Bronchocoronary Collateral Circulation

Abstract

A 47-year-old male patient with 3-vessel coronary artery disease underwent quadruple coronary artery bypass graft surgery (right internal mammary artery-right coronary artery [RIMA-RCA], left internal mammary artery-left anterior descending artery [LIMA-LAD], and radial artery-second posterolateral branch with jump anastomosis to the first posterolateral branch). Surgery was complicated by difficulties sustaining cardioplegia and backflow of blood through the coronary arteries despite cross-clamping of the aorta. Eleven months after surgery, the patient presented with recurrent signs of ischemia on an electrocardiogram during exercise. Invasive coronary angiography was subsequently performed, which demonstrated a normal LIMA graft to the distal LAD (chronic total occlusion of the proximal and mid LAD). However, the RIMA graft showed a string sign (severe stenosis), and the RCA showed an 80% ostial stenosis. The circumflex (CX) and the radial artery bypass graft could not be demonstrated angiographically. Subsequent balloon angioplasty and stenting of the ostial RCA stenosis were successfully performed (complete reconstitution of flow and lumen). Despite revascularization, the patient continued to demonstrate signs of myocardial ischemia during exercise …