Ephraim Donoso

Value of holter monitoring in assessing cardiac arrhythmias in symptomatic patients

Holter electrocardiographic monitoring in 55 symptomatic patients with syncope, palpitations or dizziness uncovered significant arrhythmias in 30 patients (55 percent). By providing an observation period of at least 24 hours including a period of sleep, the procedure aided detection and diagnosis in both symptomatic and asymptomatic patients of transient arrhythmias or conduction abnormalities not documented by routine electrocardiograms. Bradyarrhythmias accounted for the majority of arrhythmias recorded in 21 or 30 symptomatic patients (70 percent); 15 had sinus bradycardia (35 to 55 beats/min) alone and 6 also had long episodes of sinus arrest of up to 5 seconds. Two had sinus bradycardia with periods of atrioventricular block with Wenckebach phenomenon. Five patients had a tachycardia-bradycardia syndrome; three had other episodic arrhythmias and one had pacemaker failure. In 15 (60 percent) of the 25 patients without arrhythmias, monitoring did not document the cause of symptoms. Holter monitoring is of considerable value in assessing the efficacy and adequacy of drug treatment, especially in patients with known heart disease, and in detecting pacemaker malfunction. However, very long periods of monitoring may be needed to make a diagnosis in those with only sporadic symptoms.

The effect of heroin and multiple drug abuse on the electrocardiogram

Abstract The electrocardiograms (ECG) of 75 asymptomatic individuals admitted to a methadone treatment program were analyzed to determine the effect of street heroin and other drugs of abuse. All patients were free of cardiac, renal, or pulmonary disease and had no laboratory abnormalities. Two groups of patients were studied. In Group I there were 34 patients on heroin only which was taken within 24 hours of the ECG. Abnormalities were noted in 55 per cent; QT c prolongation was found in 19 per cent, and significant bradyarrhythmias were found in 19 per cent. In Group II there were 41 patients on methadone with multiple drug abuse; changes were found in 66 per cent. QT c prolongation was noted in 34 per cent, prominent U waves in 32 per cent, and bradyarrhythmias were found in 32 per cent. It is now a well-known fact that the sudden death syndrome in addicts may not be a pharmacologic or dosage-related phenomenon. The existence of conduction, depolarization, and repolarization abnormalities, as well as bradyarrhythmias in a significant number of drug-dependent individuals may play a role in the production and facilitation of lethal arrhythmias and may be the mechanism of the acute fatal reaction.

Myocardial infarction due to coronary atherosclerosis in three young adults with systemic lupus erythematosus

Three patients, 24, 24 and 25 years of age, with systemic lupus erythematosus had signs of myocardial infarction. Two had serial electrocardiographic changes indicative of infarction without any cardiac symptoms. The third patient had clinical evidence of an acute massive myocardial infarction, which was proved at autopsy to be due to coronary atherosclerosis. This case is presented in detail and the association between systemic lupus erythematosus and myocardial infarction is reviewed. It is postulated that the relation between lupus erythematosus and coronary atherosclerosis is more than coincidental.

Arrhythmias in the Wolff-Parkinson-White syndrome

Summary The incidence of the WPW anomaly in adults ranges from 0.1 to 3.1 per thousand and in children from 0.77 to 4.8 per thousand. Acquired heart disease as well as many congenital cardiac defects are associated with the WPW anomaly. Sixty to 70 per cent of patients demonstrating this pattern are males. Arrhythmias occur in about 40 to 80 per cent of patients, and tend to reoccur. The most common arrhythmia is atrial tachycardia. Atrial fibrillation and flutter are also seen. There is a high incidence of rapid ventricular rate with aberration in conduction in response to these arrhythmias (30 per cent). This rapid aberrant ventricular response may be confused with ventricular tachycardia and the criteria for diagnosis are described. Quinidine has been used to terminate the arrhythmias associated with the WPW syndrome. Although the use of digitalis in these arrhythmias has not achieved widespread acceptance, it should be employed as it is in situations not complicated by the WPW anomaly. Combination therapy with digitalis and quinidine has been successful in refractory cases. Electrical cardioversion has also been employed. There should be no deley in instituting therapy since several instances of death have been reported during the acute attacks. Prophylactic use of quinidine is indicated when attacks tend to recur and are severe. The prognosis of the individual patient is affected by the presence or absence of underlying heart disease, age at onset of tachycardia, tendency for recurrence and duration and severity of the single episodes.

Transient Q waves in Prinzmetal's angina

Transient abnormal Q waves were seen in two patients with Prinzmetals angina during episodes of chest pain. The Q waves appeared recurrently while the patients had chest pain and disappeared when it subsided, indicating that Q waves suggestive of myocardial infarction can be seen with severe myocardial ischemia without actual necrosis. We describe these two patients, the various conditions in which transient abnormal Q waves have been reported and the theories offered to explain this electrophysiologic finding.

New Q waves after coronary artery bypass surgery for angina pectoris

Abstract Pre- and postoperative electrocardiograms were evaluated in 44 patients with angina pectoris who underwent single or multiple coronary artery bypass procedures. Two groups were identified: Group A, 37 patients with bypass procedures only, and Group B, 7 patients with bypass procedures and additional surgery (valve replacement in 4 and ventricular resection in 3). Preoperative electrocardiograms showed abnormal Q waves in 14 of 37 patients in Group A and in 3 of 7 patients in Group B. After coronary artery bypass, new Q waves appeared in 11 of 37 patients (30 percent) in Group A, including 1 of 9 (11 percent) with one-vessel disease on preoperative coronary arteriograms, 7 of 20 (35 percent) with, two-vessel disease and 3 of 8 (37.5 percent) with three-vessel disease; new intraventricular conduction abnormalities appeared in 4 of the 37. None of the seven patients in Group B had new Q waves postoperatively, but three had intraventricular conduction abnormalities. There was no correlation between new Q waves and preoperative values for left ventricular end-diastolic pressure. In Group A, new Q waves were demonstrated in 2 of 9 patients (22 percent) with one coronary bypass procedure, 5 of 21 patients (24 percent) with two bypass procedures and 4 of 6 patients (67 percent) with three bypass procedures. The single patient who had four coronary artery bypass procedures had no new Q waves after operation. It is evident that the prevalence of new Q waves was greater in patients who had two- or three-vessel disease by coronary arteriography as well as in those who had three coronary artery bypasses. Postoperative clinical course and mortality were not affected.

Effectiveness of pacemaker treatment in the bradycardia-tachycardia syndrome

Thirty-one patients with the bradycardia-tachycardia syndrome treated with permanent ventricular pacemakers were studied. All were symptomatic before pacemaker insertion, and their symptoms were not controlled with drug therapy alone. Bradycardia and tachycardia associated with multiple arrhythmias were present in all cases; heart rate was less than 40 beats/min in 58 percent of patients and more than 140 beats/min in 71 percent. Conduction abnormalities were present in 61 percent. After insertion of a demand pacemaker, 27 patients (87 percent) were symptom-free for 1 month to 5 years. Although four patients with a normally functioning pacemaker continued to have recurrent arrhythmia, the presence of a pacemaker facilitated further pharmacologic treatment of the disturbance. Pacemaker insertion has been found to be a satisfactory method of treating the symptoms and preventing the recurrence of arrhythmias in patients with the bradycardia-tachycardia syndrome by allowing the use of digitalis and other antiarrhythmic agents.

Prinzmetal's variant angina: A clinical and electrocardiographic study

Abstract Eight patients with “variant” angina pectoris were analyzed for electrocardiographic features before, during, and after chest pain. All patients showed marked concave ST-segment elevations with upright T waves during pain which disappeared with subsidence of pain. Ventricular dysrhythmias were noted in four patients. Three had ventricular tachycardia and one had an idioventricular rhythm. In addition, one patient had a transient Mobitz II atrioventricular block. The electrocardiogram during pain at the time of right ventricular pacing in one patient revealed elevated ST-segments with upright T waves in the previously involved leads. Coronary arteriography in four patients revealed an isolated single lesion in three and normal coronary vessels in the other. The possible basis of the electrocardiographic findings is discussed.

Comparison of infective endocarditis in drug addicts and nondrug users

All cases admitted over a 2-year period with the diagnosis of infective endocarditis were reviewed. Two groups were studied: Group 1—known drug addicts; and Group 2—persons with no history of drug use or cardiac disease before the onset of endocarditis. Group 1 consisted of 13 drug addicts with 17 admissions for endocarditis. Fifty-two percent used heroin, 30 percent amphetamines and 18 percent used both drugs. The infective organism was identified as Staphylococcus aureus in 64 percent, Candida in 17 percent and enterococcus in 11 percent. Respiratory symptoms and pulmonary infiltrates were seen on admission in 70 percent. Aortic valve involvement, either alone or in combination with mitral valve involvement, was seen in 11 instances (65 percent), isolated mitral insufficiency in 5 (29 percent). Complications were seen in 14 (82 percent). Surgical intervention for intractable cardiac failure was performed in 3 patients without operative mortality. Of the 10 patients treated medically, 3 died. Group 2, composed of 7 nondrug users differed from Group 1 in the following variables: (1) greater mean age (52.7 years compared to 27.4 years); (2) longer duration of symptoms, more than 1 week in 86 percent vs. 1 week or less in 94 percent of drug users, and (3) an absence of respiratory symptoms on admission. Surgical intervention was necessary in two patients. There were no deaths. Infective endocarditis in drug users remains a serious disease that may respond to prompt medical and surgical therapy.

Disappearance of abnormal Q waves after aortocoronary bypass surgery

Sixty-one patients were selected from 100 consecutive patients under-going aortocoronary artery bypass. The number of vessels diseased as defined by coronary arteriography and the number of bypass grafts were recorded. Review of the preoperative electrocardiograms showed an infarct pattern in 26 of the 61 patients and analysis of the postoperative electrocardiograms revealed loss of abnormal Q waves in 3 of the 26. The pre- and postoperative clinical course of these three patients is analyzed and the extent of their coronary artery disease and number of bypass grafts compared with those of the 23 patients who had persistence of the infarction pattern and the 17 patients who manifested new Q waves. Possible explanations for the disappearance of abnormal Q waves are discussed.