Protein kinase C activation contributes to microvascular barrier dysfunction in the heart at early stages of diabetes.

The functional disturbance of microvasculature is recognized as an initiating mechanism that underlies the development of various diabetic complications. Although a causal relationship between microvascular leakage and tissue damage has been well documented in diabetic kidneys and eyes, there is a lack of information regarding the barrier function of coronary exchange vessels in the disease state. The aim of the present study was to evaluate the permeability property of coronary microvessels during the early development of experimental diabetes with a focus on the protein kinase C (PKC)-dependent signaling mechanism. The apparent permeability coefficient of albumin (Pa) was measured in isolated and perfused porcine coronary venules. The administration of high concentrations of D-glucose induced a dose-dependent increase in the Pa value, which was prevented by blockage of PKC with its selective inhibitors bisindolylmaleimide and Goe 6976. More importantly, an elevated basal permeability to albumin was observed in coronary venules at the early onset of streptozotocin-induced diabetes. The hyperpermeability was corrected with bisindolylmaleimide and the selective PKCbeta inhibitor hispidin. Concomitantly, protein kinase assay showed a high PKC activity in isolated diabetic venules. Immunoblot analysis of the diabetic heart revealed a significant subcellular translocation of PKCbetaII and PKCepsilon from the cytosol to the membrane, indicating that the specific activity of these isoforms was preferentially elevated. The results suggest that endothelial barrier dysfunction attributed to the activation of PKC occurs at the coronary exchange vessels in early diabetes.

Surgical treatment of leukemic involvement of the mitral valve.

A patient with severe mitral insufficiency due to infiltration of the valve and myocardium by leukemic lymphocytes is presented. Treatment was replacement of the valve with a prosthesis. The significance of this patient lies in the rarity of the clinical state and the novelty of treatment.

Migration of temporary epicardial pacer wire fragment retained after a cardiac operation.

Reported complications of retained temporary epicardial pacer wires after cardiac operations have been confined to infections. We report the migration of the retained fragment into the free peritoneal cavity after 6 years of stability in the precordium.

The electrical dose for direct ventricular defibrillation in man.

The threshold electrical energy for direct ventricular defibrillation was measured in 100 patients whose hypothermic hearts were fibrillated for cardiac operations. In 93 cases 10 joules or less was sufficient, and in 48 of these cases 5 joules or less defibrillated the ventricles. Because a shock of 10 joules defibrillated the heart of most of our patients, we recommend an initial shock of 5 to 10 joules rather than the 20 joules used more commonly. Until the safety margin between defibrillation threshold and damage threshold is established for direct defibrillation, use of shocks with adequate but not excessive strength may avoid unnecessary damage to the myocardium. When hearts refibrillate after defibrillation, it is unnecessary to use higher energy settings for subsequent defibrillation attempts. Instead, an antiarrhythmic drug should be administered and another shock of the same intensity that defibrillated the first time should be applied.

Degeneration of knitted Dacron grafts.

This report describes three instances of severe deterioration in tensile strength of knitted Dacron grafts (Weaveknit) supplied prior to 1969. Similar deterioration has been encountered previously by us and other surgeons. All patients with this type of graft should be re-examined periodically and, if deterioration is detected at operation, the entire graft probably should be replaced. These experiences indicate that further investigation and, possibly, some alteration of the manufacturing process are warranted.

Duodenal ulcer: its treatment by parietal cell vagotomy at the time of cardiovascular operation.

The existence of duodenal ulcer disease constitutes a potential threat during the recovery that follows any major operative procedure. At the time of cardiovascular operations, it would be desirable to treat the coexisting duodenal ulcer disease with a definitive ulcer operation if it could be done without entering the gastrointestinal (GI) tract, thereby eliminating the risk of graft contamination. Parietal cell vagotomy with pyloroplasty meets these conditions. During an 18-month period, 309 patients underwent cardiovascular procedures; ten underwent parietal cell vagotomy at the same time for treatment of duodenal ulcer. None of the patients experienced GI complications or the development of any other operative complications referable to the gastric procedure. Parietal cell vagotomy for active duodenal ulcer disease seems to be eminently suited as a companion for cardiovascular procedures that must be expedited.

A new coronary perfusion cannula.

A flexible but rigid-walled nontraumatic cannula has been developed for perfusion of the coronary arteries or visceral branches of the aorta.

Clamp for wire closure of sternum.

A modification of the Kocher clamp used for wire closure of the sternum is described. With the clamp applied securely to the individual strands, the wire can be readily twisted; the shorter length of the clamp allows the surgeon a much firmer grip on the wire and saves considerable time during closure.

Long-term follow-up of the Vineberg internal mammary artery implant procedure.

This report describes the 20-year follow-up of a patient who had undergone a double internal mammary implantation for coronary occlusive disease. A lack of similar reports in the literature suggests that such survival is rare, but this case indeed documents the fact that the internal mammary arteries can revascularize the myocardium, and this patient's continued survival appears to depend entirely on this collateral blood flow.

Successful treatment of transection of aortic arch and innominate artery.

A patient was seen with a widened mediastinum following rapid deceleration injury. A retograde angiogram showed rupture of the transverse aortic arch and occlusion of the origin of the innominate artery. At operation cardiopulmonary bypass with systemic, cerebral, and myocardial preservation were used to provide a safe approach for inserting a graft to successfully restore normal circulation.

Access to the thorax by incision.

BACKGROUND: For years the standard access to the thorax has been by posterolateral or other muscle cutting thoracotomy incisions. These are accompanied by significant discomfort and often limitation of shoulder girdle movement. To obviate these distressing features, the less traumatic median sternotomy was recommended. In the last ten years, several types of mini or axillary thoracotomies have been described. We believe that the vertical axillary thoracotomy is the best of these incisions as no major muscles are divided, it can be created rapidly, and exposure is excellent. STUDY DESIGN: We compared the operative approaches from the point of view of the duration of postoperative hospitalization, the length of the operating time, the incidence of postoperative atelectasis, and persistence of incisional pain. RESULTS: The vertical axillary thoracotomy showed a definite advantage in all these categories. CONCLUSIONS: These findings suggest that the vertical axillary thoracotomy is the incision of choice for most thoracic procedures as the incision is small and quickly made. Because there is limited division of muscles, the convalescence is smooth and uncomplicated.

Vagotomy of the fundic gland area of the stomach without drainage. A definitive treatment for perforated duodenal ulcer.

Twelve patients in Sweden and thirteen patients in Houston underwent selective proximal vagotomy or parietal cell vagotomy, respectively, for the treatment of perforated duodenal ulcer. A drainage procedure was performed in four of the former and in none of the latter group of patients. There were no operative complications and no operative deaths. Twenty-two of the patients were followed from six months to four years. No patient has recurrent ulcer, dumping, diarrhea, or other significant gastric symptoms during the follow-up period. At the time of their last follow-up, the results were considered excellent or good in all twenty-two patients. The results of this study suggest that SPV or PCV without drainage may be the method of choice for the definitive treatment of all patients with perforated duodenal ulcer who have no obstruction and no contraindications to an operative procedure of greater magnitude than simple closure.

Carcinoma of the esophagus.

Carcinoma of the esophagus remains difficult to detect while it is localized to the mucosa. The ideal treatment is removal of all tissue that contains tumor. Usually reconstruction using the stomach is preferred over the use of gastric tubes, colon, and jejunum, although these will serve satisfactorily. Maximal palliation with relief of dysphagia is best achieved by removal of the obstructing lesion when possible, even if some tumor remains. When resection is not practical, bypass anastomoses proximal to the tumor occasionally may be used to relieve the obstruction and the associated dysphagia. Irradiation and chemotherapy may improve the results of therapy. To permit earlier detection, better screening tests are needed.

Coronary artery bypass surgery in elderly patients.

Seventy-five patients 65 years of age and older had coronary artery bypass surgery during 2 years at Scott and White Memorial Hospital with a 4 per cent mortality rate. An average of 3.1 grafts were placed and 5.1 units of blood were used during 13 days of postoperative hospitalization. Sixty-one patients were in New York Heart Association Class IV, 12 were in Class III, and 2 had other indications for coronary artery bypass. One year following surgery there were 60 patients in Class I, 6 in Class II, 3 in Class III, and 1 in Class IV; 1 patient was dead, and 4 were lost to follow-up. Our conclusion is that coronary artery bypass grafting can be performed with an acceptable mortality rate in the elderly and that age alone should not be considered a contraindication to the operation.

Ventral burn in rats: an experimental model for intravital microscopic study of microcirculation.

A novel technique of application of controlled ventral scald burn to rodent, whose back is inaccessible because of preburn preparation, is described. Boiling water is applied across a polyethylene membrane that partially envelops the subject. The technique is simple, economical, reproducible and allows intravital microscopic study of microcirculation in a remote muscular bed before and after burn injury.

Rational use of operation in pericardial constriction.

The most appropriate operation for constricting pericardial disease must be selected to provide optimum chance for permanent recovery of myocardial function with minimal morbidity. Our 18 patients demonstrate the changing cause of pericardial constrictive disease and the application of newer surgical treatments. Good results were obtained in 16 patients.