Citations

ABSTRACT Background Mitral annular disjunction (MAD) carries an increased risk of complex ventricular arrhythmias, which can lead to sudden cardiac death. Many of these patients undergo implantable cardioverter defibrillator (ICD) implantation, but their ICD outcomes are not known. Objective The aim of this study was to assess the outcomes of ICD implantation and the predictors of appropriate ICD therapies in patients with MAD. Methods The study included patients with MAD who underwent ICD implantation. Clinical, electrocardiographic, cardiac imaging, and device therapy data were collected. Results Forty‐nine patients with MAD and ICD were included. Median age was 49 (21) years, and 29 (59%) were female. 13 (27%) patients underwent ICD implantation for primary prevention and 36 (73%) patients for secondary prevention. Over a median follow‐up of 27.3 (35.3) months, 23 (47%) patients received ICD therapies. 18 (37%) patients had appropriate ICD therapies, and 5 (10%) patients had inappropriate ICD shocks. Median time to first appropriate therapy was 22.3 (63.3) months. In patients with a secondary prevention ICD indication, the rate of appropriate ICD therapies was 44%, while in patients with a primary prevention ICD indication, it was 15%. Among patients with appropriate ICD therapies, the first therapies were delivered for monomorphic ventricular tachycardia (VT) in 7 (39%) patients and polymorphic VT or ventricular fibrillation (VF) in 11 (61%) patients. Patients with appropriate ICD therapies were more likely to have a history of SCA ( p = 0.003) and/or low left ventricular ejection fraction (LVEF) ( p = 0.022) before ICD implantation as compared to patients without appropriate ICD therapies. Conclusions In our cohort of patients with MAD and ICD, appropriate ICD therapies were common. Most appropriate ICD therapies were delivered for polymorphic VT or VF. Larger studies are needed to elucidate the mechanisms of VAs and refine risk stratification in MAD.

BACKGROUND: Power-controlled radiofrequency ablation with irrigated-tip catheters has been the norm for ventricular ablation for almost 2 decades. New catheter technology has recently integrated more accurate tissue temperature sensing enabling temperature-controlled irrigated ablation. We aimed to investigate the in vivo ablation parameters and lesion formation characteristics in ventricular myocardium using a novel temperature-controlled radiofrequency catheter. METHODS: Twenty canines were divided into 3 groups: 4 noninfarcted, acute (phase I); 8 noninfarcted, chronic (phase II); and 8 infarcted, chronic (phase III). Lesions were delivered with a temperature-controlled radiofrequency system utilizing a chemical vapor deposit diamond for efficient thermal diffusivity. In phase I, 17 ablation settings were tested (temperature set points, 50/60/70 °C; ablation duration, 15/30/60/90/120 s; and power limit, 30/50 W). Four and one of these sets of parameters were further tested in phases II and III, respectively. Lesions were assessed by ex vivo contrast-enhanced magnetic resonance imaging and gross pathology 5 weeks after ablation in phases II/III. RESULTS: Across all phases, 111 ablation lesions were delivered. Ablation with the power limit of 50 W, the temperature set point of 60 °C, and the duration of 60 s produced significantly larger and deeper lesions (mean, 569.2 mm 3 ; mean maximal depth, 9.8 mm) compared with 50 W/60 °C/30 s (mean, 340.4 mm 3 ; mean maximal depth, 8.3 mm) and 50 W/50 °C/60 s (mean, 227 mm 3 ; mean maximal depth, 6.9 mm), with P <0.05 for all pairwise comparisons. Ablation of infarcted myocardium in phase III (50 W/60 °C/30 s) resulted in smaller impedance and bipolar electrogram amplitude changes and lesion size compared with ablation in normal myocardium with the same settings. No steam pop, myocardial perforation, or char formation was observed in any of the 111 ablations across all phases. CONCLUSIONS: In vivo radiofrequency ablation in a canine model with a diamond-tip temperature-controlled catheter using a temperature set point of 60 °C and a power limit of 50 W created large lesions without steam pop risk in both normal and infarcted ventricular myocardia.

Background: Non-ischemic cardiomyopathies can be primary (p-NICM) which involves mainly the heart muscle or caused by systemic disease with heart muscle involvement as it is seen in systemic infiltrative diseases (i-NICM). There is limited data on the safety and in-hospital outcomes of ventricular tachycardia (VT) ablation in i-NICM. Methods: We identified patients who underwent VT ablation between 2018-2021 using the National Inpatient Sample Database. i-NICM include amyloidosis, hemochromatosis, or sarcoidosis. In-hospital complications include mortality, acute kidney injury (AKI), acute heart failure (AHF), bleeding, vasopressor use, blood transfusion and cardiac tamponade. Multivariate logistic regression analyses were performed. Results : There were 7,420 VT ablations, 7,235 had P-NICM and 185 had i-NICM. A multivariable analysis did not reveal any difference in mortality (adjusted odds ratio [aOR]: 0.81; 95% confidence interval 0.32-1.98; p=0.62), AHF aOR: 0.88 (0.41-1.81; p=0.69, AKI aOR:1.17 (0.83-1.65); p=0.36, blood transfusion aOR: 0.63 (0.25-1.59); p=0.33, vasopressor aOR: 0.86( 0.51-1.49); p=0.61 or pericardial effusion/ tamponade aOR: 1.16 (0.67-2.1); p=0.58 Figure Conclusion: Patients with i-NICM had similar in-hospital complications compared to P-NICM further supporting the safety of VT ablation in managing recurrent VT in patients with i-NICM.

Background Multimorbidity is common in patients with atrial fibrillation (AF), yet comorbidity patterns are not well documented. Methods The prevalence of 18 chronic conditions (6 cardiometabolic, 7 other somatic, 5 mental health) was obtained in patients with new-onset AF from 2013-2017 from a 27-county region and controls matched 1:1 on age, sex, and county of residence. For AF patients and controls separately, clustering of conditions and co-occurrence beyond chance was estimated (using the asymmetric Somers’ D statistic), overall and for ages <65, 65-74, 75-84, and ≥85 years. Results Among 16,509 patients with AF (median age 76 years, 57% men), few (4%) did not have any of the 18 chronic conditions, whereas nearly one-quarter of controls (23%) did not have any chronic conditions. Clustering of cardiometabolic conditions was common in both AF patients and controls, but clustering of other somatic conditions was more common in AF. Although the prevalence of most condition pairs was higher in AF patients, controls had a larger number of condition pairs occurring together beyond chance. In persons aged <65 years, AF patients more frequently exhibited concordance of condition pairs that included either pairs of somatic conditions or a combination of conditions from different condition groups. In persons aged 65-74 years, AF patients more frequently had pairs of other somatic conditions. Conclusion Patterns of co-existing conditions differed between patients with AF and controls, particularly in younger ages. A better understanding of the clinical consequences of multimorbidity in AF patients, including those diagnosed at younger ages, is needed.

Introduction: Tricuspid regurgitation (TR) is a common complication of right ventricle lead extraction (RVLE) in 5 to 10% of cases. This study aims to identify clinical outcomes such as predictors of heart failure hospitalization, need for tricuspid valve intervention, and death among patients with new severe TR after device lead removal (DLR). Methods: Patients who underwent DLR (pacemaker/ICD) between 3/1997 and 3/2024 were identified. Those who had an echocardiogram before and after RVLE with evidence of new severe TR were included. Cox univariable regression controlling for current age was used to assess association with death. Prentice Williams Peterson total time (PWPTT) Cox univariable regression was used to determine the rate of heart failure hospitalization up to three events per subject. Bivariable cox regression was used to control for ejection fraction for ICD and coil removal. Analysis was conducted using Stata IC16. Results: We identified 2,122 people who underwent RVLE, of whom 90 (4.24%) developed new severe TR and were included in the analysis. There were 68 hospitalizations among 38 people at a median of 2 years following lead extraction (IQR 0.57 to 4.5 years). The rate of hospitalization was 11.60 [9.14 to 14.71] per 100 person-years. Removal of an ICD was associated with increased hospitalization (HR 5.48 p<0.001) but not mortality (HR 1.21, p=0.707). Removal of a single coil ICD lead was associated with increased hospitalization rate (HR 3.01, p=0.031) but not mortality (HR =0.51, p=0.380). Removal of dual coil ICD lead was associated with more than a tenfold increase in hospitalization rate (HR 11.55, p=0.001) and four times the mortality rate (HR 4.05, p=0.031) (Figures 1&2). The presence of an abandoned (pacemaker/ICD) lead was associated with increased hospitalization (HR 5.75, p=0.004) and mortality (HR4.95, p=0.034). There was no change in hospitalization rate following tricuspid valve replacement (HR 1.33, p=0.716, n=18). Conclusion: Among people with new severe TR following DLR, the characteristics of the leads are strongly correlated with morbidity and mortality.