AMI in (bi)ventricular pacing – do not discard the ECG

BACKGROUND: There is a growing number of patients with ventricular paced rhythm, who present to the emergency department with chest pain. The diagnosis of ST-segment elevation myocardial infarction (STEMI) and subsequent percutaneous coronary intervention (PCI) is often postponed, as the 12 leads-electrocardiogram (ECG) is discarded as not interpretable. There is a growing body of literature that suggests that Smith-modified Sgarbossa criteria can be applied for the diagnosis of STEMI in patients with paced rhythms. These criteria were originally developed for the interpretation of ECGs in patients with a left bundle branch block (LBBB) and chest pain, but have been expanded to paced ECGs. METHODOLOGY: We present three case reports with chest pain and right ventricular or biventricular pacing. FINDINGS: In all three cases, the Smith-modified Sgarbossa was positive and the diagnosis of STEMI could have been made early on. IMPLICATIONS: It remains important to look for ST-segment deviations and to compare the symptomatic ECG with previous asymptomatic ECGs. As the number of patients with potential acute myocardial infarction (AMI) and paced rhythms is likely to rise in the future, these criteria should be known to emergency physicians and cardiologists.