Valve Replacement in Children / 대한흉부외과학회지

BACKGROUND: Thirty children ranging from 3 to 15 years of age underwent cardiac valve replacement at Dongsan Medical Center from 1982 to 1997. MATERIAL AND METHOD: There were 16 boys and 14 girls. The mean age was 12.1. The underlying pathological cause for valve replacement was congenital heart disease in 17 children and acquired heart disease in 13. The valve replaced was mitral in 15 children, aortic in 11, tricuspid in 3, and combined aortic and mitral in 1. Twenty-one mechanical and 10 tissue valves were placed: primary mechanical valve have been utilized since 1985. Eight of ten patients with tissue valves have had successful second valve replacements 4 to 11 years after the initial operation. RESULT: The operative mortality was 6.7%, but mortality was higher among patients less than 5 years of age and patients who had previous cardiac operations. Of the 28 operative survivors, 4 patients were lost to follow-up: the remaining patients were observed for a total of 2091 patient/months(mean 74.7 months, maximum 187 months). There was one late death from dilated cardiomyopathy after mitral valve replacement in 7 year-old patient with atrioventricular septal defect. After the operation, all patients with mechanical valves were placed on a strict anticoagulant regimen with Coumadin. The actuarial survival rate was 96% at the end of the follow-up. No instance of thromboembolism or major bleeding were observed in the survivors. CONCLUSION: These results indicate that valve replacement can be performed with low mortality in children, and with satisfactory long-term survival.

Supra-Arterial Myotomy without Cardiopulmonary Bypass for Myocardial Bridging: One case report / 대한흉부외과학회지

Systolic coronary arterial narrowing, secondary to myocardial bridging which is capable of producing chest pain, myocardial infarction and ventricular fibrillation is a known but an uncommon entity. A supra-arterial myotomy in a case of myocardial bridge causing medication-refractory angina is described. Under the partial sternotomy incision, we performed a supra-arterial myotomy in the left anterior descending coronary artery without cardiopulmonary bypass. The postoperative course was uneventful.

Surgical Treatment of Pectus Excavatum / 대한흉부외과학회지

The pectus excavatum is the most common deformity of chest wall. The most common cause of surgical correction is cosmetic problem. From January 1981 to July 1996, 24 patients had undergone surgery for pectus excavatum and they were corrected by Ravitch operation (n=4) or modified Wada operation (n=20) respectively. We analyzed each surgical cases according to age, sex, chief complaint, degree of deformity, EKG findings, complications and satisfaction degree of patient. In some cases, we measured Welch index preoperatively and postoperatively. The postoperative complications were wound infection in two, pneumothorax in two and reccurrence in one. The average value of Welch index was significantly improved from 5.86+/-0.51 preoperatively to 4.10+/-0.51 postoperatively (p<0.05). The results by Humphreys' criteria were satisfiable in 88% (excellent 71%, good 17%). The findings of this study suggest that surgical correction of pectus excavatum with modified Wada rocedure and submammary s in incision is effective method in physical and psychiatric aspect.

Effect of Modified Ultrafiltration on Pediatric Open Heart Surgery / 대한흉부외과학회지

Total body water is increased after cardiopulmonary bypass resulting in tissue edema and organ dysfunction. Ultrafiltration has been used to reduce this accumulation of water. We have carried out a prospective randomized study in 17 children undergoing open heart surgery, comparing modified ultrafiltration (MUF) with nonfiltered controls. MUF was carried out for about 10 minutes after completion of cardiopulmonary bypass to a hematocrit 36~42%. Blood loss, blood transfused, hemodynamics, and laboratory data were recorded for 24 hours postoperatively. The results were analyzed using Mann-Whitney U test, comparing controls (n=7) to ultrafiltered (n=10). There was no death in each group. The mean filtrate volume (ml/kg) was 42 (30~68). Blood loss (ml/kg/24hr) was 14.5 mean (4.0~26.6) in controls versus 12.1 mean (6.0~21.5) in MUF (p>0.05) ; blood transfused (ml/kg/24hr) was 9.4 mean (6.0~36.3) in controls versus 3.4 mean (0~11.4) in MUF (p<0.05). There was rise in arterial blood pressure during MUF. Percent rise of systolic blood pressure was 4.2 (0~11.7) in controls versus 19.8 (7.0~36.9) in MUF (P=0.001). Percent rise of diastolic blood pressure was 10.0 (1.6~20.8) in controls versus 30.6 (5.8~73.3) in MUF (p<0.05). Platelet count, fibrinogen, and oncotic pressure rose after MUF. No complications directly attributable to the ultrafiltration were observed. Conclusively, MUF is safe, effective means of removing body water and beneficial to hemodynamics.

Effects of Autotransfusion using Cell Saver in Open Heart Surgery / 대한흉부외과학회지

Homologous blood transfusion entails substantial risks, including allergic reactions, transmission diseases such as hepatitis, acquired immunodeficiency syndrome. Autotransfusion system is a common method of reducing the need for homologous blood transfusion during cardiac operation. Between July 1993 and July 1995, a series of 40 patients undergoing open heart surgery was selected to an autotransfusion group (n=20) or a control group (n=20). The cell saver system (AT1000, Electromedics, Englewood, CO, USA) was employed for autotransfusion. With this system, shed blood in operative field during cardiopulmonary bypass (CPB) and remained blood in cardiotomy reservior after CPB was aspirated by means of a locally heparinized collecting system. After centrifuge salvaged blood, the resulting red cell concentrate reinfused subsequently. The amounts of blood loss were 766.5+/-121.3 ml in cell saver group, 770.1+/-113.6 ml in control group, and there were no significant differences between two groups (P=NS). The amounts of blood transfused were 2.91+/-1.72 units in cell saver group, 4.82+/-1.72 units in control group. Composition of processed blood by cell saver was hemoglobin 17.4 gm%, hematocrit 56.4%, RBC 5,780,000/ul, WBC 9,900/ul, and platelet 33,000/ul. There was no complication related to cell saver. Conclusively, cell saver autotransfusion system is safe, effective method for reducing the homologous blood trasfusion in cardiac surgery.

Reoperations on Heart Valve Prostheses / 대한흉부외과학회지

BACKGROUND: All currently available mechanical and bioprosthetic valves are associated with various types of deterioration leading to dysfunction and/or valvular complications. Reoperation on prosthetic heart valves is increasingly under consideration for both clinical and prophylactic indications. This review was conducted to determine the factors affecting the risk of reoperation for prosthetic valve replacement. MATERIAL AND METHOD: From January 1985 to July 1996, 124 patients underwent reoperation on prosthetic heart valves, and 3 patients had a second valve reoperation. The causes of reoperation were prosthetic valve failure (96 cases, 77.4%), prosthetic valve thrombosis (16 cases, 12.9%), prosthetic valve endocarditis (7 cases, 5.6%) and paravalvular leak (5 cases, 4.1%). This article is based on the analysis of the experience with particular emphasis on the preoperative risks affecting the outcome of the reoperation. RESULT: Overall hospital mortality rate was 8.9% (11/124). Low cardiac output was the most common cause of death (70.6%). Left ventricular systolic dimension (p=0.001), New York Heart Association functional class IV (p=0.003) and serum creatinine level (p=0.007) were the independent risk factors, but age, sex and cardiothoracic ratio did not have any influence on the operative mortality. Follow-up period was ranged from 3 to 141 months (mean, 50.6 months). A late mortality rate was 1.8%. CONCLUSION: The surgical risk of reoperation on heart valve prostheses in the advanced NYHA class patients is higher, therefore reoperation is recommended before the hemodynamic impairment become severe.