Ultrasonic integrated backscatter in early assessment of myocardial injury during open heart surgery.

OBJECTIVES: The recovery of cyclic variation of ultrasonic integrated backscatter in myocardial ischemia provides early assessment of myocardial injury and is useful in assessing myocardial injury during open heart surgery. METHODS: We studied 25 patients with valvular disease undergoing cardiac surgery--7 with aortic stenosis, 7 with aortic regurgitation, 6 with mitral stenosis, and 5 with mitral regurgitation. All underwent transesophageal echocardiography (before aortic cross-clamping: T-pre and 60 minutes after aortic declamping: T-60). The short-axis view at the papillary muscle level of the left ventricle was recorded and anterior areas were assessed. RESULTS: The magnitude of cyclic variation at T-pre and T-60 was 9.4 +/- 2.5 dB and 8.8 +/- 3.0 dB, and the ratio was 97 +/- 32%. Fractional shortening at T-pre and at T-60 was 27 +/- 7% and 20 +/- 9%, and the ratio was 79 +/- 44%. Recovery of magnitude was ahead of recovery of fractional shortening. The percent recovery of magnitude at T-60 did not correlate with aortic cross-clamping time (p = 0.91), postoperative peak creatine kinase-MB (p = 0.4), or catecholamine dosage (p = 0.13), but correlated with preoperative left ventricular mass index (p < 0.01). In patients with aortic stenosis, the percent recovery of magnitude at T-60 (66 +/- 4%) was significantly lower than in those with other types of valvular disease. CONCLUSIONS: The recovery of magnitude of cyclic variation of ultrasonic integrated backscatter provides early assessment of myocardial injury, particularly in severely hypertrophied hearts, during reperfusion after aortic declamping in open heart surgery.

Successful launch of cardiac transplantation in Japan. Osaka University Cardiac Transplant Program.

Cardiac transplantation has been established as a therapeutic strategy for patients with end-stage heart failure. In Japan, however, cardiac transplantation has not been performed since the first case in 1968, and even now, after legislation for the approval of brain death was passed in 1997, it is still not performed regularly. Following long and steady efforts to enlighten Japanese society about the concept of brain death and the importance of organ transplantation, the first cardiac transplantation under the new legislation was successfully performed at Osaka University Hospital on February 1999. The patient was 47-year-old male in the dilated phase of hypertrophic cardiomyopathy who had been supported with an implantable left ventricular assist device. This article briefly reviews the situation prior to the first case of cardiac transplantation under the new legislation and discusses the current status of the therapy in Japan.

Real time assessment of myocardial revascularization during coronary artery bypass surgery by means of ultrasonic integrated backscatter.

OBJECTIVE: The recovery of cyclic variation (CV) of ultrasonic integrated backscatter (IB) may provide a more sensitive predictor of the success of myocardial revascularization. This study was designed to elucidate the possibility of real time assessment of coronary artery bypass grafting (CABG) using CV of IB. METHODS: We studied 10 patients (61 +/- 4 years old) with the perfused areas by stenosed or occluded LAD without myocardial infarction. There were six ischemic dysfunctional areas, and four ischemic but non-dysfunctional areas. The CV of IB was measured before and just after extracorporeal circulation (ECC). Wall motion was analyzed by segmental wall thickening during systole at the same time of the IB analysis during CABG and at 3 weeks after CABG. Those 10 areas were completely revascularized. RESULTS: In the non-dysfunctional areas, wall thickening did not change and remained at normal values before and after ECC, and 3 weeks after CABG (31 +/- 3% 29 +/- 3% and 29 +/- 5%, respectively). The magnitude of CV of IB did not also change before and after ECC (8.0 +/- 1.6 dB and 7.8 +/- 1.3 dB). However, in the ischemic dysfunctional areas, while wall thickening did not change before and after ECC (21 +/- 5% and 20 +/- 5%), it increased and reached similar values as the non-dysfunctional regions at 3 weeks after CABG (26 +/- 7%, P < 0.01 vs. before and after ECC values). The magnitude of CV of IB increased even after ECC (3.71 +/- 0.4 dB vs. 7.4 +/- 3.5 dB, P < 0.05), and reached the same level as those in the non-dysfunctional areas. There was a significant relationship between wall thickening at 3 weeks after bypass grafting and magnitude of CV of IB after ECC (r = 0.67, P < 0.05). CONCLUSIONS: Improvement in wall motion was gradually attained after bypass grafting. On the contrary, an increase in the magnitude of CV of IB was obtained immediately after myocardial revascularization. Our data suggest that CV of ultrasonic IB method can provide close real time information regarding the effectiveness of bypass surgery.

[Experimental and clinical assessment of myocardial protective effect of a prostacyclin analogue (OP 41483)].

The beneficial effects of a stable prostacyclin analogue (PGI2-A), OP 41483 against myocardial ischemic injury were experimentally and clinically evaluated. In 31P-NMR study, the preischemic treatment with PGI2-A prevented myocardial ATP depletion of rat hearts which were subjected to 20 min global ischemia. In patients with congenital heart disease, the PGI2-A of 300 ng/ml was added to the glucose-insulin-potassium cardioplegia (PGI2-group), and this group was compared to control group without PGI2-A in terms of postoperative maximal leakage of CPK-MB (maxCPK-MB). In patients under 1 yr or patients over 1 yr with aortic cross clamp time exceeded 120 min, the maxCPK-MB was significantly (p < 0.05) reduced as compared to the control. This stable PGI2 analogue has shown significant myocardial protective effects experimentally and also in clinical setting.