The Miami Vices in the CCU. Part I. Cardiac manifestations of cocaine use.

There is a widespread misconception that the social use of cocaine is not associated with serious medical complications. It is therefore necessary to reemphasize that cocaine use can precipitate life-threatening cardiac events even in the absence of underlying heart disease.

Wide complex tachycardia: diagnosis and treatment.

A wide QRS complex tachycardia that cannot be immediately identified, and which on clinical grounds requires prompt treatment, should be converted electrically. Drug management can be time consuming, and agents that block AV transmission, that is, verapamil and propranolol, may be life-threatening.

Platelet aggregation and atherosclerosis.

The relationship of platelet aggregation to coronary and cerebral ischemic attacks has been well established. A number of clinical trials have shown that the daily use of aspirin 160 to 325 mg daily, dipyridamole 300 to 400 mg daily, or both are effective in preventing platelet aggregation, and results in a statistically significantly reduction in the incidence of coronary events and transient ischemic cerebral attacks.

Catecholamines, potassium, and beta-blockade.

Stress-induced hypokalemia represents a transient risk factor for malignant arrhythmias in patients with coronary artery disease. The adrenergic nervous system serves as a major control system for the transport of potassium across the cell membrane. Nonselective beta-blockade presents epinephrine-mediated hypokalemia. This helps explain a possible mechanism for the significant improvement in morbidity and mortality rates of patients taking long-term propranolol therapy in the Beta Blocker Heart Attack Trial report.

A new device for the prevention of sudden death.

The clinical implications and use of an AICD are presented. This device is still under investigation, but has proved to be highly successful in trials to date.

Ventricular arrhythmias: a perspective on management.

Antiarrhythmic drugs are associated with a significant incidence of arrhythmogenic effects, as well as other cardiac and extracardiac side effects. Thus, it is important that the decision to treat ventricular arrhythmias be made on the bases of the frequency of the arrhythmia, its qualitative features, and the presence or absence of underlying heart disease. These features influence the risks of sudden arrhythmogenic death.

Percutaneous transluminal coronary angioplasty: an update.

Rapid and progressive improvement in techniques and decreased morbidity and mortality rates have taken place since the introduction in 1977 of PTCA for the treatment of coronary artery disease. PTCA is now performed worldwide. Originally used for proximal single-vessel disease, which is still the ideal lesion, criteria for PTCA have expanded to include multiple stenotic lesions in one or more vessels, distally located obstructive lesions, patients with prior coronary artery bypass surgery, and patients with acute myocardial infarction where PTCA is performed in combination with streptokinase lysis of an obstructive thrombus.

Cardiac catheterization after an acute myocardial infarction.

An important question facing the profession each and every day is whether to recommend cardiac catheterization to a patient who has just had an acute myocardial infarction. Criteria have been proposed and ongoing studies are helping to establish guidelines to determine which survivors of an uncomplicated myocardial infarction can benefit from a knowledge of the coronary anatomy and ventricular function. In the case presented in this vignette the problem is related to angina recurring during the early stages of an acute myocardial infarction. Postinfarction angina often reflects subtotal obstruction of a major coronary artery that supplies either a portion of the myocardium that had infarcted or myocardium distant from the zone of the infarction. This is a high-risk group. Here the criteria are firmly established. Coronary angiography should be performed promptly to help determine whether coronary artery bypass surgery or balloon angioplasty is indicated.

Severe coronary artery disease in the asymptomatic patient.

Asymptomatic patients more than 40 years of age who have major risk factors for coronary atherosclerosis (i.e., strong familial history for coronary atherosclerosis, hypertension, hypercholesterolemia, or diabetes mellitus or history of heavy cigarette use) should be given an exercise tolerance test. Establishing the presence or absence of coronary artery disease will help in management whether this be medical, surgical, or preventative.

Amiodarone--an investigative drug in the coronary care unit.

Amiodarone is an investigative antiarrhythmic drug in the United States. However, it has been used successfully in European countries for the past 14 years. Amiodarone is effective in the long-term management of resistant supraventricular and ventricular arrhythmias. Although a very useful addition to the antiarrhythmic drugs currently in use, it has potential side effects that have delayed its acceptance by the Food and Drug Administration. The consensus of opinion among the clinical investigators of amiodarone is that it will be released for limited clinical use in the near future. Cardiovascular nurses involved in the design, coordination, and conduction of clinical investigations need to be vigilant in objectively monitoring and documenting both the potential efficacy and possible adverse effects of all interventions in research subjects.

Use of the "diving reflex" in paroxysmal atrial tachycardia.

Immersing the patient's face in cold water to induce the "diving reflex" is a quick and simple method of treating paroxysmal supraventricular tachycardia. Patients can be trained to perform the "diving reflex" at home. There are many advantages to this method of treatment when compared to many of the other therapies. Polyuria up to 3 L is often noted during the first 90 minutes of a paroxysmal tachycardia. The diuresis is thought to be due to atrial distention with resultant inhibition of antidiuretic hormone secretion.

Intravenous nitroglycerin in acute infarction. Part II.

Intravenous nitroglycerin is helpful as an adjunct to the judicious use of diuretics in the management of CHF complicating an acute MI. The clinical end point when using intravenous nitroglycerin is a reduced LVEDP, 16 mm Hg, measured either by PA diastolic pressure or PCWP, provided peripheral perfusion is not compromised, i.e., as blood pressure adequate for peripheral needs (absence of signs of hypovolemic shock). The reduction in cardiac work plus the improvement in coronary flow to the ischemic area can help reduce infarct size, especially if intravenous nitroglycerin is started within the first 6 hours of the onset of an acute MI.