The significance of left ventricular ejection time in heart failure with reduced ejection fraction

Long-term myocardial effects of noninvasive ventilation in patients with obesity hypoventilation syndrome

INTRODUCTION

Chronic effects of noninvasive ventilation on myocardial function in patients with obesity hypoventilation syndrome (OHS) are scarcely understood. The aim of the present study was to evaluate the long-term effects of volume-targeted bilevel positive airway pressure ventilation (BiPAP) on cardiac parameters and myocardial biomarkers in patients with OHS.

METHODS

Clinically stable patients with OHS referred to the tertiary center for the initiation of long-term BiPAP therapy were consecutively enrolled. At baseline, all participants underwent overnight cardiorespiratory polygraphy. BiPAP therapy using volume-targeted spontaneous/timed mode delivered via an oro-nasal mask was initiated. Beat-to-beat noninvasive monitoring by impedance cardiography was used to assess heart function at baseline and after 3 and 12 months of BiPAP use. Serum troponin 1, N-Terminal Pro-B-Type Natriuretic Peptide (NT-ProBNP), tumor necrosis factor-alpha (TNF-α), and interleukin-6 (IL-6) were monitored.

RESULTS

Thirteen patients (10 men; mean age, 55.8 ± 9.8 years; mean body mass index of 47.8 ± 5.9 kg/m2) were recruited. From baseline to 3, and to 12 months of BiPAP use, left ventricular stroke volume (SV), ejection time (LVET), and ejection time index significantly increased (P = 0.030; P < 0.001; P = 0.003, respectively), while heart rate and systolic time ratio significantly decreased (P = 0.004; P = 0.034, respectively). Reductions in serum NT-proBNP, IL-6 and TNF-α were observed (P = 0.045; P = 0.018; P = 0.003, respectively). No significant changes in serum troponin were detected throughout the study.

CONCLUSIONS

The present findings of increased SV, in association with lengthening of LVET, reductions of NT-proBNP and reductions in circulatory inflammatory markers in patients with stable OHS and chronic moderate-to-severe daytime hypercapnia treated with BiPAP over 1 year support the role of this therapeutic mode in such patients.

The double barrel Impella exchange: A reliable method for uninterrupted mechanical circulatory support

Classic Impella exchange interrupts flow when the old device is pulled into the aorta before advancing the new device across the aortic valve, threatening circulatory collapse and loss of left ventricular access. In "double barrel," uninterrupted Impella exchange, the new device is placed into the ventricle alongside the old, where flow is first transitioned completely. Of 31 consecutive patients undergoing this procedure, none experienced intraoperative cardiac arrest, and 96.8% (30/31) had no new aortic insufficiency. One vascular complication ensued following known preoperative iliac injury. One patient suffered nonembolic stroke; another had subarachnoid hemorrhage. Fifty-five percent (17/31) of patients survived, with 22.6% (7/31) recovering, 25.8% (8/31) undergoing transplant, and 6.5% (2/31) transitioning to durable left ventricular assist device. Impella-only survival (83.3%, 10/12) was significantly higher than Impella-extracorporeal membrane oxygenation survival (36.8%, 7/19; (operating room) OR 14.46, 95% ((confidence interval) CI 1.74-119.93, p = 0.01). We conclude the "double barrel" technique is reliable in device-dependent cardiogenic shock patients, offering significant advantages and minimal risk.

Methods to Utilize Pulse Wave Velocity to Measure Alterations in Cerebral and Cardiovascular Parameters

Alzheimer's Disease (AD) is a global health issue, affecting over 6 million in the United States, with that number expected to increase as the aging population grows. As a neurodegenerative disorder that affects memory and cognitive functions, it is well established that AD is associated with cardiovascular risk factors beyond only cerebral decline. However, the study of cerebrovascular techniques for AD is still evolving. Here, we provide reproducible methods to measure impedance-based pulse wave velocity (PWV), a marker of arterial stiffness, in the systemic vascular (aortic PWV) and in the cerebral vascular (cerebral PWV) systems. Using aortic impedance and this relatively novel technique of cerebral impedance to comprehensively describe the systemic vascular and the cerebral vascular systems, we examined the sex-dependent differences in 5x transgenic mice (5XFAD) with AD under normal and high-fat diet, and in wild-type mice under a normal diet. Additionally, we validated our method for measuring cerebrovascular impedance in a model of induced stress in 5XFAD. Together, our results show that sex and diet differences in wildtype and 5XFAD mice account for very minimal differences in cerebral impedance. Interestingly, 5XFAD, and not wildtype, male mice on a chow diet show higher cerebral impedance, suggesting pathological differences. Opposingly, when we subjected 5XFAD mice to stress, we found that females showed elevated cerebral impedance. Using this validated method of measuring impedance-based aortic and cerebral PWV, future research may explore the effects of modifying factors including age, chronic diet, and acute stress, which may mediate cardiovascular risk in AD.

Loss of developmentally derived Irf8+ macrophages promotes hyperinnervation and arrhythmia in the adult zebrafish heart

Recent developments in cardiac macrophage biology have broadened our understanding of the critical functions of macrophages in the heart. As a result, there is further interest in understanding the independent contributions of distinct subsets of macrophage to cardiac development and function. Here, we demonstrate that genetic loss of interferon regulatory factor 8 (Irf8)-positive embryonic-derived macrophages significantly disrupts cardiac conduction, chamber function, and innervation in adult zebrafish. At 4 months post-fertilization (mpf), homozygous irf8st96/st96 mutants have significantly shortened atrial action potential duration and significant differential expression of genes involved in cardiac contraction. Functional in vivo assessments via electro- and echocardiograms at 12 mpf reveal that irf8 mutants are arrhythmogenic and exhibit diastolic dysfunction and ventricular stiffening. To identify the molecular drivers of the functional disturbances in irf8 null zebrafish, we perform single cell RNA sequencing and immunohistochemistry, which reveal increased leukocyte infiltration, epicardial activation, mesenchymal gene expression, and fibrosis. Irf8 null hearts are also hyperinnervated and have aberrant axonal patterning, a phenotype not previously assessed in the context of cardiac macrophage loss. Gene ontology analysis supports a novel role for activated epicardial-derived cells (EPDCs) in promoting neurogenesis and neuronal remodeling in vivo. Together, these data uncover significant cardiac abnormalities following embryonic macrophage loss and expand our knowledge of critical macrophage functions in heart physiology and governing homeostatic heart health.

Is the Corrected Carotid Flow Time a Clinically Acceptable Surrogate Hemodynamic Parameter for the Left Ventricular Ejection Time?

OBJECTIVE

The corrected left ventricular ejection time (cLVET) comprises the phase from aortic valve opening to aortic valve closure corrected for heart rate. As a surrogate measure for cLVET, the corrected carotid flow time (ccFT) has been proposed in previous research. The aim of this study was to assess the clinical agreement between cLVET and ccFT in a dynamic clinical setting.

METHODS

Twenty-five patients with severe aortic valve stenosis (AS) were selected for transcatheter aortic valve replacement (TAVR). The cLVET and ccFT were derived from the left ventricular outflow tract (LVOT) and the common carotid artery (CCA), respectively, using pulsed wave Doppler ultrasound. Bazett's (B) and Wodey's (W) equations were used to calculate cLVET and ccFT. Measurements were performed directly before (T1) and after (T2) TAVR. Correlation, Bland-Altman and concordance analyses were performed.

RESULTS

Corrected LVET decreased from T1 to T2 (p < 0.001), with relative reductions of 11% (B) and 9% (W). Corrected carotid flow time decreased (p < 0.001), with relative reductions of 12% (B) and 10% (W). The correlation between cLVET and ccFT was strong for B (ρ = 0.74, p < 0.001) and W (ρ = 0.81, p < 0.001). The bias was -39 ms (B) and -37 ms (W), and the upper and lower levels of agreement were 19 and -98 ms (B) and 5 and -78 ms (W), respectively. Trending ability between cLVET and ccFT was good (concordance 96%) for both B and W.

CONCLUSION

In TAVR patients, the clinical agreement between cLVET and ccFT was acceptable, indicating that ccFT could serve as a surrogate measure for cLVET.

Central Artery Hemodynamics in Angiotensin II-Induced Hypertension and Effects of Anesthesia

Systemic hypertension is a strong risk factor for cardiovascular, neurovascular, and renovascular diseases. Central artery stiffness is both an initiator and indicator of hypertension, thus revealing a critical relationship between the wall mechanics and hemodynamics. Mice have emerged as a critical animal model for studying effects of hypertension and much has been learned. Regardless of the specific mouse model, data on changes in cardiac function and hemodynamics are necessarily measured under anesthesia. Here, we present a new experimental-computational workflow to estimate awake cardiovascular conditions from anesthetized data, which was then used to quantify effects of chronic angiotensin II-induced hypertension relative to normotension in wild-type mice. We found that isoflurane anesthesia had a greater impact on depressing hemodynamics in angiotensin II-infused mice than in controls, which led to unexpected results when comparing anesthetized results between the two groups of mice. Through comparison of the awake simulations, however, in vivo relevant effects of angiotensin II-infusion on global and regional vascular structure, properties, and hemodynamics were found to be qualitatively consistent with expectations. Specifically, we found an increased in vivo vascular stiffness in the descending thoracic aorta and suprarenal abdominal aorta, leading to increases in pulse pressure in the distal aorta. These insights allow characterization of the impact of regionally varying vascular remodeling on hemodynamics and mouse-to-mouse variations due to induced hypertension.

Artificial Intelligence Applied to Electrical and Non-Invasive Hemodynamic Markers in Elderly Decompensated Chronic Heart Failure Patients

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.

Update on the Use of Pulse Wave Velocity to Measure Age-Related Vascular Changes

PURPOSE OF REVIEW

Pulse wave velocity (PWV) is an important and well-established measure of arterial stiffness that is strongly associated with aging. Age-related alterations in the elastic properties and integrity of arterial walls can lead to cardiovascular disease. PWV measurements play an important role in the early detection of these changes, as well as other cardiovascular disease risk factors, such as hypertension. This review provides a comprehensive summary of the current knowledge of the effects of aging on arterial stiffness, as measured by PWV.

RECENT FINDINGS

This review highlights recent findings showing the applicability of PWV analysis for investigating heart failure, hypertension, and other cardiovascular diseases, as well as cerebrovascular diseases and Alzheimer's disease. It also discusses the clinical implications of utilizing PWV to monitor treatment outcomes, various challenges in implementing PWV assessment in clinical practice, and the development of new technologies, including machine learning and artificial intelligence, which may improve the usefulness of PWV measurements in the future. Measuring arterial stiffness through PWV remains an important technique to study aging, especially as the technology continues to evolve. There is a clear need to leverage PWV to identify interventions that mitigate age-related increases in PWV, potentially improving CVD outcomes and promoting healthy vascular aging.

Presystolic wave as a predictor of interatrial block in patients with supraventricular tachycardia

The identification of interatrial block (IAB) through electrocardiography (ECG) has been correlated with an elevated likelihood of developing atrial fibrillation (AF) and stroke. IAB is diagnosed by evaluating P-wave prolongation on a surface ECG. The presystolic wave (PSW) is an echocardiographic marker determined by pulse-wave examination of the aortic root during late diastole. As IAB and PSW share similar pathophysiological mechanisms, we speculated that PSW, as a component of the P wave, might be useful in predicting IAB. In the present study, we aimed to determine the relationship between PSW and IAB. Patients with pre-diagnosis of supraventricular tachycardia (SVT) on electrocardiography or rhythm Holter monitoring between January 2021 and December 2022 were included in the study. Surface 12-lead ECG and transthoracic echocardiography (TTE) were performed for the diagnosis of IAB and PSW. Patients were divided into two groups based on the presence of IAB, and PSW was compared between the groups. In total, 104 patients were enrolled in this study. IAB was diagnosed in 16 patients (15.3%) and PSW was detected in 33 patients (31.7%). The PSW was higher in the IAB ( +) group than in the IAB ( -) group (10 patients (71.4%) vs. 23 patients (32.4%), p = 0.008). PSW may be a useful tool for predicting IAB in patients with SVT. Further studies are needed to determine the clinical utility of PSW in the diagnosis and management of IAB.

Exploring the Connection Between Relaxed Myosin States and the Anrep Effect

The Anrep effect is an adaptive response that increases left ventricular contractility following an acute rise in afterload. Although the mechanistic origin remains undefined, recent findings suggest a two-phase activation of resting myosin for contraction, involving strain-sensitive and posttranslational phases. We propose that this mobilization represents a transition among the relaxed states of myosin-specifically, from the super-relaxed (SRX) to the disordered-relaxed (DRX)-with DRX myosin ready to participate in force generation. This hypothesis offers a unified explanation that connects myosin's SRX-DRX equilibrium and the Anrep effect as parts of a singular phenomenon. We underscore the significance of this equilibrium in modulating contractility, primarily studied in the context of hypertrophic cardiomyopathy, the most common inherited cardiomyopathy associated with diastolic dysfunction, hypercontractility, and left ventricular hypertrophy. As we posit that the cellular basis of the Anrep effect relies on a two-phased transition of myosin from the SRX to the contraction-ready DRX configuration, any dysregulation in this equilibrium may result in the pathological manifestation of the Anrep phenomenon. For instance, in hypertrophic cardiomyopathy, hypercontractility is linked to a considerable shift of myosin to the DRX state, implying a persistent activation of the Anrep effect. These valuable insights call for additional research to uncover a clinical Anrep fingerprint in pathological states. Here, we demonstrate through noninvasive echocardiographic pressure-volume measurements that this fingerprint is evident in 12 patients with hypertrophic obstructive cardiomyopathy before septal myocardial ablation. This unique signature is characterized by enhanced contractility, indicated by a leftward shift and steepening of the end-systolic pressure-volume relationship, and a prolonged systolic ejection time adjusted for heart rate, which reverses post-procedure. The clinical application of this concept has potential implications beyond hypertrophic cardiomyopathy, extending to other genetic cardiomyopathies and even noncongenital heart diseases with complex etiologies across a broad spectrum of left ventricular ejection fractions.

Assessment of left ventricular ejection fraction in artificial intelligence based on left ventricular opacification

Background

Left ventricular opacification (LVO) improves the accuracy of left ventricular ejection fraction (LVEF) by enhancing the visualization of the endocardium. Manual delineation of the endocardium by sonographers has observer variability. Artificial intelligence (AI) has the potential to improve the reproducibility of LVO to assess LVEF.

Objectives

The aim was to develop an AI model and evaluate the feasibility and reproducibility of LVO in the assessment of LVEF.

Methods

This retrospective study included 1305 echocardiography of 797 patients who had LVO at the Department of Ultrasound Medicine, Union Hospital, Huazhong University of Science and Technology from 2013 to 2021. The AI model was developed by 5-fold cross validation. The validation datasets included 50 patients prospectively collected in our center and 42 patients retrospectively collected in the external institution. To evaluate the differences between LV function determined by AI and sonographers, the median absolute error (MAE), spearman correlation coefficient, and intraclass correlation coefficient (ICC) were calculated.

Results

In LVO, the MAE of LVEF between AI and manual measurements was 2.6% in the development cohort, 2.5% in the internal validation cohort, and 2.7% in the external validation cohort. Compared with two-dimensional echocardiography (2DE), the left ventricular (LV) volumes and LVEF of LVO measured by AI correlated significantly with manual measurements. AI model provided excellent reliability for the LV parameters of LVO (ICC > 0.95).

Conclusions

AI-assisted LVO enables more accurate identification of the LV endocardium and reduces observer variability, providing a more reliable way for assessing LV function.

Cardiac Radiofrequency Ablation Exacerbates Myocardial Injury through Pro-Inflammatory Response and Pro-Oxidative Stress in Elderly Patients with Persistent Atrial Fibrillation

BACKGROUND

There is a need to assess myocardial damage after radiofrequency ablation of the pulmonary veins (PV) for persistent atrial fibrillation (PAF) in elderly patients.

OBJECTIVE

To evaluate oxidative stress, inflammatory response and myocardial damage in elderly patients with PAF after radiofrequency ablation of the PV.

METHODS

High-sensitivity troponin T (hsTnT), malondialdehyde-modified low-density lipoprotein (MDA-LDL), acrolein (ACR), lipid hydroperoxide (LHP), toll-like receptor 4 (TLR4), soluble growth stimulation expressed gene 2 (sST2), angiotensin II (Ang II) and myocardial blood flow (MBF) were determined before ablation and at 1, 3 and 5 months after radiofrequency ablation.

RESULTS

The levels of hsTnT, MDA-LDL, ACR, LHP, TLR4, sST2 and Ang II were increased 3 months after ablations compared with before ablation and 1 month after ablation, respectively (P<0.001); they were further increased at 5 months after ablation compared with the 1- and 3-month groups, respectively (P<0.001). MBF was decreased in the 3 months group after ablations compared with before ablation and 1-month after ablation, respectively (P<0.001), and was further decreased in 5-months after ablations compared with 1-month and 3-month groups, respectively (P<0.001). Patients with epicardial monopolar radiofrequency ablation had higher levels of hsTnT, MDA-LDL, ACR, LHP, TLR4, sST2, Ang II and lower MBF than patients with endocardial monopolar and bipolar radiofrequency ablations, respectively (P<0.001).

CONCLUSION

Monopolar radiofrequency ablation method could result in more myocardial injury than bipolar radiofrequency ablation. Oxidative stress and inflammatory response may be involved in cardiac radiofrequency ablation-induced myocardial injury, resulting in myocardial ischemia in elderly patients with PAF.

Cardiovascular effects of oxytocin and carbetocin at cesarean section. A prospective double-blind randomized study using noninvasive pulse wave analysis

BACKGROUND

Oxytocin is routinely administered after delivery for prophylaxis and treatment of postpartum hemorrhage, but it is associated with considerable cardiovascular side-effects. Carbetocin, a synthetic oxytocin analogue, has a myometrial contraction effect of 60 min when given IV, compared with 16 min for oxytocin.

OBJECTIVE

To investigate whether there are differences in cardiovascular effects between oxytocin and carbetocin up to 1 h after treatment.

METHODS

Sixty-one healthy pregnant women undergoing elective cesarean section in spinal anesthesia were randomized to receive an IV bolus of either five units (8.3 µg) of oxytocin or 100 µg of carbetocin after delivery of the baby. Heart rate (HR), mean arterial blood pressure, ECG ST index, oxygen saturation (SaO₂), and photoplethysmographic digital pulse wave analysis variables were recorded before and at 1, 5, 20, and 60 min after drug administration. Vasopressor use, uterine tonus, total bleeding, and need for additional uterotonics were also assessed. Repeated measurement ANOVA was used for statistical analyses.

RESULTS

The drugs had equal vasodilatory and hypotensive effects. Oxytocin, but not carbetocin, caused a decrease in HR at 1 min and a sustained decrease in cardiac left ventricular ejection time. Aggregate vasopressor use was higher in the carbetocin group. Neither drug caused any change in ST index, SaO₂, or subjective cardiac symptoms. Uterine tonus, need for additional uterotonics, or total bleeding did not differ significantly between the groups.

CONCLUSION

Single doses of oxytocin and carbetocin had similar dilatory effects on vascular tonus, where the difference in aggregate vasopressor use can be attributed to a more persistent hypotensive effect of carbetocin. A transient negative chronotropic and sustained negative inotropic effect occurred after oxytocin. Neither drug showed any alarmingly adverse effects. Differences in drug effects may be attributed to differences in oxytocin and vasopressin receptor signaling pathways.

Determination using impedance cardiograph of the chronic effects of different doses of radiotherapy on the cardiovascular system of rats

AIM

Cardiac damage caused by radiation in the long term varies according to the radiation dose received by the heart. In this study, it was aimed to evaluate the damage caused by different radiation doses in the heart, together with hemodynamic parameters, immunhistochemistry, and histopathological analyzes for long term.

METHOD AND MATERIALS

The animals were divided into four groups: The rats in control group (Group 1) were not irradiated; the rats in group 2 were irradiated with 5 Gy; the rats in group 3 were irradiated with 10 Gy and the rats in group 4 were irradiated with 20 Gy. Hemodynamic parameters and indices were determined from the impedance cardiography (ICG) recording in the whole groups before they were irradiated with RT and 180 days after RT. And then, interleukin-1β, interleukin-10, TNF-α, apopthosis were determined in all groups. In addition, histological changes of heart and aorta were evaluated.

RESULTS

Histopathologic, cytokine and hemodynamic findings supported that cardiac damage increased with increasing radiation dose.

CONCLUSION

it is important in terms of being an alternative and supportive method to other methods to be able to detect heart diseases caused by RT with the ICG method.

Heart rate-corrected systolic ejection time: population-based reference values and differential prognostic utility in acute heart failure

Aims

Systolic ejection time (SET) is discussed as a treatment target in patients with heart failure (HF) and a reduced left ventricular (LV) ejection fraction (EF). We derived reference values for SET correcting for its dependence on heart rate (SETc), and explored its prognostic utility in patients admitted with decompensated HF.

Methods and results

SETc was derived in 4836 participants of the population-based STAAB study (mean age 55 ± 12 years, 52% women). There, mean SETc was 328 ± 18 ms, increased with age (+4.7 ms per decade), was shorter in men than women (-14.9 ms), and correlated with arterial elastance (r = 0.30; all P < 0.001). In 134 patients hospitalized with acute HF, SETc at admission was shorter when compared with the general population and differed between patients with HF with reduced EF (HFrEF; LVEF ≤40%; 269 ± 35 ms), HF with mildly reduced EF (HFmrEF; LVEF 41-49%; 294 ± 27 ms), and HF with preserved EF (HFpEF; LVEF ≥50%; 317 ± 35 ms; P < 0.001). In proportional hazard regression, an in-hospital increase in SETc was associated with an age- and sex-adjusted hazard ratio of 0.38 (95% confidence interval 0.18-0.79) in patients with HFrEF, but a hazard ratio of 2.39 (95% confidence interval 1.24-4.64) in patients with HFpEF.

Conclusion

In the general population, SETc increased with age and an elevated afterload. SETc was mildly reduced in patients hospitalized with HFpEF, but markedly reduced in patients with HFrEF. In-hospital prolongation of SETc predicted a favourable outcome in HFrEF, but an adverse outcome in HFpEF. Our results support the concept of a U-shaped relationship between cardiac systolic function and risk, providing a rationale for a more individualized treatment approach in patients with HF.

Age- and sex-based normal reference ranges of the cardiac time intervals: the Copenhagen City Heart Study

BACKGROUND

Color tissue Doppler imaging (TDI) M-mode can be used to measure the cardiac time intervals including the isovolumic contraction time (IVCT), the left ventricular ejection time (LVET), the isovolumic relaxation time (IVRT), and the combination of all the cardiac time intervals in the myocardial performance index (MPI) defined as [(IVCT + IVRT)/LVET]. The aim of this study was to establish normal age- and sex-based reference ranges for the cardiac time intervals.

METHODS AND RESULTS

A total of 1969 participants free of cardiovascular diseases and risk factors from the general population with limited age range underwent an echocardiographic examination including TDI. The median age was 46 years (25th-75th percentile: 33-58 years), and 61.5% were females. In the entire study population, the IVCT was observed to be 40 ± 10 ms [95% prediction interval (PI) 20-59 ms], the LVET 292 ± 23 ms (95% PI 248-336 ms), the IVRT 96 ± 19 ms (95% PI 59-134 ms) and MPI 0.47 ± 0.09 (95% PI 0.29-0.65). All the cardiac time intervals differed significantly between females and males. With increasing age, the IVCT increased in females, but not in males. The LVET did not change with age in both sexes, while the IVRT increased in both sexes with increasing age. Furthermore, we developed regression equations relating the heart rate to the cardiac time intervals and age- and sex-based normal reference ranges corrected for heart rate.

CONCLUSION

In this study, we established normal age- and sex-based reference ranges for the cardiac time intervals. These normal reference ranges differed significantly with sex.

Changes in cardiac time intervals over a decade and the risk of incident heart failure: The Copenhagen City heart study

BACKGROUND

The cardiac time intervals include the isovolumic contraction time (IVCT), the left ventricular ejection time (LVET), the isovolumic relaxation time (IVRT) and the combination of all the cardiac time intervals in the myocardial performance index (MPI) (defined as [(IVCT+IVRT)/LVET)]. Whether the cardiac time intervals change over time and which clinical factors that accelerate these changes is not well-established. Additionally, whether these changes are associated with subsequent heart failure (HF), remains unknown.

METHODS

We investigated participants from the general population (n = 1064) who had an echocardiographic examination including color tissue Doppler imaging performed in both the 4th and 5th Copenhagen City Heart Study. The examinations were performed 10.5 years apart.

RESULTS

The IVCT, LVET, IVRT and MPI increased significantly over time. None of the investigated clinical factors were associated with increase in IVCT. Systolic blood pressure (standardized β= - 0.09) and male sex (standardized β= - 0.08) were associated with an accelerated decrease in LVET. Age (standardized β=0.26), male sex (standardized β=0.06), diastolic blood pressure (standardized β=0.08), and smoking (standardized β=0.08) were associated with an increase in IVRT, while HbA1c (standardized β= - 0.06) was associated with a decrease in IVRT. Increasing IVRT over a decade was associated with an increased risk of subsequent HF in participants aged <65 years (per 10 ms increase: HR 1.33; 95%CI (1.02-1.72), p = 0.034).

CONCLUSION

The cardiac time increased significantly over time. Several clinical factors accelerated these changes. An increase in IVRT was associated with an increased risk of subsequent HF in participants aged <65 years.

Cardiovascular hemodynamics in mice with tumor necrosis factor receptor-associated factor 2 mediated cytoprotection in the heart

Introduction

Many studies in mice have demonstrated that cardiac-specific innate immune signaling pathways can be reprogrammed to modulate inflammation in response to myocardial injury and improve outcomes. While the echocardiography standard parameters of left ventricular (LV) ejection fraction, fractional shortening, end-diastolic diameter, and others are used to assess cardiac function, their dependency on loading conditions somewhat limits their utility in completely reflecting the contractile function and global cardiovascular efficiency of the heart. A true measure of global cardiovascular efficiency should include the interaction between the ventricle and the aorta (ventricular-vascular coupling, VVC) as well as measures of aortic impedance and pulse wave velocity.

Methods

We measured cardiac Doppler velocities, blood pressures, along with VVC, aortic impedance, and pulse wave velocity to evaluate global cardiac function in a mouse model of cardiac-restricted low levels of TRAF2 overexpression that conferred cytoprotection in the heart.

Results

While previous studies reported that response to myocardial infarction and reperfusion was improved in the TRAF2 overexpressed mice, we found that TRAF2 mice had significantly lower cardiac systolic velocities and accelerations, diastolic atrial velocity, aortic pressures, rate-pressure product, LV contractility and relaxation, and stroke work when compared to littermate control mice. Also, we found significantly longer aortic ejection time, isovolumic contraction and relaxation times, and significantly higher mitral early/atrial ratio, myocardial performance index, and ventricular vascular coupling in the TRAF2 overexpression mice compared to their littermate controls. We found no significant differences in the aortic impedance and pulse wave velocity.

Discussion

While the reported tolerance to ischemic insults in TRAF2 overexpression mice may suggest enhanced cardiac reserve, our results indicate diminished cardiac function in these mice.

Augmented Ouabain-Induced Vascular Response Reduces Cardiac Efficiency in Mice with Migraine-Associated Mutation in the Na+, K+-ATPase α2-Isoform

Heterozygous mice (α₂^+/G301R mice) for the migraine-associated mutation (G301R) in the Na⁺,K⁺-ATPase α₂-isoform have decreased expression of cardiovascular α₂-isoform. The α₂^+/G301R mice exhibit a pro-contractile vascular phenotype associated with decreased left ventricular ejection fraction. However, the integrated functional cardiovascular consequences of this phenotype remain to be addressed in vivo. We hypothesized that the vascular response to α₂-isoform-specific inhibition of the Na⁺,K⁺-ATPase by ouabain is augmented in α₂^+/G301R mice leading to reduced cardiac efficiency. Thus, we aimed to assess the functional contribution of the α₂-isoform to in vivo cardiovascular function of wild-type (WT) and α₂^+/G301R mice. Blood pressure, stroke volume, heart rate, total peripheral resistance, arterial dP/dt, and systolic time intervals were assessed in anesthetized WT and α₂^+/G301R mice. To address rate-dependent cardiac changes, cardiovascular variables were compared before and after intraperitoneal injection of ouabain (1.5 mg/kg) or vehicle during atrial pacing. The α₂^+/G301R mice showed an enhanced ouabain-induced increase in total peripheral resistance associated with reduced efficiency of systolic development compared to WT. When the hearts were paced, ouabain reduced stroke volume in α₂^+/G301R mice. In conclusion, the ouabain-induced vascular response was augmented in α₂^+/G301R mice with consequent suppression of cardiac function.

Fetal left ventricular myocardial performance index measured at 11-14 weeks of gestation in fetuses with an increased nuchal translucency

OBJECTIVE

This study aimed to evaluate the effect of an increase in nuchal translucency (NT) thickness on the myocardial performance index (MPI) in fetuses without cardiac anomaly in the first trimester and to determine whether a difference in MPI between those with and without trisomy 21 in these fetuses could be determined.

METHODS

The study group consisted of 53 pregnancies complicated with increased NT thickness without any associated structural anomalies. Forty-six gestational age-matched pregnant women whose fetuses had normal NT thickness were enrolled as the control group.

RESULTS

In the increased NT thickness group, the mean isovolumetric relaxation time (IRT) value (0.050 ± 0.011 s) was significantly higher and the mean ejection time (ET) value (0.149 ± 0.010 s) was significantly lower than those values in the normal NT thickness group (0.045 ± 0.005 and 0.155 ± 0.009 s, p = 0.023 and p = 0.009, respectively). We found a significantly higher mean left MPI value in the increased NT thickness group (0.574 ± 0.153) versus the normal NT thickness group (0.487 ± 0.107, p < 0.001). Within the increased NT thickness group, the mean left MPI value was similar in the fetuses with normal karyotype and those with trisomy 21 (p = 0.419).

CONCLUSION

We demonstrated a significantly greater mean MPI value in the increased NT thickness group than in the normal NT thickness group. Within the increased NT thickness group, no differences in the left MPI value in the fetuses with normal karyotype and the fetuses with trisomy 21 were found.

Heart sound-derived systolic time intervals for atrioventricular delay optimization in cardiac resynchronization therapy

BACKGROUND

Phonocardiography (PCG) can be used to determine systolic time intervals (STIs) from ventricular pacing spike to the first heart sound (VS1) and from the first to the second heart sound (S1S2).

OBJECTIVE

The purpose of this study was to investigate the relations between STIs and hemodynamics during atrioventricular (AV) delay optimization of biventricular pacing (BiVP) in animals and patients.

METHODS

Five pigs with AV block underwent BiVP, while PCG was collected from an epicardial accelerometer. In 21 patients undergoing cardiac resynchronization therapy device implantation, PCG was recorded with a pulse generator-embedded microphone. Optimal AV delays derived from shortest VS1 and longest S1S2 were compared with AV delays derived from highest left ventricular pressure (LVP), maximal rate of rise in LVP, and stroke work.

RESULTS

In pigs, VS1 and S1S2 predicted the AV delays with optimal hemodynamics (highest LVP, maximal rate of rise in LVP, and stroke work) by a median error of 2-28 ms, resulting in a median loss of <2% of pump function. In patients, VS1 and S1S2 predicted the optimal AV delay by errors of 32.5 and 37.5 ms, respectively, resulting in 0.2%-0.9% lower LVP and stroke work, which were reduced to 21 and 24 ms in 8 patients with a full-capture AV delay of >180 ms.

CONCLUSION

During BiVP with varying AV delays, close relations exist between PCG-derived STIs and hemodynamic parameters. AV delays advised by PCG-derived STIs cause only a minimal loss of pump function compared with those based on invasive hemodynamic measurements.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01832493.

Preoperative Evaluation and Cardiac Risk Assessment in Vascular Surgery

We summarize epidemiologic trends, outcomes, and preoperative guidelines for vascular surgery patients from 2010 to 2022. Vascular surgery continues to evolve in technology and engineering to treat a surgical population that suffers from a high prevalence of comorbidities. Preoperative optimization seeks to characterize the burden of disease and to achieve medical control in the timeline available before surgery. Risk assessment, evaluation, optimization, and prediction of major adverse cardiac events is an evolving science where the Vascular Surgery Quality Initiative has made an impact. Ongoing investigation may demonstrate value for preoperative echocardiography, functional capacity, frailty, and mobility assessments.

Heart failure: an update from the last years and a look at the near future

In the last years, major progress occurred in heart failure (HF) management. Quadruple therapy is now mandatory for all the patients with HF with reduced ejection fraction. Whilst verciguat is becoming available across several countries, omecamtiv mecarbil is waiting to be released for clinical use. Concurrent use of potassium-lowering agents may counteract hyperkalaemia and facilitate renin-angiotensin-aldosterone system inhibitor implementations. The results of the EMPagliflozin outcomE tRial in Patients With chrOnic heaRt Failure With Preserved Ejection Fraction (EMPEROR-Preserved) trial were confirmed by the Dapagliflozin in Heart Failure with Mildly Reduced or Preserved Ejection Fraction (DELIVER) trial, and we now have, for the first time, evidence for treatment of also patients with HF with preserved ejection fraction. In a pre-specified meta-analysis of major randomized controlled trials, sodium-glucose co-transporter-2 inhibitors reduced all-cause mortality, cardiovascular (CV) mortality, and HF hospitalization in the patients with HF regardless of left ventricular ejection fraction. Other steps forward have occurred in the treatment of decompensated HF. Acetazolamide in Acute Decompensated Heart Failure with Volume Overload (ADVOR) trial showed that the addition of intravenous acetazolamide to loop diuretics leads to greater decongestion vs. placebo. The addition of hydrochlorothiazide to loop diuretics was evaluated in the CLOROTIC trial. Torasemide did not change outcomes, compared with furosemide, in TRANSFORM-HF. Ferric derisomaltose had an effect on the primary outcome of CV mortality or HF rehospitalizations in IRONMAN (rate ratio 0.82; 95% confidence interval 0.66-1.02; P = 0.070). Further options for the treatment of HF, including device therapies, cardiac contractility modulation, and percutaneous treatment of valvulopathies, are summarized in this article.

Significance of Left Ventricular Ejection Time in Primary Mitral Regurgitation

The optimal timing for mitral valve (MV) surgery in asymptomatic patients with primary mitral regurgitation (MR) remains controversial. We aimed at evaluating the relation between left ventricular ejection time (LVET) and outcome in patients with moderate or severe chronic primary MR because of prolapse. Clinical, Doppler echocardiographic, and outcome data prospectively collected from 302 patients (median age 61 [54 to 74] years, 34% women) with moderate or severe primary MR were analyzed. Patients were retrospectively stratified by quartiles of LVET. The primary end point of the study was the composite of need for MV surgery or all-cause mortality. During a median follow-up time of 66 (25th to 75th percentile, 33 to 95) months, 178 patients reached the primary end point. Patients in the lowest quartile of LVET (<260 ms) were at high risk for adverse events compared with those in the other quartiles of LVET (global p = 0.005), whereas the rate of events was similar for the other quartiles (p = NS for all). After adjustment for clinical predictors of outcome, including age, gender, history of atrial fibrillation, MR severity, and current recommended triggers for MV surgery in asymptomatic primary MR, LVET <260 ms was associated with an increased risk of events (adjusted hazard ratio 1.49, 95% confidence interval 1.03 to 2.16, p = 0.033). In conclusion, we observed that shorter LVET is associated with increased risk of adverse events in patients with moderate or severe primary MR because of prolapse. Further studies are required to investigate whether shorter LVET has a direct effect on outcomes or is solely a risk marker in primary MR.