Atrial fibrillation: the most common arrhythmia.

Atrial fibrillation is the most common sustained arrhythmia, increases with age, and presents with a wide spectrum of symptoms and severity Paroxysmal, persistent, and permanent forms require very individualized approaches to management. New information about electrical and anatomic remodeling emphasizes the importance of time-related thrombogenicity and progressive interference with mechanical function of the atria and ventricles. The most important aspect of diagnosis is risk stratification with respect to risk of thromboembolism.

Implantable cardioverter defibrillator infection causing constrictive pericarditis.

A case of severe constrictive pericarditis resulting from an indolent Pseudomonas aeruginosa infection of the automatic internal cardiac defibrillator is described. Total explanation of the device was attempted after nine months but was unsuccessful because of dense adhesions under the patch electrodes. The patient subsequently developed clinical and hemodynamic findings of constrictive pericarditis and a second desperate attempt to remove the patches resulted in operative death.

Intraoperative identification of a radiofrequency lesion allowing validation of catheter mapping of ventricular tachycardia with a computerized balloon mapping system.

Radiofrequency current was utilized to mark the anatomic location of earliest endocardial activation during catheter mapping of ventricular tachycardia. Intraoperative identification of the radiofrequency lesion allowed validation that the site of earliest endocardial activation determined by a catheter mapping study was the same as assessed by a computerized balloon mapping system. Radiofrequency current may be a useful method of marking areas of endocardium thought to be potential sites for ablative surgery as well as allowing correlation between different mapping techniques.

Chlorobenzoate catabolic transposon Tn5271 is a composite class I element with flanking class II insertion sequences.

The structure of a transposon specifying the biodegradation of chlorobenzoate contaminants is described. Tn5271 is a 17-kilobase (kb) transposon that resides in the plasmid or chromosome of Alcaligenes sp. strain BR60 and allows this organism to grow on 3- and 4-chlorobenzoate.

Long-term results of antitachycardia pacing in patients with supraventricular tachycardia.

Between 1979 and 1984 the Cybertach-60, (Intermedics, Inc. Model 262-01), a programmable, automatic antitachycardia pacemaker was implanted in 11 patients who had drug-refractory supraventricular tachycardia (SVT). The patients have been followed for a total of 64-108 (mean 84 months).

Role of invasive electrophysiologic testing in the management of life-threatening ventricular arrhythmias.

Electrophysiologic studies are indicated in patients with sustained paroxysmal ventricular tachycardia, ventricular fibrillation or aborted sudden death. These studies allow determination of mechanism and reproducibility of initiation as well as pacing termination of ventricular tachycardia, against which the effects of pharmacologic or nonpharmacologic therapies can be tested. Such studies are also indicated in certain patients with syncope in whom a strong suspicion exists for an arrhythmic cause.

Significant variability in the mode of ventricular tachycardia induction and its implications for interpretation of acute drug testing.

Fifty-four patients with previous myocardial infarction and sustained ventricular tachycardia on fibrillation underwent two electrophysiologic studies in the drug-free state within 72 hours. Although the concordance of overall ventricular tachycardia induction over the 2 days was good (87% of patients), there was variability in the number of extrastimuli needed to induce sustained ventricular tachycardia on each day in 60% of patients. Of those in whom ventricular tachycardia was inducible on both days, 40% required additional extrastimuli and 20% required fewer extrastimuli.

Amiodarone pulmonary toxicity: prospective evaluation of serial pulmonary function tests.

Pulmonary toxicity developed in 15 (17%) of 89 patients treated with amiodarone during a follow-up period of 2 weeks to 54 (mean 20 +/- 15) months. Prospective evaluation of serial pulmonary function tests in 67 patients demonstrated both a significant decrease from baseline in three of six variables in patients with toxicity at the time of diagnosis and a significant difference compared with the same variables in patients without toxicity. The most significant of these was the diffusing capacity for carbon monoxide (DLCO).

Surgical treatment of right atrial focal tachycardia in adults.

Although successful operative treatment of atrial focal tachycardia has been reported in children, there are only isolated reports of surgical treatment of this arrhythmia in adults. In this case series of eight patients (aged 10 to 53 years) with drug-resistant right atrial focal tachycardia, results of electrophysiologic studies, surgical techniques and long-term follow-up are described. Atrial focal tachycardia was reproduced during electrophysiologic study, and endocardial mapping localized the earliest onset of atrial activation in the right atrium in all patients.

Cumulative effects of amiodarone on inducibility of ventricular tachycardia: implications for electrophysiological testing.

To determine whether the slow onset of action of amiodarone might result in a delayed effect on the inducibility of sustained ventricular arrhythmias, 45 patients with ischemic heart disease and inducible sustained monomorphic ventricular tachycardia were prospectively studied. Each patient had at least one initial repeat study on amiodarone and those with persistently inducible arrhythmias were rescheduled for further studies over the following 24 weeks. After 2-3 weeks of amiodarone therapy, nine patients no longer had inducible tachycardias, and tachycardia in another eight patients (18%) later became noninducible.

Electrophysiology of Ethmozine (moricizine HCl) for ventricular tachycardia.

Moricizine HCl, an antiarrhythmic phenothiazine drug, was investigated for its efficacy against ventricular tachycardia (VT) in a group of 60 patients from 8 institutions using electrophysiologic testing before and after oral administration. Moricizine HCl significantly prolonged PR, QRS, AH and HV intervals and cycle length for atrioventricular nodal block, but had minimal or no effect on repolarization or cardiac refractory periods. Induction of sustained VT (in 33 patients) and nonsustained VT (in 14 patients) occurred at baseline.

Implanted atrial pacemakers for paroxysmal atrial flutter. Long-term efficacy.

Five patients with drug-resistant paroxysmal atrial flutter received permanent burst atrial pacemakers for the treatment of tachycardia. All patients had extensive electrophysiologic evaluations to determine the safety and efficacy of atrial pacing. The absence of prolonged spontaneous or electrically induced atrial fibrillation was also documented in all patients.

Spontaneous arrhythmia detected on ambulatory electrocardiographic recording lacks precision in predicting inducibility of ventricular tachycardia during electrophysiologic study.

This study investigates the relation of spontaneous ventricular arrhythmia on ambulatory electrocardiographic (ECG) monitoring to the subsequent inducibility of ventricular tachycardia during programmed electrical stimulation. Eighty patients (65 men, 15 women), whose mean age was 58 years, presented with one of the following: sustained ventricular tachycardia (n = 54); sudden death requiring resuscitation (n = 4); ventricular fibrillation (n = 11); or syncope thought to be of cardiac origin (n = 11). All patients had 24 hour ambulatory electrocardiograms and programmed electrical stimulation while receiving no antiarrhythmic therapy.

Surgical treatment of supraventricular arrhythmias. Results in 67 patients.

Over 6 years, recurrent drug-refractory supraventricular arrhythmias were treated by electrophysiologically guided surgical procedures in 67 patients. There were 57 patients, age 10-72 years, with accessory pathways who had 61 operations. The perioperative mortality rate was 3.

Prospective comparison of right and left ventricular stimulation for induction of sustained ventricular tachycardia.

Thirty-eight patients who had sustained monomorphic ventricular tachycardia (VT) or sudden cardiac death underwent programmed ventricular stimulation. To assess the relative efficacy of right and left ventricular (RV and LV) stimulation, a tandem protocol with 1 to 4 extrastimuli and burst pacing was used. Each step of the protocol was performed in a rotating sequence at the RV apex, basal RV septum and LV apex.

Prevalence of hypercholesterolaemia in young Afrikaners with myocardial infarction. Ischaemic heart disease risk factors.

Ischaemic heart disease (IHD) risk factors, with particular reference to familial hypercholesterolaemia (FH), were studied in 39 male and 12 female Afrikaners aged 55 years or under in an intensive care unit immediately after an acute myocardial infarction and in the survivors at about 3 months after the infarct. Two major risk factors were found. Firstly, about three-quarters of both male and female patients smoked more than 15 cigarettes daily.

Prevalence of hypercholesterolaemia in young Afrikaners undergoing coronary artery bypass surgery. Ischaemic heart disease risk factors.

Ischaemic heart disease risk factors, with particular reference to familial hypercholesterolaemia, were studied in 47 male and 6 female Afrikaners, aged 55 years and under, admitted to hospital for coronary bypass surgery. The outstanding feature in this group with severe coronary atherosclerosis demonstrated angiographically was that about half had severe hypercholesterolaemia (greater than or equal to 8.5 mmol/l), and that of the severely hypercholesterolaemic patients about half again had familial hypercholesterolaemia (FH).

Two different patterns of entrainment of ventricular tachycardia.

In a patient with two morphologic forms of ventricular tachycardia, rapid pacing from different ventricular sites produced two distinctively different patterns of entrainment. Pacing from sites contralateral to the site of emergence of ventricular tachycardia caused progressive fusion. Following pacing, the interval (return interval) between the first tachycardia beat (return beat) and the preceding beat was equal to the pacing cycle length.

Effects of personal, environmental and occupational factors on ischaemic heart disease in white miners in South Africa.

The objective of this study was to determine which personal, environmental and occupational factors were associated with risk of non-fatal ischaemic heart disease in a group of 3930 white underground miners born between 1916 and 1930. Evidence of previous myocardial infarction, based on their electrocardiograms and answers to the Rose questionnaire, was found in 179 men who were taken as the cases of interest. Because of difficulties in coding the occupational histories of all available miners, a representative sample of the remaining 'non-infarct' miners was drawn as a reference sample.

Classic and concealed entrainment of typical and atypical atrial flutter.

Classic and concealed entrainment was demonstrated in a patient with spontaneous typical atrial flutter and pacing-induced atypical atrial flutter. The form of entrainment manifested depended on the site of pacing and the direction of tachycardia as determined by endocardial mapping.

Comparison of mortality rates for cancer in black adults--1970 v. 1980.

Mortality rates (MRs) for cancer in black men and women, aged 25-74 years, in the 34 'selected' (urban) magisterial districts were calculated for 1980 and compared with the MRs for cancer in 1970. All MRs were age-adjusted to the age distribution of the white population in 1970 to enable valid comparisons to be made. A notable feature was the increase in MRs for cancer of the oesophagus and cancer of the lungs over the period.

Mortality of middle aged white South African gold miners.

A cohort of 3971 white miners in South Africa, born between 1 January 1916 and 31 December 1930 who were alive on 1 January 1970 and currently working in the East Rand-Central Rand-West Rand mining areas, was followed up for nine years, when the 3426 survivors were aged from 48 to 62. Fifteen (0.4%) had been lost to view and 530 had died (13.

Mortality rates of black infants in Soweto compared with other regions of South Africa.

Mortality rates (MRs)/100,000 for 1980 were calculated for black infants under 1 year of age for all causes of death and for the leading causes of death--gastro-enteritis, ill-defined causes, perinatal conditions, and the pneumonias--in three regions, Soweto, the 34 'selected' magisterial districts (all urban) and the rural areas in the RSA. The results showed a low MR for all causes of death (2813,7/100,000) and a low ranking of gastro-enteritis (third) in Soweto. In contrast the infant health situation in the 34 'selected' magisterial districts showed an MR from all causes of death which was three times higher (8,594/100,000) than in Soweto and gastro-enteritis was the leading cause of death with an MR 10 times higher than in Soweto.

Electrophysiologic evaluation of pirmenol for sustained ventricular tachycardia secondary to coronary artery disease.

The efficacy and electrophysiologic effects of pirmenol were evaluated in 21 patients with a history of sustained ventricular tachycardia (VT) and coronary artery disease. Intravenous pirmenol (0.7- to 1.