Differential outcomes after sirolimus-eluting stent implantation: comparing on-label versus off-label patients in the 'real world'.

BACKGROUND: Randomized controlled trials indicate that sirolimus-eluting stents (SES) reduce the rates of restenosis and need for subsequent revascularization procedures, but patients enrolled in randomized trials represent a highly selected population. This study examined the performance of SES in a 'real world' setting by comparing the outcomes of trial-eligible versus ineligible patients undergoing percutaneous coronary intervention. METHODS: From the US commercial introduction of SES in April 2003 until December 2003, all patients that received an SES at our institution were followed in a prospective registry (n=838). For the purpose of this analysis, the registry population was divided into two groups based on the inclusion and exclusion criteria of the stenosis in a native coronary artery (SIRIUS) trial. The primary endpoint of the study was the rate of target lesion revascularization (TLR) at follow-up. Secondary endpoints included major adverse cardiac events (MACE) such as cardiac death, myocardial infarction, and target vessel revascularization. Clinical follow-up was complete for 92% of patients with a median duration of 14.2 months. RESULTS: Overall, 296 patients (35.3%) met entry criteria for the SIRIUS trial and thus comprised the SIRIUS eligible group. Patients in the SIRIUS ineligible group (n=542) were more likely to have chronic kidney disease and earlier bypass surgery and had longer mean stent length. At 1 year, TLR occurred in 3.0% of the SIRIUS eligible population and in 9.2% of the SIRIUS ineligible group (P=0.001). The secondary endpoint of cumulative MACE occurred in 6.6% of the SIRIUS eligible versus in 17.7% of the SIRIUS ineligible population (P<0.001). Two patients (0.4%) in the SIRIUS ineligible group had a late stent thrombosis on days 39 and 99, respectively, versus none in the SIRIUS eligible group. CONCLUSION: Among 'real world' patients treated with SES, the incidence of TLR and MACE at 1 year was substantially greater among SIRIUS ineligible patients compared with SIRIUS eligible patients. These findings confirm that pivotal clinical trials of drug-eluting stents tend to enroll low-risk patients and that the estimated rates of TLR and MACE derived from such trials may not reflect subsequent outcomes with unrestricted clinical use.

Comparison of outcomes using sirolimus-eluting stenting in diabetic versus nondiabetic patients with comparison of insulin versus non-insulin therapy in the diabetic patients.

The effect of insulin therapy on adverse cardiovascular outcomes in diabetic patients has been debated and a reduced benefit in clinical restenosis outcomes after sirolimus stenting has been reported among diabetic patients requiring insulin therapy. We analyzed 297 diabetic patients receiving sirolimus-eluting stents, including 115 (39%) on insulin therapy, and compared outcomes with 541 nondiabetic patients treated consecutively during the same interval. The rates of target lesion revascularization (9.5% vs 3.5%, p = 0.003) and cardiac death or myocardial infarction (MI, 7.1% vs 3.1%, p = 0.012) were significantly higher for diabetic patients. Insulin treatment was independently associated with increased risk for target lesion revascularization (odds ratio [OR] 2.48, 95% confidence interval [CI] 1.22 to 5.00) and cardiac death or MI (hazard ratio [HR] 2.85, 95% CI 1.41 to 5.77), whereas the adjusted risk for diabetic patients not treated with insulin was not significantly different from patients without diabetes for target lesion revascularization (OR 1.32, 95% CI 0.66 to 2.62) or cardiac death or MI (HR 1.04, 95% CI 0.50 to 2.17). In conclusion, diabetes mellitus is associated with increased risk for target lesion revascularization and cardiac death or MI after receiving sirolimus-eluting stenting, and is significantly exaggerated by the requirement for insulin therapy.

Stent thrombosis after successful sirolimus-eluting stent implantation.

BACKGROUND: Stent thrombosis (ST) is a rare but devastating complication of coronary stent implantation, occurring in 0.5% to 1.9% of patients with bare metal stents. The incidence of ST with drug-eluting stents is less well studied, particularly among patients outside of clinical trials. METHODS AND RESULTS: The aim of this study was to evaluate the incidence and potential risk factors for ST in patients receiving sirolimus-eluting stents (SES) in the "real world" after commercial release in the United States in April 2003. All 652 patients who underwent SES implantation (776 lesions treated) at our institution between April and October 2003 were followed up prospectively after the procedure (median follow-up 100 days). During that period, 7 patients (1.1%, 95% CI 0.4% to 2.2%) developed ST within a range of 2 to 13 days, and 1 patient had an ST-elevation myocardial infarction on day 39 with evidence of thrombus within the SES at angiography. Patients with an ST had significantly smaller final nominal balloon diameters (2.75 versus 3.00 mm, P=0.04), and in 4 (57%) of the 7 patients with ST versus 1.7% of patients without ST (P<0.001), antiplatelet therapy had been discontinued after the procedure. Among the ST patients, 1 died and 5 had myocardial infarctions. CONCLUSIONS: In this single-center experience, the incidence of ST after SES implantation was approximately 1%, which is within the expected range of bare metal stents. The discontinuation of antiplatelet therapy was strongly associated with the development of ST in this patient population.

Lack of early defibrillation capability and automated external defibrillators in nursing homes.

OBJECTIVE: To determine the availability of early defibrillation and automated external defibrillators in nursing homes in selected cities. DESIGN: A standardized telephone survey was conducted of all skilled nursing facilities to characterize early defibrillation capabilities. SETTING: The study involved nursing homes in Philadelphia, Omaha, Seattle, and Boston. PARTICIPANTS: All skilled nursing facilities not physically attached to hospitals in the selected cities based on listings from the Centers for Medicare and Medicaid Services as of January 2004. MEASUREMENTS: Each site was queried as to whether or not they had an automated external defibrillator (AED), if they were physically freestanding facilities, if a manual defibrillator was present, and if staff were present 24 hours a day to use the defibrillator. Early defibrillation was defined as the presence of either a manual defibrillator or AED in addition to 24-hour trained staff availability. RESULTS: There were 126 nursing homes identified from the Medicare listing and 81% (102) responded to our phone survey. After exclusion of non-freestanding facilities, 90 nursing homes (71.4%) were available for analysis. Overall, 16.7% (95% CI 8.8-24.5) of nursing homes reported early defibrillation capabilities via manual defibrillator or AEDs; 6.7% (95% CI 1.4-11.9) of nursing homes reported AEDs; 10.0% (95% CI 3.7-16.3) of nursing homes reported manual defibrillators. Nursing homes in Seattle had a higher rate of early defibrillation capability than the other 3 cities. CONCLUSION: Despite the fact that nursing homes have been identified as locations with multiple cardiac arrests, the early defibrillation capabilities and prevalence of AEDs in this setting remains low. AEDs may play a role in improving survival from cardiac arrest in nursing homes. The placement of AEDs in nursing homes needs further consideration and study.