Effect of nicotine on prostacyclin formation in human endocardium in vitro.

The effect of nicotine on the formation of prostacyclin by human endocardium was studied in vitro. Slices of cardiac valve cusps were incubated in a saline medium and the prostacyclin-like activity generated spontaneously by the tissue specimens was assessed in terms of its capacity to inhibit ex vivo platelet aggregation. In separate experiments supernatants of valvular tissue homogenates were incubated with [14C]arachidonate. This resulted in the appearance of labelled 6-keto-prostaglandin F1 alpha in the radiochromatograms, indicating the formation of prostacyclin in the homogenates. Nicotine inhibited dose-dependently the spontaneous generation of prostacyclin-like activity (I50 approximately equal to 2 X 10(-4) M), as well as the formation of 6-keto-prostaglandin F1 alpha (I50 approximately equal to 2 X 10(-5) M), indicating an inhibitory effect of the drug on endocardial prostacyclin production.

Delayed left ventricular free wall rupture complicating coronary artery bypass surgery. A case report.

Rupture of the left ventricular free wall is a not uncommon life-threatening complication of acute myocardial infarction and after prosthetic mitral valve replacement. To our knowledge, no case of left ventricular rupture after coronary artery bypass surgery has been reported. A case is now described in which coronary artery bypass grafting was complicated by delayed rupture, which was successfully repaired. Different etiologic factors are discussed, but the cause considered most likely was trauma from elevation of and traction on the heart in exposure of its posterior aspect.

Hydroxyethylrutosides during extracorporeal circulation: effect on erythrocyte deformability.

The effect of hydroxyethylrutosides (HR) on erythrocyte deformability was studied in 13 adult patients subjected to extracorporeal circulation, in seven cases for single valve replacement and in six for coronary bypass operations. A single dose of 1.5 g HR was given by slow intravenous injection immediately before the cardiopulmonary bypass. The controls were 13 patients undergoing the same operations but without HR. In the HR-medicated valve group there was only 3% decrease in erythrocyte deformability following extracorporeal circulation, in contrast to a 41% (p less than 0.01) decrease in the control valve group. Among the coronary patients there was no such difference between the HR and the control groups, with deformability decreasing by 21 and 26%, respectively (both significant, p less than 0.05). HR administered before extracorporeal circulation thus had significant prophylactic effect on red cell deformability in patients undergoing valve replacement. Such beneficial action may improve nutritional blood flow, thereby reducing the number of postoperative complications in various organs. With higher doses and/or longer periods of administration, a favorable effect of HR might be possible also in patients subjected to coronary surgery.

Repair of ventricular septal defect in the first year of life.

In the 7-year period 1976 through 1982, 48 infants underwent repair of ventricular septal defect (VSD). Their mean age was 5.3 (range 1-11) months and mean body weight 5.4 (range 3.1-9.6) kg. "Uncomplicated" VSD, located in the membranous septum, was present in 33 cases. "Complicated" VSD in terms of muscular/multiple (n = 6), subaortic type of double-outlet right ventricle (n = 5), AV-canal type (n = 2) and straddling chordae (n = 2) was present in 15 cases. The indication of surgery was progressive left ventricular dysfunction due to pulmonary hyperperfusion and pulmonary hypertension. Right trans-atrial exposure permitted repair, patch or tunnel in 43 of the 48 infants (90%), although temporary detachment of the septal tricuspid leaflet was required on six occasions. Co-existing patent ductus arteriosus (n = 6) and atrial septal defect (n = 22) were simultaneously closed. There were three postoperative deaths (6%). One infant required a second-stage repair for incomplete VSD closure and one sustained a permanent AV-block II. Repair via right atrial exposure was associated with few complications and only one death (2%).

Aortoventriculoplasty ad modum Konno. Experience with five cases.

We have performed Konno's aortoventriculoplasty in 5 children with congenital valvular aortic stenosis and extreme annular narrowing. There was one hospital death, unrelated to the surgical procedure per se. Bleeding from the stitch holes along the patches immediately after bypass was the sole problem associated with the Konno operation in our 4 surviving patients. Preclotting of the dacron patch or use of calf pericardium did not significantly influence this type of bleeding complication. Konno's aortoventriculoplasty permitted considerable enlargement of the original annular circumference and insertion of a size of prosthesis appropriate for adult life (at least 21 mm tissue diameter) in the 4 survivors. The results were still good 1 to 5 (mean 3) years after surgery. The Konno operation is a safe procedure, which widens the hypoplastic aortic annulus to a possible maximum, relieves most forms of ventricular outflow tract obstruction and maintains the prosthetic valve in anatomic sub-coronary position, so that a left ventricular apical-aortic conduit is not required.

The effect of pentoxifylline on impaired red cell deformability following open-heart surgery.

Red blood cell deformability is essential for a normal nutritional blood flow. The effect of pentoxifylline on impaired red cell deformability following open-heart surgery was studied in 25 patients. The controls were 25 patients with equivalent surgery but no pentoxifylline. After 3 days of preoperative peroral pentoxifylline (1 200 mg/day) there was significant (mean 14%) increase of deformability. Intraoperatively, just before extracorporeal circulation, 300 mg pentoxifylline was given intravenously. During the cardiopulmonary bypass there was nevertheless significant decrease in red cell deformability in the test group (by 29%) as well as in the controls (28%). In the first 2 postoperative days there was further decrease in both groups (31% and 26%). Thereafter, however, deformability improved in the pentoxifylline group but showed additional slight decrease in the controls. By the 6th postoperative day the increase in the test group thus was 35%, whereas the controls showed a further 4% decrease. The reduction in deformability from the preoperative to the 6-day value was significantly less in the pentoxifylline group than in the controls. The study proved that red cell deformability is greatly impaired by extracorporeal circulation. Pre-bypass pentoxifylline medication had a significant prophylactic effect by enhancing the postoperative restitution of deformability.

Decreased red cell deformability following open-heart surgery.

Red blood cell deformability is essential for a normal microcirculation. The effect of extracorporeal circulation on red cell deformability was evaluated with a filtration technique in 25 patients undergoing open-heart surgery. During extracorporeal circulation there was a significant decrease in deformability, by on average 31% (p less than 0.001). No correlation was found between decrease in deformability and duration of the extracorporeal circulation procedure. In a subgroup of patients, deformability was followed also postoperatively. During the first postoperative day there was a further decrease of 17%. By the second to third postoperative days, deformability had decreased by another 23%, so that now it was less than half of the preoperative value. On the fifth to sixth postoperative days the values remained equally low. A reduction in red blood cell damage during extracorporeal circulation may be an important factor for improving nutritional blood flow. This in turn could reduce the number of complications in various organs following open-heart surgery.