[Incidence of use of various myocardial infarct treatments in 2 Swiss regions]

Trends in hospital discharges, management and in-hospital mortality from acute myocardial infarction in Switzerland between 1998 and 2008

Background

Since the late nineties, no study has assessed the trends in management and in-hospital outcome of acute myocardial infarction (AMI) in Switzerland. Our objective was to fill this gap.

Methods

Swiss hospital discharge database for years 1998 to 2008. AMI was defined as a primary discharge diagnosis code I21 according to the ICD10 classification. Invasive treatments and overall in-hospital mortality were assessed.

Results

Overall, 102,729 hospital discharges with a diagnosis of AMI were analyzed. The percentage of hospitalizations with a stay in an Intensive Care Unit decreased from 38.0% in 1998 to 36.2% in 2008 (p for trend < 0.001). Percutaneous revascularizations increased from 6.0% to 39.9% (p for trend < 0.001). Bare stents rose from 1.3% to 16.6% (p for trend < 0.001). Drug eluting stents appeared in 2004 and increased to 23.5% in 2008 (p for trend < 0.001). Coronary artery bypass graft increased from 1.0% to 3.0% (p for trend < 0.001). Circulatory assistance increased from 0.2% to 1.7% (p for trend < 0.001). Among patients managed in a single hospital (not transferred), seven-day and total in-hospital mortality decreased from 8.0% to 7.0% (p for trend < 0.01) and from 11.2% to 10.1%, respectively. These changes were no longer significant after multivariate adjustment for age, gender, region, revascularization procedures and transfer type. After multivariate adjustment, differing trends in revascularization procedures and in in-hospital mortality were found according to the geographical region considered.

Conclusion

In Switzerland, a steep rise in hospital discharges and in revascularization procedures for AMI occurred between 1998 and 2008. The increase in revascularization procedures could explain the decrease in in-hospital mortality rates.

Time trends in the treatment of acute myocardial infarction in Switzerland from 1986 to 1993: do they reflect the advances in scientific evidence from clinical trials?

Three acute coronary care surveys (1986, 1990, and 1993) were conducted in the Swiss region of Vaud-Fribourg on all men aged 25 to 64 years hospitalized for a definite myocardial infarction (218, 224, and 167 cases). Nearly all patients received anticoagulants and nitrates. The proportion of patients treated increased significantly, between 1986 and 1990, for antiplatelet drugs (from 51% to 96%) and thrombolytics (from 9% to 44%) and, between 1990 and 1993, for beta-blockers (from 57% to 78%) and angiotensin-converting enzyme inhibitors (from 26% to 43%). The use of calcium antagonists and antiarrhythmics dropped over time. Coronary arteriography and angioplasty were increasingly performed (53% and 18% in 1993), although progressively postponed in-hospital stay. The observed trends reflect a rapid translation of clinical trials into medical practice. However the use of thrombolytics could be raised further by shortening the hospitalization delay (median: 3 hours in 1993) and door-to-needle time (median: 47 minutes) which remained stable over time.