Cardiovascular disease risk: it is complicated, but race and ethnicity are key, a Bayesian network analysis.

Background: Cardiovascular diseases are the leading cause of morbidity and mortality in the United States. Despite the complexity of cardiovascular disease etiology, we do not fully comprehend the interactions between non-modifiable factors (e.g., age, sex, and race) and modifiable risk factors (e.g., health behaviors and occupational exposures). Objective: We examined proximal and distal drivers of cardiovascular disease and elucidated the interactions between modifiable and non-modifiable risk factors. Methods: We used a machine learning approach on four cohorts (2005-2012) of the National Health and Nutrition Examination Survey data to examine the effects of risk factors on cardiovascular risk quantified by the Framingham Risk Score (FRS) and the Pooled Cohort Equations (PCE). We estimated a network of risk factors, computed their strength centrality, closeness, and betweenness centrality, and computed a Bayesian network embodied in a directed acyclic graph. Results: In addition to traditional factors such as body mass index and physical activity, race and ethnicity and exposure to heavy metals are the most adjacent drivers of PCE. In addition to the factors directly affecting PCE, sleep complaints had an immediate adverse effect on FRS. Exposure to heavy metals is the link between race and ethnicity and FRS. Conclusion: Heavy metal exposures and race/ethnicity have similar proximal effects on cardiovascular disease risk as traditional clinical and lifestyle risk factors, such as physical activity and body mass. Our findings support the inclusion of diverse racial and ethnic groups in all cardiovascular research and the consideration of the social environment in clinical decision-making.

Impact of COVID-19 pandemic on the volume, cost, and outcomes of cardiac electrophysiology procedures in the United States.

BACKGROUND: During the COVID-19 pandemic, professional societies recommended deferral of elective procedures for optimal resource utilization. OBJECTIVE: We sought to assess changes in procedural trends and outcomes of electrophysiology (EP) procedures during the pandemic. METHODS: National Inpatient Sample databases were used to identify all EP procedures performed in the United States (2016-2020) by International Classification of Diseases, Tenth Revision codes. We evaluated trends in utilization, cost/revenue, and outcomes from EP procedures performed. RESULTS: An estimated 1.35 million EP procedures (82% devices and 18% catheter ablations) were performed (2016-2020) with significant yearly uptrend. During the pandemic, there was a substantial decline in EP procedure utilization from a 5-year peak of 298 cases/million population in the second quarter of 2019 to a nadir of 220 cases in the second quarter of 2020. In 2020, the pandemic was associated with the loss of 50,233 projected EP procedures (39,337 devices and 10,896 ablations) with subsequent revenue loss of $7.06 billion. This deficit was driven by revenue deficit from dual-chamber permanent pacemaker (PPM) utilization ($2.88 billion, 49.3% of lost cases), ablation procedures ($1.84 billion, 21.7% of lost cases), and implantable cardioverter-defibrillator implantation ($1.36 billion, 12.0% of lost cases). To the contrary, there was a 9.4% increase in the utilization of leadless PPM. EP device implantation during the pandemic was associated with higher adverse in-hospital events (9.4% vs 8.0%; P < .001). CONCLUSION: In the United States, the significant decline in EP procedures during the pandemic was primarily driven by the reduction in dual-chamber PPM utilization, followed by arrhythmia ablation and implantable cardioverter-defibrillator implantation. There was a substantial increase in leadless PPM utilization during the pandemic.

2023 HRS/APHRS/LAHRS guideline on cardiac physiologic pacing for the avoidance and mitigation of heart failure.

Cardiac physiologic pacing (CPP), encompassing cardiac resynchronization therapy (CRT) and conduction system pacing (CSP), has emerged as a pacing therapy strategy that may mitigate or prevent the development of heart failure (HF) in patients with ventricular dyssynchrony or pacing-induced cardiomyopathy. This clinical practice guideline is intended to provide guidance on indications for CRT for HF therapy and CPP in patients with pacemaker indications or HF, patient selection, pre-procedure evaluation and preparation, implant procedure management, follow-up evaluation and optimization of CPP response, and use in pediatric populations. Gaps in knowledge, pointing to new directions for future research, are also identified.

Efficacy and safety of dofetilide and sotalol in patients with hypertrophic cardiomyopathy.

BACKGROUND: Professional society practice guidelines conflict regarding their recommendations of dofetilide (DOF) and sotalol (STL) for treatment of arrhythmias in hypertrophic cardiomyopathy (HCM), and supporting data is sparse. We aim to assess safety and efficacy of DOF and STL on arrhythmias in HCM. METHODS: This was an observational study of HCM patients treated with DOF or STL for atrial fibrillation (AF) and ventricular arrhythmias (VA). Outcomes of drug discontinuation and arrhythmia recurrence were compared at 1 year and latest follow-up by Kaplan-Meier analysis. Predictors of drug failure were studied using uni- and multi-variable analyses. Drug-related adverse events were quantitated. RESULTS: Here we show that of our cohort of 72 patients (54 ± 14 years old, 75% male), 21 were prescribed DOF for AF, 52 STL for AF, and 18 STL for VA. At 1 year, discontinuation and recurrence rates were similar for DOF-AF (38% and 43%) and STL-AF (29% and 44%) groups. Efficacy data was similar at long-term follow-up of 1603 (IQR 994-4131) days, and for STL-VA. Drug inefficacy was the most common reason for discontinuation (28%) followed by side-effects (13%). Incidences of heart failure hospitalization (5%) and mortality (3%) were low. One STL-AF patient developed non-sustained torsades de pointes in the setting of severe pneumonia and acute kidney injury, but there were no other drug-related serious adverse events. CONCLUSIONS: DOF and STL demonstrate modest efficacy and satisfactory safety when used for AF and VA in HCM patients.

Hypertrophic cardiomyopathy (HCM) is a genetic condition that affects the heart muscle by making it abnormally thick. It often also causes abnormalities in the heartbeat, known as arrhythmias, which can cause symptoms such as dizziness and shortness of breath, or death. Historically it has been advised that some drugs that can affect the heartbeat should not be used in those with HCM, leaving people with HCM to be treated with other drugs that have undesirable side effects. We studied HCM patients who had been prescribed two of the drugs that were advised not to be used, called dofetilide and sotalol. The drugs were found to have been safe and effective over a 4-year period. These results suggest that clinical guidelines should be updated to support the use of these drugs for the treatment of arrhythmias in patients with HCM.

2023 HRS/APHRS/LAHRS guideline on cardiac physiologic pacing for the avoidance and mitigation of heart failure.

Cardiac physiologic pacing (CPP), encompassing cardiac resynchronization therapy (CRT) and conduction system pacing (CSP), has emerged as a pacing therapy strategy that may mitigate or prevent the development of heart failure (HF) in patients with ventricular dyssynchrony or pacing-induced cardiomyopathy. This clinical practice guideline is intended to provide guidance on indications for CRT for HF therapy and CPP in patients with pacemaker indications or HF, patient selection, pre-procedure evaluation and preparation, implant procedure management, follow-up evaluation and optimization of CPP response, and use in pediatric populations. Gaps in knowledge, pointing to new directions for future research, are also identified.

Sudden Cardiac Death in Patients With Type 1 Versus Type 2 Diabetes.

OBJECTIVE: To investigate the association between type 1 diabetes mellitus (T1D) and type 2 diabetes mellitus (T2D) with risk of sudden cardiac arrest (SCA). METHODS: In a prospective community-based study of SCA from February 1, 2002, through November 30, 2019, we ascertained 2771 cases age 18 years of age or older and matched them to 8313 controls based on geography, age, sex, and race/ethnicity. We used logistic regression to evaluate the independent association between diabetes, T1D, T2D, and SCA. RESULTS: Patients had a mean age of 64.5±15.9 years, were 33.3% female and 23.9% non-White race. Overall, 36.7% (n=1016) of cases and 23.8% (n=1981) of controls had diabetes. Among individuals with diabetes, the proportion of T1D was 6.5% (n=66) among cases and 2.0% among controls (n=40). Diabetes was associated with 1.5-times higher odds of SCA. Compared with those without diabetes, the odds ratio and 95% CI for SCA was 4.36 (95% CI, 2.81 to 6.75; P<.001) in T1D and 1.45 (95% CI, 1.30 to 1.63; P<.001) in T2D after multivariable adjustment. Among those with diabetes, the odds of having SCA were 2.41 times higher in T1D than in T2D (95% CI, 1.53 to 3.80; P<.001). Cases of SCA with T1D were more likely to have an unwitnessed arrest, less likely to receive resuscitation, and less likely to survive compared with those with T2D. CONCLUSION: Type 1 diabetes was more strongly associated with SCA compared with T2D and had less favorable outcomes following resuscitation. Diabetes type could influence the approach to risk stratification and prevention of SCA.

Sudden cardiac arrest in patients with schizophrenia: A population-based study of resuscitation outcomes and pre-existing cardiovascular disease.

Objective: Individuals with schizophrenia carry a high burden of cardiovascular disease and elevated rates of sudden cardiac arrest (SCA), but little published data is available regarding survival from SCA in this population. The authors compared cardiovascular disease burden and resuscitation outcomes following SCA in individuals with and without schizophrenia. Methods: Case-control analysis drawn from a prospective community-based study of SCA in a large community. The authors defined cases as having a pre-SCA history of schizophrenia, and controls as individuals with SCA without a history of schizophrenia. SCA cases with schizophrenia were compared to a 1:5 age- and sex-frequency-matched sample of SCA cases without schizophrenia. Results: The 103 SCA schizophrenia cases were as likely as the 515 cases without schizophrenia to have resuscitation attempted (75% vs. 80%; p = 0.24) and had a shorter 911 call mean response time (5.8 min vs. 6.9 min, p < 0.001). However, they were significantly less likely to present with a shockable rhythm (ventricular fibrillation/pulseless ventricular tachycardia 16% vs. 43%, p < 0.001), and less likely to survive to hospital discharge (3% vs. 14%, p = 0.008). Pre-arrest cardiovascular disease burden was similar in patients with and without schizophrenia. Conclusions: Despite comparable resuscitation characteristics and cardiovascular disease burden, patients with schizophrenia had significantly lower rates of SCA survival. The paucity of previous research into this phenomenon warrants further investigation to identify factors that may improve survival.

Adaptive Cardiac Resynchronization Therapy Effect on Electrical Dyssynchrony (aCRT-ELSYNC): A randomized controlled trial.

BACKGROUND: Adaptive cardiac resynchronization therapy (aCRT) is known to have clinical benefits over conventional CRT, but the mechanisms are unclear. OBJECTIVE: Compare effects of aCRT and conventional CRT on electrical dyssynchrony. METHODS: A prospective, double-blind, 1:1 parallel-group assignment randomized controlled trial in patients receiving CRT for routine clinical indications. Participants underwent cardiac computed tomography and 128-electrode body surface mapping. The primary outcome was change in electrical dyssynchrony measured on the epicardial surface using noninvasive electrocardiographic imaging before and 6 months post-CRT. Ventricular electrical uncoupling (VEU) was calculated as the difference between the mean left ventricular (LV) and right ventricular (RV) activation times. An electrical dyssynchrony index (EDI) was computed as the standard deviation of local epicardial activation times. RESULTS: We randomized 27 participants (aged 64 ± 12 years; 34% female; 53% ischemic cardiomyopathy; LV ejection fraction 28% ± 8%; QRS duration 155 ± 21 ms; typical left bundle branch block [LBBB] in 13%) to conventional CRT (n = 15) vs aCRT (n = 12). In atypical LBBB (n = 11; 41%) with S waves in V5-V6, conduction block occurred in the anterior RV, as opposed to the interventricular groove in strict LBBB. As compared to baseline, VEU reduced post-CRT in the aCRT (median reduction 18.9 [interquartile range 4.3-29.2 ms; P = .034]), but not in the conventional CRT (21.4 [-30.0 to 49.9 ms; P = .525]) group. There were no differences in the degree of change in VEU and EDI indices between treatment groups. CONCLUSION: The effect of aCRT and conventional CRT on electrical dyssynchrony is largely similar, but only aCRT harmoniously reduced interventricular dyssynchrony by reducing RV uncoupling.

Imaging-guided cardiac resynchronization therapy: A meta-analysis of randomized controlled trials.

BACKGROUND: Among patients with heart failure and left ventricular (LV) dysfunction despite guideline directed medical therapy, cardiac resynchronization (CRT) is an effective technology to reverse LV remodeling. Given that a large portion of patients are non-responders, alternatives to traditional LV-lead placement have been explored. A promising alternative is image targeted placement of an LV-lead to latest mechanically activated segment without scar. METHODS: Electronic database search for randomized controlled trials (RCTs) that evaluated the imaging-guided LV-lead placement on clinical, echocardiographic, and functional outcomes. The primary outcome was a composite of mortality and heart failure hospitalization. The secondary outcomes included CRT responders, New York Heart Association (NYHA), 6-minute walk test, Minnesota Living with Heart Failure Questionnaire (MLHFQ), and ejection fraction (EF) changes. RESULTS: Analysis included 4 RCTs of 691 patients with an average follow-up of 2 years (age 69.5 ± 10.3 years, 76% males, 54% ischemic cardiomyopathy, 81% with NYHA classes III/IV, and EF of 24.4% ± 8). The most common site for LV-lead paced segment was the anterolateral segment (45%) and at mid-LV (49%). Compared with the control, imaging-guided LV-lead placement was associated with a significant reduction of the primary outcome (hazard ratio [HR] = 0.60; 95% CI = 0.40-0.88; p = .01), higher CRT responders (odd ratio [OR] = 2.10; p < .01), more NYHA improvements by ≥1 (OR = 1.89; p = .01), increased 6MWT (mean difference [MD] = 25.78 feet; p < .01), and lower MLHFQ (MD = -4.04; p = .04), without significant differences in the LVEF (p = .08). CONCLUSIONS: In patients undergoing CRT, imaging-guided LV-lead placement was associated with improved clinical, echocardiographic, and functional status.

Cryoablation to improve catheter stability and ablation success in the right atrioventricular groove.

Catheter instability can limit ablation success of arrhythmia substrates at the right atrioventricular groove. We describe cases where cryoablation improved catheter stability, enabling ablation success. METHODS AND RESULTS: Four patients with supraventricular tachycardia (SVT) substrates at the right atrioventricular groove had radiofrequency ablation procedures limited by poor catheter contact. Cryoablation offered improved catheter stability, and all four patients achieved acute ablation success using cryoablation. Three patients had long-term success and one patient later required repeat radiofrequency ablation. CONCLUSIONS: For patients with arrhythmia substrates at the right atrioventricular groove, cryoablation may be a useful adjunctive technique in cases with catheter instability.

Sudden cardiac death during nighttime hours.

BACKGROUND: In the absence of apparent triggers, sudden cardiac death (SCD) during nighttime hours is a perplexing and devastating phenomenon. There are few published reports in the general population, with insufficient numbers to perform sex-specific analyses. Smaller studies of rare nocturnal SCD syndromes suggest a male predominance and implicate sleep-disordered breathing. OBJECTIVE: The purpose of this study was to identify mechanisms of nighttime SCD in the general population. METHODS: From the population-based Oregon Sudden Unexpected Death Study, we evaluated SCD cases that occurred in the community between 10 PM and 6 AM (nighttime) and compared them with daytime cases. Univariate comparisons were evaluated using Pearson χ2 tests and independent samples t tests. Logistic regression was used to further assess independent SCD risk. RESULTS: A total of 4126 SCD cases (66.2% male, 33.8% female) met criteria for analysis and 22.3% (n = 918) occurred during nighttime hours. Women were more likely to present with nighttime SCD than men (25.4% vs 20.6%; P < .001). In a multivariate regression model, female sex (odds ratio [OR] 1.3 [confidence interval (CI) 1.1-1.5]; P = .001), medications associated with somnolence/respiratory depression (OR 1.2 [CI 1.1-1.4]; P = .008) and chronic obstructive pulmonary disease/asthma (OR 1.4 [CI 1.1-1.6]; P < .001) were independently associated with nighttime SCD. Women were taking more central nervous system-affecting medications than men (1.9 ± 1.7 vs 1.4 ± 1.4; P = .001). CONCLUSION: In the general population, women were more likely than men to suffer SCD during nighttime hours and female sex was an independent predictor of nighttime events. Respiratory suppression is a concern, and caution is advisable when prescribing central nervous system-affecting medications to patients at an increased risk of SCD, especially women.