NPPB and myocardial ischemia: Analyzed in terms of the severity or extent of myocardial ischemia detected in SPECT, there was a significant correlation between logarithmically transformed BNP and summed rest score (perfusion defect at rest) in patients (r = 0.249, P < .001) and those with positive SPECT (r = 0.309, P = .001) (Table 2).