高垣 昌巳

Left atrial plication (LAP) following Kawazoe's method was performed on eight patients with mitral valve stenosis associated with a giant left atrium. To investigate the effect of LAP particularly on left ventricular function, the preoperative and postoperative left ventricular function in these patients were compared. The data were also compared to that of the non-left atrial plication (non-LAP) group with left atrial dimension of 60 mm or over. In the LAP group, there were significant differences between preoperative and postoperative data in the following parameters; New York Heart Association (NYHA) class, cardiothoracic ratio, mean pulmonary arterial pressure (PAP), left ventricular end-diastolic pressure (LVEDP), left atrial dimension, stroke volume index, ejection fraction and cardiac index. On the contrary, in the non-LAP group, there were significant differences between preoperative and post-operative data in the following two factors; NYHA class and PAP. The size of the left atrium in the non-LAP group remained unchanged over the course of long-term follow-up. Despite severe clinical symptoms and severely reduced cardiac function of the patients in the LAP group, cardiac function in all patients improved satisfactorily. This suggests that left atrial plication has a considerably beneficial effect on left ventricular function, and therefore, may be recommended for patients with a giant left atrium.

Forty patients underwent coronary revascularization using bilateral internal thoracic artery (ITA) grafts between 1988 and 1992. A total of 111 coronary grafts were performed, or an average of 2.8 grafts per patient. Each patient received bilateral ITA grafts, and in 20 patients an additional 29 grafts were constructed with 18 autologous veins and 11 gastroepiploic arteries. The right ITA was grafted as a free graft in 20 patients. The ITA graft patency rate was 96 per cent (67/70) at the time of hospital discharge. The operative morbidity included 3 reoperations for bleeding, 1 perioperative myocardial infarction, 1 renal failure, 2 postcardiotomy shock, and 1 colon perforation. Two hospital deaths occurred; one due to colon perforation and the other due to postcardiotomy cardiogenic shock. One patient died of cerebral infarction 6 month after the operation. Thirty-four patients were in New York Heart Association functional class I, 2 were in class II and 1 was in class III. Cardiac function evaluated by echocardiography and scintigraphy showed significant improvement postoperatively. These data suggest that the use of bilateral ITA grafts is associated with an acceptable mortality and increases the versatility of arterial grafting.

A shortage of donor organs in clinical transplantation prompted us to study whether resuscitated dead hearts could be utilized for successful orthotopic heart transplantation. After 60 min of hypoxic cardiac arrest, one group of canine hearts was resuscitated (Res group, n = 6). The other group was harvested directly (Non-Res group, n = 6). In the Res group, cardiopulmonary bypass was utilized for resuscitation at 37 degrees C and the animals were then core-cooled to 15 degrees C. The hearts then were preserved in University of Wisconsin solution and orthotopically transplanted. Stable prostacyclin analogue (OP2507) and verapamil, a calcium antagonist, were added to the cardioplegia, and substrate-enriched warm blood cardioplegia and a hydroxy radical scavenger (EPC) were administered at the time of reperfusion of the transplanted heart. All animals in each group were successfully weaned from cardiopulmonary bypass with dopamine (5 micrograms/kg/min). Cardiac function without dopamine was better preserved in the Res group than the Non-Res group (Emax: 130.6 +/- 41.5% vs. 47.1 +/- 24.7%; mean +/- SD, as percent of postbrain death values, P < 0.01 by unpaired t-test). Cadaver hearts 60 min after anoxic arrest can be successfully re-animated and orthotopically engrafted. In addition, the core-cooling technique is useful. We believe this study serves as the key step in the clinical application of dead hearts to successful cardiac transplantation.