FFR-CT is extremely useful in detecting hemodynamically significant left-main coronary artery stenosis with right coronary artery hypoplasia: A case report

Left main coronary artery (LMCA) stenosis in patients with coronary artery disease (CAD) is associated with a significant increase in cardiac events, and determining its contribution to ischemia is essential. Currently, several noninvasive modalities are available for the ischemic assessment of CAD. In multi-vessel disease, including LMCA disease, the accuracy of myocardial perfusion scintigraphy (MPS) for detecting myocardial ischemia can be poor. Fractional flow reserve from computed tomography (FFR-CT) has emerged as a promising noninvasive modality that can provide functional myocardial ischemia information. Herein, we describe the case of a 50-year-old woman with type 2 diabetes who presented to the hospital due to intermittent chest pain on exertion. Coronary computed tomography angiography showed right coronary artery hypoplasia, 25 % stenosis in the LMCA, and 75 % stenosis in the left anterior descending. FFR-CT identified myocardial ischemia due to LMCA stenosis, but MPS did not. Invasive coronary angiography with conventional fractional flow reserve was mostly consistent with the results of FFR-CT. Fractional flow reserve from computed tomography (FFR-CT), which is a novel noninvasive method, can provide absolute, not relative, functional myocardial ischemia information by applying computational fluid dynamics to coronary computed tomography angiography on a lesion-by-lesion basis. FFR-CT can be extremely useful in detecting patients with left main coronary artery stenosis with right coronary artery hypoplasia.