Clinical utility of estimated glomerular filtration rate in patients undergoing gated SPECT

Background  Chronic kidney disease is a major risk factor for coronary artery disease (CAD). The aim of the study was to examine the association between estimated glomerular filtration rate (GFR), presence of CAD, and prognosis in patients with reversible perfusion defects at gated single-photon emission computed tomography (g-SPECT). Methods  Six hundred fifty-eight subjects who had undergone stress/rest g-SPECT for evaluation of myocardial ischemia were divided into two groups according to the presence of CAD, defined by a 70% diameter stenosis in at least one major vessel or principal side branch at coronary angiography. Results  GFR was lower in patients with CAD and after adjusting for several clinical characteristics through multivariate logistic regression analysis, reduced (<60 mL/min/1.73 m²) GFR remained a significant predictor of CAD (HR 1.80, 95% CI 1.04 to 3.12, P = .036). In addition, reduced GFR was associated with a greater extent of myocardial ischemia, assessed through the summed difference score, as well as with an increase in both total and cardiac mortality. Conclusions  In patients with a positive g-SPECT scan, GFR is an accurate marker of CAD and is directly correlated to the extent of myocardial ischemia. Furthermore, reduced GFR had an adverse impact on survival in this particular population.