Association of computed tomography-derived myocardial mass with fractional flow reserve-verified ischemia or subsequent therapeutic strategy.

The aim of the present study was to examine the association of myocardial mass verified by computed tomography (CT) and invasive fractional flow reserve (FFR)-verified myocardial ischemia, or subsequent therapeutic strategy for the targeted vessels after FFR examination. We examined 333 vessels with intermediate stenoses in 297 patients (mean age 69.0 ± 9.5, 228 men) undergoing both coronary CT angiography and invasive FFR, and reviewed the therapeutic strategy after FFR. Of 333 vessels, FFR ≤ 0.80 was documented in 130 (39.0%). Myocardial volume supplied by the target vessel (MVT) was larger in those with FFR-verified ischemia than those without (53.4 ± 19.5 vs. 42.9 ± 22.2 cm3, P < 0.001). Addition of MVT to a model including patient characteristics (age, gender), visual assessment (≥ 70% stenosis, high-risk appearance), and quantitative CT vessel parameters [minimal lumen area (MLA), plaque burden at MLA, percent aggregate plaque volume] improved C-index (from 0.745 to 0.778, P = 0.020). Furthermore, of 130 vessels with FFR ≤ 0.80, myocardial volume exposed to ischemia (MVI) was larger in the vessels with early revascularization after FFR examination than those without (37.2 ± 20.0 vs. 26.8 ± 15.0 cm3, P = 0.003), and was independently associated with early revascularization [OR = 1.03, 95% confidence interval (1.02-1.11), P < 0.001]. Using an on-site CT workstation, MVT identified coronary arteries with FFR-verified ischemia easily and non-invasively, and MVI was associated with subsequent therapeutic strategy after FFR examinations.