The aim of this study was to evaluate short- and long-term outcome prior to and after the introduction of a more intensified treatment in the ambulance of patients with acute severe heart failure. Consecutive patients with acute severe heart failure transported by the mobile coronary care unit (MCCU) in the community of Göteborg prior to and after the introduction of an intensified treatment (nitroglycerine, continuous positive airway pressure (CPAP) and furosemide). One hundred and fifty-eight patients were evaluated during each period. The median age was 77 and 76.5 years, respectively, and 52% and 42% were women. The proportion of patients given nitroglycerine in the ambulance was 4% and 68% in the two periods; the proportion of patients treated with furosemide was 13% and 84%, respectively. CPAP was used in less than 1% during period 1 and in 91% during period 2. On admission of the ambulance 60% had fulminant pulmonary oedema during period 1 versus 78% during period 2 (p<0.0001). On admission to hospital the opposite was found, 93% during period 1 versus 76% during period 2 (p<0.0001). The median serum creatinine kinase (CK-MB) maximum activity was 13 microkat/l during period 1 and 8 microkat/l during period 2 (p = 0.007). However, the mortality during the first year remained high during both periods (39.2% and 35.8%, p = 0.64). It is concluded that a more intensive treatment in the ambulance of patients with acute severe heart failure seems to have resulted in an improvement in symptoms during transport and less myocardial damage. However, no significant improvement in long-term mortality was observed.