Simplified normal limits and automated quantitative assessment for attenuation-corrected myocardial perfusion SPECT

We aimed to compare normal limits and the detection of coronary artery disease (CAD) with attenuation-corrected (AC) and non-attenuation-corrected (NC) myocardial perfusion single photon emission computed tomography (MPS) by use of a recently improved automated quantification technique.

We acquired 415 rest/stress technetium 99m MPS studies on a Vertex dual-detector camera with a gadolinium 153 line source (Vantage Pro). Gender-specific NC, AC, and gender-combined AC normal limits were created from rest/stress images of 50 women and 50 men with a low likelihood of CAD (< 5%) and a median body mass index (BMI) of 30 kg/m2 in each gender group. BMI-specific normal limits (< 30 kg/m2 and > or = 30 kg/m2) were also compared. Total perfusion deficit and 17-segment summed scores in 174 patients were compared with angiography, and normalcy rates were established from 141 studies of low-likelihood patients. There were no differences between low-BMI and high-BMI normal limits for AC or NC studies. Male and female normal limits differed in 12 of 17 segments for NC stress studies and in 3 of 17 segments for AC stress studies (P < .01). The sensitivity, specificity, and normalcy rates for stenoses with 70% narrowing or greater were 89%, 73%, and 91%, respectively, for NC studies and 87%, 80%, and 95%, respectively, for AC studies (P = not significant).

Automated detection of CAD by AC and NC MPS demonstrated similar sensitivity, specificity, and normalcy rates. Some gender differences were noted for AC normal limits.