Time to treatment and ST-segment resolution in high-risk patients with acute myocardial infarction transferred from community hospitals for coronary angioplasty after pharmacological treatment.

OBJECTIVE: To evaluate the impact of symptom-onset-to-balloon delay on ST-segment resolution (STR) in patients with acute myocardial infarction transferred from community hospitals for angioplasty after pharmacological treatment. The study design was prospective, single centre registry.

METHODS: Between October 2000 and December 2003, 330 consecutive patients aged < or =75 years with high-risk myocardial infarction were considered; 193 patients underwent primary percutaneous coronary intervention (PCI) (group P), whereas 137 patients were given pharmacological therapy and were immediately transferred to the hospital with PCI facilities (group F).

RESULTS: Compared with group P, group F showed a longer time to treatment (253 +/- 136 vs. 195 +/- 141 min; P < 0.0001) and a higher percentage of Thrombolysis In Myocardial Infarction flow grade 2-3 at pre-PCI angiography (107 [78.1%] vs. 48 [24.8%]; P < 0.0001). The rate of STR > or =70% was similar in groups P and F (121 [62.7%] vs. 94 [68.6%]; P = 0.41). Even after accounting for baseline variables, STR <70% was not significantly related to the transfer strategy (adjusted hazard ratio 0.94, 95% confidence interval 0.94-1.77; P = 0.8). Patients with incomplete STR showed a higher six-month mortality compared with patients with complete STR (10 [8.85%] vs. 6 [2.76%]; P = 0.027).

CONCLUSIONS: The STR index predicts survival in patients with ST-elevation myocardial infarction treated with angioplasty either directly or after pharmacological treatment and hospital transfer. Pharmacological facilitation seems to be able to counterbalance the negative consequences of the transfer-related time delay on myocardial reperfusion as evaluated by the STR index.