Diagnostic accuracy of 320-slice computed-tomography for detection of significant coronary artery stenosis in patients with various heart rates and heart rhythms compared with conventional coronary-angiography

PurposeTo evaluate the diagnostic accuracy of 320-slice CT for detection of significant coronary artery stenosis in patients with various heart rates (HR) and heart rhythms, including tachycardia and chronic atrial-fibrillation (CAF) compared with conventional-coronary-angiography (CAG).Materials and methodsOne-hundred-six consecutive patients underwent both 320-slice CT and CAG within 3 months (normal-sinus-rhythm [NSR] 91.5%, CAF 8.5%, mean HR 65 ± 15 beats/min). There were no cardiac events between the 2 procedures. Patients were divided in 2 groups: Group 1 (HR < 65 with NSR at CT scan, n = 62), and Group 2 (HR > 64 with NSR or heart rhythm irregularities at CT scan, n = 44). Patients with > 50% or > 75% luminal stenosis on CT were compared with those with > 50% or > 75% stenosis on CAG, respectively.ResultsIn a segment-by-segment analysis, in all patients, sensitivity, specificity, positive (PPV) and negative predictive value (NPV) of > 50% stenosis on CT for predicting > 50% stenosis on CAG were 69, 98, 78, and 97%, respectively, and those of > 75% stenosis on CT for predicting > 75% stenosis on CAG were 78, 98, 64, and 99%, respectively. Sensitivity, specificity, PPV, and NPV of > 50% and 75% stenosis on CT for predicting > 50% and > 75% stenosis, respectively, on CAG were comparable. Diagnostic accuracy was essentially the same in both groups.Conclusion320-slice CT had high diagnostic accuracy for the detection of significant coronary artery stenosis compared with CAG. Even though the numbers were small, patients with high HR or heart rhythm irregularities might have essentially equivalent results to those with low HR with NSR.