Involvement of an enchondroma in relapsing polychondritis.

We describe a 49-year-old Caucasian woman with relapsing polychondritis involving ears, eyes, nose, and airways. An enchondroma in the left humerus was also involved. This unusual manifestation of the disease has not been previously reported.

Serum myoglobin, creatine kinase and creatine kinase-MB as mutually supportive indices of myocardial infarction and infarct size.

A comparison was made between the appearance of serum myoglobin and creatine kinase in 22 patients with acute myocardial infarction who were admitted to a coronary-care unit within four hours of onset of chest pain. The MB isoenzyme of creatine kinase was measured in 12 patients. The more rapid appearance and disappearance of myoglobin relative to creatine kinase and creatine kinase-MB was confirmed, as was the correspondence between their respective peak values. A significant correlation was also obtained between the area under the myoglobin time-course and the respective peak levels. Whereas creatine kinase activity declined exponentially from a single peak, myoglobin appeared in multiple episodes inadequately represented by a single peak value and having no clear clinical correlation. The role of myoglobin as a diagnostic aid in myocardial infarction is probably limited to its ability to support creatine kinase and creatine kinase-MB as indices of infarct size.

Amiodarone in long term management of refractory cardiac tachyarrhythmias.

Amiodarone was used in 30 patients with tachyarrhythmias refractory to treatment with several antiarrhythmic agents. In 18 patients with supraventricular arrhythmias (recurrent atrial tachycardia in seven; atrial fibrillation, recurrent in four and persistent in five; Wolff-Parkinson-White syndrome in two), complete control was obtained in eight and marked improvement in eight patients. Conversion of persistent atrial fibrillation to sinus rhythm was documented in three patients. Congestive heart failure improved markedly in three patients who had persistent atrial fibrillation during amiodarone therapy. In 12 patients with tachycardia of ventricular origin effective control was obtained in nine. The incidence of side effects was low. Amiodarone is effective in maintaining sinus rhythm in many patients with both supraventricular and ventricular tachyarrhythmias when standard antiarrhythmic agents have failed.

Psittacosis: a clinical spectrum in New Zealand.

Two patients suffering from psittacosis, of whom one had renal impairment, are described. Both recovered after treatment including the antibiotics, ampicillin and doxycycline. Chlamydia psittacae is endemic among New Zealand birds. The difficulties of diagnosis are discussed.

Effects of intravenous verapamil on cardiac arrhythmias and on the electrocardiogram.

The effects of intravenous verapamil on the electrocardiogram in 15 patients with heart disease in sinus rhythm and in 44 patients with supraventricular and ventricular tachyarrhythmias were evaluated. Verapamil prolonged the P-R interval without effect on the QRS duration or the Q-Tc interval. In patients with atrial flutter and fibrillation, A-V block was increased, with slowing of the ventricular rate, in almost all cases but sinus rhythm was restored in only 1 of 12 patients in atrial fibrillation and in 2 of the 11 patients with flutter. Verapamil had no effect in 3 patients with atrial fibrillation complicating WPW syndrome; in 1 of 5 patients with ventricular tachycardia it caused reversion to sinus rhythm. Sinus rhythm was restored promptly by verapamil in 13 of 17 patients with paroxysmal supraventricular tachycardias; in 2 others, sinus rhythm became established 1 to 2 hours after administration of the drug. Transient hypotension, not requiring treatment, was the only side effect noted but not in the patients with supraventricular tachycardias, in whom blood pressure generally increased after reversion to sinus rhythm by verapamil.

Idioventricular rhythm complicating acute myocardial infarction.

The incidence, natural history, prognosis, and electrocardiographic characteristics of idioventricular rhythm complicating acute myocardial infarction are described. It occurred as a transient arrhythmia nearly always within 24 hours of infarction in 61 (8%) of 737 patients, and was characterized by paroxysms of between 6 and 20 beats with widened bizarre QRS complexes at a rate of between 60 and 90 a minute. Most cases showed fusion beats and P waves dissociated from the QRS complexes, and in many cases idioventricular rhythm started during the slow phase of sinus arrhythmia. Though it usually occurred in patients with moderately severe transmural infarcts, the incidence of ventricular fibrillation and subsequent mortality was no greater than in patients with infarcts of equivalent severity who did not have idioventricular rhythm. It is concluded that this rhythm is a common and relatively benign arrhythmia complicating myocardial infarction, and that it should be distinguished from ventricular tachycardia.