR provision and survival rate after OHCA. However, there is a distinct lack of data on SES measured at the individual level and on differences within subgroups, e.g. by sex and age.

Frequency, characteristics and nature of risk factors associated with use of QT interval prolonging medications and related drug-drug interactions in a cohort of psychiatry patients

Quite a number of antipsychotic and antidepressant drugs are known to cause significant QT-prolongation. Psychiatric patients constitute a population at notable risk of drug-induced QT-prolongation. The aims were to explore frequency of use of QTc-interval prolonging agents and QT-prolonging drug-drug interactions, and prevalence of risk factors for QTc-interval prolongation in patients reporting to psychiatry out-patient department (OPD) in a tertiary care hospital in India. This prospective cross-sectional study was carried out in the psychiatry OPD at All India Institute of Medical Sciences (AIIMS), Rishikesh, Uttarakhand, India from October 1, 2017 to September 30, 2018 using the relevant prescriptions (i.e., the OPD case record forms and treatment sheets). For each patient, the entire medication list was analyzed for the possibility of interactions, with particular attention on the high-risk QT prolonging ones. Arizona Center for Education and Research on Therapeutics (AZCERT) QT drug lists were used to classify TdP risks of psychotropic and other medications. One thousand three hundred twenty-six (1326) patients attending the psychiatry OPD during the study period were scrutinized. Seven hundred fifty-one 751 patients (56.6%) were males whereas 575 (43.4%) were females in our study. Of the 1326 patients, 636 patients (47.9%) were identified as receiving interacting medications with the ability to induce torsades de pointe (TdP). Nine hundred seventeen (917) interacting medication pairs with torsadogenic risk were encountered. The most frequently interacting medications were from antipsychotic (794), antidepressant (519), antimicrobial (84), proton pump inhibitor (80), anticonvulsant (66), and anti-nausea (25) therapeutic categories. As per AZCERT classification (CredibleMeds TdP risk-stratification lists), 597 (36.8%), 443 (27.3%) and 432 (26.7%) of the interacting medications were associated with known, possible, and conditional risk of TdP, respectively. Concurrent prescriptions of QT-prolonging drugs is frequent in psychiatry OPD setting. Appropriate precautions should be instituted to obviate undesirable outcomes arising out of these interactions. This highlights the pressing need for clear protocols & strategies for implementation to motivate careproviders with clarity in the context of drug use guidelines for rational and safe prescribing in psychiatry.

Pulse Wave Velocity in Atherosclerosis

Early detection of subclinical atherosclerosis is important to reduce patients' cardiovascular risk. However, current diagnostic strategy focusing on traditional risk factors or using risk scoring is not satisfactory. Non-invasive imaging tools also have limitations such as cost, time, radiation hazard, renal toxicity, and requirement for specialized techniques or instruments. There is a close interaction between arterial stiffness and atherosclerosis. Increased luminal pressure and shear stress by arterial stiffening causes endothelial dysfunction, accelerates the formation of atheroma, and stimulates excessive collagen production and deposition in the arterial wall, leading to the progression of atherosclerosis. Pulse wave velocity (PWV), the most widely used measure of arterial stiffness, has emerged as a useful tool for the diagnosis and risk stratification of cardiovascular disease (CVD). The measurement of PWV is simple, non-invasive, and reproducible. There have been many clinical studies and meta-analyses showing the association between PWV and coronary/cerebral/carotid atherosclerosis. More importantly, longitudinal studies have shown that PWV is a significant risk factor for future CVD independent of well-known cardiovascular risk factors. The measurement of PWV may be a useful tool to select subjects at high risk of developing subclinical atherosclerosis or CVD especially in mass screening.

Pulse Wave Velocity in Atherosclerosis

Early detection of subclinical atherosclerosis is important to reduce patients' cardiovascular risk. However, current diagnostic strategy focusing on traditional risk factors or using risk scoring is not satisfactory. Non-invasive imaging tools also have limitations such as cost, time, radiation hazard, renal toxicity, and requirement for specialized techniques or instruments. There is a close interaction between arterial stiffness and atherosclerosis. Increased luminal pressure and shear stress by arterial stiffening causes endothelial dysfunction, accelerates the formation of atheroma, and stimulates excessive collagen production and deposition in the arterial wall, leading to the progression of atherosclerosis. Pulse wave velocity (PWV), the most widely used measure of arterial stiffness, has emerged as a useful tool for the diagnosis and risk stratification of cardiovascular disease (CVD). The measurement of PWV is simple, non-invasive, and reproducible. There have been many clinical studies and meta-analyses showing the association between PWV and coronary/cerebral/carotid atherosclerosis. More importantly, longitudinal studies have shown that PWV is a significant risk factor for future CVD independent of well-known cardiovascular risk factors. The measurement of PWV may be a useful tool to select subjects at high risk of developing subclinical atherosclerosis or CVD especially in mass screening.

The Relation of Emergency Duties to Cardiac Death Among US Firefighters

Sudden cardiac death accounted for 42% of all firefighter duty-related fatalities over the last decade. This retrospective study analyzed available medical examiner records for duty-related firefighter fatalities among male firefighters 18 to 65 years of age that occurred between 1999 and 2014 and reported the pathoanatomic substrate for cardiac-related fatalities. Odds of duty-related cardiac death during specific duties compared with fire station duties were calculated by pathoanatomic substrate. There were 285 cardiac fatalities. Of fatalities, 80% had evidence at autopsy of coronary heart disease (CHD) and increased heart size (cardiomegaly and/or left ventricular hypertrophy). CHD alone, cardiomegaly or left ventricular hypertrophy, and causes other than CHD or increased heart size were identified in 7.7%, 6.0%, and 6.7% of fatalities, respectively. The largest proportion of deaths occurred during fire suppression (33%), although only 1% of annual occupational time was estimated to be spent performing this duty. For deaths attributed to CHD and increased heart size, fire suppression, alarm response, and physical training were associated with approximately a 112-fold, eightfold, and sevenfold increased risk of cardiac death, respectively, compared with station duties. In conclusion, the majority of firefighters who suffered a duty-related cardiac death had CHD and increased heart size, which was associated with a markedly increased risk of death during fire suppression compared with station duties. Targeted occupational medical screening for CHD and increased heart size may reduce duty-related cardiac deaths among firefighters.

Pathoanatomic Findings Associated With Duty-Related Cardiac Death in US Firefighters: A Case-Control Study

Background Sudden cardiac death accounts for the greatest proportion of duty-related deaths among US firefighters. Increased understanding of the pathoanatomic causes of sudden cardiac death and the risk associated with underlying cardiac pathologies is needed to develop evidence-based screening recommendations. Methods and Results Using autopsy data for duty-related firefighter fatalities occurring between 1999 and 2014, this retrospective case-control study compared cardiac findings of male firefighters aged 18 to 65 years who died on duty of cardiac-related causes with those who died of noncardiac trauma-related causes. Data from 276 cardiac cases and 351 noncardiac trauma controls were analyzed. Among cardiac cases, the most prevalent (82%) underlying pathoanatomic substrate was comorbid coronary heart disease and cardiomegaly/left ventricular hypertrophy. Cardiac cases had a higher prevalence of cardiomegaly (heart weight >450 g), left ventricular hypertrophy (left ventricular wall thickness ≥1.2 cm), and severe coronary artery stenosis (≥75%) than trauma controls (all P<0.001). In multivariate analyses, heart weight >450 g, coronary artery stenosis ≥75%, and evidence of a prior myocardial infarction were strong independent predictors of cardiac death, with odds ratios of 6.1 (95% confidence interval, 3.6-10.4), 9.3 (95% confidence interval, 5.3-16.1), and 6.2 (95% confidence interval, 3.4-11.3), respectively. Conclusions The majority of cardiac fatalities had evidence of both coronary heart disease and increased heart mass, and each condition was independently associated with a markedly elevated risk of cardiac death. Targeted screening for coronary heart disease, increased heart mass, and evidence of prior myocardial infarction should be considered to reduce duty-related cardiac deaths among firefighters.

LifeMap: towards the development of a new technology in sudden cardiac death risk stratification for clinical use

Sudden cardiac death (SCD) is a major cause of mortality presenting a significant unmet clinical need. Patients at risk of SCD are implanted with implantable cardioverter-defibrillators (ICDs) according to international guidelines based on clinical trial evidence. Implantable cardioverter-defibrillators are not inexpensive and not without problem in terms of inappropriate shocks and infection risk. Also, only a minority of patients implanted with the ICD ever use the device during its battery lifetime highlighting the fact that methods used for SCD risk stratification are inadequate. Better ways of predicting who is at risk of SCD are needed. In addition, there is no effective prevention due to the lack of understanding of the electrical mechanisms underlying SCD. Our group has been investigating the electrophysiological basis of ventricular fibrillation and have successfully applied our preclinical findings to translational studies in patients with ischaemic cardiomyopathy. We have developed two ECG markers which have been shown to be strong predictors of ventricular arrhythmias and SCD. Ongoing clinical studies are being carried out including a multicentre UK study to consolidate the evidence base. They are being incorporated into the technology, LifeMap, with the aim to develop a successful clinical tool for the assessment of SCD risk. We hereby present the scientific data leading to the technology and the development to date. The information provided here was presented at the European Heart Rhythm Association (EHRA) Europace/Cardiostim conference at which LifeMap won the EHRA Inventors Award 2016.

Is cardiovascular risk a concern when prescribing azithromycin?

The FDA has updated azithromycin package labeling to include the risk of prolonged cardiac repolarization and QT prolongation, which increase the possibility of cardiac dysrhythmias and torsades de pointes, especially in older adults. The update was initiated by a study that found an increased risk of death in patients taking azithromycin compared with those taking amoxicillin. However, cardiovascular results of other azithromycin studies have demonstrated discordant results, and more research is needed. In the meantime, providers should recognize that azithromycin has a role in the management of bacterial infections and should prescribe the antibiotic when warranted.

Continuous ST-Monitoring Function of Implantable Cardioverter Defibrillator Detects Silent Ischemia in Patients With Coronary Artery Disease

Background

Newer implantable cardioverter defibrillators can monitor intracardiac ECGs , but their ability to detect ischemia is unclear. This study investigated the usefulness of implantable cardioverter defibrillators with an ST‐monitoring function in coronary artery disease patients.

Methods and Results

We conducted a prospective study of implantable cardioverter defibrillator patients with the ST‐monitoring function. One hundred seventy‐three patients who received implantable cardioverter defibrillators for primary or secondary prevention of sudden cardiac death. All patients underwent medical examinations at least every 6 months, with standard 12‐lead ECGs and device checks that included analysis of the ST‐monitoring function. Myocardial perfusion imaging or coronary angiography was performed during the follow‐up. The mean follow‐up duration was 23.3±7.7 months. Significant ST changes occurred in 15 patients (8.7%), of whom 14 were asymptomatic. The incidence of angina pectoris was significantly higher in the ST change (+) group than that in the ST change (−) group (28.6% versus 7.2%, P=0.03). In the patients who underwent myocardial perfusion imaging, the sensitivity, specificity, and negative predictive value of the ST‐monitoring feature to detect ischemia were 75.0%, 72.5%, and 93.5%, respectively. The sensitivity, specificity, and negative predictive value of the ST‐monitoring feature to predict residual stenosis evaluated using coronary angiography were 76.9%, 83.5%, and 97.5%, respectively. The percentage of patients with a septal right ventricular lead was significantly lower in the ST change (+) group than in the ST change (−) group (13.5% versus 33.5%, P=0.01).

Conclusions

If intracardiac ECGs ST changes are detected, it is necessary to use additional modalities even in asymptomatic patients.

Clinical Trial Registration

URL: http://upload.umin.ac.jp. Unique identifier: UMIN000011824.