NEW YORK (Reuters Health) – Patients with unprotected left main disease and right coronary artery chronic total occlusion (CTO) undergoing percutaneous coronary intervention (PCI) face an increased risk of mortality, researchers from Italy report in the July 5th Journal of the American College of Cardiology.

“Right coronary CTO in patients with unprotected left main disease is frequent, has a strong impact on survival, and should be not neglected in the revascularization strategy,” Dr. David Antoniucci from Careggi Hospital, Florence, Italy told Reuters Health in an email.

Dr. Antoniucci and colleagues investigated whether right coronary artery CTO carries prognostic implications in 330 patients undergoing drug-eluting stent-supported PCI for unprotected left main disease.

Nearly a quarter of the patients (78 patients, 24%) had right coronary artery CTO, and these patients had a higher risk profile compared with patients without right coronary artery CTO.

Complete revascularization rates were significantly higher in patients without right coronary artery CTO (88%) than in patients with right coronary artery CTO (44%)(p<0.001).

The cardiac mortality rate at 6 months was significantly higher in patients with right coronary artery CTO (12.8%) than in patients without right coronary artery CTO (3.6%)(p=0.002). The cardiac mortality rate at 6 months did not differ significantly between right coronary artery CTO patients who were successfully treated (8.6%) and those with untreated coronary artery CTO or failed right coronary artery CTO PCI (16.3%)(p=0.311).

Cardiac survival rates at 3 years were significantly higher in patients without right coronary artery CTO (89.7%) than in patients with right coronary artery CTO (76.4%)(p=0.003).

Right coronary artery CTO and EuroSCORE were the only 2 independent predictors of 3-year cardiac mortality, and right coronary artery CTO remained a significant predictor of cardiac death (hazard ratio, 2.37) after adjusting for the propensity score.

“There is growing evidence that successful treatment of coronary CTO provides a strong benefit in terms of survival, and in most cases CTO should not be managed medically,” Dr. Antoniucci said.

“Surgical revascularization should be considered in patients with failed PCI or nonattempted right coronary CTO PCI because of renal insufficiency or low likelihood of PCI success,” Dr. Antoniucci said. “Whatever the type of revascularization (surgical or percutaneous) the goal should be the achievement of a complete revascularization at least in patients with evidence of myocardial viability in the right coronary artery territory.”

J Am Coll Cardiol 2011;58:125-130.