ABSTRACT
Subclavian arterial aneurysms are relatively rare compared to aortic aneurysms. The common causes of subclavian arterial aneurysms are arteriosclerosis, non-specific inflammation, thoracic outlet syndrome, and trauma. A case of a subclavian arterial aneurysm is reported. The patient was a 57-year-old woman. She had no previous history of hypertension, infection and trauma. She underwent complete resection of the aneurysm and reconstruction of right subclavian artery. Exploration of the aneurysmal wall revealed circumferential ridge which caused stenosis of the right subclavian artery at the orifice of the aneurysm. It has been suggested that a subclavian arterial aneurysm developed as a result of abnormal development of the embryologic right fourth and distal sixth aortic arches.
ABSTRACT
Three-channeled aortic dissection of the ascending aorta is rare. A 38-year-old man was given a diagnosis of DeBakey type I aortic dissection with three-channel at the ascending aorta on a chest CT scan. Right axillar and left femoral artery and two-stage right atrial cannulas were used to institute cardiopulmonary bypass. Hemiarch replacement was performed. The open proximal anastomosis technique was used under deep hypothermic circulatory arrest and selective cerebral perfusion. This three-channeled aortic dissection was thought to be produced by DeBakey type II dissection first followed by a retrograde dissection of DeBakey type III b. Since obstruction of the brachiocephalic artery due to the expansion of the pseudolumen was found during rewarming, reconstruction of the brachiocephalic artery was necessary. The present case was treated successfully by right axillary artery perfusion and subsequent reconstruction of the brachiocephalic artery.
ABSTRACT
It is commonly believed that prosthetic valve implantation in actively infected patients is to be avoided. After normalization of C-reactive protein and white blood cell counts, and sterilization of blood cultures by treatment with antibiotics, we performed valvular surgery. We performed mitral valve repair in cases where the mitral valve lesion did not involve the annulus. From July 1992 to November 1996, 13 patients (mean age, 50 years) were treated surgically for infective endocarditis (IE) at Kansai Medical University. Twelve of the patients had native valve endocarditis (NVE), and 1 had prosthetic valve endocarditis (PVE). In 6 patients, the causative organisms were determined. These included: α-<i>Streptococcus</i> in 4 patients, <i>Enterococcus</i> in 1, and methicillin-resistant <i>Staphylococcus aureus</i> (MRSA) in 1. The affected valves were as follows: aortic valve alone in 4 patients, mitral valve alone in 6, aortic and mitral valves in 2, and a prosthetic aortic valve in 1. The PVE was due to a MRSA infection which occurred 9 months after aortic valve replacement. All patients were treated preoperatively for heart failure and the infection. The surgical procedures performed were: aortic valve replacement in 4 patients, mitral valve replacement in 3, mitral repair in 3, double valve replacement in 2, and re-aortic valve replacement in 1. There were no deaths or recurrences of IE in hospital or during follow-up to date. In all of the mitral valve repair cases, the mitral regurgitation on follow-up echocardiograms was grade I. Our results show that surgical treatment of IE after management of preoperative conditions can be successful. Furthermore, despite the absence of laboratory findings indicative of ongoing inflammation or infection, pathologic examination revealed active inflammatory reactions and organisms in 4 cases. In 1 patient, MRSA was culthued from an annular abscess that was resected intraoperatively. We suggest that cessation of antibiotic therapy be regarded with caution and suggest that the infected site must be resected surgically.
ABSTRACT
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.
ABSTRACT
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.