Clinical Triggering of ST-segment Elevation Myocardial Infarction: Correlation with Coronary Artery Disease Extent

Background - Various physical, emotional and extrinsic triggers have been attributed to acute coronary syndrome. Whether a correlation can be drawn between identifiable ischemic triggers and the nature of coronary artery disease (CAD) still remain unclear. In the present study we evaluated the correlation between triggered versus non-triggered ischemic symptoms and the extent of CAD in patients with ST-segment elevation myocardial infarction (STEMI).

Methods - We conducted a retrospective, single center observational study including 1345 consecutive STEMI patients, treated with primary percutaneous coronary intervention (PCI). Acute physical and emotional triggers were identified in patients` historical data. Independent predictors of multi-vessel CAD were determined using a logistic regression model.

Results - A potential trigger was identified in 37% of patients. Physical exertion was found to be the most dominant trigger (67%) followed by psychological stress (15%) and acute illness (12%). Non-triggered STEMI patients tended to be older, and more likely to have co-morbidities. Non triggered STEMI patients showed a higher rate of multi-vessel CAD (73% vs. 30%, P<0.001). In a multivariable regression model non triggered symptoms emerged as an independent predictor of multi-vessel CAD (OR 8.33, 95% CI: 5.74-12.5, p=0.001). No specific trigger was found to predict independently the extent of CAD.

Conclusions - Symptoms onset without a recognizable trigger is associated with multi-vessel CAD in STEMI. Further studies will be required to elucidate the putative mechanisms underlying ischemic triggering.