Successful PCI for Chronic Total Occlusion of the LAD is Associated with Improved Long-term Survival

June 18, 2008 By Vijayalakshmi Kunadian MBBS MD MRCP [mailto:vkunadian@perfuse.org]

JACC Interventions-Kansas City: A new study demonstrates that percutaneous coronary intervention for chronic total occlusion of the left anterior descending artery is associated with improved long-term survival compared with PCI to the right coronary and the circumflex arteries. Percutaneous coronary intervention (PCI) for chronic total occlusion (CTO) has been demonstrated to be associated with improvement in the anginal status of patients, improved ejection fraction, reduced risk of recurrent myocardial infarction and improved survival rates. Advances in the techniques to recanalize the chronically occluded arteries have improved the PCI success rates. Safley and colleagues from Kansas City in a new study published recently in JACC Interventions investigated if there were differences in long-term survival with respect to the target vessel that was intervened and compared the outcomes among patients undergoing PCI of single CTO across each of the three major epicardial coronary arteries.

A total of 2,608 patients who underwent PCI of a single CTO from June 1980 to May 2004 were included in this study. CTO was defined as a lesion that had TIMI flow grade 0/1 on initial angiography. Procedural success was defined as angiographic success (successful balloon dilatation with <40% residual stenosis) with no in-hospital major adverse cardiac event (death, myocardial infarction with new Q waves or urgent target vessel revascularization-TVR). The primary endpoint of the study was survival at 5 years, compared across target vessel groups stratified by procedural success.

The mean (SD) age of study patients was 62 (12) years. 936 (36%) underwent PCI to LAD, 682 (26%) had PCI to the circumflex artery (LCX) and 990 (38%) had PCI to the right coronary artery (RCA). More patients who had PCI to the LCX were men (p=0.005) and had previous CABG (p<0.001). Stents and glycoprotein IIb/IIIa inhibitors were used less frequently in all three groups. The angiographic success was 77% in the LAD, 76% in the LCX groups and 72% in the RCA groups (p=0.03) and the procedural success was 75% in the LAD and LCX groups and 71% in the RCA groups (p=0.06). Patients who had failed PCI to the LAD were more often older men who smoked and had undergone previous CABG compared with those who had a successful procedure. In-hospital death occurred more often following LAD PCI (1.9%) compared with PCI to LCX (0.4%) and RCA (0.5%), p=0.002. Furthermore, patients who underwent PCI to the LAD had an increased in-hospital TVR (1.4% vs. 0.3% vs. 0.3%, p=0.006) and MACE (4% vs. 1.6% vs. 1.9%, p=0.003) rates compared with those who underwent PCI to LCX and RCA. Patients who had PCI to the RCA more often had in-hospital CABG (3.5%, p=0.04).

Successful procedure to the LAD compared with failure was associated with improved 5 year survival rates (88.9% vs. 80.2%, p<0.001) but not in the LCX (86.1% vs. 82.1%, p=0.21) and RCA (87.7% vs. 84.9%, p=0.23). Even after adjustment for demographic and procedural differences between success and failure groups, successful CTO PCI was associated with improved long-term survival in the LAD group (HR: 0.61, 95% CI 0.42-0.89, p<0.001) but not in the LCX (HR: 0.86, 95% CI 0.55-1.35) and RCA (HR: 0.82 95% CI 0.57-1.19) groups.

This study has several limitations. This is an observational study and only a very small proportion of patients was treated with stenting and had treatment with GPIIbIIIa inhibitors. Recently, there have been significant developments in the techniques to open up the CTOs. Despite the limitations, this study provides an important insight and extends previous observations to the fact that the LAD is a prognostically significant vessel compared with the LCX and the RCA. The authors conclude that successful CTO PCI to the LAD is associated with an improvement in long-term survival compared with failed PCI to the LAD and this difference was not so evident among patients undergoing CTO PCI to the LCX and the RCA.

Source

 * 1) http://interventions.onlinejacc.org/cgi/content/abstract/1/3/295