The authors experienced a case of fatal cerebellar, and brainstem infarction accompanying clamping of the left subclavian artery during operation for thoracic aortic aneurysm. Autopsy of this case revealed that right vertebral artery became markedly hypoplastic distal to the posteroinferior cere bellar artery, and left vertebral and basilar arteries were occluded by thrombus formation. These findings indicate that clamping of the dominant left subclavian artery is responsible for severe vertebrobasilar ischemia producing the fatal brain infarction. Since the occurrence of this devastating complication, we have performed pancerebral angiography and balloon occlusion test of the left subclavian artery in patients who might undergo proximal clamping of the aortic arch between the left carotid artery and the left subclavian artery during operations for thoracic aortic aneurysm. Selective perfusion of the left subclavian artery is then planned for those with abnormal vertebrobasilar communications producing neurological signs.

Left ventricular hypertrophy in patients with aortic valve disease has long been recognized as a significant risk factor for aortic valve replacement. Higher operative mortality in such patients has been attributed to poor myocardial preservation. In these patients improvement of left ventricular subendocardial blood flow during reperfusion seems to be mandatory to avoid subendocardial injury. Therefore, we attempted to increase subendocardial blood flow during reperfusion by terminal warm blood cardioplegia (TWBCP) followed by controlled aortic root reperfusion (CARR) in patients requiring isolated aortic valve replacement. The patients with TWBCP and CARR had a tendency towards severe left ventricular hypertrophy and more advanced NYHA function class compared to those with hypothermic cardioplegia alone. Nevertheless, the patients with TWBCP and CARR showed significantly better recovery of left ventricular function, i.e., spontaneous recovery of beating and higher cardiac index as well as left ventricular stroke work index, despite significantly less catecholamine support. These resuls suggest that TWBCP followed by CARR may offer significant benefits over unmodified reperfusion during aortic valve replacement for patients with severe left ventricular hypertrophy.