ETIOLOGY OF CARDIAC ARREST IN THE ABSENCE OF MANIFEST STRUCTURAL HEART DISEASE - UPDATE FROM THE CASPER PROSPECTIVE COHORT

Abstract

BACKGROUND: In patients requiring cardiac resynchronization therapy (CRT), the most common method of left ventricular (LV) lead implantation is percutaneous. However, in cases of poor venous access or failed transvenous LV lead placement, an epicardial approach through a mini thoracotomy is recommended. In general, the results of the two approaches are thought to be similar. To date, the indications and underlying pathology of patients requiring epicardial LV lead placement are not well known. The aim of this study is to further delineate baseline patient characteristics and long term outcomes in those receiving epicardical LV lead placement. METHODS AND RESULTS: A retrospective review of 500 consecutive CRT devices at a single center from January 2008 to March 2014 was undertaken. We identified 25 (5%) patients with epicardial LV lead placement. Median age was 61 +13 years, 19 (76%) were male 6 (24%) female. The most common underlying pathology was non-ischemic cardiomyopathy 19 (75%). The number one indication for epicardial lead placement was failed coronary sinus cannulation in 16 (64%), poor venous access in 4 (16%), and other in 5 (20%). Average hospital stay was 4.9 days + 4.6 days post implantation for patients with epicardial lead placement versus 1.1 days + 0.7 days in the age, sex matched percutaneous group (p 1⁄4 0.00041, two tailed t-test). Average follow up of patients from time of epicardial lead implantation was 595 days + 274 days. A higher mortality was observed in patient receiving an epicardial lead when compared to patients with transvenous lead (11 (44%) vs. 90 (19%), p1⁄40.0079). Patients died on average 622 + 293 days from operation date with improvement in patient functional class in 7 (28%) patients. There were no significant changes in ejection fraction (EF) pre and post epicardial lead implantation (21% versus 23%, p1⁄40.19) or the degree of mitral regurgitation (MR) pre and post epicardial LV lead placement (mild to moderate versus moderate MR). CONCLUSION: Failure to cannulate the coronary sinus is the most common indication for epicardial LV lead placement. These patients are more likely to be males with non ischemic cardiomyopathy and as such these implantations should be undertaken in centers where an epicardial approach is available. Patients receiving epicardial LV lead on average have longer hospital stays post implantation and have higher long term mortality.