PO-03-047 RIGHT VENTRICULAR LEAD DISTENSION AND MALFUNCTION IN ARRHYTHMOGENIC RIGHT VENTRICULAR CARDIOMYOPATHY

Abstract

Right ventricular (RV) dilatation in the setting of arrhythmogenic right ventricular cardiomyopathy (ARVC) can occur over time. This enlargement can affect implantable cardioverter defibrillator (ICD) leads, resulting in lead distension and malfunction. We aimed to study changes that occur in ICD leads in patients with ARVC as seen on chest radiography and to correlate with lead malfunction over time. Patients in the ARVC registry at the Hospital of the University of Pennsylvania were screened. Inclusion criteria included the presence of a transvenous ICD or pacemaker with at least one RV lead and two chest radiographs performed at least one year apart. We collected data on demographics, imaging studies, and device interrogations including history of lead malfunction. We evaluated the earliest and latest chest radiographs for lead distension and loss of slack. Two transthoracic echocardiograms (TTE) at least one year apart were reviewed to evaluate change in RV size. We used descriptive statistics for analysis. We screened 105 consecutive patients with ARVC. We excluded 68 patients due to a lack of chest radiographs at least one year apart and 2 patients for ambiguous diagnoses. A total of 35 patients met inclusion criteria; mean age was 59 ± 18 years, and 8 (23%) were female. Mean duration between the first and last chest radiographs was 8.7 ± 6.6 years. Mean age of the RV leads was 11 ± 7.1 years at the time of the second chest radiograph. A total of 24 (69%) patients showed gross loss of lead slack and lead distension over time, and the remaining 11 (31%) patients had no change. Among the 24 patients with radiographic changes, 17 (71%) developed lead malfunction over time defined by elevated pacing thresholds, abnormal pacing impedance or lead noise (OR 2.9, 95% CI 0.66-12, p = 0.15). Among the 11 patients without radiographic changes, 5 (45%) had lead malfunction. Mean duration between the two compared TTE studies was 10.3 ± 7.2 years. RV dilatation occurred in 32/35 (91%) patients. Of the patients with radiographic changes, 11/24 (46%) showed progression from mild or moderate to severe RV dilatation compared to 1/11 (9%) in the group without radiographic changes. RV dilatation and lead distension occur frequently in patients with ARVC. The rate of lead malfunction is also relatively high over this time period. Whether there is a causal association between the two, or an ability to mitigate this risk with use of extra slack, requires further study.