Prehospital diagnosis and start of treatment reduces time delay and mortality in real-life patients with STEMI

Journal of Electrocardiology 38 (2005) 186 www.elsevier.com/locate/jelectrocard

Prehospital diagnosis and start of treatment reduces time delay and mortality in real-life patients with STEMI Erik Bjfrklunda, Ulf Stenestrandb, Johan Lindb7cka, Leif Svenssonc, Lars Wallentina, Bertil Lindahla and the RIKS-HIA Investigators a Department of Cardiology, University Hospital, Uppsala, Sweden Department of Cardiology, University Hospital, Linko¨ping, Sweden c Department of Cardiology, University Hospital, Stockholm, Sweden Received 10 June 2005; accepted 10 June 2005 b

1. Introduction Time to reperfusion remains a key modifiable determinant of mortality in ST-elevation myocardial infarction (STEMI). A prehospital vs hospital thrombolytic treatment strategy has been shown to reduce time to treatment and mortality in randomized trials and in a small registry. We therefore evaluated time from onset of symptom to thrombolysis and mortality in a large cohort of unselected STEMI patients according to prehospital or hospital thrombolysis.

2. Methods Prospective cohort study using data from the Swedish Register of Cardiac Intensive Care on patients admitted to the coronary care units of 75 Swedish hospitals in 2000 to 2003. Only patients younger than aged 80 years with a diagnosis of acute myocardial infarction and with acute reperfusion treatment were included. All patients with thrombolysis (n = 13 360) were used when evaluating symptom duration, whereas only patients with the first recorded acute myocardial infarction during the registration period were used when evaluating 30-day (n = 11 263) and 1-year mortality (in 2000-2002) (n = 9088). Mortality data were obtained from the Swedish National Cause of Death Register. Time delays (minutes) are expressed as median (25th-75th percentile).

0022-0736/$ – see front matter D 2005 Elsevier Inc. All rights reserved. doi:10.1016/j.jelectrocard.2005.06.032

3. Results

Start of symptom to thrombolysis 30-day mortality (%) 1-year mortality (%)

n/n

Prehospital thrombolysis

Hospital thrombolysis

P

1651/9150

114 (70-200)

b .001

1749/9514 1251/7837

5.3% 7%

170 (107-295) 7.6% 11%

.001 b .001

The population receiving prehospital thrombolysis was significantly younger and had fewer women, diabetes mellitus, previous myocardial infarction, heart failure, and stroke, and was less likely to have symptoms of heart failure and used less medication indicative of heart failure and ischemic heart disease. In multivariable analyses, after adjusting for a number of risk factors including the above and rescue angioplasty, a prehospital treatment strategy was associated with significantly lower 1-year mortality (OR 0.75, 95% CI 0.58-0.96). When only including ambulance transported patients in the model, the lower adjusted mortality in the prehospital-treated group was even more pronounced (OR 0.66, 95% CI 0.51-0.85). 4. Conclusion Prehospital diagnosis and treatment reduces time to thrombolysis by almost 1 hour and reduces adjusted longterm mortality in real-life patients. This approach is therefore recommended as one treatment alternative in acute STEMI.