Three-year survival following multivessel percutaneous coronary intervention with bare-metal or drug-eluting stents in unselected patients

Propensity Score-Based Methods in Comparative Effectiveness Research on Coronary Artery Disease

This review examines the conduct and reporting of observational studies using propensity score-based methods to compare coronary artery bypass grafting (CABG), percutaneous coronary intervention (PCI), or medical therapy for patients with coronary artery disease. A systematic selection process identified 48 studies: 20 addressing CABG versus PCI; 21 addressing bare-metal stents versus drug-eluting stents; 5 addressing CABG versus medical therapy; 1 addressing PCI versus medical therapy; and 1 addressing drug-eluting stents versus balloon angioplasty. Of 32 studies reporting information on variable selection, 7 relied exclusively on statistical criteria for the association of covariates with treatment, and 5 used such criteria to determine whether product or nonlinear terms should be included in the propensity score model. Twenty-five (52%) studies reported assessing covariate balance using the estimated propensity score, but only 1 described modifications to the propensity score model based on this assessment. The over 400 variables used in the 48 propensity score models were classified into 12 categories and 60 subcategories; only 17 subcategories were represented in at least half of the propensity score models. Overall, reporting of propensity score-based methods in observational studies comparing CABG, PCI, and medical therapy was incomplete; when adequately described, the methods used were often inconsistent with current methodological standards.

Use of clopidogrel with or without aspirin in patients taking oral anticoagulant therapy and undergoing percutaneous coronary intervention: an open-label, randomised, controlled trial

BACKGROUND

If percutaneous coronary intervention (PCI) is required in patients taking oral anticoagulants, antiplatelet therapy with aspirin and clopidogrel is indicated, but such triple therapy increases the risk of serious bleeding. We investigated the safety and efficacy of clopidogrel alone compared with clopidogrel plus aspirin.

METHODS

We did an open-label, multicentre, randomised, controlled trial in 15 centres in Belgium and the Netherlands. From November, 2008, to November, 2011, adults receiving oral anticoagulants and undergoing PCI were assigned clopidogrel alone (double therapy) or clopidogrel plus aspirin (triple therapy). The primary outcome was any bleeding episode within 1 year of PCI, assessed by intention to treat. This study is registered with ClinicalTrials.gov, number NCT00769938.

FINDINGS

573 patients were enrolled and 1-year data were available for 279 (98·2%) patients assigned double therapy and 284 (98·3%) assigned triple therapy. Mean ages were 70·3 (SD 7·0) years and 69·5 (8·0) years, respectively. Bleeding episodes were seen in 54 (19·4%) patients receiving double therapy and in 126 (44·4%) receiving triple therapy (hazard ratio [HR] 0·36, 95% CI 0·26-0·50, p<0·0001). In the double-therapy group, six (2·2%) patients had multiple bleeding events, compared with 34 (12·0%) in the triple-therapy group. 11 (3·9%) patients receiving double therapy required at least one blood transfusion, compared with 27 (9·5%) patients in the triple-therapy group (odds ratio from Kaplan-Meier curve 0·39, 95% CI 0·17-0·84, p=0·011).

INTERPRETATION

Use of clopiogrel without aspirin was associated with a significant reduction in bleeding complications and no increase in the rate of thrombotic events.

FUNDING

Antonius Ziekenhuis Foundation, Strect Foundation.

Long-term outcomes with cobalt-chromium bare-metal vs. drug-eluting stents: the REgistro regionale AngiopLastiche dell'Emilia-Romagna registry

OBJECTIVE

To compare the long-term efficacy of cobalt-chromium bare-metal stents (CCSs) with that of first-generation drug-eluting stents (DESs) in patients within a large real-world multicentre registry.

METHODS

The incidence of major adverse cardiac events [death, acute myocardial infarction, and target-vessel revascularization (TVR)] and angiographic stent thrombosis were assessed in consecutive patients undergoing percutaneous coronary intervention with CCS (n = 1103) or DES (n = 5195) during 2-year follow-up. Propensity score-adjusted outcomes, overall and in patients with low (≤ 10%), intermediate (10-15%), and high (>15%) 1-year restenosis risk, were estimated.

RESULTS

DES-treated patients had significantly higher rates of diabetes, longer lesions, and smaller vessel diameters than CCS-treated patients (all P < 0.0001). However, CCS patients were older and presented a higher rate of hypertension, previous myocardial infarction, and heart failure (all P < 0.01). At 2 years, adjusted rates of myocardial infarction, death, and cumulative-stent thrombosis were similar for DES and CCS. DES provided statistically significant (P < 0.01) reductions in TVR and adjusted major adverse cardiac event rates (9.7 and 17.2%, respectively) compared with CCS (13.2 and 21.2%, respectively). In patients at highest and intermediate risk of restenosis, adjusted TVR rates were significantly (P < 0.01) lower with DES (12.2 and 8.9%, respectively) than CCS (19.9 and 17.1%, respectively), but rates were similar in low-risk patients.

CONCLUSION

DESs were more effective than CCSs in lowering TVR rates in patients with an intermediate-high baseline restenosis risk.