Absence of facilitated glucose disposal (Staub-Traugott effect) in subjects with hypopituitarism.

Improved glucose tolerance follows glucose challenges given in rapid succession, the Staub-Traugott effect. The cause for this facilitated glucose disposal is not clear. Augmented insulin release, prior "insulinization" of cells, and suppression of a pituitary factor or free fatty acids (FFA) are previously suggested mechanisms. For information bearing on the role of the pituitary in this phenomenon, study of the Staub effect was undertaken in hypopituitary patients receiving replacement thyroid, cortisone, and sex-steroid therapy and in normal untreated controls. All subjects received three intravenous injections of glucose (0.5 g/kg) at hourly intervals. Plasma glucose, FFA, and insulin were measured. Whereas a definite Staub effect was seen in each control subject, this phenomenon was conspicuously absent in seven hypopituitary patients similarly studied. Patterns of peripheral insulin response were similar for both groups: FFA levels fell more slowly in the hypopituitary subjects. Normal pituitary function appears to be required for the Staub effect. Incremental peripheral insulin levels do not explain the effect. Subnormal suppression of free fatty acids and impaired induction of key glycolytic and glycogenic enzymes are alternative explantations for the absence of the Staub effect in hypopituitary subjects.     

Effect of the renin-angiotensin system on limb circulation and metabolism during exercise in patients with heart failure

The maximal aerobic exercise capacity of patients with chronic heart failure is frequently decreased because of inadequate blood flow to working skeletal muscle. To investigate whether this reduced flow is in part due to interference by angiotensin II with arteriolar dilation in working muscle, the effect of the angiotensin-converting enzyme inhibitor captopril on leg blood flow, leg vascular resistance, leg oxygen consumption (VO2) and leg lactate release during maximal upright bicycle exercise was examined in 12 patients with heart failure (maximal VO2 10.7 +/- 3.1 ml/min per kg). Captopril decreased leg resistance at rest (258 +/- 115 to 173 +/- 67 U, p less than 0.01) and maximal exercise (68 +/- 69 to 45 +/- 29 U, p less than 0.01) associated with proportionately similar decreases in systemic vascular resistance. However, maximal exercise duration and maximal VO2 were unchanged and, at identical peak exercise work times, there was no improvement in leg blood flow (2.0 +/- 0.9 to 2.0 +/- 1.1 liters/min, p = NS), leg VO2 (261 +/- 104 to 281 +/- 157 ml/min, p = NS) or leg lactate release (269 +/- 149 to 227 +/- 151 mg/min, p = NS). These data suggest that, during exercise in patients with heart failure, angiotensin II does not interfere with blood flow to working skeletal muscle.     

Serum high density lipoprotein cholesterol correlates with presence but not severity of coronary artery disease

An elevated serum level of low density lipoprotein (LDL) is a risk factor for the development of coronary artery disease, whereas elevated levels of high density lipoprotein (HDL) appear to have a protective effect, and the total cholesterol to HDL ratio has been suggested as an improved method for assessing risk. We determined cholesterol, HDL and triglycerides in 189 patients undergoing diagnostic cardiac catheterization to determine if these variables correlate with the severity of coronary artery disease assessed as the number of major coronary vessels having ≥ 70 percent stenosis. HDL was higher in the group with zero vessel disease (54 ± 2.3 mg/dl ± SEM) than in those with one, two or three vessel disease (43 ± 1.8, 45 ± 1.8 and 51 ± 1.2, respectively), and the cholesterol to HDL ratio was lower in the group with zero vessel disease (4.1 ± 0.2 compared to 6.1 ± 0.3, 5.7 ± 0.2 and 6.4 ± 0.3 in the groups with 1, 2 and 3 vessel disease).Using analysis of variance, patients with no coronary artery disease (zero vessel disease) differed from those with coronary artery disease in HDL (p < 0.005), triglycerides (p > 0.01), cholesterol (p < 0.005) and cholesterol to HDL (p > 0.005), but no significant differences were found between patients with coronary artery disease and a different number of vessels involved. There were no significant differences between the groups in age, and although the group with zero vessel disease had more females than the others, there were no differences in cholesterol, HDL, cholesterol to HDL ratio, or triglycerides between male and female patients with no coronary artery disease. We conclude that the cholesterol to HDL ratio correlates with the presence but not severity of coronary artery disease.     

Innominate artery aneurysm with thrombus: detection by two-dimensional echocardiography

A 51 year old man with an innominate artery aneurysm presented with claudication and ischemia of the right forearm and hand. Two-dimensional echocardiography visualized the saccular aneurysm and a pedunculated mobile thrombus within it that were not seen during aortic arch angiography. Two-dimensional echocardiography, shown to be useful in identifying intracardiac masses and aortic aneurysms, may be important in selecting patients with increased risk of embolization.     

Electrocardiographic criteria for differentiating aberrancy and ventricular extrasystole in chronic atrial fibrillation: validation by intracardiac recordings

Many electrocardiographic criteria have been proposed for the differentiation of ventricular extrasystole and supraventricular conduction with aberrancy in atrial fibrillation but the validity of these have not been confirmed by intracardiac studies. We recorded His bundle electrograms in nineteen patients (eleven men, eight women) referred for diagnosis of abnormal QRS complexes in the context of chronic atrial fibrillation. Of 1,068 wide QRS complexes analyzed, 91% proved to be of ventricular origin. Electrocardiographic criteria which were specific for ventricular extrasystole included: left bundle branch block morphology, right bundle branch block morphology with a monophasic R in lead V1 or an RS or QS pattern in lead V6, presence of a "compensatory pause", i.e., compensatory cycle (V2-V3) longer than the average cycle length of ten normally conducted beats preceding the abnormal complex (927 +/- 317 vs 780 +/- 199, mean +/- SD in msec. p less than 0.005), frontal QRS axis of the abnormal complex directed superiorly or to the right and the presence of a "short-long" cycle sequence. Right bundle branch morphology with a triphasic R in lead V1 or QRS pattern in V6 and concordant initial vector in lead V1 or in more than one ECG leads were very specific for supraventricular conduction with aberrancy. Analysis of coupling interval and Ashman's phenomenon, i.e., the long-short cycle sequence, were not specific for supraventricular conduction with aberrancy. We conclude that in digitalis-treated patients with chronic atrial fibrillation the majority of abnormal QRS complexes are of ventricular origin. The diagnosis of ventricular extrasystole or aberrancy can be made using a single ECG lead (V1) and applying a combination of easily applied criteria.     

Portal and peripheral vein concentrations of insulin and glucagon after arginine infusion in morbidly obese subjects

Five morbidly obese subjects with fasting normoglycemia underwent catheterization of portal and peripheral veins immediately prior to jejunoileal bypass surgery. Levels of immunoreactive insulin (IRI), immunoreactive glucagon (IRG), and glucose were determined in simultaneously obtained serum samples before and after infusion of arginine. Portal levels exceeded peripheral levels by at least 50% with IRI and by 30%–40% with IRG. These results were similar to those reported in nonobese subjects and show that in morbid obesity as well as in nonobese states, peripheral insulin to glucagon molar ratios ($\text{I}\text{G}$) underestimate portal $\text{I}\text{G}$. Although hepatic extraction was not specifically measured, the data suggest that the peripheral levels of insulin and glucagon reported in morbid obesity result from alterations in secretion and not altered extraction.     

Procainamide-induced lupus erythematosus pericarditis encountered during coronary bypass sugery

Procainamide is probably the most common offending drug responsible for the drug-induced lupus erythematosus syndrome today. Pericarditis has been reported to occur in from 14 to 18 per cent of the cases of procainamide-induced lupus erythematosus, and occasional reports of massive pericardial effusion, pericardial tamponade and constrictive pericarditis have appeared in the literature. We describe a patient who presented with features of procainamide-induced lupus erythematosus without any clinical evidence of pericarditis. He underwent coronary bypass surgery 12 days after administration of the drug was stopped and was found to have a significant pericardial effusion at the time of surgery; histologic examination of pericardial tissue and pericardial fluid confirmed that the pericardial effusion was related to the procainamide-induced lupus syndrome. The incidence of pericarditis in procainamide-induced lupus erythematosus may be higher than presently accepted figures would indicate. Symptoms and signs related to procainamide-induced lupus pericarditis may cause diagnostic confusion with common postoperative bypass complications; the full implications of this disease entity to the patient undergoing coronary bypass are unknown.