Association of pre-left ventricular assist device defibrillator shocks for ventricular arrhythmia with clinical outcomes after left ventricular assist device implantation.

Background: Implantable cardioverter-defibrillation (ICD) shocks after left ventricular assist device therapy (LVAD) are associated with adverse clinical outcomes. Little is known about the association of pre-LVAD ICD shocks on post-LVAD clinical outcomes and whether LVAD therapy affects the prevalence of ICD shocks. Objectives: The purpose of this study was to determine whether pre-LVAD ICD shocks are associated with adverse clinical outcomes post-LVAD and to compare the prevalence of ICD shocks before and after LVAD therapy. Methods: Patients 18 years or older with continuous-flow LVADs and ICDs were retrospectively identified within the University of Pittsburgh Medical Center system from 2006-2020. We analyzed the association between appropriate ICD shocks within 1 year pre-LVAD with a primary composite outcome of death, stroke, and pump thrombosis and secondary outcomes of post-LVAD ICD shocks and ICD shock hospitalizations. Results: Among 309 individuals, average age was 57 ± 12 years, 87% were male, 80% had ischemic cardiomyopathy, and 42% were bridge to transplantation. Seventy-one patients (23%) experienced pre-LVAD shocks, and 69 (22%) experienced post-LVAD shocks. The overall prevalence of shocks pre-LVAD and post-LVAD were not different. Pre-LVAD ICD shocks were not associated with the composite outcome. Pre-LVAD ICD shocks were found to predict post-LVAD shocks (hazard ratio [HR] 5.7; 95% confidence interval [CI] 3.42-9.48; P <.0001) and hospitalizations related to ICD shocks from ventricular arrhythmia (HR 10.34; 95% CI 4.1-25.7; P <.0001). Conclusion: Pre-LVAD ICD shocks predicted post-LVAD ICD shocks and hospitalizations but were not associated with the composite outcome of death, pump thrombosis, or stroke at 1 year. The prevalence of appropriate ICD shocks was similar before and after LVAD implantation in the entire cohort.

Cardiovascular Hospitalizations and Resource Use Following Atrial Fibrillation Ablation.

Background Over the next few years, atrial fibrillation (AF)-related morbidity and costs will increase significantly. Thus, it is prudent to examine the impact of AF treatment on health care resource use. This study examined the impact of AF ablation on hospitalization, length of stay, and resource use for patients undergoing AF ablation in a multihospital system. Methods and Results In an observational analysis, outcomes of total, cardiovascular, and AF hospitalizations, emergency department visits, and length of stay were compared for 3417 patients between 12 months before and 24 months following AF ablation. Use of electrical cardioversions and antiarrhythmic use were also compared 1 year before to 2 years after AF ablation. There were fewer total (0.7±1.3 versus 0.3±0.7; P<0.001), cardiovascular (0.7±1.2 versus 0.2±0.6; P<0.001), and AF (0.6±1.1 versus 0.1±0.3; P<0.001) hospitalizations and emergency department visits (0.8±2.1 versus 0.4±0.9; P<0.001) per patient-year for the 2 years following AF ablation compared with 1 year before. Average length of stay per patient-year (1.4±7.9 versus 3.6±5.3 days; P<0.0001), the percentage of patients on antiarrhythmic therapy (21.2% versus 58.5%; P<0.0001), and those undergoing electrical cardioversions (16.1% versus 28.1%; P<0.0001) were lower 2 years following AF ablation versus 1 year before. Conclusions We noted a decrease in total, cardiovascular, and AF hospitalizations and health care resource use during the 2-year period after index AF ablation, compared with the 1 year before. AF ablation may portend a decline in patient morbidity and health care costs.

Guideline-Directed Medical Therapy and the Risk of Death in Primary Prevention Defibrillator Recipients.

BACKGROUND: Contemporary guideline-directed medical therapy (GDMT) confers a significant mortality benefit for patients with heart failure with reduced ejection fraction (HFrEF), as compared to GDMT prevalent at the time of landmark primary prevention implantable cardioverter-defibrillator (ICD) trials. The impact of modern era GDMT on survival in this population is unknown. OBJECTIVES: This study sought to investigate the impact of number of GDMT medications prescribed for HFrEF on all-cause mortality in recipients of primary prevention ICD. METHODS: A cohort of 4,972 recipients with primary prevention ICD (n = 3,210) or cardiac resynchronization therapy-defibrillator (CRT-D) (n = 1,762) was studied. The association of number of GDMT medications prescribed at the time of device implantation and all-cause mortality at 2 years post implantation was examined. RESULTS: In our primary prevention cohort, 5%, 20%, 52%, and 23% of patients were prescribed 0, 1, 2, or 3-4 GDMT medications, respectively. After risk adjustment for age, sex, ejection fraction, body mass index, the Elixhauser comorbidity score, the type of cardiomyopathy, and the year of device implantation, each additional GDMT conferred a reduction in the risk of death of 36% in recipients of ICD (HR: 0.64; P < 0.001) and 30% in recipients of CRT-D (HR: 0.70; P < 0.001). CONCLUSIONS: A higher number of prescribed GDMT medications is associated with an incremental 1-year survival in recipients of primary prevention ICD with or without CRT. Initiation of maximum number of tolerated GDMT medications should therefore be the goal for all patients with HFrEF. In the setting of robust GDMT, the risk versus benefit of a primary prevention ICD warrants re-examination in future studies.

Cardiac resynchronization therapy using a pacemaker or a defibrillator: Patient selection and evidence to support it.

Cardiac resynchronization therapy (CRT) is an established treatment for patients with heart failure (HF), myocardial dysfunction and prolonged ventricular depolarization on surface electrocardiogram. CRT can be delivered by a pacemaker (CRT-P) or a combined pacemaker-defibrillator (CRT-D). Although these two types of devices are very different in size, function, and cost, current published guidelines do not distinguish between them, leaving the choice of which device to implant to the treating physician and the informed patient. In this paper, we review the published CRT clinical trial literature with focus on the outcomes of HF patients treated with CRT-P versus CRT-D. We also attempt to provide guidance as to the appropriate choice of CRT device type, in the absence of randomized prospective trials geared to answer this specific question.

Increased Mortality in Patients With Preoperative and Persistent Postoperative Pulmonary Hypertension Undergoing Mitral Valve Surgery for Mitral Regurgitation: A Cohort Study.

Background Preoperative pulmonary hypertension (PH) is associated with excess mortality among patients with severe mitral regurgitation undergoing mitral valve surgery (MVS). However, the links between PH phenotype, pulmonary vascular remodeling, and persistent postoperative PH are not well understood. We aimed to describe the associations between components of pulmonary hemodynamics as well as postoperative residual PH with longitudinal mortality in patients with severe mitral regurgitation who received MVS. Methods and Results Patients undergoing MVS for severe mitral regurgitation from 2011 to 2016 were retrospectively identified within our health system (n=488). Mean pulmonary artery pressure and other hemodynamic variables were determined by presurgical right-heart catheterization. Postoperative pulmonary artery systolic pressure was assessed on echocardiogram 42 to 365 days post-MVS. Longitudinal survival over a mean 3.9 years of follow-up was evaluated using Cox proportional hazards modeling to compare survival after adjustment for demographics, surgical characteristics, and comorbidities. Pre-MVS prevalence of PH was high at 85%. After adjustment, each 10-mm Hg increase in preoperative mean pulmonary artery pressure was associated with a 1.38-fold increase in risk of death (95% CI, 1.13-1.68). Elevated preoperative pulmonary vascular resistance, transpulmonary gradient, and right atrial pressure were similarly associated with increased mortality. Among 231 patients with postoperative echocardiogram, evidence of PH on echocardiogram (pulmonary artery systolic pressure ≥35 mm Hg) was associated with increased risk of death (hazard ratio [HR], 2.02 [95% CI, 1.17-3.47]); however, this was no longer statistically significant after adjustment (HR, 1.55 [95% CI, 0.85-2.85]). Conclusions In patients undergoing MVS for mitral regurgitation, preoperative PH, and postoperative PH were associated with increased mortality.

Association between cumulative social risk, particulate matter environmental pollutant exposure, and cardiovascular disease risk.

BACKGROUND: Long-term exposure to pollution has been shown to increase risk of cardiovascular disease (CVD) and mortality, and may contribute to the increased risk of CVD among individuals with higher social risk. METHODS: Data from the community-based Heart Strategies Concentrating on Risk Evaluation (HeartSCORE) study were used to quantify Cumulative Social Risk (CSR) by assigning a score of 1 for the presence of each of 4 social risk factors: racial minority, single living, low income, and low educational status. 1-year average air pollution exposure to PM2.5 was estimated using land-use regression models. Associations with clinical outcomes were assessed using Cox models, adjusting for traditional CVD risk factors. The primary clinical outcome was combined all-cause mortality and nonfatal CVD events. RESULTS: Data were available on 1933 participants (mean age 59 years, 66% female, 44% Black). In a median follow up time of 8.3 years, 137 primary clinical outcome events occurred. PM2.5 exposure increased with higher CSR score. PM2.5 was independently associated with clinical outcome (adjusted hazard ratio [HR]: 1.19 [95% CI: 1.00, 1.41]). Participants with ≥2 CSR factors had an adjusted HR of 2.34 (1.48-3.68) compared to those with CSR = 0. The association was attenuated after accounting for PM2.5 (HR: 2.16; [1.34, 3.49]). Mediation analyses indicate that PM2.5 explained 13% of the risk of clinical outcome in individuals with CSR score ≥ 2. CONCLUSION: In a community-based cohort study, we found that the association of increasing CSR with higher CVD and mortality risks is partially accounted for by exposure to PM2.5 environmental pollutants.