Left Ventricular Dilatation Increases the Risk of Ventricular Arrhythmias in Patients With Reduced Systolic Function

Clinical Analysis of Myocardial Injury in Highlanders with Pulmonary Hypertension

Background: Pulmonary hypertension (PH) is a prevalent adverse cardiovascular event at high-altitude environments. Prolonged exposure to high altitudes may result in myocardial injury, which is associated with poor clinical outcomes. This study aims to investigate the clinical characteristics of myocardial injury in patients with PH at high altitude. Methods: Consecutive patients admitted to a general tertiary hospital at the altitude of 3,650 m were selected into this retrospective study. Clinical and biochemical data were collected, as well as based on cardiac troponin I (cTnI) and echocardiography, patients were divided into myocardial injury group and non-myocardial injury group. Results: A total of 231 patients were enrolled, among whom 29 (12.6%) had myocardial injury. We found that body mass index, left ventricular end-diastolic dimension, and serum level of creatine kinase-MB (CK-MB) in myocardial injury group were significantly higher than non-myocardial injury group. Spearman correlation analysis revealed that cTnI has a significant positive correlation with CK-MB and lactic dehydrogenase instead of aspartate aminotransferase. A receiver operating characteristic curve was drawn to demonstrate that CK-MB could significantly predict the occurrence of myocardial injury with an area under the curve of 0.749, and a level of 3.035 (sensitivity = 59.3%, specificity = 90.5%) was optimal cutoff value. Conclusion: The incidence of myocardial injury in highlanders with PH is significant. CK-MB, as a convenient and efficient marker, has been found to be closely associated with cTnI and plays a predictive role in the occurrence of myocardial injury with PH in individuals exposed to high altitude.

Cardiac dysfunction in dialysing adults with end-stage kidney disease is associated with exercise intolerance: A pilot observational study

People with end-stage kidney disease (ESKD) often exhibit impaired cardiac structure and function, which may contribute to poor exercise capacity. This study used multimodal exercise testing to investigate the central and peripheral mechanisms of exercise limitation in adults with ESKD, also comparing in-centre hemodialysis (ICHD) to home hemodialysis (HHD). Seventeen adults (55.5 ± 14.5 years; n = 14 male; n = 12 HHD) participated. Resting cardiac examinations, followed by submaximal cycling cardiopulmonary exercise testing (CPET) and functional exercise testing, revealed cardiac structural abnormalities (increased left ventricular mass) and cardiac injury. Aerobic fitness in adults with ESKD was low, with pulmonary oxygen uptake (V̇O2) at the gas exchange threshold (GET) occuring at 39 ± 8% predicted V̇O2peak. O2 pulse, an estimate of stroke volume (SV), was higher in HHD at rest (p = 0.05, ES = 0.58) and during unloaded cycling (p = 0.05, ES = 0.58) compared to ICHD. However, thoracic bioreactance derived SV at the GET was significantly higher in adults receiving ICHD versus HHD (p = 0.01, ES = 0.74). In adults with ESKD, cardiac output was positively associated with V̇O2 at the GET (r = 0.61, p = 0.04). This study highlights prevalent exercise dysfunction in adults with ESKD undergoing dialysis, with potential distinct differences between in-centre and home hemodialysis, mechanistically linked to underlying cardiac abnormalities.

Prognostic impact of implantable cardioverter defibrillators and associated adverse events in patients with continuous flow left ventricular assist devices

Objectives

Implantation of implantable cardioverter defibrillators (ICD) reduces the risk of all-cause mortality in symptomatic heart failure (HF) patients with severe left ventricular (LV) dysfunction. Nevertheless, the prognostic impact of ICD therapy in continuous flow left ventricular assist device (LVAD) recipients remains controversial.

Methods

162 consecutive HF patients, who underwent LVAD implantation at our institution between 2010 and 2019, were categorized according to the presence (n = 94, ICD-group) or absence (n = 68, Control-group) of ICDs. Apart from clinical baseline and follow-up parameters, adverse events (AEs) related to ICD therapy and overall survival rates were retrospectively analyzed.

Results

Out of 162 consecutive LVAD recipients 79 patients (48.8%) were preoperatively categorized as Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) profile ≤2. The prevalence of severe HF symptoms and preoperative use of short-term circulatory support devices (54.4% vs. 13.8%, p < 0.001) was higher within the Control-group, although baseline severity of LV and RV dysfunction was similar. Apart from an increased prevalence of perioperative right heart failure (RHF) within the Control-group (45.6% vs. 17.0%; p < 0.001), procedural characteristics and perioperative outcome were similar. Overall-survival during a median follow-up of 14 (3.0-36.5) months was similar within both groups (p = 0.46). During the first 2 years after LVAD implantation 53 ICD-related AEs occurred within the ICD-group. Thereof, lead-dysfunction occurred in 19 patients and unplanned ICD-reintervention in 11 patients. Furthermore, in 18 patients appropriate shocks without loss of consciousness occurred, whereas inappropriate shocks occurred in 5 patients.

Conclusion

ICD therapy in LVAD recipients was not associated with a survival benefit or reduced morbidity after LVAD implantation. Conservative ICD-programming seems to be justified to avoid ICD-related complications and "awake shocks" after LVAD implantation.

Increasing efficiency of SVMp+ for handling missing values in healthcare prediction

Missing data presents a challenge for machine learning applications specifically when utilizing electronic health records to develop clinical decision support systems. The lack of these values is due in part to the complex nature of clinical data in which the content is personalized to each patient. Several methods have been developed to handle this issue, such as imputation or complete case analysis, but their limitations restrict the solidity of findings. However, recent studies have explored how using some features as fully available privileged information can increase model performance including in SVM. Building on this insight, we propose a computationally efficient kernel SVM-based framework (l2-SVMp+) that leverages partially available privileged information to guide model construction. Our experiments validated the superiority of l2-SVMp+ over common approaches for handling missingness and previous implementations of SVMp+ in both digit recognition, disease classification and patient readmission prediction tasks. The performance improves as the percentage of available privileged information increases. Our results showcase the capability of l2-SVMp+ to handle incomplete but important features in real-world medical applications, surpassing traditional SVMs that lack privileged information. Additionally, l2-SVMp+ achieves comparable or superior model performance compared to imputed privileged features.

DNA Methylation Analysis Identifies Novel Epigenetic Loci in Dilated Murine Heart upon Exposure to Volume Overload

Left ventricular (LV) dilatation, a prominent risk factor for heart failure (HF), precedes functional deterioration and is used to stratify patients at risk for arrhythmias and cardiac mortality. Aberrant DNA methylation contributes to maladaptive cardiac remodeling and HF progression following pressure overload and ischemic cardiac insults. However, no study has examined cardiac DNA methylation upon exposure to volume overload (VO) despite being relatively common among HF patients. We carried out global methylome analysis of LV harvested at a decompensated HF stage following exposure to VO induced by aortocaval shunt. VO resulted in pathological cardiac remodeling, characterized by massive LV dilatation and contractile dysfunction at 16 weeks after shunt. Although methylated DNA was not markedly altered globally, 25 differentially methylated promoter regions (DMRs) were identified in shunt vs. sham hearts (20 hypermethylated and 5 hypomethylated regions). The validated hypermethylated loci in Junctophilin-2 (Jph2), Signal peptidase complex subunit 3 (Spcs3), Vesicle-associated membrane protein-associated protein B (Vapb), and Inositol polyphosphate multikinase (Ipmk) were associated with the respective downregulated expression and were consistently observed in dilated LV early after shunt at 1 week after shunt, before functional deterioration starts to manifest. These hypermethylated loci were also detected peripherally in the blood of the shunt mice. Altogether, we have identified conserved DMRs that could be novel epigenetic biomarkers in dilated LV upon VO exposure.

Machine Learning-Based Phenomapping in Patients with Heart Failure and Secondary Prevention Implantable Cardioverter-Defibrillator Implantation: A Proof-of-Concept Study

Background

Previous studies have failed to implement risk stratification in patients with heart failure (HF) who are eligible for secondary implantable cardioverter-defibrillator (ICD) implantation. We aimed to evaluate whether machine learning-based phenomapping using routinely available clinical data can identify subgroups that differ in characteristics and prognoses.

Methods

A total of 389 patients with chronic HF implanted with an ICD were included, and forty-four baseline variables were collected. Phenomapping was performed using hierarchical k-means clustering based on factor analysis of mixed data (FAMD). The utility of phenomapping was validated by comparing the baseline features and outcomes of the first appropriate shock and all-cause death among the phenogroups.

Results

During a median follow-up of 2.7 years for device interrogation and 5.1 years for survival status, 142 (36.5%) first appropriate shocks and 113 (29.0%) all-cause deaths occurred. The first 12 principal components extracted using the FAMD, explaining 60.5% of the total variability, were left for phenomapping. Three mutually exclusive phenogroups were identified. Phenogroup 1 comprised the oldest patients with ischemic cardiomyopathy; had the highest proportion of diabetes mellitus, hypertension, and hyperlipidemia; and had the most favorable cardiac structure and function among the phenogroups. Phenogroup 2 included the youngest patients, mostly those with non-ischemic cardiomyopathy, who had intermediate heart dimensions and function, and the fewest comorbidities. Phenogroup 3 had the worst HF progression. Kaplan-Meier curves revealed significant differences in the first appropriate shock (p = 0.002) and all-cause death (p < 0.001) across the phenogroups. After adjusting for medications in Cox regression, phenogroups 2 and 3 displayed a graded increase in appropriate shock risk (hazard ratio [HR] 1.54, 95% confidence interval [CI] 1.03-2.28, p = 0.033; HR 2.21, 95% CI 1.42-3.43, p < 0.001, respectively; p for trend < 0.001) compared to phenogroup 1. Regarding mortality risk, phenogroup 3 was associated with an increased risk (HR 2.25, 95% CI 1.45-3.49, p < 0.001). In contrast, phenogroup 2 had a risk (p = 0.124) comparable with phenogroup 1.

Conclusions

Machine-learning-based phenomapping can identify distinct phenotype subgroups in patients with clinically heterogeneous HF with secondary prophylactic ICD therapy. This novel strategy may aid personalized medicine for these patients.

Prognostic Implications of Left Ventricular Ejection Fraction and Left Ventricular End-Diastolic Diameter on Clinical Outcomes in Patients with ICD

Background: Left ventricular ejection fraction (LVEF) is a suboptimal indicator of risk stratification for patients with an implantable cardioverter defibrillator (ICD). Studies have shown that left ventricular end-diastolic diameter (LVEDD) was associated with all-cause mortality and ventricular arrhythmias. We examined the quantified prognostic value of LVEF and LVEDD for clinical outcomes, respectively. Method: This study retrospectively enrolled patients with ICD implantation in a single center. The associations between LVEF or LVEDD and all-cause mortality and appropriate shocks were analyzed using Cox regression and Fine-gray competing risk regression, respectively. Result: During a median follow up of 59.6 months, 168/630 (26.7%) patients died. LVEF and LVEDD were strongly associated with all-cause mortality (LVEF per 10%: HR 0.77, 95%CI 0.64−0.93, p = 0.006; LVEDD per 10 mm: HR 1.54, 95%CI 1.27−1.85, p < 0.001). After a median interrogation time of 37.1 months, 156 (24.8%) patients received at least one shock. LVEF was not associated with appropriate shock, whereas larger LVEDD (per 10 mm) was significantly associated with a higher risk of shock (HR: 1.27, 95%CI 1.06−1.52, p = 0.008). The addition of LVEF or LVEDD to clinical factors provided incremental prognostic value and discrimination improvement for all-cause mortality, while only the addition of LVEDD to clinical factors improved prognostic value for shock intervention. Conclusions: Baseline LVEF and LVEDD show a linear relationship with all-cause mortality in patients with ICD. However, whereas LVEF is not associated with shock, a linear relationship exists between LVEDD and appropriate shock. LVEDD adds more predictive value in relation to all-cause mortality and appropriate shocks than LVEF.

Dilated Left Ventricular End-Diastolic Diameter Is a New Risk Factor of Acute Kidney Injury Following Coronary Angiography

Purpose

Left ventricular end-diastolic diameter (LVEDD) is a common indicator in echocardiogram, and dilated LVEDD was correlated with left ventricular insufficiency. However, it is uncertain whether dilated LVEDD is associated with increasing the risk of contrast-associated acute kidney injury (CA-AKI) in patients with coronary artery disease (CAD).

Patients and Methods

We enrolled 8,189 patients with CAD undergoing coronary angiography (CAG) between January 2007 and December 2018. Patients were divided into two groups according to the LVEDD length (normal LVEDD: men: LVEDD ≤56 mm, women: LVEDD ≤51 mm; dilated LVEDD: men: LVEDD >56 mm, women: LVEDD >51 mm). The endpoints were CA-AKI⁰³⁵⁰ and CA-AKI⁰⁵²⁵ (CA-AKI⁰³⁵⁰: an increase in the serum creatinine (Scr) level by >0.3 mg/dl or >50% within the first 48 h after CAG; CA-AKI⁰⁵²⁵: an absolute Scr increase ≥ 0.5 mg/dl or a relative increase ≥ 25% within 72 h after contrast medium exposure). In-hospital dialysis, 30-day mortality, and 1-year mortality were contained as well. Univariate and multivariable logistic regressions were used to assess the association between LVEDD and CA-AKI.

Results

Among 8,189 participants (men: 76.6%, mean age: 64.4 ± 10.7 years), 1,603 (19.6%) presented with dilated LVEDD. In addition, the dilated LVEDD group indicated an elevation of CA-AKI⁰³⁵⁰ (12.4 vs. 6.2%, p < 0.001) and CA-AKI⁰⁵²⁵ (15.0 vs. 8.8%; p < 0.001) when compared with the normal group. According to multivariable logistic analysis, dilated LVEDD was an independent predictor of CA-AKI⁰³⁵⁰ [adjusted odds ratio (aOR): 1.31; 95% confidence interval (CI): 1.06–1.61, p = 0.010) and CA-AKI⁰⁵²⁵ (aOR: 1.32; 95% CI: 1.04–1.67; p = 0.020).

Conclusion

In conclusion, these results demonstrated that the dilated LVEDD was a significant and independent predictor of CA-AKI following CAG in patients with CAD. Further verifications are needed to verify the association between LVEDD and CA-AKI.

Left Ventricular End-Diastolic Dimension and Clinical Outcomes After Centrifugal Flow Left Ventricular Assist Device Implantation

The impact of preoperative end-diastolic left ventricular dimension (preLVEDD) on long-term outcomes with centrifugal continuous-flow left ventricular assist device (CF-LVAD) is not well established. Accordingly, we performed an analysis of the Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) registry to study this relationship. All patients with centrifugal CF-LVAD in the INTERMACS registry from June 2006 to December 2017 were screened. The final study group consisted of 3,304 patients. After a median follow-up of 9.0 months (interquartile range [IQR], 4.2-18.8 months), 2,596 (79%) patients were alive. After adjusting for significant covariates, increased preLVEDD was associated with lower mortality (hazard ratio [HR], 0.91; 95% confidence interval [CI], 0.84-0.98; p = 0.01), stroke (HR, 0.85; 95% CI, 0.77-0.93; p < 0.001), and gastrointestinal bleeding (HR, 0.88; 95% CI, 0.80-0.97; p = 0.01), although there were more arrhythmias (HR, 1.14; 95% CI, 1.05-1.24; p = 0.003). Our study suggests that preLVEDD is an independent predictor of mortality and adverse events in patients treated with centrifugal CF-LVAD. preLVEDD should be considered an important preimplant variable for risk stratification when considering a CF-LVAD.

Left Ventricular Structure is Associated with Postoperative Death After Coronary Artery Bypass Grafting in Patients with Heart Failure with Reduced Ejection Fraction

Background

The relationship between abnormal left ventricular (LV) structure and adverse outcomes has been confirmed in diverse patient groups in previous studies. However, it remains uncertain whether LV structure has predictive implications in heart failure with reduced ejection fraction (HFrEF) patients with coronary artery bypass grafting (CABG).

Methods

This study retrospectively enrolled patients who had HFrEF and underwent CABG between January 2013 and July 2019. According to LV hypertrophy (LVH) and LV enlargement (LVE) assessed by echocardiography, patients were classified into four LV structure types: (-)LVH/(-)LVE, (+)LVH/(-)LVE, (-)LVH/(+)LVE, and (+)LVH/(+)LVE.

Results

A total of 435 consecutive patients (mean age: 59.4 ± 9.6 years; 14.9% female) were enrolled in the present study. Examined independently, either LVH (p < 0.001) or LVE (p < 0.001) was independently associated with postoperative mortality in multivariate analysis. When LVH and LVE were analyzed in combination, the risk of mortality after CABG was lowest in (-)LVH/(-)LVE and increased with (+)LVH/(-)LVE (odds ratio [OR]: 7.525; 95% confidence interval [CI]: 1.827–30.679, p = 0.004), (-)LVH/(+)LVE (OR: 7.253; 95% CI: 1.950–27.185, p = 0.003), and (+)LVH/(+)LVE (OR: 9.547; 95% CI: 2.726–34.805, p < 0.001), independent of other risk factors. Adding LV structural types to the baseline model gained an incremental effect on the predictive value for postoperative mortality (AUC: baseline model, 0.838 vs baseline model + LV structural types, 0.901, p for comparison = 0.010; category‐free net reclassification improvement (NRI): 0.764, p < 0.001; integrated discrimination improvement (IDI): 0.061, p = 0.007).

Conclusion

LVH and LVE were associated with an increased risk of postoperative mortality after CABG in patients with HFrEF. Categorizing LV structural patterns with LVH and LVE contributes to risk stratification and provides incremental predictive ability. Routine echocardiographic assessment of LVH and LVE is needed in clinical practice.

Midterm outcome of off-pump CABG for severe LV dysfunction-Does LV size and function predict their midterm outcome?

BACKGROUND

The superiority of surgical revascularization in ischemic cardiomyopathy is established beyond doubt, and off-pump CABG (OP-CABG) is a safe way of revascularization in this high-risk subset. Data on the effect of postoperative ventricular function and size on their midterm outcome is scarce.

MATERIALS AND METHODS

A retrospective study was done on 211 consecutive patients with severe LV dysfunction who underwent OP-CABG from January 2017 to December 2018. Data were collected from the institutional database. Their operative and midterm outcomes were statistically analyzed.

RESULTS

The mean age of the cohort was 58.4 ± 8.3 years. An average number of grafts was 3.1 ± 0.8 (cumulative intended number of grafts-3). Operative mortality was 10.9%. Preoperative NYHA class (p < .0001; OR, 19.72) and postoperative IABP insertion (p < .008; OR, 88.75) were independent predictors of operative mortality. The mean follow-up period was 3.14 ± 0.07 years, was 97.4% complete with cardiac mortality of 5.8%. Postoperative LVEF (p = .002; OR, 0.868) and LV dimensions (systole & diastole) (p = .013, OR = 1.182 and p = .036, OR = 1.184, respectively) were independent predictors of midterm mortality. Midterm major adverse cardiovascular event-free survival of operative survivors was 89%. There was no correlation between postoperative LV dimension and NYHA status(p > .05). Myocardial viability was not associated with early (p = .17) or midterm mortality (p = .676).

CONCLUSION

OP-CABG can achieve complete revascularization in patients with severe LV dysfunction with good midterm outcomes, albeit with high early operative mortality. Postoperative change in LV dimension and EF are predictors of midterm mortality.

Baseline and Dynamic Risk Predictors of Appropriate Implantable Cardioverter Defibrillator Therapy

Background Current approaches fail to separate patients at high versus low risk for ventricular arrhythmias owing to overreliance on a snapshot left ventricular ejection fraction measure. We used statistical machine learning to identify important cardiac imaging and time-varying risk predictors. Methods and Results Three hundred eighty-two cardiomyopathy patients (left ventricular ejection fraction ≤35%) underwent cardiac magnetic resonance before primary prevention implantable cardioverter defibrillator insertion. The primary end point was appropriate implantable cardioverter defibrillator discharge or sudden death. Patient characteristics; serum biomarkers of inflammation, neurohormonal status, and injury; and cardiac magnetic resonance-measured left ventricle and left atrial indices and myocardial scar burden were assessed at baseline. Time-varying covariates comprised interval heart failure hospitalizations and left ventricular ejection fractions. A random forest statistical method for survival, longitudinal, and multivariable outcomes incorporating baseline and time-varying variables was compared with (1) Seattle Heart Failure model scores and (2) random forest survival and Cox regression models incorporating baseline characteristics with and without imaging variables. Age averaged 57±13 years with 28% women, 66% white, 51% ischemic, and follow-up time of 5.9±2.3 years. The primary end point (n=75) occurred at 3.3±2.4 years. Random forest statistical method for survival, longitudinal, and multivariable outcomes with baseline and time-varying predictors had the highest area under the receiver operating curve, median 0.88 (95% CI, 0.75-0.96). Top predictors comprised heart failure hospitalization, left ventricle scar, left ventricle and left atrial volumes, left atrial function, and interleukin-6 level; heart failure accounted for 67% of the variation explained by the prediction, imaging 27%, and interleukin-6 2%. Serial left ventricular ejection fraction was not a significant predictor. Conclusions Hospitalization for heart failure and baseline cardiac metrics substantially improve ventricular arrhythmic risk prediction.

The cardiothoracic ratio: a neglected preoperative risk-stratified method for patients with rheumatic heart disease undergoing valve replacement surgery

OBJECTIVES

It is common for patients with rheumatic heart disease to have an enlarged heart. We investigated the prognostic value of cardiothoracic ratio (CTR) in patients with rheumatic heart disease undergoing valve replacement surgery.

METHODS

A total of 1772 patients were divided into 4 groups based on the quartiles of preoperative CTR: <0.56 (n = 349), 0.56-0.61 (n = 488), 0.61-0.66 (n = 449) and ≥0.66 (n = 486). The CTR was measured from postero-anterior chest radiographs. We then investigated the association between the CTR and adverse outcomes.

RESULTS

In-hospital mortality was 4.0% (71/1772). Analyses of receiver operating characteristic curves showed that, at a cut-off of 0.6, the CTR exhibited 66.2% sensitivity and 64.0% specificity for detecting in-hospital death (area under curve 0.671, P < 0.001). The prevalence of in-hospital death was 7.1% in males with a CTR >0.6, which was significantly higher in males without a CTR. A similar result was observed in females (1.9 vs 5.1%, P = 0.004). Multivariable regression showed that a CTR >0.6 was an independent predictor of in-hospital (odds ratio 2.36, P = 0.005) and 1-year mortality (hazard ratio 2.06, P = 0.006). Kaplan-Meier curves, for the cumulative rate of 1-year mortality among groups, indicated that the risk of death was increased if the CTR >0.6 (log-rank 16.36, P < 0.001).

CONCLUSIONS

CTR, as a simple and reproducible indicator, was identified as a prognostic factor for predicting poor outcomes in patients with rheumatic heart disease undergoing valve replacement surgery.

Prognostic impacts of dynamic cardiac structural changes in heart failure patients with preserved left ventricular ejection fraction

Aims

We aimed to examine temporal changes in left ventricular (LV) structures and their prognostic impacts in patients with heart failure (HF) and preserved ejection fraction (HFpEF).

Methods and results

In the Chronic Heart Failure Analysis and Registry in the Tohoku District‐2 (CHART‐2) study (n = 10 219), we divided 2698 consecutive HFpEF patients (68.9 ± 12.2 years, 32.1% female) into three groups by LV hypertrophy (LVH) and enlargement (LVE) at baseline: (−)LVH/(−)LVE (n = 989), (+)LVH/(−)LVE (n = 1448), and (+)LVH/(+)LVE (n = 261). We examined temporal changes in LV structures and their prognostic impacts during a median 8.7‐year follow‐up. From (−)LVH/(−)LVE, (+)LVH/(−)LVE to (+)LVH/(+)LVE at baseline, the incidence of the primary outcome, a composite of cardiovascular death or HF admission, significantly increased. Among 1808 patients who underwent echocardiography at both baseline and 1 year, we noted substantial group transitions from baseline to 1 year; the transition rates from (−)LVH/(−)LVE to (+)LVH/(−)LVE, from (+)LVH/(−)LVE to (−)LVH/(−)LVE, from (+)LVH/(−)LVE to (+)LVH/(+)LVE, and from (+)LVH/(+)LVE to (+)LVH/(−)LVE were 27% (182/671), 22% (213/967), 6% (59/967), and 26% (44/170), respectively. In the univariable Cox proportional hazard model, patients who transitioned from (+)LVH/(−)LVE to (+)LVH/(+)LVE or remained in (+)LVH/(+)LVE had the worst subsequent prognosis [hazard ratio (HR) 4.65, 95% confidence interval (CI) 3.09–6.99, P < 0.001; HR 4.01, 95% CI 2.85–5.65, P < 0.001, respectively], as compared with those who remained in (−)LVH/(−)LVE. These results were unchanged after adjustment for the covariates including baseline LV ejection fraction (LVEF) and 1‐year LVEF change.

Conclusion

In HFpEF patients, LV structures dynamically change over time with significant prognostic impacts, where patients who develop LVE with LVH have the worst prognosis.

Structural and Physiological Imaging to Predict the Risk of Lethal Ventricular Arrhythmias and Sudden Death

Identifying patients at risk of sudden cardiac death remains a major challenge in cardiovascular medicine. Advances in cardiovascular imaging have identified several anatomic and functional variables that can be quantified as continuous variables to predict the risk of developing lethal ventricular tachyarrhythmias in patients with depressed left ventricular (LV) systolic function. Some, such as LV mass, volume, and the dyssynchrony of contraction, can be derived from currently available echocardiographic and nuclear imaging modalities. Others require advanced cardiac imaging modalities with quantification of myocardial scar with gadolinium-enhanced cardiac magnetic resonance and myocardial sympathetic denervation using norepinephrine analogs and positron emission tomography or single-photon emission computed tomography offering the most promise. There is an immediate need to develop a sequential cost-effective approach that capitalizes on readily available clinical information complemented with advanced imaging modalities in selected patients to improve risk stratification for arrhythmic death beyond LV ejection fraction.

Effect of Successful Edge-to-Edge Mitral Valve Repair on Ventricular Arrhythmic Burden in Patients With Functional Mitral Regurgitation and Implantable Cardiac Devices

Significant mitral regurgitation (MR) may be present in up to half of patients with heart failure (HF) and it is associated with adverse cardiac remodeling and myocardial stretch. These are potential triggers for ventricular arrhythmias (VA) in patients with HF, and therefore MR may enhance electrical ventricular vulnerability. Our aim was to evaluate VA burden before and after percutaneous mitral valve repair (PMVR) in patients with implantable cardiac devices. We conducted a prospective registry of all consecutive patients (n = 34, age 69.0 ± 12.2 years, 77% male) with significant functional mitral regurgitation (FMR) who underwent MitraClip implantation in 2 centers between June 2014 and July 2018. VA burden was defined as the total number of events during device follow-up before and after PMVR. Among patients presenting VA during follow-up before or after PMVR, device success at hospital discharge was related to a significant reduction in the incidence of Nonsustained ventricular tachycardia (VT, p = 0.002) and any sustained VT or rapid VT/ventricular fibrillation (p = 0.034). Regarding implantable cardiac defibrillator (ICD) therapies, successful PMVR was related to a reduction in incidence of either antitachycardia pacing or appropriate shocks (p = 0.045) and in the occurrence of any defibrillation shocks (p = 0.045). Overall, effective repair lead to a significant reduction in the VA burden, with a significant decrease in the occurrence of any VA (p = 0.004) and any ICD therapies (p = 0.045). In conclusion, device success after PMVR was related to a reduction in overall arrhythmic burden and ICD therapies in our cohort.

Overlapping Phenotypes and Degree of Ventricular Dilatation Are Associated with Severity of Systolic Impairment and Late Gadolinium Enhancement in Non-Ischemic Cardiomyopathies

Background

Dilatation and other infrastructural rearrangements of the left ventricle are connected with poor prognosis. The aim of our study was to analyze the overlapping phenotypes and dilatation of the ventricle on impairment of systolic function and existence of late gadolinium enhancement (LGE).

Material/Methods

Consecutive sample of cases with dilated left ventricle due to non-ischemic cardiomyopathy and healthy controls were included from our cardiac magnetic resonance imaging (CMR) database for a period of 3 years (n=1551 exams).

Results

The study included 127 patients; 30 (23.6%) with dilated cardiomyopathy (DCM); 30 (23.6%) with left ventricular non-compaction (LVNC); 13 (10.2%) with hypertrophic cardiomyopathy (HCM), and 50 (39.4%) controls. Overlapping phenotypes were found in 48 (37.8%) of the studied cases. Odds for impairment of systolic function in connection with overlapping phenotypes were estimated at 7.8 (95%-CI: 3.4–17.6), (p<0.001). There were significant differences in geometric parameters for patients with overlapping phenotypes vs. controls, as follows: left ventricle end-diastolic dimension(LVEDD)=6.6±0.8 vs. 5.6±1.0 cm (p<0.001); left ventricular ejection fraction (LVEF)=39.3±14.0 vs. 52.1±16.1 (p<0.001); and existence of LGE 36 (75.0%) vs. 21 (26.6%), (p<0.001), respectively. Overlapping phenotypes correlated with LVEDD (Spearman’s-Rho-CC)=0.521, p<0.001; LVEF (Rho-CC)=−0.447, p<0.001 and LGE (Rho-CC)=0.472, p<0.001.

Conclusions

This study found there are many patients with overlapping phenotypes among NICMPs with dilated left ventricles. Overlapping phenotype was associated with greater LVEDD, lesser systolic function, and commonly existing LGE, which all impose increased cardiovascular risk. Linear midventricular LGE stripe was the most powerfully connected with loss of systolic function.

Left ventricular sphericity index analysis for the prediction of appropriate implantable cardioverter-defibrillator therapy

BACKGROUND

Implantable cardioverter-defibrillator (ICD) is the most effective therapy currently available to prevent sudden cardiac death (SCD) in patients with left ventricular (LV) dysfunction. Although LV ejection fraction (LVEF) is an excellent marker of SCD in these patients, determining other predictors might help to identify patients who will be benefit more from device implantation. The purpose of this study was to determine whether abnormal LV sphericity index (SI) in transthoracic echocardiography is associated with appropriate ICD therapy in these patients.

METHODS

A total of 140 patients with primary ICD implantation (mean age 62.59 ± 11.36 years; 98 [70%] male) were included. The patients were classified into "no ICD therapy" or "ICD therapy" group according to the information of their devices for a maximum of 2 previous years. In four-chamber view image of transthoracic echocardiography, SI was calculated by dividing the major-axis dimension to minor-axis dimension of LV in both groups.

RESULTS

Compared with patients with no ICD therapy, patients in ICD therapy group had lower LVEF (31.36 ± 9.58 vs 23.24 ± 6.03, P = 0.0001) and lower SI (1.79 ± 0.29 vs 1.57 ± 0.32, P = 0.0001). In multivariant logistic regression analysis, the SI of ≤1.58 was associated with fourfold increase of appropriate ICD therapy, even after adjusting for LVEF (odds ratio, 4.08; 95% confidence interval, 1.71-9.75; P = 0.02).

CONCLUSION

Simple echocardiographic sphericity dimension index as a marker of cardiac remodeling may be an important predictor of appropriate ICD therapy in patients with primary prevention ICDs and may provide additive risk stratification in patients with LV systolic dysfunction.

Elevated LV Mass and LV Mass Index Sign on the Athlete's ECG: Athletes' Hearts are Prone to Ventricular Arrhythmia

OBJECTIVES

Intense exercise elevates all heart chambers' dimensions, left ventricular mass (LV mass), and left ventricular mass index (LV mass index). The relationship between increased ventricular arrhythmias and sudden cardiac death with LV dilatation and elevated LV mass has been previously demonstrated. We investigated whether sports-related LV dilatation and elevated LV mass and LV mass index cause an increase in ventricular repolarization heterogeneity.

PATIENTS AND METHODS

This prospective observational study recruited 565 participants. There were 226 (female: 28) athletes and 339 (female: 45) healthy controls between 17 and 42 years of age. They were evaluated using 12-lead-electrocardiography and transthoracic echocardiography. Electrocardiograms were obtained at a rate of 50 mm/s and an amplitude of 10 mV, including at least 3 QRS complexes for each derivation. They were taken with 12 standard deviations. Transmural dispersion of repolarization indexes (TDR) (Tp-Te interval, Tp-Te/QT ratio and Tp-Te/QTc ratio, Tp-Te(d)) were measured from precordial derivations. Measurements weretakenwith a program which was generated with MATLAB codes.

RESULTS

Tp-Te interval, Tp-Te/QT ratio, Tp-Te/QTc ratio, Tp-Te(d), PW (posterior wall thickness), IVS (interventricular septal thickness), LVEDD (left ventricular end-diastolic diameter), LV mass (left ventricular mass), and LV mass index (left ventricular mass index) for the athlete group were significantly higher than for the control group. Correlation analyses revealed that TDR indexes significantly correlated with PW, IVS, LVEDD, LV mass, and LV mass index.

CONCLUSION

LV mass and LV mass index increase in well-trained athletes, and this increase leads to an increase in TDR indexes. The increased frequency of ventricular arrhythmia and sudden cardiac death may be explained with increasing ventricular repolarization heterogeneity in these individuals.

Predictors and implications of early left ventricular ejection fraction improvement in new-onset idiopathic nonischemic cardiomyopathy with narrow QRS complex: A NEOLITH substudy

BACKGROUND

Predictors and implications of early left ventricular ejection fraction (LVEF) improvement with guideline-directed medical therapy (GDMT) in new-onset idiopathic nonischemic cardiomyopathy (NICM) with narrow QRS complex are not well described. The objectives were to describe predictors of LVEF improvement after 3 months on GDMT and adverse cardiac events based on post-GDMT LVEF status (≤35% vs. >35%).

METHODS

A retrospective cohort study was performed in subjects with new-onset NICM, LVEF ≤35%, and narrow QRS complex. Associations for baseline variables with post-GDMT LVEF improvement and absolute change in LVEF (∆LVEFGDMT ) were assessed. Cox proportional hazards models assessed associations for post-GDMT LVEF status with adverse cardiac events.

RESULTS

In 70 subjects, 31 (44%) had post-GDMT LVEF ≤35% after a median follow-up time of 97.5 days (interquartile range, 84-121 days). In final multivariable models, severely dilated left ventricular end-diastolic diameter (LVEDD), compared with normal LVEDD, strongly predicted post-GDMT LVEF ≤35% (odds ratio, 7.77; 95% confidence interval [CI], 1.39-43.49; p = .02) and ∆LVEFGDMT (β = -15.709; standard error = 4.622; p = .001). Subjects with post-GDMT LVEF ≤35% were more likely to have adverse cardiac events over a median follow-up time of 970.5 days (unadjusted hazard ratio, 2.15; 95% CI, 0.93-4.96; p = .07). In the post-GDMT LVEF ≤35% group, 9 of 26 subjects (35%) had long-term LVEF > 35%.

CONCLUSION

In new-onset NICM with narrow QRS complex, nondilated LVEDD predicted early LVEF improvement. Those with post-GDMT LVEF ≤35% had higher risk of adverse cardiac events, but a substantial proportion demonstrated continued long-term LVEF improvement.

Long-Term Antiarrhythmic Effects of Thrombolytic Therapy in Pulmonary Embolism

BACKGROUND

The role of thrombolytic therapy in acute pulmonary embolism patients is still controversial considering the occurrence of arrhythmias. Short-term effects of thrombolytics are well-known whereas long-term effects on cardiac electrophysiology have not been reported before. The objective of our study was to assess the arrhythmic differences in pulmonary embolism patients who received thrombolytics followed by anticoagulation or anticoagulation alone.

METHODS

Sixty patients who received thrombolytic therapy followed by anticoagulation (group 1) and 60 patients who received anticoagulation alone (group 2) were included in this retrospective, single-centre observational study. Twenty-four-hour ambulatory electrocardiography was performed 31 ± 9 months after pulmonary embolism hospitalisation in order to compare arrhythmias originating from both ventricles and atria.

RESULTS

The age and gender distribution of the patients were statistically similar. Ventricular arrhythmias were found to be the same between t-PA and non t-PA groups. All types of atrial arrhythmias were found to be increased in non t-PA group even though left and right atrial volume indexes were statistically identical between the two groups.

CONCLUSION

In long-term pulmonary embolism, follow-up thrombolytic therapy was demonstrated to have atrial antiarrhythmic effects.

Left Ventricular Geometry and Risk of Sudden Cardiac Arrest in Patients With Severely Reduced Ejection Fraction

Background

Recent reports indicate that specific left ventricular (LV) geometric patterns predict recurrent ventricular arrhythmias in patients with implantable cardioverter‐defibrillators and reduced left ventricular ejection fraction (LVEF). However, this relationship has not been evaluated among patients at risk of sudden cardiac arrest (SCA) in the general population.

Methods and Results

Adult SCA cases from the Oregon Sudden Unexpected Death Study were compared with geographic controls with no prior history of SCA. Archived echocardiograms performed closest and prior to the SCA event were reviewed. LV geometry was defined as normal (normal LV mass index [LVMI] and relative wall thickness [RWT]), concentric remodeling (normal LVMI and increased RWT), concentric hypertrophy (increased LVMI and RWT), or eccentric hypertrophy (increased LVMI and normal RWT). Analysis was restricted to those with LVEF ≤40%. A total of 246 subjects were included in the analysis. SCA cases (n=172, 68.6±13.3 years, 78% male), compared to controls (n=74, 66.8±12.1 years, 73% male), had lower LVEF (29.4±7.9% vs 30.8±6.3%, P=0.021). Fewer cases presented with normal LV geometry (30.2% vs 43.2%, P=0.048) and more with eccentric hypertrophy (40.7% vs 25.7%, P=0.025). In a multivariate model, eccentric hypertrophy was independently predictive of SCA (OR 2.15, 95% CI 1.08–4.29, P=0.03).

Conclusions

Eccentric LV hypertrophy was independently associated with increased risk of SCA in subjects with EF ≤40%. These findings, now consistent between device‐implanted and non‐implanted populations, indicate the potential of improving SCA risk stratification from the same noninvasive echocardiogram at no additional cost.