Vienna STEMI
The purpose of this study was to determine whether the implementation of therapeutic guidelines effectively improves in-hospital mortality after an acute ST-elevation myocardial infarction (STEMI) in a metropolitan area, in this case Vienna, Austria.
This was based on (1) the then-recommended time intervals, and (2) the varying clinical status of individuals presenting with myocardial infarction. For this purpose, uniformity among catheterisation laboratories was created by the implementation of a central triage network via the Viennese Ambulance System (VAS) in conjunction with recommendations to initiate TT, either in-hospital or before arrival at the hospital, if PPCI could not be offered in a timely fashion, particularly in patients who had experienced symptoms <2 hours. At the same time, a prospective registry was established for control and quality assurance purposes.
In 2002, Vienna, a city with 1.8 million inhabitants, had only 1 catheterisation laboratory (at the Department of Cardiology, University of Vienna) which offered a 24-hour PPCI service on a routine basis (on-call) for patients with acute STEMI. This situation was profoundly reorganised by the implementation of (1) central triage for STEMI patients by the Viennese Ambulance System (VAS); (2) a second catheterisation laboratory open at night (Monday to Friday) by use of a rotation principle between 4 non-academic hospitals (on weekends [Friday afternoon to Monday morning], only 1 catheterisation centre was active during this preliminary network); and (3) pre-hospital or in-hospital TT if acute PPCI was unlikely to be offered within the recommended time intervals.
CHANGES IN REPERFUSION STRATEGIES
![]() |
Implementation of guidelines resulted in an increased number of patients treated with one of the two reperfusion strategies (from 66% to 86.7%). Accordingly, the proportion of patients not receiving reperfusion therapy dropped from 34% to 13.4%. Management of patients via PPCI increased from 16% to almost 60%, whereas the use of TT decreased from 50% to 26.7% in the participating centres.
TREATMENT STRATEGIES SEGMENTED BY TIME-TO-TREATMENT
![]() |
Adapted from Kalla et al. Circulation 2006; 113: 2398–2405.
PCI could only be offered to 14.6% of patients within the first 2 hours after symptom onset, whereas thrombolysis was offered to 50.5% of patients within the first 2 hours after symptom onset.
In-hospital mortality rates were lowest in patients treated within 2 hours of symptom onset. Although the differences were not statistically significant, there was a trend in favour of thrombolysis over PCI (PCI 7.8%, thrombolysis 5.1%; p=0.37). However, as time from symptom onset increased, there appeared to be an increasing survival benefit with PCI over thrombolysis.
- Implementation of guidelines for the treatment of acute STEMI by the organisation of a cooperating network within a large metropolitan area was associated with a significant improvement in clinical outcomes.