Between May in 1988 and October in 1990, simultaneous coronary artery bypass grafting (CABG) and valve surgery was performed in 14 patients. Nine patients received arterial graft conduit for CABG (AG group) and only saphenous vein graft (SVG) was used in 5 patients (SVG group). In AG group, mean age was 63.3 years and the number of distal anastomosis was 2.2/patient. In valve operation, valve replacement was performed in 5 and valve plasty was in 4, and the mean aortic cross clamping time was 116min. As AG, internal thoracic artery (ITA) was used in 8 and right gastroepiploic artery (RGEA) was in 4. Among them concomitant use of ITA and RGEA was in 3, and the use of SVG was in 5. In two patients, the AG pedicle did not reach to either left anterior descending or obtuse marginal artery and the SVG was used as a graft conduit. Between AG group and SVG group, there were no significances in the age and aortic cross clamping time. However, postoperative use of cathecholamin was in three (33%) in AG group and three (60%) in SVG group and there were significant differences between them. In AG group, there were no operative deaths and the late NYHA improved to class I in 4 and class II in 5. In simultaneous CABG with AG and valve surgery, the improvement of symptom was good and stable operative result was obtained, however, the length of the pedicled graft should be carefully considered for coronary anastomosis.

The operative results in case of aortic coarctation (CoA) were studied. Between June 1980 and June 1995, 37 children with CoA underwent surgical intervention during their first year of life in our institute. The aortic lesion was repaired by the subclavian flap (SCF) method in 27, direct anastomosis (DA) method in 7, grafting or other methods in 3 children, respectively. The mean follow up period was 7.4±5.3 years (6 months-13 years). Rate of re-stenosis of the aorta was 10% (2 in 20 children) after SCF method, 0% (0 in 7 children) after DA method. The stenotic lesion was successfully dilated by the percutaneous balloon reconstruction in one child. Perioperative mortality was 25% (1/4) in one-stage repair, while one-stage repair was successfully performed in the last three cases and 16.6% (3/18) in two-stage repair for CoA associated with ventricular septal defect (VSD). The mortality was 60% (6/10) of CoA associated with other complex anomalies. In conclusion, one-stage repair seems to be recommendable for the operation of CoA with VSD, and two-stage repair seems to be safe for CoA with complex anomalies.

We studied the effects of intermittent tepid blood cardioplegia on patients with prolonged aortic cross-clamping. Forty patients undergoing coronary artery bypass grafting with cross-clamp time of greater than 120 minutes were studied. The patients were divided into two groups according to the cardioplegic solutions, cold (4°C) crystalloid cardioplegia (Cold) and tepid (30°C) blood cardioplegia (Tepid). Cardiac function, myocardial enzyme and clinical outcomes were compared between the groups. Mean aortic cross-clamp time were 150±10 minutes in the Cold group and 149±4 minutes in the Tepid group. Recovery rate of spontaneous rhythm after cross-clamp removal and postoperative left ventricular stroke work index were significantly greater in the Tepid group than those in the Cold group. Duration of ventilation and ICU stay were significantly shorter and total release of CK-MB, requirements of dopamine during 48 hours after the operation and the incidence of low-output syndrome were significantly less in the Tepid group. There were no early deaths in the Tepid group versus three early deaths in the Cold group. In conclusion, intermittent tepid blood cardioplegia provided superior postoperative cardiac function and clinical results to conventional cold crystalloid cardioplegia, thus the technique appears to be safe for patients requiring prolonged aortic cross-clamping.

Perioperative changes in thyroid function and hemodynamic state were studied in 6 hypothyroid patients and 15 euthyroid patients who underwent coronary artery bypass grafting. Serum free T₃ and total T₃ concentrations declined significantly in hypothyroid patients after the surgery. Serum total T₃ concentration decreased significantly also in euthyroid patients, indicating the occurrence of“euthyroid sick syndrome”in this group. Hypothyroid patients resulted in significantly lower left ventricular stroke work index despite greater central venous pressure and pulmonary capillary wedge pressure, and greater requirements of dopamine and dobutamine compared with those in euthyroid patients. The results indicated poorer postoperative cardiac performance in hypothyroid patients. Serum free T₃ concentration after cardiopulmonary bypass demonstrated a significant positive correlation with left ventricular stroke work index measured simultaneously. Preoperative serum free T₃ concentration showed a significant negative correlation with the postoperative dopamine and dobutamine requirements. Therefore, the results suggest that free T₃ has inotropic effects and the concentration of this hormone can be a predictor for a incidence of postoperative low cardiac output. In conclusion, since hypothyroid patients undergoing coronary artery bypass grafting are prone to have low cardiac output status, careful perioperative management, including hormone replacement therapy, is required for the patients.

The effects of human atrial natriuretic peptide (HANP, carperitide) were studied in 21 patients undergoing mitral valve surgery. The patients were randomized to receive either no carperitide treatment (control group, n=10) or carperitide (HANP group, n=11). Their hemodynamic status, diuresis and renal function were assessed perioperatively. The HANP group received continuous intravenous infusion of carperitide for 3 hours at a rate of 0.05μg/kg/min 3 hours after cardiopulmonary bypass. The HANP group had significantly lower systemic vascular resistance and less temperature difference between the rectum and the sole, and significantly greater cardiac index compared with those in the control group during infusion of carperitide, suggesting the improvement of cardiac performance by reducing afterload. The HANP group also had greater urinary output during the administration of carperitide, suggesting the significant diuretic effect of the regimen. The results indicated that the administration of carperitide may be a viable alternative strategy for the management of patients with postoperative heart failure. However, since transient oliguria was observed in 2 hypovolemic patients after the discontinuation of carperitide, careful monitoring is required during and after the infusion of the regimen in such patients.

A 53 year-old male with mitral valve aneurysm was presented. This patient, who had no episodes of rheumatic fever, was admitted with complaints of general fatigue, dyspnea and continuing high fever. Echocardiographic examination showed an abnormal echo behind the anterior leaflet of mitral valve, protruding into the left atrium during systole. Angiogram showed the same abnormal change of mitral valve and mitral regurgitation (MR) and aortic regurgitation (AR). We diagnosed as mitral valve aneurysm with MR and AR due to infective endocarditis. At operation, it was revealed that the aortic valve was destroyed, resulting in severe AR, and the anterior leaflet of mitral valve was a large aneurysm itself. Both valves were replaced with St. Jude Medical valve prosthesis. Postoperative course was good and with no complications. In Japan, 21 cases of mitral valve aneurysm were reported. We discussed the clinical course and the operative procedure for mitral valve aneurysm in this report.

We studied possible factors to cause left ventricular rupture after mitral valve replacement and the prevention in eight patients of 1, 046 receiving mitral valve replacement between September, 1965 and August, 1991. The age at operation ranged from 43 to 67 years old (average 58 years old), and there were one man and seven women. According to the Treasure and Miller's classification, the type of rupture was type I in 5, type II in 2, and type III in 3. The onset time of rupture was immediately after cardiopulmonary bypass in 3 and at the time of chest closure in one. In four patients it occurred 11 hours, 14 hours, 18 hours and 25 hours after operation, respectively. In 8 patients, repair was performed with external closure under heart beating and in five patients with both internal and external closure during cardiac arrest under cardiopulmonary bypass. Two patients under cardiopulmonary bypass were successful for hemostasis, however, they died with low cardiac output syndrome, following to multiple organ failure 2 or 44 days after operation, respectively. The repair was not successful in 6 patients. In four patients the left ventricular rupture occurred immediately after hypertension and pathological findings showed severe myocardial degeneration of left ventricular muscle in all of them. These findings may suggest that hypertension after the operation is one of major factors to cause left ventricular rupture and thus the careful management of the systemic blood pressure after mitral valve replacement is effective to prevent the left ventricular rupture.

The results and surgical techniques were studied in 59 patients who had atherosclerotic lesions in the ascending aorta. Arterial grafting (AG) and sequential grafting for coronary artery bypass grafting (CABG) was used in as many as possible cases and the number of distal anastomoses with AG was 1.3/patient (internal thoracic artery (ITA), 56 anastomoses for 50 patients; gastroepiploic artery (GEA), 17; and inferior epigastric artery, 3). Calcification in the ascending aorta was noted in 26 patients and arterial cannulation was performed via the right axillary artery in 4 patients. Saphenous vein grafts were used for 51 patients and 30 of them required aortic reconstruction for proximal anastomosis. There were 2 hospital deaths (non-cardiac) and no neurological complications. It is difficult to perform CABG in the presence of atherosclerosis in the ascending aorta. However, the right axillary artery cannulation as the site of arterial cannulation and the use of sequential grafting, using ITA and GEA as the pedicled arterial conduits are useful to accomplish CABG in such patients. Neurological complication seems to be manufactured at a minimal level by cautious operative techniques.

The effects of milrinone, a phosphodiesterase III inhibitor, were studied in patients with heart failure following coronary artery bypass grafting. Twenty patients with heart failure (either a cardiac index of less than 2.0l/min/m² or a pulmonary capillary wedge pressure of greater than 12mmHg) were divided into two groups according to whether or not they received postoperative milrinone administration. The control group (n=10) received no milrinone treatment and the milrinone group (n=10) received intravenous milrinone infusion at a speed of 0.5μg/kg/min postoperatively. The hemodynamic measurements were made perioperatively and clinical results were accessed perioperatively. Within-group comparison revealed a marked (p<0.05) decrease in pulmonary capillary wedge pressure and systemic vascular resistance in the milrinone group. Cardiac indices were significantly (p<0.05) greater in the milrinone group than those in the control group and within-group comparison revealed a significant (p<0.05) increase in left ventricular stroke work index in the milrinone group. There was no significant difference in rate pressure product in between- and within-group comparison. The milrinone group had a significantly (p<0.05) lower temperature difference between the rectum and the sole, and significantly (p<0.05) less catecholamine requirements postoperatively. Milrinone was not associated with a significant increase in the prevalence of adverse effects. The results suggest that milrinone possesses positive inotropic and vasodilatory effects in patients with heart failure following coronary artery bypass grafting. In addition to catecholamines and vasodilators, milrinone may become a useful agent in the treatment of patients with postoperative heart failure.

Ventricular Septal Defect (VSD) is the most frequent cardiovascular anomaly. VSD causes pulmonary hypertension through stenotic changes in the pulmonary vasculature, and this progress depends on the size of defect and associated cardiovascular anomalies. Since surgical repair has been performed in childhood for patients without a tendency toward spontaneous closure of VSD, operations in elderly patients, especially those aged over 40, are rare. We report an elderly patient with VSD complicated with severe pulmonary hypertension who underwent surgical repair. A 66-year-old man was admitted to our hospital because of general fatigue, chest oppression and palpitations. The pulmonary to systemic pressure ratio was 0.66. The oxygen saturation stepped up at the right ventricle level. The pulmonary to systemic blood flow ratio was 2.9, shunt ratio was 71% and resistance ratio was 0.12. The VSD was 18mm in diameter at the perimembranous trabecula and was closed with a Dacron patch through a right atrium incision. The lung biopsy specimen revealed little occlusive pulmonary vascular disease, Grade I according to the Heath-Edwards criteria. The patient had an uneventful recovery.