Synthesis of disaturated phosphatidylcholine by cholinephosphotransferase in rat lung microsomes.

1. Incubation of rat lung microsomes with cytidine diphospho[methyl-14C]choline resulted in synthesis of radioactively labeled phosphatidylcholine. 2. 10-15% of this phosphatidylcholine appeared to be disaturated species. In similar experiments with rat liver microsomes only 2-3% of the radioactivity was present in the disaturated species. 3. When de novo synthesis was blocked after 5 min by addition of Ca2+ no increase in the proportion of disaturated phosphatidylcholine was observed upon further incubation of lung microsomes. Under these conditions the enzymes involved in a remodeling mechanism, i.e. phospholipase A and acyl-CoA: lysophosphatidyl-choline acyltransferase, remain fully active. 4. Addition of diacylglycerols from egg phosphatidylcholine containing trace amounts of di[1-14C]palmitoyl glycerol resulted in direct incorporation of 14C label into phosphatidylcholine. The rate of phosphatidylcholine synthesis measured from incorporation of di[1-14C]palmitoyl glycerol equalled that observed with labeled CDP choline. 5. These results support the conclusion that disaturated phosphatidylcholine in lung can be formed by direct utilization of disaturated diacylglycerol and is not produced exclusively via remodelling of de novo synthesized unsaturated species.

The importance of two-dimensional echocardiography in the location of a bullet embolus to the right ventricle.

Bullets which enter a sufficiently large vein may embolize to the right ventricle. This finding is usually determined after the bullet has been removed from the heart. A chest x-ray study cannot, however, differentiate with certainty between localization in the right ventricular cavity, the right ventricular wall, or the pericardium. We recommend echocardiography to document bullet localization in the right ventricular cavity prior to surgical removal.

Perioperative intra-aortic balloon counterpulsation in cardiosurgery: a retrospective study.

From January 1986 to March 1988 50 of 1366 patients (3.7%) undergoing cardiac surgery were treated with IABP support. The 50 patients ranged in age from 43 to 79 years (mean: 63.3 years). 88% of them underwent coronary artery bypass grafting, 6% of them mitral valve replacement and the other 6% a combined procedure. IABP was inserted preoperatively in 4 patients (8%) because of cardiogenic shock, and in 18 patients because of unstable angina (36%); intraoperatively as a help during weaning from cardiopulmonary bypass in 8 patients (16%); postoperatively because of hemodynamic deterioration in 20 patients (40%). The IABP was placed by femoral puncture in 39 patients (78%), by femoral cutdown in 6 patients (12%) and by transthoracic aortotomy in 5 patients (10%). All patients received daily infusions of heparin and broad spectrum antibiotics. The overall incidence of complications was 22%. There was no mortality due to IABP-related complications.

[Coronary bypass surgery using the internal mammary artery: results and 2-year clinical follow-up in Belgian patients]. / Coronaire bypass ingreep met gebruik van de arteria mammaria interna: resultaten en klinische follow-up bij Belgische patiënten na 2 jaar.

During the years 1984-1985, 867 coronary bypass operations were performed. The internal mammary artery was used in 471 patients (54.3%). Hospital mortality was 1.3%. Complications were mainly cardiac and respiratory. In the 160 Belgian patients a clinical follow-up study was performed. Mean follow-up was 28.9 +/- 7.3 months; 80% of patients had no symptoms; 6 patients (4%) underwent recatheterization because of new symptoms. In only one patient was the mammary graft occluded. During the follow-up period 5 patients died; this represents a late mortality of 3.4%. The advantages and disadvantages of venous grafts versus bypasses using the left internal mammary artery are discussed. In coronary artery bypass grafting the internal mammary artery should be used preferentially because of its resistance to atherosclerosis and excellent long-term patency.

Subocclusion of the left anterior descending artery following blunt chest trauma.

A 54-year-old man complained of severe angina shortly after a blunt chest trauma and coronary angiography showed an isolated subtotal occlusion of the mid-left anterior descending artery. Bypass grafting was uneventful. Posttraumatic angina or supposed myocardial contusion may be due to coronary injury for which a specific treatment can be given to limit the extent of myocardial necrosis.