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This study was focused on the changes of high energy phosphates and tissue blood flow (TBF) in ischemia and reperfusion, of jaundiced rat liver. We ligated and cut the bile duct of male Wistar rats to induce jaundice. The rats were divided into two groups, BDL-4W which had ligation four weeks before examination and control which had no ligation. Two studies were performed; In study A, ischemia was induced by clamping portal vein and hepatic artery for 60 minutes. In study B, 15 minutes of ischemia was repeated four times with intervals of 10 minutes of reperfusion. A: 1) In BDL-4W, ATP was significantly lower than that in control at pre-ischemia and reperfusion. Recovery ratios (RR) of ATP in BDL-4W were significantly lower than those in control. 2) RR or TBF in BDL-4W were significantly lower than those in control. 3) In BDL-4W, xanthine was significantly higher than that in control at reperfusion. B: 4) There were no significant differences in the RR of ATP after reperfusion between two groups. 5) There were no significant differences in the RR of TBF between two groups. 6) There were no significant differences in xanthine after reperfusion between two groups. We concluded that intermittent brief ischemia was useful when 60 minutes of ischemia was required for the operation of jaundiced liver.

There are few reports on the assessment of the left ventricular function from left pressure-volume relationships intraoperatively in open heart surgery. LV Emax, Ea/Ees and EW/PVA efficiency were assessed intraoperatively by using a left ventricular conductance catheter in patients with aortocoronary bypass. After dobutamine administration (DOB, 10 micrograms/kg/min), LV Emax was increased by 33 +/- 23% during cardiopulmonary bypass (CPB) and 60 +/- 38% after weaning from CPB. Ea/Ees changed from 2.14 +/- 1.36 to 1.08 +/- 0.47 after weaning from CPB with dobutamine administration. EW/PVA efficiency changed from 52 +/- 12% to 66 +/- 10%. The change of LV Emax after dobutamine administration was correlated with the change of LV Emax after weaning from CPB and was correlated with Ea/Ees and EW/PVA efficiency after weaning from CPB. We concluded that measuring LV Emax before and after dobutamine administration during CPB is useful to assess left ventricular contraction clinically.

Left ventricular function and coronary sinus blood flow at rest and during exercise were evaluated in 27 patients after aortocoronary bypass surgery and in 13 normal subjects (G-C). Twenty patients (G-1) had successfully revascularized left anterior descending artery (LAD). In 7 patients (G-2), the revascularization for LAD was not complete. There was no difference among 3 groups in stroke work index (SWI), left ventricular end-diastolic pressure (LVEDP) and coronary sinus blood flow (CSF) at rest. SWI during exercise in G-2 (44.7 +/- 14.7 g. M/beat/m2) was significantly lower than that in G-1 and G-C (67.9 +/- 15.0, 77.2 +/- 17.0 g.M/beat/m2) (p less than 0.02, p less than 0.002). LVEDP during exercise in G-2 (32 +/- 6 mmHg) was significantly higher than that in G-1, G-C (17 +/- 7, 13 +/- 3 mmHg) (p less than 0.001, p less than 0.001). CSF during exercise in G-2 (160 +/- 64 ml/min) was significantly lower than that in G-1, G-C (357 +/- 79, 290 +/- 113 ml/min) (p less than 0.001, p less than 0.002). These data indicated that left ventricular function during exercise and coronary sinus blood flow reserve for exercise in patient with completely revascularized LAD was significantly better than that in patients with incompletely revascularized LAD.

As part of various defects in congenital heart disease, valvular lesions are frequently encountered and remain as one of the difficult subjects. Recent advances in the management of valvular lesions and late results of repair and replacement were reported. In congenital aortic stenosis, most of patients have obtained satisfactory results with valvotomy, but some required reoperation with valve replacement even during childhood. In supracristed VSD associated with aortic regurgitation, late recurrence of regurgitation was found in some, but 70% of the patients showed free of diastolic murmur after 10 years. In tetralogy of Fallot, definitive repair of pulmonary valve was performed in last 5 years with composite patch with patient's own pericardium to reduce postoperative pulmonary regurgitation. Recently, pericardium is treated with glutaraldehyde on the operating table to prevent late shrinkage. As external conduit, homograft aorta, which had been utilized previously, showed good late results comparable to xenograft in terms of free from reoperation. Xenograft has been frequently utilized without significant late obstruction so far. In atrioventricular canal, endocardial cushion prosthesis technique has been utilized satisfactory with recent modification of the wings made by glutaraldehyde treated patient's own pericardium as well as in tetralogy.

We studied cardiac rhythm in 167 patients with mitral stenosis following open mitral commissurotomy in the last 7 years. After surgery 76 patients (72%) out of 106 patients who presented atrial fibrillation before surgery were reverted back to sinus rhythm by D-C cardioversion. Forty-three patients (41%) maintained sinus rhythm at the time of discharge from hospital, and 30 patients (28%) maintained it for 2.5 years (average) after surgery. The actuarial maintenance rate of sinus rhythm was 50 + 11% 7 years after surgery in these 43 patients. Ninety-three% of the 30 patients who reverted to and maintained sinus rhythm improved to class I (New York Heart Association criteria), whereas 47% of the 78 patients who retained atrial fibrillation remained in class II or III after surgery. In 30 patients who reverted back to sinus rhythm and maintained it late postoperatively, the preoperative duration of atrial fibrillation was up to 5 years, and 35% of the patients had had atrial fibrillation for more than 1 year. Also, in 40% of these 30 patients, the preoperative cardiothoracic ratio was more than 60%. Therefore, in the patients who reverted to atrial fibrillation immediately after surgery, secondary D-C cardioversion should be performed under stable hemodynamic conditions 10 to 14 days after surgery, even if their preoperative duration of atrial fibrillation was more than 1 year or their preoperative cardiothoracic ratio was more than 60%.

We encountered one case of carotid body tumor. The patient was a 63-year-old man. The tumor was 5 cm X 6 cm in size, and it was strongly adhered to the carotid artery. Therefore, the tumor was removed with combined resection of the adherent lesion of the carotid artery. During the operation, we used a temporary external bypass method to prevent brain damage. The resected part of the carotid artery was reconstructed with saphenous vein graft. Angiogram one year after operation showed good patency of the graft. In Japanese literature, this is the second report of carotid body tumor removed by temporary bypass and the first report of use of a external bypass tube.

Left ventricular function and coronary sinus blood flow were evaluated in 7 patients with severe left ventricular dysfunction at rest before and after aortocoronary bypass surgery, and during exercise after surgery. Same evaluations were performed in 8 normal subject (G-C). Cardiac index (CI) at rest (2.09 +/- 0.55 l/min/m2) significantly increased after operation (2.94 +/- 0.59 l/min/m2) (p less than 0.02). There was no difference between CI during exercise after operation (5.94 +/- 1.51 l/min/m2) and that in G-C. Left ventricular end-diastolic pressure (LVEDP) at rest before operation (16 +/- 8 mmHg) was significantly higher than that in G-C (p less than 0.05). This difference disappeared after operation. LVEDP during exercise after operation (25 +/- 10 mmHg) was significantly higher than that in G-C (p less than 0.01). Coronary sinus blood flow (CSF) at rest (73 +/- 15 ml/min) significantly increased after operation (123 +/- 44 ml/min) (p less than 0.02). There was no difference between CSF during exercise after operation (282 +/- 99 ml/min) and that in G-C. These data indicated that the aortocoronary bypass surgery was effective on left ventricular function and coronary sinus blood flow in patients with severe left ventricular dysfunction.

In tetralogy of Fallot (TF) a new method of repair has been utilized since 1978. The method is transpulmonary and trans-atrial repair without or with minimal right ventriculotomy. Out of consecutive 81 patients, 79 patients underwent repair with this method with one operative death (operative mortality 1.3%). Postoperative hemodynamic evaluation revealed the better results in cardiac index, right ventricular endodiastolic volume and right ventricular ejection fraction. Also, pulmonary regurgitation has been reduced significantly compared to the conventional method with right ventriculotomy. The main criteria for total repair in TF is size of the pulmonary artery, and PA area Index (PA area/Normal R-PA area) over 0.20 is our minimal criteria to obtain postoperative right ventricular peak pressure ratio below 0.8. In double outlet right ventricle (DORV), operative mortality in last 5 years has improved to 19% (21 cases) from 68% of previous series. Six Taussig-Bing anomalies have undergone primary repair with 2 deaths. Various methods have been utilized including Kawashima 's method in 1 (0, op-death), Rastelli's method in 1(1), Hightower 's method in 1(0), and recently 2 patients had repair with Rastelli's operation with creating AP window to avoid subaortic obstruction. Also, Jatene operation (arterial switch) has been successfully performed in 8 month-old patient.

There were 14 patients with a mean age of 65 years (ranged from 47 to 77) who had severe coronary artery disease associated with cancer of other organs. Stomach cancer was in 8 patients, breast cancer in 2, lung cancer in 2, rectum cancer in 1, and esophagus cancer in 1. They were treated with sequence of coronary artery revascularization and surgery for cancer; 9 patients in a two-staged fashion and 5 recent patients in a simultaneous one. In the series of simultaneous procedure, A-C bypass was combined with left ventricular aneurysmectomy in one patient and closure of ASD in another. There was no cardiac complication in both series, but one death from the complication of surgery for cancer in the staged series. Three patients in the staged series could not help being postponed the surgery for cancer by slow recovery from A-C bypass. In conclusion, coronary artery revascularization should anticipate surgery for cancer and simultaneous combined procedures should be chosen when possible.

One hundred and eighty-two patients had been followed for 1 year or longer after aorto-coronary bypass grafting ( ACBG ). Four of them died in this follow-up period, one due to cardiac failure, 8 years postoperatively (p.o.), two due to malignant tumor and one due to an accident. About three quarters of patients improved p.o. into NYHA functional classification I, though no patients was in NYHA I preoperatively. More than 90% of patients with successful complete revascularization in left coronary artery and with a patent left anterior descending artery (LAD), improved into NYHA I. Four patients had reoperation due to the occluded graft to LAD in 4 months to 9 years p.o.. There was neither operative death nor late death 6 months to 4 years after reoperation. Patients with successful revascularization in left coronary artery had significant improvement in left ventricular function, but with unsuccessful one had less improvement. The patients with a history of myocardial infarction in successful revascularization in left coronary artery showed remarkable improvement of ejection fraction at rest and in elevation in LVEDP at exercise. These results show myocardial infarction causes irreversible functional and morphological damage and it could not be full recovered even after ACBG .

Some recently developed problems in cardiac surgery for acquired heart diseases, in our department, have been discussed in this paper. Ischemic heart disease (IHD): Indication for aortocoronary bypass grafting (ACBG) has been extended for the patients with poor left ventricular function. The number of the patients, who are found to have IHD before general surgery have been increased. Surgical treatments for these patients, five with malignant tumor, and two with aneurysm of the descending aorta, were performed 16 days to 4 months after ACBG without any operative death. In three patients with lesions of carotid arteries, blood flow of the carotid arteries was monitored with doppler echography, which was found useful for this purpose, during extracorporeal circulation. One hundred and four patients, over 40 years old, for valvular surgery, had coronary angiography at the cardiac catheterization between 1982-1983. Nine patients (8%) had significant IHD. They had ACBG and valvular surgery simultaneously. Valvular heart disease (VHD): Long-term results following aortic valve replacement have showed that 6 deaths were of cardiac origin. Five of them were with poor preoperative left ventricular function (ejection fraction: 0.35 or less, left ventricular endsystolic volume index: 200 ml/m2 or more) which might be indices for indication of surgical treatment for aortic regurgitation.