What is the discordance between morphological findings on CCTA and physiological findings on S-MPI in patients with intermediate to high probability of CAD?
A normal stress myocardial perfusion imaging result does not reliably exclude severe obstructive coronary artery disease, including left main or 3-vessel disease, in patients with an intermediate to high probability of CAD.
BACKGROUND: The aim of this study was to determine the relationship between the morphological and physiological information of coronary CT angiography (CCTA) and stress myocardial perfusion imaging (S-MPI) from the standpoint of risk stratification of patients with intermediate to high probability of coronary artery disease (CAD). METHODS AND RESULTS: In total, 51 patients underwent both CCTA and S-MPI as sequential examinations. In each patient, the severity of coronary plaque and stenosis (>50%) and the presence of myocardial perfusion abnormalities were assessed and the prognostic information from the CCTA and S-MPI results was compared. In 30 patients with normal S-MPI, 3 (10%) had only completely normal coronaries and another 3 (10%) had non-obstructive CAD as observed on CCTA. The remaining 24 patients (80%) with normal S-MPI and all 21 patients with abnormal S-MPI study had obstructive CAD. High-risk CAD (defined as obstructive left main trunk (LMT) lesion or 3-vessel disease) was seen in 10 (33%) of 30 patients with normal S-MPI, although it was less frequent than in the 14 (67%) of 21 patients with abnormal S-MPI. CONCLUSIONS: A normal S-MPI result can reflect a wide range of coronary atherosclerosis types and severities and, to some extent, involves severe coronary atherosclerosis such as LMT lesion and 3-vessel disease in patients with an intermediate to high probability of CAD.
Kiriyama et al. (Sat,) studied this question.