Is incomplete revascularization associated with decreased survival rates?

The authors evaluated the impact of incomplete revascularization on mortality (death) in patients receiving stents, particularly drug-eluting stents.

Studies using data from the era of drug-eluting stents have in general found that incomplete revascularization (incomplete restoration of blood flow) was associated with a greater risk of major cardiac adverse events (death, repeat revascularization, or heart attack) after percutaneous coronary intervention (a non-surgical procedure used to treat the narrowed coronary arteries of the heart). Drug-eluting stents are small medication-coated metal tubes that can be inserted into the narrowed segment of the artery. The drug coating the stent typically works to prevent tissue growth, markedly reducing the rate of artery re-narrowing. However, study results have been inconsistent.

This study examined the impact of incomplete revascularization on mortality for approximately 5 years using data from a large patient population.

In the study population, 6,511 patients who were completely revascularized were matched to 6,511 patients who were incompletely revascularized. 87.3% of patients received drug-eluting stents, 5.6% of patients received bare-metal stents (stents without the drug coating), and 7% of patients received both types of stent.

During the study follow-up, 1,045 of the incomplete revascularization group died compared to 888 of the complete revascularization group. Incomplete revascularization was associated with a 16% greater risk of death. The 5-year survival rate was 79.3% in the incomplete revascularization group compared to 81.4% in the complete revascularization group.

Incomplete revascularization of one vessel was associated with a 13% increased risk of death compared to complete revascularization, while incomplete revascularization of multiple vessels was associated with a 27% increased risk. The 5-year survival rate for those with incomplete revascularization of one vessel was 79.8% compared to 81.4% in those with complete revascularization. 5-year survival rates for those with incomplete revascularization in multiple vessels was 77% compared to 81% in those with complete revascularization.

In a subanalysis of only those who received drug-eluting stents, the 5-year survival rate for incomplete revascularization was 78.7% compared to 80.9% for complete revascularization. Incomplete revascularization was associated with a 20% increased risk of death. Single-vessel incomplete revascularization was associated with a 16% increased risk of death, while multiple-vessel incomplete revascularization was associated with a 43% increased risk.

The authors concluded that incomplete revascularization is associated with an increased mortality risk after stenting compared to complete revascularization.