Sgarbossa Criteria are Highly Specific for Acute Myocardial Infarction with Pacemakers

In 1996 Sgarbossa reviewed 17 ventricular-paced electrocardiograms (ECGs) in acute myocardial infarction (AMI) for signs of ischemia. Several characteristics of the paced ECG were predictive of AMI. We sought to evaluate the criteria in ventricular-paced ECGs in an emergency department (ED) cohort.

Ventricular-paced ECGs in patients with elevated cardiac markers within 12 hours of the ED ECG and a diagnosis of AMI were identified retrospectively (n=57) and compared with a control group of patients with ventricular-paced ECGs and negative cardiac markers (n=99). A blinded board certified cardiologist reviewed all ECGs for Sgarbossa criteria. This study was approved by the institutional review board.

Application of Sgarbossa's criteria to the paced ECGs revealed the following: The sensitivity of "ST-segment elevation of 1 mm concordant with the QRS complex" was unable to be calculated as no ECG fit this criterion;For "ST-segment depression of 1 mm in lead V1, V2, or V3," the sensitivity was 19% (95% CI 11-31%), specificity 81% (95% CI 72-87%), with a likelihood ratio of 1.06 (0.63-1.64);For "ST-segment elevation >5mm discordant with the QRS complex," the sensitivity was 10% (95% CI 5-21%), specificity 99% (95% CI 93-99%), with a likelihood ratio of 5.2 (1.3 - 21).

In our review of ventricular-paced ECGs, the most clinically useful Sgarbossa criterion in identifying AMI was ST-segment elevation >5mm discordant with the QRS complex. This characteristic may prove helpful in identifying patients who may ultimately benefit from early aggressive AMI treatment strategies.