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Background: Reoperative coronary artery bypass grafting (CABG) procedures are growing in importance due to the increasing number of patients requiring another bypass operation. Conventional redo-procedures are associated with an increased mortality and morbidity. To reduce risk, minimally invasive direct coronary artery bypass (MIDCAB) using the left internal mammary artery (LIMA) to the left anterior descending branch (LAD) may be preferable, when indicated, in selected patients. We report a series of patients who underwent this procedure for redo-CABG in our center., Methods: Since April 1997, 20 male patients who had undergone prior CABG using conventional procedure, were reoperated using the LIMA to LAD through a lateral minithoracotomy on the beating heart. Nineteen patients presented for a redo-CABG; one patient required a second-time redo-CABG. Two patients required concomitant PTCA of a second vessel as hybrid procedure. We reviewed these redo cases and studied their surgical results for mortality, morbidity, operation time, and hospital stay., Results: Mean operation time was 139 min (90-180). Four patients were extubated directly postoperatively; the others had a short period of ventilatory support. There was no myocardial infarction, no deaths or need of inotropic support postoperatively. No patient required re-exploration for bleeding. All patients could be mobilized and discharged early. At present, all patients are living and classified as CCS class I or II., Conclusions: Our results indicate that MIDCAB using IMA grafts for reoperation is a safe procedure with low risk for morbidity and mortality. This surgical technique is a useful alternative to conventional redo CABG in selected patients when complete revascularisation is not indicated.

Mitral valve ring abscess and ventricular pseudoaneurysm are rare complications of infective endocarditis. We describe the case of a 58-year-old man who was admitted to our hospital with sepsis caused by Staphylococcus aureus and in whom tricuspid and mitral valve endocarditis developed within 2 weeks. Despite widespread antibiotic therapy, the endocarditis proceeded to form a mitral valve ring abscess and a left ventricular pseudoaneurysm. The diagnosis was set by repeated multiplane transesophageal echocardiography and confirmed by heart surgery.

From September, 1986 through December, 1989, 121 patients underwent aortic valve replacement with the Mitroflow pericardial valve. There were 70 males (58%) and 51 females (42%), with an average age of 71 years (range 50-85 years). Reported here are the long-term results from these patients. Concomitant cardiac procedures were performed in addition to aortic valve replacement in 38 patients (31%); Coronary artery revascularization in 27 patients (22%); 4 patients (3%) had combination aortic/mitral valve replacement; mitral valve reconstruction in 4 patients (3%) and 3 patients (2%) had other additional procedures. Following surgery, standard postoperative examinations were performed every six month for 2 years; then yearly thereafter. At these times valvular function assessed echocardiographically. Current follow-up extends to 7 years (mean = 5 years) for surviving patients. Postoperative mortality for all observation period is as follows: Early deaths (> or =30 days postop) = 6 patients (5%), late death (>30 days) = 18 patients (15%). Valve-related causes of death included cerebral insult (thromboembolism) in two patients (one 10 months, other 15 months postoperatively). Postoperative valve-related morbidity included prosthetic endocarditis (1 patient) one year postoperatively; degenerative prosthetic failure (1 patient) 27 months postop; cusp tear (1 patient) with minimal hemodynamic changes after four years. In the patients with endocarditis and failure, a second successful operation corrected the problem. Also, in two patients antithrombolitic therapy related hemor-rhage occurred (one 9 months, the second 11 months postoperatively). This therapy was a result of atrial fibrillation, and we do not recommended it. In conclusion, we find that the Mitroflow pericardial heart valve gives adequate long-term results, especially in elderly patients with a small aortic ring, with very satisfactory quality of life.

Between 1978 and 1987, 1270 patients who survived single aortic or mitral valve replacement at the Rehabilitation Center in Bad Krozingen, Germany, underwent a comprehensive rehabilitation program. The preoperative diagnosis was isolated aortic stenosis in 425, isolated aortic regurgitation in 159, mixed aortic lesion in 211, isolated mitral stenosis in 208, isolated mitral insufficiency in 137 and mixed mitral lesion in 130 cases. Follow up examinations were carried out one and six months after surgery, and at yearly intervals thereafter. Exercise testing was performed with an electrically braked bicycle ergometer in the supine position, and the load was increased by 25 or 50 watts every two minutes until fatigue, severe angina, more than 0.3 mV ST-segment depression, or 80% of the age predicted maximum heart rate was achieved. Patients after aortic valve replacement had a better exercise performance one month after operation than did those after mitral valve replacement. Those with mitral stenosis showed more severe impairment of exercise tolerance than did the mitral insufficiency group. There was a steady increase in exercise tolerance between one and six months postoperatively, both in patients with aortic and those with mitral valve replacement, but the difference in performance between the two groups was still present (72% versus 57% of normal). The results of univariate and multivariate analyses showed that the preoperative employment status was the most important factor for postoperative return to work, followed by gender (male > female), exercise tolerance and valualar lesion (aortic > mitral).(ABSTRACT TRUNCATED AT 250 WORDS)

From November, 1971, to September, 1974, 1,179 patients received aortocoronary saphenous vein bypass grafts at the Cleveland Clinic Hospital. Segments of saphenous vein from each patient were sent for microscopical analysis. These vein segments were classified as normal or abnormal (phlebosclerotic). Four hundred ninety-six normal vein grafts in 295 patients were restudied and had a patency of 87.9%. One hundred forty-four abnormal vein grafts in 86 patients were restudied and showed 89.5% patency. This study suggests that histopathological identification of an abnormal (phlebosclerotic) vein segment does not constitute a determining factor as far as late patency is concerned in a vein segment that is not grossly sclerotic.

From 1978 to 1982 1 364 patients received an aorto-coronary vein graft, reoperations not included. Immediately after the operation the surgeon had to document the intraoperatively taken findings like diameter and quality of the coronary arteries, diameter and quality of the veins, quality of the aorta, bypass-flow according to a standardized protocol. 806 patients could be coronarographied 8 weeks after. The influence of intraoperative findings on the early occlusion of aorto-coronary vein grafts is discussed.

Rats were kept for 30 days in an O2-N2-mixture of gradually reduced O2 (18 leads to 6 Vol%) and constant CO2 (0.5 Vol percent). This induces a selective hypertrophy of the right ventricle and the ratio ventricular/body weight (g/kg) increased from 0.6 to 1.4 while it remained constant in the left heart. In the right and left ventricles of control animals the contents of myocardial ATP (4.0 muM/g) and of phosphocreatine (CP) (5.8 muM/g) were the same. These values were not significantly changed by hypertrophy. In the control animals, a single test-dose of isoproterenol (30 mg/kg), subcutaneously administered 2 hr before the heart was removed, caused a diminution of the ATP-content by 15 percent in the right ventricle and by 40 percent in the left. The CP-content was reduced by 40 percent on the right and by 50 percent on the left side. In the hypertrophied right ventricle, however, there was no major decrease in ATP and CP following the isoproterenol injection. In the nonhypertrophied left heart the response to isoproterenol was still detectable but much less than normal. As the chronotropic and hypotensive effects of isoproterenol were also lessened in the hypoxic animals it is concluded that a general reduction in the responsiveness to beta-adrenergic stimulation has occurred.

Concentrations of gentamicin in plasma, heart valves, subcutaneous tissue and muscle were determined in 38 patients undergoing open heart surgery. Gentamicin reached peak levels in plasma and tissue within 60 min after a 5 min intravenous bolus injection of 1.5 mg/kg body weight. Subcutaneous and muscle concentrations varied between 0.51 microgram/g and 2.1 microgram/g. Gentamicin peak concentrations in cardiac valvar tissue wre 3.6 mug/g between 2 and 5 hours after administration; gentamicin heart valve concentrations varied between 1.2 microgram/g and 1.59 microgram/g. Gentamicin tissue concentrations during open heart surgery are high enough to inhibit most Klebsiella/Enterobacter and Staphylococcus aureus and epidermidis strains. However Gentamicin heart valve concentrations do not exceed 1.5 microgram/g for more than 1 h, which may explain treatment failures of patients with endocarditis.