False-Positive Thromboscintigram Resulting From Lymphedema��A Roentgen Pathological Model

Abnormal thromboscintigrams were observed in patients with lymphatic obstruction. This syndrome was reproduced by surgically ligating the lymphatic drainage of the lower extremity of a dog prior to thromboscintigraphy.     

Histamine attenuates the arrhythmogenic effects of norepinephrine in hearts of spontaneously hypertensive rats

A potential physiological role for cardiac histamine and its interaction with norepinephrine were investigated in isolated left ventricles from spontaneously hypertensive rats (SHR). Prior to drug administration, left ventricle-to-body weight ratios and spontaneous firing rates (beats per min) were significantly increased in SHR ventricles vs. age- and sex-matched controls (WKY). Also, action potential duration was significantly prolonged in SHR at all levels of repolarization. In all hearts, norepinephrine (10(-7)-10(-4) M) increased spontaneous rate and the percent incidence of arrhythmias. The H2-receptor antagonist cimetidine (10(-5) M) potentiated the rate and arrhythmogenic effects of norepinephrine in SHR and, to a lesser extent, in WKY preparations; propranolol (10(-6) M) reduced them. Histamine (10(-7) M) also inhibited the norepinephrine-induced increase in arrhythmias in SHR, but not in WKY. The attenuation of adrenergically induced rhythm disturbances by histamine and their potentiation by cimetidine in hypertensive hearts support the hypothesis that histamine plays a role as a postjunctional modulator of adrenoceptor function in a setting of hypertension and myocardial hypertrophy.     

Dihydropyridine sites separate from junctional sacroplasmic reticulum in hypertension

Distribution patterns on linear sucrose gradients for dihydropyridine (DHP) binding sites and Mr 300K polypeptides marker for junctional sarcoplasmic reticulum were determined in left ventricular microsomes of control and chronically pressure-overloaded cat hearts. Major peak of DHP sites corresponded in position and shape to distribution of Mr 300K polypeptide in controls but appeared at a lighter buoyant density in hypertrophy, similar to junctional plasma membrane (T-tubules) isolated from normal microsomes by French press treatment of dyad fraction.     

Complications of coronary artery surgery in diabetic patients

Postoperative mortality and morbidity of diabetic versus nondiabetic patients undergoing primary coronary artery bypass grafting (CABG) were analyzed. In 1988, 711 patients had CABG procedures, of which 565 were nondiabetic and 146 diabetic. The two groups of patients were statistically similar in regard to age, weight, tobacco and ethanol use, and preoperative levels of cholesterol, triglycerides, blood urea nitrogen (BUN), and creatinine. Preoperative serum glucose levels were significantly elevated in diabetic patients (182 vs. 106, P less than .001). Cardiac output, ejection fraction, and bypass, crossclamp time, and total operating room times were not different for the two groups. Emergent and urgent procedures had a significantly higher mortality rate than elective cases (11.3% and 6.6% vs. 1.7%, respectively; P less than 0.05), but this was independent of the patient's diabetic status. Women had a higher mortality rate than men (6.5% vs. 2.9%; P = 0.05) although within each gender group, there were no differences between diabetics and nondiabetics. There were 27 patients with complications in the diabetic group (18.5%) and 47 in the nondiabetic group (8.3%; P less than .001). The types of complications within the two groups differed in that wound infections (7.5%), postoperative arrhythmias (4.8%), respiratory failure (4.1%), and intra-aortic balloon pump use (4.1%) were significantly greater (P less than .05) in the diabetic patients compared to the nondiabetic (0.9%, 1.8%, 0.4%, and 1.4%, respectively). Occurrences of postoperative pneumothorax, reoperation, myocardial infarction, stroke, urinary tract infection, and pneumonia were similar in both groups.(ABSTRACT TRUNCATED AT 250 WORDS)     

Screening mammography: referral practices of Los Angeles physicians

The American Cancer Society (ACS) recommends annual screening mammography for asymptomatic women over 50 years old. In a survey of attitudes and referral practices toward screening mammography, one-fifth (886) of the 4200 physicians queried returned a postage-paid questionnaire. Only 11% of respondents followed the ACS guidelines. Physicians under 40 years old, in group practice, or in surgical specialties were more apt to refer their patients for screening. The major deterrent to referral was the perceived high cost and low yield of screening. However, 80% of the physicians indicated they would refer patients over 50 who requested annual screening. Annual mammography screening is underused; greater efforts must be directed toward educating physicians and patients regarding its value and toward lowering its cost.