There is an impression among cardiothoracic surgeons that the technique of profound hypothermic circulatory arrest (PHCA) is associated with an increased bleeding tendency compared to conventional bypass surgery. In addition to the recognized factors contributing to the hemorrhagic tendency seen in moderate hypothermic cardiopulmonary bypass (CPB), it is likely that the lower temperature utilized in PHCA may exacerbate platelet dysfunction. In this report, platelet counts and functions at the same cardiopulmonary bypass time were compared in human PHCA surgery (hypothermia group, n=16) and moderate hypothermic cardiopulmonary bypass surgery (control group, n=20). Mean platelet count corrected by hematocrit in the hypothermia group at 2h of CPB was significantly lower than in the control group (3.7×10⁴μl vs. 11.4×10⁴/μl, p<0.0001). In the hypothermia group, there were significant increases in the percentage of GMP-140 (P-selectin)-positive platelets (11.8% vs. 8.3%, p=0.0091) at 1h of CPB, and also in microparticles (24.8% vs. 10.5%, p<0.0001) and aggregated platelets (3.4% vs. 1.4%, p=0.0058) at 2h of CPB. Profound hypothermic circulatory arrest used in surgery for aortic arch aneurysm or dissection may cause irreversible platelet dysfunction and contribute to hemorrhagic tendency during the surgery. To minimize platelet dysfunction during CPB, the lowest blood temperature should be maintained above 15°C.

A 6-year-old boy who had been found to have hypertrophic obstructive cardiomyopathy presented with severely limited symptoms of heart failure due to progressive left ventricular outflow obstruction. Cardiac catheterization revealed the peak systolic pressure gradient of 87mmHg at left ventricular outflow, and systolic anterior motion of the anterior mitral leaflet with concomitant mitral regurgitation was observed by echocardiography. Transaortic septal myectomy was performed using transesophageal echocardiography guidance before, during and after surgery. Although the patient needed permanent pacemaker implantation for postoperative complete heart block, the procedure reduced the left ventricular outflow obstruction and relieved his symptoms.

A baby girl with a low birth weight was given a diagnosis of congenital bicuspid aortic stenosis and mitral valve prolapse. At the age of 40 days, she underwent balloon aortic valvotomy, but significant aortic regurgitation appeared afterwards. Another surgical intervention became necessary by the age of 20 months (weight, 5.7 kg), because of intractable heart failure mostly caused by exacerbated mitral regurgitation. We performed a leaflet extension valvuloplasty for the small bicuspid aortic valve using an autologous pericardium treated by glutaraldehyde. The mitral valve was replaced with an ATS-16AP valve. Although her postoperative course was complicated with mitral paravalvular leakage and poor left ventricular function, she was discharged from hospital 6 months post operatevely. Leaflet extension valvuloplasty is a surgical option for infants with a small aortic annulus, but the procedure could be the only solution in cases when Konno or Ross techniques are not suitable.

Thirty-nine years old woman had a severe renovascular hyper-tension with Takayasu's arteritis Her left renal artery stenosis was treated with percutaneous transluminal angioplasty (PTA) three times. Six months after the third PTA, the left renal artery was occluded, and left renal failure occurred. Aorto-renal bypass surgery with a prosthetic graft was performed. Blood pressure dropped to normal range, and left renal function began to recover. Although PTA is an effective method in the treatment of renovascular hypertension, an incidence of restenosis after PTA is higher in Takayasu's arteritis rather than atherosclerotic lesions. Five months after renal revascularization, hypertension recurred in this case. However the aorto-renal bypass graft was patent accompanied by no symptoms. This aorto-renal bypass surgery can be considered effective in this condition.

A cyanotic baby boy was given a diagnosis of single right ventricle, double outlet right ventricle, hypoplastic aortic arch, mitral atresia, atrial septal defect and pulmonary-ductus-descending aorta trunk. On day 4, extended aortic arch anastomosis and pulmonary artery banding were undertaken. At age 70 days, severe cyanosis and respiratory distress appeared and advanced rapidly. Angiography revealed critical subaortic stenosis and pulmonary hypertension, and the patient required urgent Damus-Kaye-Stansel anastomosis with concomitant right modified Blalock-Taussig shunt. Patients with single ventricle and hypoplastic aortic arch are a high-risk subgroup of progressive subaortic stenosis after initial pulmonary artery banding, and therefore need careful observation and may require early relief of subaortic stenosis.

Causative factors for thrombi formation in left atria of 38 patients with mitral stenosis who underwent mitral valve surgery (open mitral commissurotomy or mitral valve replacement) alone or in combination with other procedures were studied. There were 9 cases of left atrial thrombosis (LAT). Left atrial diameter was increased in LAT(+) group (6.1±1.6cm) compared with LAT(-) group (4.6±0.7cm). There was significant difference in the left atrial diameter between the two groups of patients (p<0.01). Cardiac output was decreased in LAT(+) group (3.04±0.74l/min) compared with LAT(-) group (3.99±1.07l/min). Cardiac output of LAT (-) group was significantly larger than that of LAT(+) group (p<0.05). Mean transition time of blood through left atrium (MTT_LA) was calculated using left atrial volume and cardiac output. In LAT (+) group, MTT_LA was significantly increased (6.2±3.9sec) compared with LAT(-) group (2.9±1.6sec). It is considered that, in mitral stenosis, prolongation of MTT_LA is one of the risk factors for thrombi formation in the left atrium.

This is a case report of a 57-year-old woman with high aortic occlusion (HAO) who had acute symptoms of severe ischemia of the lower extremities and the intrapelvic organs. Generally, HAO is a chronic ischemic disease of the lower extremities and the intrapelvic organs; therefore, acute HAO is relatively rare. Acute thrombotic occlusion of a major collateral artery might be the cause of acute HAO. Laser Doppler flowmetry of the sigmoid colon was useful to evaluate the ischemia of intrapelvic organs. Thrombectomy of the juxtarenal portion with the suprarenal aortic cross clamp was performed within four minutes, then the clamp was moved to the infrarenal portion. The remaining occluded aorta was replaced with a Y-shaped knitted Dacron graft. She had no symptoms after the surgery except renovascular hypertension. Seventy five percent stenosis of the right renal artery was exacerbated to 99%. Vascular clamping of the right renal artery might have been the cause of severe stenosis. Percutaneous transluminal renal angioplasty was successfully performed after the surgery. Aggressive renal artery reconstruction during surgery is recommended in cases with moderate or severe renal artery stenosis.

We performed surgical treatment for 21 patients of airway obstructions associated with congenital heart disease from December 1986 to March 1993. In all patients perioperative bronchoscopy demonstrated the cause and site of airway obstructions. Seven patients with corrective cardiac surgery (7/7), 7 with palliative cardiac surgery (7/10) and 2 with surgery for airway diseases (2/4) could be weaned from respirators following surgical treatment. Five patients died postoperatively. A respirator was required in 16 patients (76%) preoperatively. The suspension of pulmonary artery with intraoperative bronchoscopy was carried out in 6 patients. Five (5/6) were successfully extubated earlier postoperative day (mean 8.4 days), whereas only five in 10 patients without that procedure could be weaned from the respirator at a mean of 2 months. Identification of potential airway obstruction and early extubation is needed to reduce the mortality and morbidity caused by airway obstruction associated with congenital heart disease. Preoperative bronchoscopy is useful for diagnosis of airway obstructions and essential for decision making concerning surgical treatment. To early extubation in patients with marked airway obstructions, we recommend appropriate choice of the surgical procedure combined the suspension of pulmonary artery.

Seven patients with congenital heart defects suffered from multiple major hemorrhages from the lung after surgery and 5 of them died at 8 to 54 postoperative days because of respiratory insufficiency. In a patient with tetralogy of Fallot associated with pulmonary atresia, bleeding occured after the second shunt operation, presumably from rupture of bronchial collateral vessels. The clinical diagnoses of the other 6 patients were coarctation of the aorta (CoA) with common atrioventricular canal (CAVC) in 1, triple shunt in 1, persistent truncus arteriosus in 2, total anomalous pulmonary venous connection in 1 and CAVC in 1. Subclavian flap aortoplasty was performed without pulmonary artery banding in the patient with CoA and CAVC, whereas complete repair was performed in the other 5 patients. As these patients were associated with severe pulmonary hypertension preoperatively and 4 of them encountered pulmonary hypertensive crisis, the hemorrhage from the lung may be related to pre and postoperative high pressure of the pulmonary artery. Dilatation and rupture of the pulmonary capillary net was demonstrated in the patient with CoA and CAVC. These findings suggest the hypothesis that bleeding occurred due to rupture of the capillary net as a result of transmission of high pressure. Major bleeding from the lung is a rare but catastrophic complication after repair of congenital heart defects. As the treatment is difficult, early surgical intervention and treatment of postoperative pulmonary hypertension are important in complex lesions with severe pulmonary hypertension.

The incidence of ventricular subepicardial aneurysm following myocardial infarction is quite low. We report a case of subepicardial aneurysm that was diagnosed on postoperative pathohistologic examination. A 69-year-old man was admitted to our hospital because of left ventricular aneurysm following myocardial infarction. The patient had left main trunk disease, triple-vessel coronary artery desease and low output syndrome. Under cardiopulmonary bypass with the heart arrested, the aneurysm was resected and the defect was closed. The suture line was reinforced using Teflon felt and GRF glue. A saphenous vein graft was anastmosed to the left anterior descending artery. On pathohistologic examination, the wall of the aneurysm was found to be composed of fibrotic tissue, myocardial fibers, medium-sized pericardial arteries, epicardium and fibrin thrombi. We diagnosed this as subepicardial aneurysm.