School of Medicine

Chronic thromboembolic pulmonary hypertension (CTEPH) is a debilitating disease, now potentially curable with the advent of pulmonary thromboendarterectomy (PTE). This study aimed to identify the prevalence of cardiac implantable electronic devices (CIEDs) in the PTE population and describe associated disease burden. The contribution of CIEDs to thrombosis in this patient population has not been previously studied. The charts of 982 CTEPH patients, who underwent PTE between January 1, 2009 and December 31, 2015 at UC San Diego (UCSD) Medical Center, were reviewed for pacemaker or ICD leads implanted prior to surgery. All statistical analyses were completed using SPSS software. Continuous variables were analyzed with t-tests for normally distributed data; categorical variables were compared with chi-squares. Among 982 total CTEPH patients who underwent PTE, 14 had pacemakes and 3 had ICD leads, for a total of 17 CIEDs and a prevalence of 1.7%. Of these 17 CIEDs, 6 devices were extracted intraoperatively, and 5 of 6 devices were replaced with epicardial leads. Further more, of the 950 patients classified by intraoperative UCSD Level, 12 of 17 (70.6%) patients with CIEDs had distal disease versus 241 of 933 (25.8%) patients without CIEDs (p=.0002). The prevalence of known venous thromboemoblism (VTE) was 50% in CIED patients compared to 78.6% in patients without CIEDs (p=.018). There were no significant differences in demographics, preoperative hemodynamics, and postoperative hemodynamics between CTEPH patients with CIEDs and those without CIEDs. at 1.7%, the prevalence of CIEDs in the PTE population is higher than previously reported values, which estimated CIED prevalence between 0.16% and 0.47% in the general population. Moreover, CTEPH patients with CIEDs are more strongly associated with distal disease burden and less likely to have had prior VTE, suggesting that CIEDs may be a nidus for small clots which embolize distally in the pulmonary vasculature.