Validation of a risk score for target vessel revascularization after coronary stent implantation

Our aim was to validate a risk score for new target vessel revascularization (TVR) after bare-metal stent (BMS) implantation.

The risk score was developed in a cohort of patients previously treated with BMS at our institution. This risk score ranges from 0 to 5 points, according to the presence of diabetes mellitus (1 point), reference vessel diameter (> 3.5 mm = 0 points; 3-3.5 mm = 1; < 3 mm = 2) and lesion length (< or = 10 mm = 0 points; 10-20 mm = 1; > 20 mm = 2). Patients included in the validation cohort were treated between January and December 2005. Patient characteristics and 1-year clinical follow up were prospectively recorded into a dedicated database. A new coronary angiography was performed only when recurrent ischemia was suspected.

The mean age of the 491 patients included was 61 +/- 10.5 years, and 35% were women. Diabetes mellitus was present in 22%, a previous percutaneous coronary intervention in 12% and previous myocardial infarction in 35%. The mean reference vessel diameter was 2.80 +/- 0.56 mm and the mean lesion length was 12.45 +/- 6.3 mm. The overall 1-year TVR rate was 13.9%. TVR rates increased with each score level: Score = 0, TVR = 0% (n = 16); Score 1 = 5.3% (n = 48); Score 2 = 12% (n = 170); Score 3 = 14% (n = 146); and Score 4/5 = 25% (n = 54); (p = 0.008).

The risk score was significantly associated with TVR rates and can be used as a simple clinical tool to identify those patients at a low risk for a new revascularization procedure.