Unstable angina. Rational approach to management.

Unstable angina can be defined by the development of chest pain at rest, usually with reversible S-T segment changes. It has been found in patients in whom angina developed at rest in the cardiac catheterization laboratory that a decrease in coronary sinus oxygen saturation preceded changes in left ventricular relaxation and contractility that preceded the development of chest pain and/or electrocardiographic changes. Increases in heart rate and/or blood pressure followed, rather than preceded, these ischemic episodes.

ECT, emergent dyskinesia, and depression.

Three depressed patients developed a dyskinesia directly following ECT. In each case the dyskinesia improved some time after cessation of ECT. All patients had prior treatment with an antipsychotic drug and previous diagnoses of schizophrenia or schizoaffective disorder.

Localization of regional myocardial ischemia by recording of monophasic action potentials.

Identification of regional myocardial ischemia by TQ-ST segment mapping, while commonly used, is relatively imprecise and nonspecific. In 41 open-chest dogs we examined whether monophasic action potentials (MAPs) recorded from the myocardial surface by means of a new contact-electrode technique could be used to more precisely and specifically index regional myocardial ischemia. After ligation of the left anterior descending coronary artery (LAD), epicardial and endocardial MAPs from the ischemic region demonstrated shortening of plateau duration followed by a progressive loss in amplitude to 48 +/- 8% and in maximum upstroke velocity (dV/dtmax) to 9 +/- 2% of control (n = 7).

Maintenance of aerobic metabolism during global ischemia with perfluorocarbon cardioplegia improves myocardial preservation.

We used phosphorus-31 nuclear magnetic resonance to test the ability of a perfluorocarbon blood substitute that has been shown in previous studies to improve oxygen delivery to hypothermic myocardium to maintain aerobic high-energy phosphate metabolism during total global ischemia. Twenty-three isolated perfused rabbit hearts were subjected to 180 min of hypothermic (23 degrees C) global ischemia followed by 45 min of normothermic reperfusion. Hearts received multiple doses of a cardioplegic solution that contained either oxygenated perfluorocarbon (Fluosol O2), nonoxygenated perfluorocarbon (Fluosol N2), or standard crystalloid hyperkalemic cardioplegic solution (STD-KCl) at 30 min intervals.

Propranolol-induced postoperative hypertension following coronary artery bypass grafting.

Fifteen patients receiving propranolol preoperatively and undergoing coronary artery bypass grafting had serum propranolol levels determined preoperatively and at several times early postoperatively. In addition, the patients' hemodynamic parameters and postoperative sodium nitroprusside dose requirements were monitored. All patients had significant multivessel disease and normal left ventricular function.

Parenteral nitroglycerin: clinical usefulness and limitations.

It would appear that nitroglycerin, which has been the time-honored therapy for angina pectoris, has a much broader therapeutic scope. Since the Food and Drug Administration has only recently released intravenous nitroglycerin for general clinical use, other clinical applications may develop in the future. Intravenous nitroglycerin appears to provide predictable and rapid lowering of left ventricular filling pressure and mean arterial pressure in patients with ischemic heart disease.

Medical students' performance in reporting alcohol-related problems.

Medical students reviewing the hospital course of a young man with acute gastritis and alcoholism accurately reported the physical aspects of the patient's presentation and course, but paid less attention to the issue of alcoholism.

Improved myocardial preservation during global ischemia by continuous retrograde coronary sinus perfusion.

To investigate whether retrograde continuous low-pressure perfusion of the coronary sinus could deliver cardioplegic solutions with oxygen and substrate beyond stenoses and result in improved myocardial preservation, we subjected 41 canine hearts to 90 minutes of ischemia with an occlusion on the circumflex coronary artery. There were four groups: Group I, antegrade (aortic root) crystalloid cardioplegia every 30 minutes during ischemia; Group II, antegrade plus topical cooling; Group III, continuous retrograde perfusion; Group IV, same as Group III, with an oxygenated perfluorocarbon. All solutions had a PO2 of 400 to 500 mm Hg.

Enhanced myocardial protection with verapamil prior to postischemic reflow.

Reperfusion of the heart after induced myocardial ischemia may be associated with severe myocardial damage, characterized by massive calcium influx and accumulation in the heart cells. The present study was undertaken to investigate whether verapamil, a slow channel calcium blocker, administered prior to reperfusion, might reduce this reflow injury without causing depression of heart function. Thirty-two isolated, perfused rabbit hearts were subjected either to 45 minutes of normothermic or 150 minutes of hypothermic global ischemia.

Pharmacokinetics of cefoxitin in patients at term gestation: lavage versus intravenous administration.

Despite the increasing popularity of antibiotic prophylaxis to reduce febrile morbidity in patients who undergo cesarean delivery, little is known of the pharmacokinetics of antibiotics in the patient at term gestation. This study was designed to elucidate the pharmacokinetics of cefoxitin when administered intravenously or by uterine and peritoneal lavage at cesarean section. Significant differences were found in the values for total body clearance area under the serum concentration-time curve (AUC), and K21 of cefoxitin administered intravenously to pregnant patients at term gestation compared to values for these parameters observed in nonpregnant patients.

Comparison of intravenous nitroglycerin and sodium nitroprusside in acute myocardial infarction.

Initial studies from our institution demonstrated beneficial anti-ischemic effects of short-term infusion of intravenous nitroglycerin in patients with acute myocardial infarction. At lower doses, nitroglycerin was shown to be principally a venodilator; at higher doses, a mixed venous and arterial dilating effect was demonstrated. The acute hemodynamic effects of nitroglycerin varied in the presence or absence of left ventricular failure; patients with the most severe degree of left ventricular dysfunction had the most beneficial hemodynamic effect.

The role of social support in the functioning of patients with unipolar depression.

The authors studied 44 outpatients with unipolar depression to determine the association among social support systems, life events, social adjustment, and depressive symptoms. Social support had a reasonably high correlation with outcome measures. Patients with high social support had significantly better scores than those with low social support on the Hamilton Rating Scale for Depression and the Social Adjustment Rating Scale Self-Report.

The use of breast stimulation to ripen the cervix in term pregnancies.

Induction of labor is frequently a matter of medical or obstetric necessity. Patients with worsening maternal or fetal problems often have an unfavorable cervix which may preclude successful induction of labor. In a blind, randomized, controlled trial of breast stimulation to ripen the cervix at term, it was found that breast stimulation was associated with a 45% incidence of spontaneous labor.

Improved myocardial protection with perfluorocarbon cardioplegia.

An oxygenated perfluorocarbon solution containing 25 mEq/L potassium has been investigated as a potentially useful cardioplegic solution to be administered to patients undergoing prolonged induced global myocardial ischemia during open-heart surgical procedures. Experimental studies have demonstrated that, compared to simply crystalloid and cold-blood cardioplegic solutions, an oxygenated perfluorocarbon cardioplegic solution administered at low temperatures can deliver oxygen to the ischemic heart and that this available oxygen is utilized by the heart. In an experimental study in which a Fluosol-43 solution was compared to both crystalloid and oxygenated-blood cardioplegia, Fluosol-43-treated hearts demonstrated better recovery of left ventricular function following postischemic reperfusion.

A randomized clinical trial of intravenous nitroglycerin in patients with acute myocardial infarction: benefits of early treatment.

A prospective randomized clinical trial of intravenous nitroglycerin administered for 48 hours following acute infarction was undertaken to determine whether clinical improvement and/or preservation of ischemic myocardium could be demonstrated. One hundred four patients were randomized to receive either nitroglycerin or placebo infusion. Nitroglycerin infusion was titrated to lower mean arterial pressure 10% using non-invasive monitoring.

Clinical reading and writing skills of junior medical students.

A three-year study was designed to assess general reading and writing skills of 231 entering medical students and to compare these scores with those of clinically oriented reading and writing skills in the same cohort of students three years later. Standardized reading and writing tests were administered to all entering freshmen in the class of 1982. Clinical reading and writing examinations were developed by the authors and members of the faculty.

Optimal myocardial protection with fluosol cardioplegia.

An oxygenated perfluorocarbon cardioplegic solution was examined, utilizing a blood-perfused canine model. Twenty-one animals were divided into three equal groups, and each animal received Fluosol cardioplegia at one of three infusion temperatures: 20 degrees C, or 4 degrees C. All hearts underwent 90 minutes of ischemia, during which time 150 ml of the cardioplegic solution was infused every 30 minutes.