Effect of concomitant coronary artery disease on procedural and late outcomes of transcatheter aortic valve implantation

Background: Previous coronary artery bypass grafting increases predicted operative risk for conventional valve replacement, according to the Society of Thoracic Surgeons risk algorithm. Additionally, the presence of coronary artery disease (CAD) has been demonstrated to increase procedural risk with conventional aortic valve replacement. Significant coexisting CAD requires preemptive percutaneous coronary intervention (PCI) in patients under consideration for transcatheter aortic valve implantation (TAVI). This study examined the impact of previous coronary artery bypass grafting or PCI on procedural outcomes and overall survival in patients having TAVI.

Methods: Two hundred and one high-risk patients were enrolled in two international feasibility studies from December 2005 to February 2008 for the treatment of aortic stenosis using TAVI. Thirty patients were excluded from analysis due to failure to successfully deploy the valve in the aortic annulus. Data were collected concurrently using an ad hoc database that included operative and long-term survival. Previous cardiovascular intervention prior to TAVI was used to identify the existence of concomitant CAD. Logistic regression along with Kaplan-Meier estimates were employed to establish the association between CAD and survival from TAVI.

Results: Overall mortality after TAVI was significantly higher among the CAD group (35.7%) in contrast with the non-CAD patients (18.4%), p = 0.01. Logistic regression analysis found that patients who had CAD were 10.1 times more likely to die (95% confidence interval 2.1 to 174.8) within 30 days of the procedure than those who did not. Proportional hazards analysis established that the risk of dying at any point in time was 2.3 times higher among the patients with CAD (95% confidence interval 1.29 to 4.17). Kaplan-Meier survival curves demonstrate improved long-term survival among patients without CAD.

Conclusions: Coexisting coronary artery disease negatively impacts procedural outcomes and long-term survival in patients undergoing TAVI, and implies that risk assessment and anticipated outcomes might be inaccurate due to stratification as isolated aortic valve replacement rather than AVR+CABG. Comparison of procedural outcomes, based on operative approach without controlling for unequal distribution of CAD in the cohorts, are likely invalid.