Willerson, James T.

Abstract The concept that cell-based repair of myocardial injury might be possible was introduced almost two decades ago; however, the field of cardiovascular reparative medicine has been criticized as translation to clinically effective approaches has been slow. The recent retraction of a series of papers has further impacted perception of this area of research. As researchers, clinicians, and teachers in this field, we felt it incumbent to critically appraise the current state of cardiac cell repair, determine what can be learned from past mistakes, and formulate best practices for future work. This special communication summarizes an introspective assessment of what has fallen short, how to prevent similar issues, and how the field might best move forward in the service of science and patients.

Background— Restenosis prediction from published studies is hampered by inadequate sample size and incomplete angiographic follow-up. The prediction of restenosis with the existing variables is poor. The aim of the present study was to include the clinical and angiographic variables commonly associated with angiographic restenosis and develop a prediction model for restenosis from the PRESTO database. Methods and Results— This study included 1312 patients with a single lesion enrolled in the angiographic substudy of the PRESTO trial. We constructed 2 risk scores. The first used preprocedural variables (female gender, vessel size [≤2.5 mm, 2.5 to 3 mm, 3 to 3.5 mm, 3.5 to 4 mm, >4 mm], lesion length >20 mm, diabetes, smoking status, type C lesion, any previous percutaneous coronary intervention [PCI], and unstable angina) derived from previous studies. Estimated restenosis rates and corresponding variability for each possible level of the resultant risk score were obtained via bootstrapping techniques. The area under the receiver-operator characteristic (ROC) curve was 0.63, indicating modest discriminatory ability to predict restenosis. The second approach constructed a multiple logistic regression model considering significant univariate clinical and angiographic predictors of restenosis identified from the PRESTO database (treated diabetes mellitus, nonsmoker, vessel size, lesion length, American College of Cardiology/American Heart Association type C lesion, ostial location, and previous PCI). The area under the ROC curve for this risk score was also 0.63. Conclusions— The preprocedural clinical and angiographic variables from available studies and from the PRESTO trial have only modest predictive ability for restenosis after PCI.

Background— Diabetes portends an adverse prognosis in patients undergoing percutaneous coronary intervention (PCI). Whether improvements in current clinical practice (stents, IIb/IIIa antagonists) have resulted in substantial improvement of these outcomes remains an issue. The aim of this study was to determine the influence of diabetes on 9-month outcomes of patients undergoing PCI in the current era. Methods and Results— The 11 482 patients enrolled in the Prevention of REStenosis with Tranilast and its Outcomes (PRESTO) Trial were stratified according to the presence (n=2694) or absence (n=8798) of diabetes. Diabetic patients were older; were more likely to be female; had a higher proportion of congestive failure, hypertension, prior CABG, and unstable angina; and had higher body mass index and lower ejection fraction than nondiabetic patients ( P <0.01 for all comparisons). The degree of multivessel disease was similar between the two groups. American College of Cardiology/American Heart Association type C lesions were more common in diabetic patients (17% versus 15%, P <0.01). Angiographic and procedural success rates and in-hospital events were similar between the two groups. The primary end point of death, myocardial infarction, or target vessel revascularization (TVR) was analyzed as time-to-first event within 9 months of the index PCI. After adjusting for certain baseline characteristics, diabetes was independently associated with death at 9 months (relative risk [RR], 1.87; 95% CI, 1.31 to 2.68, P <0.01) and with an increased likelihood of TVR (RR, 1.27; 95% CI, 1.14 to 1.42, P <0.01), as well as the composite end point of death/myocardial infarction/TVR (RR, 1.26; 95% CI, 1.13 to 1.40, P <0.01). Conclusions— Despite advances in interventional techniques, diabetes remains a significant independent predictor of adverse events in the intermediate term after PCI.

Background— Restenosis after percutaneous coronary intervention (PCI) is a major problem affecting 15% to 30% of patients after stent placement. No oral agent has shown a beneficial effect on restenosis or on associated major adverse cardiovascular events. In limited trials, the oral agent tranilast has been shown to decrease the frequency of angiographic restenosis after PCI. Methods and Results— In this double-blind, randomized, placebo-controlled trial of tranilast (300 and 450 mg BID for 1 or 3 months), 11 484 patients were enrolled. Enrollment and drug were initiated within 4 hours after successful PCI of at least 1 vessel. The primary end point was the first occurrence of death, myocardial infarction, or ischemia-driven target vessel revascularization within 9 months and was 15.8% in the placebo group and 15.5% to 16.1% in the tranilast groups ( P =0.77 to 0.81). Myocardial infarction was the only component of major adverse cardiovascular events to show some evidence of a reduction with tranilast (450 mg BID for 3 months): 1.1% versus 1.8% with placebo ( P =0.061 for intent-to-treat population). The primary reason for not completing treatment was ≥1 hepatic laboratory test abnormality (11.4% versus 0.2% with placebo, P <0.01). In the angiographic substudy composed of 2018 patients, minimal lumen diameter (MLD) was measured by quantitative coronary angiography. At follow-up, MLD was 1.76±0.77 mm in the placebo group, which was not different from MLD in the tranilast groups (1.72 to 1.78±0.76 to 80 mm, P =0.49 to 0.89). In a subset of these patients (n=1107), intravascular ultrasound was performed at follow-up. Plaque volume was not different between the placebo and tranilast groups (39.3 versus 37.5 to 46.1 mm 3 , respectively; P =0.16 to 0.72). Conclusions— Tranilast does not improve the quantitative measures of restenosis (angiographic and intravascular ultrasound) or its clinical sequelae.