A Case Report of Myocardial Ischemia Improvement Despite Early Bypass Graft Occlusion: Efficiency of Physiological Reassessment

Patients with functional ischemia often do not complain of chest symptoms even in early occlusion after coronary artery bypass grafting (CABG). The clinical evidence indicating the necessity of revascularization for these patients is unclear. A 70-year-old man who underwent 3 stent implant procedures to treat repeated in-stent restenosis to the left anterior descending artery (LAD) felt effort-related chest pain. Coronary angiography revealed that the patient's jailed diagonal had severe stenosis with delay and the LAD had intermediate stenosis. The instantaneous wave-free ratio (iFR) value of the LAD equalled 0.75. The patient underwent sequential CABG, where the left internal mammary artery (LIMA) to the LAD and diagonal artery grafts were performed. Although his effort-related chest pain disappeared, coronary and bypass angiography did not show flow competition in the diagonal branch and early occlusion in the LIMA to LAD graft was confirmed. The physiological assessment of the LAD did not reveal myocardial ischemia (iFR = 0.89 and fractional flow reserve = 0.87). This case highlights the importance of physiological assessment to detect cases of early graft occlusion. Although the LAD was not perfused from the CABG, the iFR value improved dramatically and pharmacological therapy without revascularization was successful for this patient. < The patient underwent coronary artery bypass grafting due to ischemia in the left anterior descending artery and diagonal branch. However, myocardial ischemia in two coronary artery branches was sufficiently improved by only one coronary artery bypass in this case. Physiological reassessment for early occlusion after bypass surgery is recommended for patients with myocardial ischemia.>.