No abstract

A coronary artery aneurysm is uncommon and frequently asymptomatic. This report presents a surgical case of a giant coronary artery aneurysm complicated by acute myocardial infarction. A 26-year-old man with sudden chest pain was referred to our hospital. Myocardial infarction was suspected, and emergency coronary angiography was performed. A giant coronary aneurysm was found in the mid-portion of the right coronary artery. The aneurysm, which was thrombosis-occluded, was successfully resected, and the right coronary artery was anastomosed in an end-to-end fashion. Although the strategy for treating a coronary artery aneurysm without myocardial ischemia remains controversial, surgical intervention should be considered in cases with a giant coronary artery aneurysm, even if asymptomatic, provided the surgical risk is low.

Atrionatriuretic peptide (ANP) is reported to be useful for attenuating myocardial ischemia-reperfusion injury and improving left ventricular function after reperfusion. However, ANP may be either ineffectual or harmful in cases where the myocardium has been chronically hypoxic since birth. This can be a result of the concomitant high levels of cyclic guanosine monophosphate (cGMP) produced within the myocardium. This study aimed to verify the validity of using ANP to improve left ventricular function after myocardial ischemia-reperfusion injury. For this purpose, a cyanotic congenital disease model that was developed using isolated rat hearts was used. Hearts were obtained from Sprague-Dawley rats that were housed from birth until 6 weeks of age either in a hypoxic environment with 13-14% FiO(2) (hypoxic group) or in ambient air (normoxic group). These hearts were subjected to 30min of normothermic global ischemia followed by 30min of reperfusion using the Langendorff technique. Left ventricular functional recovery in hearts administered ANP (0.1µM) into the reperfusion solution was compared with those hearts that were not administered ANP in both hypoxic (without ANP: n=6, with ANP: n=6, with ANP and HS-142-1[an antagonist of ANP]: n=6) and normoxic hearts (without ANP: n =6, with ANP: n=6). In the hypoxic hearts, ANP administration improved the percent recovery of the left ventricular developed pressure (76.3±9.2% without ANP vs. 86.9±6.7% with ANP), maximum first derivative of the left ventricular pressure (82.4±1.1% without ANP vs. 95.8±6.5% with ANP), and heart rate (85.6±4.7% without ANP vs. 96.1±5.2% with ANP) after reperfusion. The improvement and recovery of these cardiac functions were closely related to significantly increased levels of postischemic cGMP release after ANP administration. The effect of ANP was blocked by HS-142-1. The improvements observed in the hypoxic group were similar to those found in the normoxic group. ANP administration during reperfusion improved left ventricular function after myocardial acute global ischemia-reperfusion equally in both the chronically hypoxic and age-matched normoxic groups.

Late upper extremity embolic complications of occluded axillofemoral bypass graft (AxFG) or occluded axillo- axillary bypass graft (AxAG) are not frequently noted. A patient presented with acute right upper extremity thromboembolism 2 years after an AxFG occlusion. Computed tomography (CT) findings revealed kinking and occlusion of the axillary artery at the anastomosis. Another patient presented with acute left upper extremity thromboembolism 2 years and 6 years after an AxAG occlusion. CT indicated a thrombus progressing from the occluded graft to the axillary artery. Surgical repair of the axillary artery was performed in both patients without any complications.

Chronic hypoxia from birth increased myocardial tolerance to ischemia-reperfusion injury with increased cGMP synthesis in the isolated heart model in rats.