Selvester QRS score and total perfusion deficit calculated by quantitative gated single-photon emission computed tomography in patients with prior anterior myocardial infarction in the coronary intervention era.

Abstract

Selvester QRS scoring system has an advantage of being inexpensive and easily accessible for estimating myocardial infarct (MI) size. We assessed the correlation and agreement between QRS score and total perfusion deficit (TPD) calculated by quantitative gated single-photon emission computed tomography (QGS) in patients with prior anterior MI undergoing coronary intervention. Sixty-six patients with prior anterior MI and 66 age- and sex-matched control subjects were enrolled. QRS score was obtained using a 50-criteria and 31-point system. QRS score was significantly higher in patients with prior anterior MI than control subjects (12.8±8.9 vs 1.1±2.7%, p<0.001). In overall patients (n=132), QRS score was correlated well with TPD (r=0.81, p<0.001). This good correlation was found even in patients with TPD ≤40% (n=126) or in patients with TPD ≤30% (n=117). In overall patients, MI size estimated by QRS score was 7.0±8.8%, which was significantly smaller than TPD, 11.4±14.0% (p<0.001). Bland-Altman plot showed that there was an increasing difference between QRS score and TPD with increasing MI size. When Blant-Altman plots were applied to patients with TPD ≤40% and further in patients with TPD ≤30%, the difference between QRS score and TPD became smaller, and the agreement became better. In overall patients, QRS score was correlated well with QGS measurements, such as end-diastolic volume (r=0.62, p<0.001), end-systolic volume (r=0.67, p<0.001), or ejection fraction (r=-0.73, p<0.001). Our results suggest that QRS score reflects TPD well in patients with prior anterior MI, whose TPD is less than approximately 30% even in the coronary intervention era.