Citations

Background: Early catheter ablation for atrial fibrillation (AF) improves outcomes, but the optimal timing, especially in heart failure (HF) subtypes, remains unclear. Objective: To evaluate the impact of ablation timing on outcomes in patients with HF with reduced ejection fraction (HFrEF) and HF with preserved ejection fraction (HFpEF). Methods: We used the TriNetX database (2010–2024) to identify HF patients with AF who underwent ablation. Patients were classified as early ablation (≤1 year of first AF diagnosis) or delayed ablation (1–3 years), with propensity score matching (PSM) applied to balance the baseline characteristics. The primary outcome was AF recurrence, defined by repeat ablation, direct current cardioversion (DCCV), or antiarrhythmic drug (AAD) use after a 3-month blanking period. Secondary outcomes included stroke, hospitalization, and mortality over 5 years. Results: After PSM, delayed ablation was associated with higher AF recurrence in both HFrEF (HR 1.25, p < 0.001) and HFpEF (HR 1.27, p = 0.01), as seen in multivariate analysis. In HFrEF, delayed ablation was associated with higher incidence of re-do ablation, AAD use, and DCCV, while in HFpEF, higher recurrence with delayed ablation was associated with increased AAD use. Both cohorts had similar stroke and mortality rates between early and delayed ablation. Conclusions: Delayed ablation in HFrEF and HFpEF was linked to higher AF recurrence, driven by increased redo ablations, DCCV, AAD use in HFrEF, and higher AAD use in HFpEF. Stroke and mortality rates were similar, suggesting earlier ablation may enhance rhythm control without affecting long-term survival.

Background: Dofetilide, a commonly prescribed class III antiarrhythmic for atrial fibrillation (AF), currently requires a 3-month amiodarone washout period per FDA guidelines. We evaluated the safety of initiating dofetilide within this 3-month washout period. Methods: We performed a retrospective cohort study across all Mayo Clinic sites and identified patients using centralized datamart that were transitioned from amiodarone to dofetilide in less than 90 days. Patients were included and confirmed by manual chart review if they had been on amiodarone for ≥ 12 weeks and if available amiodarone level >0.3 mg/ml at the time of dofetilide initiation. Serial ECGs were assessed during the hospitalization for dofetilide initiation and at 3-, 6-, and 12-months follow-up to evaluate QT interval. Primary safety end point was torsade de pointes. Results: The final cohort included 66 patients with a mean age of 65 ±14 years; 71.0% were male; and the average BMI was 29.6 ±5.1 kg/m 2 . Of the 66 patients, 65 had a history of AF: 31.8% paroxysmal, 54.5% persistent, and 12.1% long-standing persistent. Permanent pacemakers and ICDs were present in 27.3% and 22.7% of patients. Patients received amiodarone for a median of 7.8 months at a mean daily dose of 187.1±48.3 mg (range: 100 – 400 mg), with a mean transition period of 44.2±20.3 days. Of 66 patients, 16 (24 %) transitioned within 30 days of stopping amiodarone—including 5 (8 %) within 14 days—while the remaining 50 (76 %) was between 30 and 90 days. A total of 24.2% (16/66) patients required dofetilide dose reduction due to QT prolongation and 10.6% of patients (7/66) required drug discontinuation. There was no difference in either discontinuation rate or dose reduction rate in patients with a transition period ≤30 days vs > 30 days [6.25% vs. 12% (p=0.85) and 12.5% vs. 28% (p=0.36), respectively]. No cases of torsades de pointes were observed during dofetilide initiation or follow up. Conclusion: In this cohort, dofetilide initiation less than 90 days after amiodarone discontinuation was not associated with increased torsades de pointes risk. These data challenge and support reconsideration of the blanket 3-month washout and suggest that a monitored, expedited rhythm-control transition is feasible and safe.

ABSTRACT Background Recent data show increased ventricular tachycardia (VT) related mortality. We aimed to investigate the trends and disparities of VT‐related mortality according to cardiomyopathy subtypes. Methods Mortality and demographic data were obtained from the CDC Wide‐ranging Online Data for Epidemiologic Research database between 1999 and 2020. VT‐related mortality was defined as the underlying cause of death and ischemic cardiomyopathy (ICM) or nonischemic cardiomyopathy (NICM) as the contributing cause of death. The direct method of standardization was utilized to estimate age‐adjusted mortality rates (AAMRs). Temporal trends were evaluated using log‐linear regression models. Results A total of 15 888 deaths were related to both VT and ICM, and 16 777 were due to both VT and NICM. There was a significant increase in VT and ICM‐related mortality between 2006 and 2020 with an APC of +1.38% ( p < 0.05). Similarly, VT and NICM‐related mortality increased between 2008 and 2020 with an APC of +0.60% ( p < 0.05). ICM had a higher AAMR in males [6.23 (6.12–6.34)], Whites [3.49 (3.43–3.54)], Hispanics [2.11 (1.95–2.26)], and the Midwest region [3.73 (3.61–3.85)] compared to NICM. In contrast, NICM had a higher AAMR in females [1.57 (1.52–1.61)], Black or African Americans [5.02 (4.84–5.20)], and the South region [3.10 (3.03–3.18)]. p for all trend < 0.05. Conclusions Real‐world data show significant differences in VT‐related mortality according to cardiomyopathy subtypes with prominent sex, race, and regional disparities. Clinical and public health strategies are needed to address inequities and improve outcomes.

ABSTRACT Background Ventricular tachycardia (VT) is a major contributor to sudden cardiac death among patients with ischemic heart disease (IHD). While catheter ablation reduces the arrhythmic burden, the impact on long‐term outcomes remains uncertain. We assess the efficacy of catheter ablation in patients with IHD. Methods We performed a meta‐analysis by systematically searching electronic databases from inception to April 2025. Pairwise, reconstructed time‐to‐event data meta‐analyses and Trial Sequential analyses were conducted. Results A total of seven studies (1192 participants) were included. Among patients with IHD with ICD, VT ablation was associated with a significant reduction in ICD shocks (RR = 0.50, 95% CI = [0.34–0.74]), a trend toward reduced VT storm (RR = 0.64, 95% CI = [0.40–1.04], p = 0.07), and lower rates of cardiovascular hospitalization (RR = 0.73, 95% CI = [0.53–1.01], p = 0.06) compared to ICD alone. However, no significant differences were observed when compared to patients receiving ICD plus antiarrhythmic drugs (AADs). VT ablation showed no significant impact on mortality or VT/VF recurrence compared to either ICD alone or ICD with AADs. Reconstructed Kaplan–Meier analysis for all‐cause mortality showed no significant difference between VT ablation and AAD + ICD. Trial Sequential Analysis provided conclusive evidence for VT/VF recurrence, while further data is required for other outcomes. Conclusion Among patients with IHD with ICD, VT ablation reduces ICD shocks, VT storm, and cardiovascular hospitalizations compared to ICD‐only therapy, but offers no significant advantage over ICD combined with AADs. VT ablation does not impact overall mortality or the recurrence of VT/VF. Trial sequential analysis confirmed conclusive evidence for VT/VF recurrence, while additional data is needed for other outcomes.

Importance Sleep disordered breathing (SDB) is a well-established contributor to cardiovascular morbidity, mediated by intermittent hypoxemia, autonomic dysregulation, and endothelial dysfunction. Patients with hypertrophic cardiomyopathy (HCM) may be especially at risk for SDB, but the clinical impact of SDB in this population remains unclear. Objective To define the prevalence and subtypes of SDB in HCM and examine their association with echocardiographic parameters and cardiac biomarker expression. Design, Setting, and Participants A prospective cohort study was conducted between April 18, 2018, and January 15, 2024, at a single tertiary referral center specializing in HCM care. Adults with HCM (left ventricular wall thickness ≥15 mm or pathogenic variants) were recruited from an institutional registry. Patients diagnosed with SDB or current pregnancy were excluded. Patients underwent polysomnography, with comparative assessment of echocardiographic, electrocardiographic, and biomarker indices. Observers were blinded to polysomnographic results. Data analysis was performed from April 11, 2024, to July 25, 2024. Exposures SDB classified via polysomnography using apnea-hypopnea index thresholds, with subtypes including obstructive sleep apnea and central sleep apnea and with event severity, hypoxemia, and sleep architecture disruption quantified. Main Outcomes and Measures Echocardiographic indices, cardiac biomarker expression, functional status, apnea-hypopnea index, and overnight hypoxemia. Results Among 154 patients (median [IQR] age, 60 [48-68] years; 102 [66.2%] male), 91 (59.1%) were diagnosed with SDB. Those with SDB, compared with those without SDB, had higher left ventricular mass index (median [IQR], 128 [107-161] vs 109 [96-134] g/m 2 ; P = .03), E/e′ ratio (median [IQR], 12.5 [10.0-15.0] vs 10.0 [8.3-14.5]; P = .04), and baseline troponin-T level (median [IQR], 0.013 [0.009-0.022] vs 0.011 [0.007-0.015] ng/mL [to convert to micrograms per liter, multiply by 1]; P = .04) and greater overnight troponin-T level increases (change in median [IQR], 0.0021 [−0.0029 to 0.0062] vs 0.0002 [−0.0022 to 0.0026] ng/mL; P = .02). New York Heart Association class II or III symptoms were more common in those with SDB (48 [52.7%] vs 17 [27.0%]; P = .005). Hypertension and diabetes were more prevalent among patients with SDB than without SDB (hypertension: 67 [73.6%] vs 36 [57.1%]; P = .03; diabetes: 14 [15.4%] vs 3 [4.8%]; P = .04), whereas rates of atrial fibrillation and prior myectomy did not differ significantly between groups. Conclusions and Relevance This study suggests that undiagnosed SDB is highly prevalent in patients with HCM and that SDB is associated with adverse myocardial remodeling, greater diastolic dysfunction, and elevated troponin-T levels, indicating subclinical myocardial injury. SDB may contribute to HCM pathophysiology and symptom burden, supporting the rationale for randomized clinical trials to determine the impact of treating SDB on symptoms and clinical outcomes in patients with HCM.

Background: Ventricular tachycardia (VT) is a life-threatening arrhythmia frequently observed in structural heart diseases, including LMNA-related cardiomyopathy, a genetic disorder associated with high risk of sudden cardiac death and progressive systolic dysfunction. While catheter ablation is an established therapeutic option for VT, its efficacy in cardiac laminopathy remains poorly defined. Objectives: To synthesize available evidence on the role and outcomes of VT ablation in patients with cardiac laminopathy. Methods: A systematic review and single-arm meta-analysis was performed in accordance with PRISMA guidelines. PubMed, Embase, and Cochrane databases were searched for studies reporting VT ablation outcomes in LMNA-related cardiomyopathy. An inverse variance random-effects model was applied for meta-analysis of proportions. Results: Seven studies (six cohorts, one abstract) comprising 62 patients (mean age 53.2 ± 9.7 years; 85% male; 88% with implantable cardioverter-defibrillator) were included. An endocardial/endo-epicardial approach was used in 93% of cases. Acute procedural success was achieved in 37% (95% CI: 14–63%; I 2 = 27.4%), and 28% required multiple procedures. Over a median follow-up of 26 (9–35) months, VT recurrence occurred in 91% (95% CI: 76–100%; I 2 = 37.2%). All-cause mortality was 54% (95% CI: 39–70%; I 2 = 28%), predominantly from cardiac causes (51%, 95% CI: 25–76%; I 2 = 53%), and 14% (95% CI: 1–34%; I 2 = 42%) underwent heart transplantation. Conclusions: In LMNA-related cardiomyopathy, catheter ablation is associated with high VT recurrence, limited long-term success, and substantial cardiovascular mortality and transplantation rates, underscoring the importance of ICD implantation and the need for alternative strategies, including variant-specific and molecularly targeted therapies.

Background Disease‐causative variants in LMNA ‐encoded lamin A/C cause a genetic cardiomyopathy characterized by atrioventricular block, atrial fibrillation, ventricular arrhythmias, and systolic dysfunction. The influence of LMNA variant type/localization on late gadolinium enhancement (LGE) patterns and clinical outcomes remains unclear. Methods Retrospective analysis of 822 genotype‐positive patients with arrhythmogenic/dilated cardiomyopathy was used to identify those with disease‐causative variants in LMNA . Data on LGE distribution and prevalence of advanced heart failure, thromboembolic and sudden cardiac death/major ventricular arrhythmia events were extracted from the electronic record and analyzed by variant type/localization. Results Among the 72/116 (62%) LMNA variant‐positive patients with cardiac magnetic resonance imaging data, LGE was observed in 40/72 (56%) cases. Most exhibited a nonischemic, midmyocardial or subepicardial pattern (73%), and 6/40 (15%) showed a unique “pseudo‐infarct” transmural pattern, predominantly affecting the apical segments. All 6 patients with this distinct LGE pattern harbored C‐terminal IgD (immunoglobulin‐like domain) variants (p.Arg471His or p.Arg541His). In patients with clinically manifest disease (76/116), those with IgD‐localizing variants had a lower prevalence of atrioventricular block (25% versus 72%, P =0.002) and atrial fibrillation (50% versus 81%, P =0.019) but higher rates of thromboembolic events (42% versus 16%, P =0.038). During a median follow‐up of 37 months, IgD variant presence independently predicted sudden cardiac death/major ventricular arrhythmia (hazard ratio, 2.391 [95% CI, 1.046–5.464]; P =0.039). Conclusions LMNA missense variants localizing to IgD present a distinct apical pseudo‐infarct LGE pattern associated with increased risk of ventricular arrhythmias and thromboembolic events but reduced atrioventricular block and atrial fibrillation. Multicenter studies are warranted to develop variant‐specific risk‐stratification strategies in cardiac laminopathy.

ABSTRACTIntroductionIntramyocardial needle ablation is a novel technique for treating refractory ventricular tachycardia (VT) and premature ventricular complexes (PVC). However, studies defining the effectiveness and safety of this procedure are limited. This meta‐analysis aims to evaluate the safety and effectiveness of needle ablation for VT and PVC refractory to standard ablation.MethodsEmbase, Ovid (includes Medline), and ClinicalTrials.gov were searched from inception to December 31, 2024. Human studies on needle ablation for recurrent VT and PVC were included. Primary outcome was immediate effectiveness (no immediate post‐procedural inducible VT or PVC). Secondary outcomes were long‐term effectiveness (no clinical VT or PVC at 6 months) and safety (composite measure of peri‐ and post‐procedural complications).ResultsA total of five studies including 180 patients (140 VT; 40 PVC) were analyzed. Mean ages ranged from 54 to 66 years. Among 129 patients with VT, immediate effectiveness was 75% (95% CI, 54–92; I2 80%), and cumulative freedom from clinical VT dropped to 43% at 6 months (95% CI, 35–52; I2 0%). Among 40 patients with PVC, immediate effectiveness was 82% (95% CI, 67–94; I2 0%), and long‐term effectiveness was 76% (95% CI, 61–90; I2 0%). Safety outcomes were reported in 19% of patients (95% CI, 13–27; I2 0%) and 10% of patients (95% CI 1, 23; I2 0%) in the VT and PVC arm, respectively. Death related to ablation was report in 7 patients (5.0%) only in the VT studies.ConclusionIntramyocardial needle ablation is an emerging alternative approach for refractory VT and PVC ablation, showing cautious but promising results and safety profiles. Prospective studies and an international registry could provide valuable insights needed for optimal patient selection and protocol refinement.