Accessibility to coronary angiography and one-year survival after myocardial infarction

In-hospital mortality due to acute myocardial infarction. relevance of type of hospital and care provided. RECALCAR study

INTRODUCTION AND OBJECTIVES

To investigate the relationship between in-hospital mortality due to acute myocardial infarction and type of hospital, discharge service, and treatment provided.

METHODS

Retrospective analysis of 100 993 hospital discharges with a principal diagnosis of myocardial infarction in hospitals of the Spanish National Health Service. In-hospital mortality was adjusted for risk following the models of the Institute for Clinical Evaluative Sciences (Canada) and the Centers for Medicare & Medicaid Services (United States).

RESULTS

Hospital characteristics are relevant to explain the variation in the individual probability of dying from myocardial infarction (median odds ratio: 1.3561). The risk-adjusted in-hospital mortality in cluster 3 and especially in cluster 4 hospitals (500 beds to 1000 beds and medium-high complexity) was significantly lower than in hospitals with less than 200 beds. Cluster 5 (more than 1000 beds), which includes a diverse group of hospitals, had a higher mortality rate than clusters 3 and 4. The adjusted mortality in the groups with the best and worst outcomes was 6.74% (cluster 4) and 8.49% (cluster 1), respectively. Mortality was also lower when the cardiology unit was responsible for the discharge or when angioplasty had been performed.

CONCLUSIONS

The typology of the hospital, treatment in a cardiology unit, and percutaneous coronary intervention are significantly associated with the survival of a patient hospitalized for myocardial infarction. We recommend that the Spanish National Health Service establish health care networks that favor percutaneous coronary intervention and the participation of cardiology units in the management of patients with acute myocardial infarction.

Rationale and methodology of the impact of continuous positive airway pressure on patients with ACS and nonsleepy OSA: the ISAACC Trial

BACKGROUND

Obstructive sleep apnea (OSA) is common in acute coronary syndrome (ACS) and a possible cause of increased morbidity and mortality.

OBJECTIVES

The main objective is to determine in patients with ACS and OSA if CPAP treatment reduces the incidence of cardiovascular events (cardiovascular death, nonfatal myocardial infarction, nonfatal stroke, hospitalization for heart failure, and hospitalization for unstable angina or transient ischemic attack). The secondary objectives are to determine the prevalence of nonsleepy OSA in patients with ACS; assess the effect of CPAP on the incidence of newly diagnosed diabetes mellitus, symptoms, and quality of life; identify biomarkers of risk involved in cardiovascular complications in these patients; and conduct a cost-effectiveness analysis of diagnosis and treatment.

POPULATION AND METHODOLOGY

Multicenter, prospective, randomized and controlled study. Patients are admitted to the coronary care unit with diagnosis of ACS and without daytime sleepiness (Epworth Sleepiness Scale ≤10) at 15 teaching hospitals in Spain. All patients undergo a sleep study by cardiorespiratory polygraphy. Patients with an apnea-hypopnea index ≥15/hour will be randomized to treatment with CPAP (group 1, 632 patients) or conservative treatment (group 2, 632 patients). Patients with an apnea-hypopnea index <15/hour (group 3, 600 patients) will be followed as a reference group. Patients will be monitored at baseline (T0), 1 month (T1), 3 months (T2), 6 months (T3), 12 months (T4), and every 6 months thereafter (where applicable) during the follow-up period.

CONCLUSIONS

The ISAACC trial will contribute to evaluating the effect of CPAP treatment on cardiovascular events in patients with ACS and OSA.

Revascularization and cardioprotective drug treatment in myocardial infarction patients: how do they impact on patients' survival when delivered as usual care

Background

Randomized clinical trials showed the benefit of pharmacological and revascularization treatments in secondary prevention of myocardial infarction (MI), in selected population with highly controlled interventions. The objective of this study is to measure these treatments' impact on the cardiovascular (CV) mortality rate among patients receiving usual care in the province of Quebec.

Methods

The study population consisted of a "naturalistic" cohort of all patients ≥ 65 years old living in the Quebec province, who survived a MI (ICD-9: 410) in 1998. The studied dependant variable was time to death from a CV disease. Independent variables were revascularization procedure and cardioprotective drugs. Death from a non CV disease was also studied for comparison. Revascularization procedure was defined as percutaneous transluminal coronary angioplasty (PTCA) or coronary artery bypass graft (CABG). The exposure to cardioprotective drugs was defined as the number of cardioprotective drug classes (Acetylsalicylic Acid (ASA), Beta-Blockers, Angiotensin-Converting Enzyme (ACE) Inhibitors, Statins) claimed within the index period (first 30 days after the index hospitalization). Age, gender and a comorbidity index were used as covariates. Kaplan-Meier survival curves, Cox proportional hazard models, logistic regressions and regression trees were used.

Results

The study population totaled 5596 patients (3206 men; 2390 women). We observed 1128 deaths (20%) within two years following index hospitalization, of them 603 from CV disease. The CV survival rate at two years is much greater for patients with revascularization, regardless of pharmacological treatments. For patients without revascularization, the CV survival rate increases with the number of cardioprotective drug classes claimed. Finally, Cox proportional hazard models, regression tree and logistic regression analyses all revealed that the absence of revascularization and, to a lower extent, absence of cardioprotective drugs were major predictors for CV death, even after adjusting for age, gender and comorbidity.

Conclusion

Considering usual care management of MI in the province of Quebec in 1998, CV survival is positively correlated to the presence of a revascularization procedure and to the intensity of cardioprotective pharmacological treatment. These results are coherent with data from randomized control trials.