Symptom onset-to-balloon time and mortality in the first seven years after STEMI treated with primary percutaneous coronary intervention.

OBJECTIVE

To evaluate the consequence of treatment delay of primary percutaneous coronary intervention (PPCI) on long-term survival.

BACKGROUND

Network organisation based on early recognition, shortening prehospital time delays and procedural delays is the cornerstone of optimal clinical results in the acute phase of ST-segment elevation myocardial infarction (STEMI). Nevertheless, the evidence of a relationship between symptom onset-to-balloon time and mortality is weak, and few long-term data are available. SETTING AND MEASURES: In this single-centre observational follow-up study, we evaluated the long-term survival of 790 consecutive STEMI patients (mean age 68 ± 13 years; 73% males) undergoing PPCI ≤ 12 h from symptom onset, or 12-36 h in the case of persistence of symptoms or hemodynamic instability.

RESULTS

The median (IQR) treatment delay, defined as the time from symptom onset to reperfusion, was 180 min (120;310), fairly balanced between patient delay (80 min (40;140)) and system delay (80 min (60-114)). Patients with a treatment delay <180 min displayed lower mortality at 1, 3, 5 and 7 years (12%, 17%, 22% and 26%, respectively) than those with a treatment delay >180 min (15%, 24%, 28% and 37%, respectively). The HR was 0.7 (95% CI 0.5 to 0.9). On univariate and stepwise multiple regression analysis, field triage and transportation (p=0.0001), shorter distance from hospital (p=0.02) and male gender (p=0.02), but not clinical variables, were independent predictors of shorter treatment delay.

CONCLUSIONS

Shorter symptom onset-to-balloon time predicts long-term lower mortality in STEMI patients treated with PPCI. Our findings emphasise the need to minimise any component of treatment delay.