Jacob Agmon

Polymorphous ventricular tachycardia: Clinical features and treatment

Thirty-four cases of ventricular tachyarrhythmia characterized by polymorphy of the QRS complexes with changing R-R intervals and a heart rate of 150 to 300 beats/min, termed polymorphous ventricular tachycardia, are described. The factors involved in the appearance of this arrhythmia were the administration of antiarrhythmic drugs (quinidine 22 patients, procainamide 5 patients, ajmaline 1 patient), antianginal drugs (prenylamine [Synadrin] 4 patients) and antidepressant drugs (thioridazine 1 patient). Twenty-one patients were treated for premature ventricular complexes, three for chronic recurrent ventricular tachycardia, six for atrial flutter and fibrillation, three for anginal pain and one patient for mental depression. All patients except one had a drug-induced prolonged corrected Q-T interval before the appearance of polymorphous ventricular tachycardia. Most of the patients with this arrhythmia were considered to have severe myocardial disease. Lidocaine and electric cardioversion were administered to all patients, but were effective only in seven patients whose tachycardia occurred in short, single episodes. The most effective treatment (17 patients) was temporary ventricular pacing at rates ranging from 100 to 140 beats/min. Intravenous isoproterenol proved to be successful in another 10 cases. It is concluded that patients with severe myocardial involvement receiving antiarrhythmic drugs for premature ventricular complexes, especially the multiform variety, are at high risk for the development of polymorphous ventricular tachycardia.

Cerebrovascular accident complicating acute myocardial infarction: Incidence, clinical significance, and short-long-term mortality rates

Abstract purpose: The purpose of this study was to report the incidence, the antecedents, and the clinical significance of clinically recognized cerebrovascular accidents or transient ischemic attacks (CVA-TIA) complicating acute myocardial infarction. patients and methods: During 1981 to 1983, a secondary prevention study with nifedipine (SPRINT) was conducted in 14 hospitals in Israel among 2,276 survivors of acute myocardial infarction. During the study, demographic, historical, and medical data were collected on special forms for all patients with diagnosed acute myocardial infarction in 13 of these 14 hospitals (the SPRINT registry, n=5,839). Mortality followup was completed for 99% of hospital survivors for a mean follow-up of 5.5 years (range: 4.5 to 7 years). results: The incidence of CVA-TIA was 0.9% (54 of 5,839). The latter rate increased significantly only with age, from 0.4% among patients up to 59 years old to 1.6% among those aged greater than or equal to 70 years. Multivariate analysis identified age, congestive heart failure, and history of stroke as predictors of CVA-TIA during the acute phase of myocardial infarction. Patients with CVA-TIA exhibited a complicated hospital course, with a 15-day mortality rate of 41%. Subsequent mortality rates in survivors at 1 and 5 years were 34% and 59%, respectively. Rates at the same time points in patients without CVA-TIA were 16%,11%, and 29% (p conclusion: In this large cohort of consecutive patients with myocardial infarction, CVATIA was a relatively infrequent complication of acute myocardial infarction. Factors independently favoring the occurrence of CVA-TIA were old age, previous CVA, and congestive heart failure. CVA-TIA occurring during acute myocardial infarction independently increased the risk of early death threefold as well as the risk of long-term mortality in early-phase survivors (2.5-fold).

Transient right axis deviation during acute anterior wall infarction or ischemia: electrocardiographic and angiographic correlation.

Eleven patients, three with acute anterior myocardial infarction and eight with anterior ischemia, who developed transient right axis deviation with a left posterior hemiblock pattern during the acute phase of myocardial infarction or ischemia are described (study group). A correlation between their electrocardiographic pattern and the angiographic findings was made. The arteriographic findings were compared with those of a group of 24 patients with acute anterior myocardial infarction or ischemia without transient right axis deviation (control group). The main electrocardiographic characteristics of the right axis deviation pattern were: an average shift of the mean frontal axis to the right of 42 degrees (10 degrees to 94 degrees); increased voltage of R waves in leads II, III and a VF and appearance of small Q waves or decreased voltage of Q waves if previously present in the same leads; decreased voltage of R waves and appearance of deep S waves in lead aVL; and inverted T waves and isoelectric ST segments in leads II, III and aVF. Coronary angiography revealed that the study group had a higher incidence of significant right coronary artery obstruction and collateral circulation between the left coronary system and the posterior descending artery than did the control group (100 versus 25% and 73 versus 0%, respectively; p less than 0.01). There were no differences between the groups regarding left anterior descending and circumflex artery disease.(ABSTRACT TRUNCATED AT 250 WORDS)

The Effect of Glucagon on Arrhythmias Due to Digitalis Toxicity

Abstract The effect of glucagon on arrhythmias produced by digitalis (ouabain) and on ventricular automaticity was studied in 36 dogs. Glucagon abolished the arrhythmias in 26 dogs (72 percent), primarily by producing a sinus tachycardia with 1:1 ventricular response, thereby competing with and suppressing the ectopic rhythm. After administration of glucagon in the normal heart, ventricular automaticity was generally unchanged. During digitalis toxicity, glucagon had either not changed or decreased ventricular automaticity, the decrement in ventricular automaticity showing poor correlation with this agents antiarrhythmic effect. Glucagon also induced an immediate rise, then a fall in serum potassium levels. It is concluded that a multiplicity of factors—enhanced automaticity of the sinoatrial node, improved atrioventricular conduction, changes in potassium levels and, at times, slight lowering of ventricular automaticity—all contribute to the antiarrhythmic capabilities of glucagon.

DELETERIOUS EFFECTS OF INTRAVENOUS VERAPAMIL IN WOLFF-PARKINSON-WHITE PATIENTS AND ATRIAL FIBRILLATION

SummaryThree patients presented to the emergency room with atrial fibrillation and fast ventricular response with wide preexcited QRS complexes (Wolff-Parkinson-White syndrome). All three patients received intravenous verapamil (5–10mg). The first patient developed ventricular fibrillation requiring several defibrillations; the second patient developed severe hemodynamic deterioration requiring urgent cardioversion; in the third patient a marked increment in the ventricular response was noted, however, there was no hemodynamic impairment.Verapamil may cause detrimental results when given to patients with the Wolff-Parkinson-White syndrome and atrial fibrillation. Its administration should therefore be considered as an absolute contraindication in these patients.

Natural course of electrocardiographic components and stages in the first twelve hours of acute myocardial infarction

Time course evolution of R, Q, T and ST components of the electrocardiogram during the first 12 hours of an acute myocardial infarction was studied. A comparison between anterior-extensive and anteroseptal wall infarctions (anterior group), and inferior-extensive and inferior wall infarction (inferior group) showed appearance of significant Q waves within two hours in both groups. R wave loss was nearly a mirror image of Q wave development in both groups. T waves became negative and ST more isoelectric earlier in the inferior than in the anterior group. When combined variations of the four electrocardiographic components were analyzed, four stages of acute infarction were delineated. Stage I--tall R, no Q, ST elevation and positive T; Stage II--significant Q wave appearance; Stage III--negativity of T waves; and Stage IV--ST isoelectric. The inferior group reached stages III-IV within 12 hours; the anterior group remained mostly in stage II. An early appearance of Q waves correlated well with rapid progression to stages III-IV within 12 hours in both infarction groups.

Ventricular Fibrillation in a Patient with ‘Silent’ Mitral Valve Prolapse

A patient with clinically silent mitral valve prolapse experienced an episode of out-of-hospital cardiac arrest due to ventricular fibrillation. This arrhythmia was easily replicated in the electrophysiology laboratory and despite treatment with amiodarone alone and amiodarone in combination with propranolol. Amiodarone in combination with quinidine prevented the induction of ventricular fibrillation and proved effective during a 3-year follow-up period. Even though a clear-cut relationship between the arrhythmias and mitral valve prolapse cannot be established, this case suggests that sudden death can occur in patients with mitral valve prolapse but without the known risk factors for the development of sudden death.

Effect of Metaraminol During Acute Inferior Wall Myocardial Infarction Accompanied by Hypotension: Preliminary Study

This study was designed to evaluate the effects of metaraminol (Aramine) in six patients with evolving acute inferior wall myocardial infarction accompanied by hypotension and warm limbs. There were 16 episodes of acute inferior wall ischemia, and the response to therapy was judged by evaluating blood pressure and ST segment and T wave abnormalities. Three patients received intravenous isosorbide dinitrate and two received streptokinase as the initial therapy. The mean ST segment elevation was significantly reduced (from 4.94 +/- 1 to 0.5 +/- 0.7 [p less than 0.0001]) after metaraminol infusion was initiated. The average T wave height also decreased (from 6.8 +/- 2 to -1.3 +/- 2.5 mm [p less than 0.0005]). The average heart rate decreased from 82 +/- 11 to 69 +/- 9 beats/min (p less than 0.05) and the mean arterial blood pressure increased from 81 +/- 12 mm Hg before metaraminol treatment to 126 +/- 8 mm Hg after treatment. All these changes occurred within a few minutes after metaraminol therapy was instituted. In 12 episodes, accelerated idioventricular rhythm appeared concomitantly with the resolution of ST segment elevation. Coronary angiography performed between 4 and 10 days after admission demonstrated significant obstruction in all infarct-related arteries, but none was totally occluded. Left ventricular function was normal in three patients and slightly hypokinetic in the inferior wall in two. These results indicate that in a selected group of patients with acute inferior myocardial infarction, metaraminol administration (in certain hemodynamic circumstances) can alleviate acute ischemia within a few minutes and thereby reduce ischemic injury.

Three-vessel coronary artery spasm in a patient with variant angina and normal coronary arteries

Variant angina with two or more electrocardiographic or angiographic localizations has seldom been reported [1-4]. We present a case of variant angina pectoris and normal coronary arteries with three different and independent electrocardiographic localizations.

Deep inspiration induced sinus arrest. An unusual manifestation in a patient with the sick sinus syndrome

In a patient with the sick sinus syndrome and near syncope a prolonged sinus pause was documented and reproduced thereafter during sustained deep inspiration. Administration of intravenous atropine abolished this phenomenon, most probably indicating a hyperresponsiveness of the sinus node and AV junction to a vagotonic reflex.