Accounting for the mortality benefit of drug-eluting stents in percutaneous coronary intervention: a comparison of methods in a retrospective cohort study

<p>Abstract</p> <p>Background</p> <p>Drug-eluting stents (DES) reduce rates of restenosis compared with bare metal stents (BMS). A number of observational studies have also found lower rates of mortality and non-fatal myocardial infarction with DES compared with BMS, findings not observed in randomized clinical trials. In order to explore reasons for this discrepancy, we compared outcomes after percutaneous coronary intervention (PCI) with DES or BMS by multiple statistical methods.</p> <p>Methods</p> <p>We compared short-term rates of all-cause mortality and myocardial infarction for patients undergoing PCI with DES or BMS using propensity-score adjustment, propensity-score matching, and a stent-era comparison in a large, integrated health system between 1998 and 2007. For the propensity-score adjustment and stent era comparisons, we used multivariable logistic regression to assess the association of stent type with outcomes. We used McNemar's Chi-square test to compare outcomes for propensity-score matching.</p> <p>Results</p> <p>Between 1998 and 2007, 35,438 PCIs with stenting were performed among health plan members (53.9% DES and 46.1% BMS). After propensity-score adjustment, DES was associated with significantly lower rates of death at 30 days (OR 0.49, 95% CI 0.39 - 0.63, <it>P </it>< 0.001) and one year (OR 0.58, 95% CI 0.49 - 0.68, <it>P </it>< 0.001), and a lower rate of myocardial infarction at one year (OR 0.72, 95% CI 0.59 - 0.87, <it>P </it>< 0.001). Thirty day and one year mortality were also lower with DES after propensity-score matching. However, a stent era comparison, which eliminates potential confounding by indication, showed no difference in death or myocardial infarction for DES and BMS, similar to results from randomized trials.</p> <p>Conclusions</p> <p>Although propensity-score methods suggested a mortality benefit with DES, consistent with prior observational studies, a stent era comparison failed to support this conclusion. Unobserved factors influencing stent selection in observational studies likely account for the observed mortality benefit of DES not seen in randomized clinical trials.</p

Incidence and Severity of Coronary Artery Disease in Patients with Atrial Fibrillation Undergoing First-Time Coronary Angiography

In standard reference sources, the incidence of coronary artery disease (CAD) in patients with atrial fibrillation (AF) ranged between 24 and 46.5%. Since then, the incidence of cardiovascular risk factors (CRF) has increased and modern treatment strategies ("pill in the pocket") are only applicable to patients without structural heart disease. The aim of this study was to investigate the incidence and severity of CAD in patients with AF.From January 2005 until December 2009, we included 261 consecutive patients admitted to hospital with paroxysmal, persistent or permanent AF in this prospective study. All patients underwent coronary angiography and the Framingham risk score (FRS) was calculated. Patients with previously diagnosed or previously excluded CAD were excluded.The overall incidence of CAD in patients presenting with AF was 34%; in patients >70 years, the incidence of CAD was 41%. The incidence of patients undergoing a percutaneous coronary intervention (PCI) or coronary artery bypass graft (CABG) was 21%. Patients with CAD were older (73±8 years vs 68±10 years, p = 0.001), had significantly more frequent hypercholesterolemia (60% vs 30%, p<0.001), were more frequent smokers (26% vs 13%, p = 0.017) and suffered from angina more often (37% vs 2%, p<0.001). There was a significant linear trend among the FRS categories in percentage and the prevalence of CAD and PCI/CABG (p<0.0001).The overall incidence of CAD in patients presenting with AF was relatively high at 34%; the incidence of PCI/CABG was 21%. Based upon increasing CRF in the western world, we recommend a careful investigation respecting the FRS to either definitely exclude or establish an early diagnosis of CAD--which could contribute to an early and safe therapeutic strategy considering type Ic antiarrhythmics and oral anticoagulation

Anticoagulant and antiplatelet therapy use in 426 patients with atrial fibrillation undergoing percutaneous coronary intervention and stent implantation implications for bleeding risk and prognosis

ObjectivesThis study was designed to review outcomes in relation to antithrombotic therapy management strategies for patients with atrial fibrillation (AF) who undergo percutaneous coronary intervention (PCI) with stenting.BackgroundThere is limited evidence on the optimal antithrombotic therapy management strategies for patients with AF who undergo PCI with stenting.MethodsWe reviewed 426 patients (70.9% men, mean age 71.5 ± 8.5 years) with AF undergoing PCI with stenting between 2001 and 2006. We recorded clinical and demographic characteristics of the patients, stroke risk factors, and antithrombotic therapy use before PCI and at discharge. Clinical follow-up was performed, and all bleeding episodes, thromboembolism, and major adverse cardiac events (MACE) (i.e., death, acute myocardial infarction, or target lesion revascularization) were recorded.ResultsThe most commonly associated comorbidities were hypertension (74.5%), diabetes mellitus (40.2%), chronic renal failure (14.9%), and congestive heart failure (26.7%); 80% of patients had ≥2 stroke risk factors. Of the drugs prescribed at discharge, aspirin plus clopidogrel were used in 174 patients (40.8%), whereas 213 patients (50%) were discharged with triple therapy (coumarins, aspirin, and clopidogrel). Complete follow-up was achieved in 87.5% (median 594 days; range 0 to 2,190). The incidence of adverse events was high (36.6%), with major bleeding in 12.3%, thromboembolic events in 4.2%, and MACE in 32.3%. All-cause mortality was high (22.6%). In a multivariate analysis, non-anticoagulation with coumarins increased mortality (17.8% vs. 27.8%; hazard ratio [HR] = 3.43; 95% confidence interval [CI] 1.61 to 7.54; p = 0.002) and MACE (26.5% vs. 38.7%; HR = 4.9; 95% CI 2.17 to 11.1; p < 0.01) In a Cox-regression analysis, non-anticoagulation (p < 0.01) and age (p = 0.02) were independent predictors of MACE.ConclusionsPatients with AF undergoing PCI with stenting represent a high-risk population because of age, comorbidities, and presence of stroke risk factors. These patients have a high mortality and MACE rate, which is reduced by anticoagulation therapy