Trends in door-to-balloon time and outcomes following primary percutaneous coronary intervention for ST-elevation myocardial infarction: an Australian perspective.

BACKGROUND

Guidelines for patients with ST-elevation myocardial infarction include a door-to-balloon time (DTBT) of ≤90 min for primary percutaneous coronary intervention.

AIM

The aim of this study was to assess temporal trends (2006-2010) in DTBT and determine if a reduction in DTBT was associated with improved clinical outcomes.

METHODS

We compared annual median DTBT in 1926 STEMI patients undergoing primary percutaneous coronary intervention from the Melbourne Interventional Group registry. ST-elevation myocardial infarction presenting >12 h and rescue percutaneous coronary intervention was excluded. Major adverse cardiac events were analysed according to DTBT (dichotomised as ≤90 min vs >90 min). A multivariable analysis for predictors of mortality (including DTBT) was performed.

RESULTS

Baseline demographics, clinical and procedural characteristics were similar in the STEMI cohort across the 5 years, apart from an increase in out-of-hospital cardiac arrest (3.6% in 2006 vs 9.4% in 2010, P < 0.0001) and cardiogenic shock (7.7-9.6%, P = 0.07). The median DTBT (interquartile range) was reduced from 95 (74-130) min in 2006 to 75 (51-100) min in 2010 (P < 0.01). In this period, the proportion of patients achieving a DTBT of ≤90 min increased from 45% to 67% (P < 0.01). Lower mortality and major adverse cardiac event rates were observed with DTBT ≤90 min (all P < 0.01). Multivariable analysis showed that a DTBT of ≤90 min was associated with improved clinical outcomes at 12 months (odds ratio 0.48; 95% confidence interval 0.33-0.73, P < 0.01).

CONCLUSION

There has been a decline in median DTBT in the Melbourne Interventional Group registry over 5 years. DTBT of ≤90 min is associated with improved clinical outcomes at 12 months.