El Masry, Hicham

Background: Transthyretin (TTR) cardiac amyloidosis is a progressive cardiomyopathy with high mortality; however, the role of implantable cardioverter-defibrillators (ICDs) in this population remains unclear. Methods: This retrospective cohort study included patients with confirmed TTR cardiac amyloidosis, with or without ICDs, from January 1, 2001, to December 31, 2024, across all three Mayo Clinic sites (Arizona, Florida, and Minnesota). Diagnosis was confirmed by endomyocardial biopsy or abnormal technetium pyrophosphate (PYP) scintigraphy. A 1:4 propensity score-matched cohort of non-ischemic cardiomyopathy (NICM) patients with ICDs served as a control group. The primary outcome was all-cause mortality, comparing transthyretin cardiac amyloidosis (TTR-CA) patients by ICD status and against matched NICM patients. Secondary analyses evaluated predictors of mortality, including the use of tafamidis and the indication for ICD (primary vs. secondary prevention). Kaplan–Meier and Cox regression analyses were used to assess predictors of survival and mortality. Results: A total of 463 patients with confirmed TTR cardiac amyloidosis were included. The median follow-up duration was 7.4 years (interquartile range (IQR): 5.3–9.2 years) for the non-ICD group and 6.8 years (IQR: 4.5–9.0 years) for the ICD group. The median age was 74.5 years (IQR: 68.0–80.0 years), and 92.9% of patients were male. Among them, 206 (44.5%) received ICDs and 257 (55.5%) did not. ICD recipients were younger (71.0 vs. 77.0 years; p = 0.001) and had higher rates of hypertension (62.6% vs. 45.6%; p = 0.001), chronic kidney disease (CKD) (62.6% vs. 44.4%; p = 0.001), and diabetes (30.1% vs. 21.8%; p = 0.043). Median left ventricular ejection fraction was lower in the ICD groups (43% vs. 54%; p = 0.007), and N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels were higher in the ICD group (2259.0 pg/mL vs. 1503.0 pg/mL; p = 0.007). Among ICD recipients, 157 (76.2%) received the device for primary prevention, while 48 (23.3%) received the ICD for secondary prevention. Appropriate shocks were delivered in 22 patients (10.6%), primarily for ventricular tachycardia (n = 18) and ventricular fibrillation (n = 4). Inappropriate shocks occurred in six patients (3.0%), and 12 patients (5.8%) experienced device-related complications. Over 10 years of follow-up, ICD implantation did not confer a survival benefit for patients with TTR-CA compared to those without an ICD (p = 0.74). In contrast, a 1:4 propensity-matched NICM cohort with ICDs, which had a median follow-up of 7.1 years (IQR: 4.6–8.8 years), showed significantly improved survival than TTR-CA patients with ICDs (p = 0.034). Among the TTR-CA patients with ICDs, neither the use of tafamidis (p = 0.10) nor the ICD indication (primary vs. secondary prevention; p = 0.85) influenced mortality. In the Cox regression analysis, predictors of mortality in TTR-CA patients included older age (hazard ratio (HR) 1.048; p = 0.001), CKD (HR 1.637; p = 0.029), troponin T >50 ng/L (HR 1.594; p = 0.031), NT-proBNP >3000 pg/mL (HR 1.514; p = 0.050), and ejection fraction <40% (HR 1.935; p = 0.003). ICD implantation was not associated with improved survival (HR 0.932; p = 0.763). Conclusions: In conclusion, our data suggest that ICD therapy may not provide a significant overall survival benefit in older TTR-CA patients with impaired pump function; thus, prospective studies are warranted before any changes to clinical practice are considered. Key predictors of mortality included reduced ejection fraction and elevated cardiac biomarkers. Additional prospective studies are needed to clarify the role of ICDs in treatment strategies for patients with TTR-CA.

ABSTRACT Background Cardiac amyloidosis (CA) is frequently complicated by atrial fibrillation (AF), yet outcomes after left atrial appendage occlusion (LAAO) in this population remain poorly defined. Methods We conducted a retrospective TriNetX study of adults with AF undergoing LAAO, comparing patients with and without CA after 1:1 propensity matching. Outcomes were assessed using Kaplan–Meier analyses and Cox regression. Results Among 532 matched pairs, mortality and major adverse cardiovascular events were similar between groups, whereas major bleeding was higher in CA (HR 1.90). Conclusions LAAO yields comparable ischemic outcomes in CA, though bleeding risk is increased.

BACKGROUND: Cavotricuspid isthmus (CTI) ablation is frequently performed either as a standalone procedure or in combination with pulmonary vein isolation. With the rapid adoption of pulsed field ablation for atrial fibrillation, it is essential to delineate the utility of this modality in treating CTI-dependent atrial flutter (AFL). This study aims to evaluate the procedural and clinical outcomes of CTI ablation using pulsed field energy. METHODS: We conducted a retrospective analysis of consecutive patients who underwent pulsed field ablation for CTI-dependent AFL between January 2024 and March 2025. The primary end points were acute procedural success, periprocedural complications, and CTI-dependent AFL recurrence during follow-up. RESULTS: A total of 132 patients underwent CTI nonthermal ablation. The median age was 69.5 years, and 27.3% were female. The Farawave catheter was used in 93.9% of cases, PulseSelect in 4.5%, and Sphere-9 in 1.5%. Acute block was achieved in 99.2% of patients, although 8 required adjunctive radiofrequency ablation to complete the line. Periprocedural complications included transient ST-segment elevation in 2 patients and transient conduction disturbances in 3. During a median follow-up of 114 days (n=131), 5 patients (3.8%) experienced recurrence of typical AFL. The 6-month typical AFL-free survival estimate was 93.6%. CONCLUSIONS: Pulsed field ablation appears to be a feasible and effective strategy for CTI-dependent AFL. However, anatomic variability may limit its universal applicability with current catheter designs. Although acute procedural success is high, the long-term durability of the CTI block and its comparative efficacy versus conventional thermal ablation remain areas requiring further investigation.

ABSTRACT Introduction Cardiac resynchronization therapy (CRT) improves clinical outcomes in patients with heart failure with reduced ejection fraction (HFrEF). However, data on its efficacy in patients with sarcoidosis and HFrEF are limited. Methods Using the TriNetX network, we identified patients with sarcoidosis, heart failure with a left ventricular ejection fraction (LVEF) below 35%, and either left bundle branch block (LBBB) or prolonged QRS duration ( > 150 ms) between 2014 and 2019. Patients were categorized into two cohorts: (1) those who received CRT and (2) those who received an ICD‐only implant. Five‐year outcomes included all‐cause mortality, all‐cause hospitalization, heart failure exacerbation, and the proportion of patients with improvement in LVEF to greater than 40% and greater than 50%. Results Out of 245 eligible patients, we identified a cohort of 87 patients (mean age 62.6 ± 9.5 years) who received CRT and 87 patients (mean age 62.1 ± 11.1 years) who received ICD‐only implant, with similar propensity scores, and included them in a comparative analysis. At 5‐year follow‐up, the CRT group demonstrated outcomes comparable to the ICD‐only implant group for all‐cause mortality (14.9% vs. 20.7%; HR 0.63; 95% CI 0.31–1.28; p = 0.19), all‐cause hospitalization (83.9% vs. 77.0%; HR 1.24; 95% CI 0.89–1.73; p = 0.19), and heart failure exacerbation (28.7% vs. 28.7%; HR 0.90; 95% CI 0.52–1.57; p = 0.72). The proportion of patients with improvement in LVEF to greater than 40% and greater than 50% was also similar in both groups (LVEF > 40%, 43.7% vs. 33.3%; HR 1.30; 95% CI 0.80–2.10; p = 0.29; LVEF > 50%, 31.0% vs. 17.2%; HR 1.72; 95% CI 0.92–3.24; p = 0.09). Conclusion CRT implantation had similar long‐term outcomes compared to ICD‐only implantation in patients with sarcoidosis and HFrEF, particularly all‐cause mortality, all‐cause hospitalization, heart failure exacerbation, and the proportion of patients with improvement in LVEF to greater than 40% and greater than 50%.

ABSTRACTBackgroundThe factors contributing to sustained ventricular arrhythmias (VAs) >30 days after left ventricular assist device (LVAD) implantation are not well‐established.ObjectivesThis study aimed to predict the factors associated with late sustained VAs after LVAD implantation and develop a predictive score to identify patients with an increased risk of late sustained VAs after the procedure.MethodsWe performed a retrospective cohort study on a training cohort of 623 patients and a validation cohort of 157 patients who underwent LVAD implantation at the Mayo Clinic (Rochester, Phoenix, and Jacksonville) from January 1, 2000, to December 30, 2020. Late sustained VAs were defined as ventricular tachycardia (VT) and ventricular fibrillation (VF) occurring >30 days after the LVAD procedure. Detailed chart reviews of the electronic health records within the Mayo Clinic and outside medical records were performed.ResultsA total of 780 patients were included in our study. Late sustained VAs occurred in 30% (n = 232) of the patients. The significant factors associated with late sustained VAs after LVAD were the history of VAs prior to LVAD (34.1% vs. 23.0%, p < 0.01), implantable cardiac defibrillator (ICD) (87.9% vs. 77.6%, p < 0.01) or cardiac resynchronization therapy (CRT) in situ (43.5% vs. 33.6%, p = 0.008), VT ablation prior to LVAD (5.2% vs. 1.8%, p = 0.010), use of amiodarone (49.1% vs. 38.7%, p = 0.007), use of mexiletine (15.5% vs. 5.7%, p < 0.01), and higher left ventricular end‐diastolic diameter (LVEDD) on echocardiography prior to LVAD implantation (71.4 vs. 68.7 mm, p = 0.002). During follow‐up, the patients who developed late sustained VAs after LVAD had lower survival than those who did not (HR = 1.96, 95% CI:156–2.4, p < 0.001). The average time from LVAD to orthotopic heart transplant was longer among late sustained VAs patients (23 vs. 14 months, p < 0.01). The “VIN” risk score was created to identify four risk groups: low (scores 0), intermediate (score 1), high (score 2), and very high (score 3). The rates of late VA's in the training cohort at 1 year were 9.5%, 14%, 18%, and 25% which was almost similar to the risk of late VA's at validation cohort 10%, 12%, 20%, and 63%, respectively.ConclusionsLate sustained VAs occurred in 30% of the patients who received LVAD and were associated with lower survival. The VIN risk score was developed and validated to stratify patients into low, intermediate, high, and very high risk of late sustained VAs.

Abstract Aims Atrial fibrillation (AF) is the most common cardiac arrhythmia. Although lipoprotein(a) [Lp(a)] is known to be a well-established risk factor for atherosclerotic cardiovascular disease, its role in the development of AF, independent of this association, remains unclear. Methods and results Adult patients from the three Mayo Clinic sites with a baseline Lp(a) and without AF history were included. Patients were categorized into two groups based on their Lp(a) levels: high Lp(a) (≥50 mg/dL) and low Lp(a) (&lt;50 mg/dL). Survival probabilities free from incident AF were compared between Lp(a) groups, during a follow-up period up to 15 years, using the Kaplan–Meier curve and the log-rank test. Multivariable Cox regression analysis was also conducted. A total of 75 376 patients were included (median age: 55 years, 59% males), with a median follow-up duration of 8.8 (inter-quartile range: 3.4, 14.8) years. Incident AF was detected in 5738 (7.6%) patients. Survival probability free from incident AF was significantly lower in patients with elevated Lp(a) (86%) compared with those with low Lp(a) (88%, log-rank P &lt; 0.001). Multivariable analysis adjusted for potential risk factors of AF showed a statistically significant association of elevated Lp(a) with an 11% increase in AF risk (adjusted hazard ratio: 1.11, 95% confidence interval: 1.05–1.18). Conclusion Our study suggests that elevated Lp(a) (≥50 mg/dL) is an independent risk factor for incident AF. Future prospective studies are warranted to validate our results and to test if reducing Lp(a) could mitigate the burden of AF.

Despite advances in ablative therapies, outcomes remain less favorable for persistent atrial fibrillation often due to presence of non-pulmonary vein triggers and abnormal atrial substrates. This review highlights advances in ablation technologies and notable scientific literature on clinical outcomes associated with pursuing adjunctive ablation targets and substrate modification during persistent atrial fibrillation ablation, while also highlighting notable future directions.

Cardiac sarcoidosis (CS) is characterized by various arrhythmic manifestations ranging from catastrophic sudden cardiac death secondary to ventricular arrhythmia, severe conduction disease, sinus node dysfunction, and atrial fibrillation. The management of CS is complex and includes not only addressing the arrhythmia but also controlling the myocardial inflammation resultant from the autoimmune reaction. Arrhythmic manifestations of CS carry significant prognostic implications and invariably affect long-term survival in these patients. In this review, we focus on management of arrhythmic manifestation of cardiac sarcoidosis as well as risk stratification for sudden cardiac death in these patients.