PubMed Health⌕ Search

Biomedical subjects

L E Rosenfeld

Publications and source records attributed to L E Rosenfeld.

At least 19 recordsLinked to original sources

Inappropriate sensing of atrial stimuli in patients with third-generation defibrillators and DDD pacemakers.

Although the problem of ICD sensing of paced ventricular stimuli has been resolved by incorporation of VVI pacing into current ICDs, many patients required separate DDD pacemakers. We report a problematic PM-ICD interaction: the inability to prevent sensing of paced atrial stimuli ("atrial sensing") leading to double-counting in DDD-PM-requiring patients with transvenous (TV) ICDs with aggressive autogain sensing (CPI Ventak PRxII or III). Four of eight patients receiving both transvenous DDD PMs and ICDs (CPI Endotak lead, at the RV apex), had atrial sensing, leading to double counting, despite intraoperative testing of multiple atrial locations with an active fixation lead. Five patients had a PRxII/III ICD, four with atrial sensing (80%), and three a PRx without atrial sensing. Patients with atrial sensing were not distinguished by any clinical or device related variable. In patients with atrial sensing (all with heart block), the PM was programmed to VDD mode. No patient has received inappropriate therapy or failed to sense VF in follow-up. In many patients with TV ICDs who required DDD pacing, no atrial position can be found without ICD sensing of atrial stimuli. While in patients with heart block this problem can be circumvented by programming to the VDD mode, in patients with sinus incompetence it may only be resolved by the combination ICD-DDD PM, currently in development.

Aged↗

Amiodarone induced pulmonary fibrosis in infancy.

We report a case of pulmonary fibrosis in an infant receiving amiodarone for treatment of intractable atrioventricular reentrant tachycardia secondary to Wolff-Parkinson-White syndrome. At 9 months, a screening chest radiograph showed a diffuse interstitial infiltrate in an asymptomatic, thriving infant. Amiodarone was discontinued and the pulmonary fibrosis resolved gradually over 6 months. This case documents the first report of amiodarone induced pulmonary fibrosis in the pediatric age group. We speculate that as amiodarone is used more frequently to manage pediatric arrhythmias, pulmonary fibrosis, a known complication of this antiarrhythmia in adults may be seen with increasing frequency in children.

Adrenergic beta-Antagonists↗

Quality-of-life in patients receiving implantable cardioverter defibrillators at or before age 40.

As the use of ICDs increases, more young patients will be eligible to receive these devices. Such patients may have different concerns than older patients who more commonly receive ICDs. We investigated quality-of-life issues in patients followed by the Yale electrophysiology service who were < or = 40 years old (mean = 28) at the time of ICD implant. Mean time since ICD placement was 3.3 years. Each patient received a modified SF-36 health questionnaire; 16 (88%) of 18 responded. Nine were women; ten were married. The highest education level attained was high school for 6 (37%), and college or beyond for 10 (63%). Ten patients were employed; eight held the same job before and after ICD placement. Four women conceived after ICD implantation; one experienced ICD discharge during pregnancy. All delivered healthy infants. All patients felt their health was good to excellent, with 6 (38%) reporting an improvement in health since ICD placement. All felt capable of performing the activities of daily living, while 68% engaged freely in moderate physical activities. All patients felt they were average to very attractive. However, 63% worried about how their clothes fit with the ICD. Three quarters of the patients felt the ICD interfered with social interactions, while 50% were concerned about sexual encounters. Thus, even though these young patients have body image concerns and may limit their activities to some degree, they are productive, active members of society who have benefitted from ICD placement.

Adolescent↗

Thromboembolic complications after Fontan operations.

BACKGROUND: Despite the increasing recognition of thromboembolic complications of the Fontan procedure, data characterizing such events are limited. The total cavopulmonary connection is believed to be less prone to this complication than other modifications of Fontan operations. We examined our experience with thromboembolism after Fontan operations to better characterize these events and their relation to the type of Fontan operation performed. METHODS AND RESULTS: We retrospectively identified 70 patients who underwent a Fontan operation between January 1978 and March 1994. Patients were divided into three groups: (1) total cavopulmonary connection, (2) atriopulmonary connection, and (3) conduit interposition. Fourteen patients (20%) developed a thromboembolic complication during a mean (+/- SD) follow-up of 5.2 +/- 4.7 years. The rate of thrombosis was similar in each group. The time from Fontan operation to thrombosis averaged 6.1 +/- 5.0 years. The overall rate of thromboembolic events was 3.9 per 100 patient-years. Twelve of the 14 thrombi were located within the venous circulation, 1 was in the left ventricle, and the location of 1 was undetermined. Six of the patients (43%) were asymptomatic, 3 (21%) presented with cerebrovascular events, and 5 (36%) presented with other symptoms. Thromboembolic events occurred from the perioperative period to 15 years after surgery. CONCLUSIONS: Thromboembolic complications occur frequently after the Fontan operation and its modifications and are a cause of significant morbidity. The time of presentation varies greatly. The rate of thrombosis appears to be similar in all modifications of the Fontan operation.

Adolescent↗

Double sequential external shocks for refractory ventricular fibrillation.

OBJECTIVES: A technique for terminating refractory ventricular fibrillation is described. BACKGROUND: Refractory ventricular fibrillation can occur in up to 0.1% of electrophysiologic studies. Animal studies have shown that rapid sequential shocks may reduce ventricular fibrillation threshold. METHODS: Five patients of 2,990 consecutive patients in a 3-year period experienced refractory ventricular fibrillation during 5,450 routine electrophysiologic studies. Multiple shocks were delivered by means of a single defibrillator. Double sequential shocks were delivered externally 0.5 to 4.5 s apart by means of two defibrillators with separate pairs of electrodes. RESULTS: In all patients, standard defibrillation was unsuccessful, but all were successfully resuscitated using the double sequential shocks. CONCLUSIONS: This report stresses the importance of an additional defibrillator being readily available during electrophysiologic testing. This technique of rapid, double sequential external shocks may have general applicability, providing a simple and potentially lifesaving approach to refractory ventricular fibrillation.

Electric Countershock↗

Radiofrequency ablation of an accessory pathway in a patient with corrected Ebstein's anomaly.

Ebstein's anomaly of the tricuspid valve has a known association with the Wolff-Parkinson-White syndrome. Radiofrequency ablation has become the treatment of choice for the latter, but there have been no reports of the feasibility of this procedure after tricuspid valve replacement. We present a patient who first exhibited evidence of intermittent preexcitation and associated symptomatic arrhythmia 9 years after tricuspid valve replacement for Ebstein's anomaly, and describe the challenges posed by this case.

Adult↗

Ectopic atrial tachycardia in utero.

BACKGROUND: The antenatal diagnosis of fetal arrhythmias helps direct medical management, which may include intrauterine therapy. Ectopic atrial tachycardia is an unusual arrhythmia in children, and we know of no previous reports of antenatal diagnosis of this particular arrhythmia. CASE: The diagnosis of fetal ectopic atrial tachycardia was suggested by the monitor tracing during labor and was subsequently confirmed by the postpartum behavior of the arrhythmia and its electrocardiographic characteristics. CONCLUSION: Ectopic atrial tachycardia, although uncommon, should be considered in the differential diagnosis of fetal tachycardias. The fetal monitor tracing may be useful in making this diagnosis antenatally, which may help to direct management both before and after birth.

Adult↗

The diagnosis and management of cardiac arrhythmias in the neonatal period.

While cardiac arrhythmias are relatively uncommon in the neonatal period, their diagnosis and therapy may be challenging. Careful analysis of the ECG both during and after termination of an arrhythmia is essential in making the correct diagnosis. A knowledge of associated conditions may be especially helpful in recognizing and dealing with rhythm problems. With an increased understanding of arrhythmia mechanisms, new drugs and therapeutic techniques have increased our ability to effectively treat, and in fact, to cure, these infants.

Arrhythmias, Cardiac↗

Determinants of the hemodynamic consequence to sustained ventricular arrhythmias after a single myocardial infarction.

Patients who have sustained ventricular arrhythmias after myocardial infarction present with either a cardiac arrest or with hemodynamically stable sustained ventricular tachycardia. Recent reports have suggested a different electrophysiologic milieu in these two patient groups and a higher incidence of cardiac arrest in patients with a history of more than one myocardial infarction. No studies have examined patients with only a single previous myocardial infarction. To assess the determinants of the hemodynamic consequence of sustained ventricular arrhythmias more than 3 days after a single myocardial infarction, 82 patients who were resuscitated from arrhythmic cardiac arrest (CA group, 40 patients) or who had hemodynamically stable sustained ventricular tachycardia (No CA group, 42 patients) were examined. Patients in both groups had similar global left ventricular ejection fractions (mean +/- SD; 30% +/- 12% vs 27% +/- 12%; p = NS), proportion of patients with anterior wall infarctions as compared with the proportion of patients with inferior wall infarctions (55% vs 50%; p = NS), time from infarction to arrhythmia development, severity of coronary artery disease, and the proportion of patients with congestive heart failure or bundle branch block. Patients who presented without cardiac arrest, however, more frequently had left ventricular aneurysms (58% vs 28%; p = 0.005). Sixty-seven patients underwent baseline drug-free electrophysiologic studies. Sustained ventricular tachycardia was induced in 79% of patients in the CA group and 85% of patients in the No CA group (p = NS).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

Antiarrhythmic drug exacerbation of ventricular tachycardia inducibility during electrophysiologic study.

Most studies examining antiarrhythmic drug exacerbation of ventricular arrhythmias have been performed in patients in whom clinical proarrhythmia developed. The clinical significance and predictors of antiarrhythmic drug exacerbation of inducible ventricular arrhythmias during electrophysiologic study have received less attention. Accordingly, a consecutive number of patients undergoing electrophysiologic study for evaluation of ventricular arrhythmias (but who had no history of clinical proarrhythmia) were prospectively examined. Drug-induced exacerbation was defined as no inducible ventricular tachycardia in the baseline drug-free state that increased to inducible nonsustained or sustained ventricular tachycardia, or inducible nonsustained ventricular tachycardia at baseline that increased to inducible sustained ventricular tachycardia. After administration of primarily type IA antiarrhythmic agents (procainamide and quinidine in 97% of the patients), patients were considered drug test negative (n = 80) when they had no increase in inducible ventricular tachycardia, and patients were considered drug test positive (n = 16) when they had exacerbation of inducible arrhythmias. The drug test-positive group's clinical characteristics differed markedly from those of the drug test-negative group. Compared with the drug test-negative group, the drug test-positive group had reduced (less than 40%) left ventricular ejection fractions (80% vs 39%, p = 0.005) and higher prevalences of myocardial infarctions (81% vs 35%, p = 0.027), left ventricular aneurysms (27% vs 5%, p = 0.026), and bundle branch blocks (53% vs 16%, p = 0.005). Thus exacerbation of ventricular tachycardia induction after antiarrhythmic agent administration was most common in patients with significant organic heart disease. The drug test-positive group was more frequently treated with antiarrhythmic therapy than was the drug test-negative group.(ABSTRACT TRUNCATED AT 250 WORDS)

Anti-Arrhythmia Agents↗

Strategies in the surgical treatment of malignant ventricular arrhythmias. An 8-year experience.

Introduction of the automatic implantable cardioverter defibrillator (AICD) has dramatically affected the surgical treatment of malignant ventricular tachyarrhythmias. The authors continue to perform electrophysiologically directed subendocardial resection (SER) of left ventricular (LV) scars in selected patients, and we revascularize (CABG) those patients undergoing AICD implantation who have significant myocardial ischemia. In an attempt to define the optimal role of each procedure, this report analyzes our 8-year experience with 348 consecutive patients treated surgically for these arrhythmias (SER since 1983 and AICD since 1986). All patients undergoing SER had organized ventricular tachycardia (VT) as a result of myocardial infarction, and most had LV aneurysms; of those undergoing AICD or AICD/CABG, 60% had VT, 15% had ventricular fibrillation, and 25% had both or were noninducible. The thirty-day mortality rate was 1.5% (3/197) for AICD, 5.4% (5/93) for AICD/CABG, and 8.6% (5/58) for SER; these mortality figures are not significant different. Late deaths in all groups were predominantly due to congestive heart failure, and actuarial survival as well as freedom from sudden death was similar between the groups at 4 years. Recurrent VT occurred in 167 of 282 (59%) of long-term survivors of AICD or AICD/CABG during follow-up and in nine of 53 (17%) of those with SER. Forty-eight per cent of survivors of AICD or AICD/CABG required antiarrhythmic medications, whereas only 11% of those with SER required antiarrhythmics. Long-term survival in each group is much higher than that reported for comparable patients with severe LV dysfunction treated medically. In those patients with organized VT and LV aneurysm who are judged able to survive the procedure, SER offers a high likelihood of cure rather than simple prevention of sudden death.

Actuarial Analysis↗

Advances in syncope: a combined approach utilizing head-up tilt testing and electrophysiologic evaluation.

The electrophysiological evaluation of syncope of unknown origin yields a diagnosis in approximately 40% of patients. In the presence of structural heart disease ventricular tachycardia is the most common etiology accounting for 20% of cases. Over the past several years head-up tilt table testing with isoproterenol provocation has highlighted the syndrome of neurocardiogenic syncope. This syndrome accounts for an additional 30-40% of patients with syncope. There is compelling evidence that this syndrome involves the Bezold-Jarisch reflex with excessive stimulation of ventricular mechanoreceptors (C-fibers) located predominantly in the inferoposterior portion of the heart. Tilt table testing is now an established tool both for diagnosis of this syndrome and for guiding therapy with beta blockers, disopyramide, theophylline, or alpha-agonists. Tilt table testing combined with invasive electrophysiological testing significantly increases the diagnostic yield in the evaluation of syncope.

Arrhythmias, Cardiac↗

Tachycardias of right ventricular origin.

Ventricular tachycardia arising from the right ventricle usually has a left bundle branch morphology and occurs in a variety of disorders. Uhl's anomaly and right ventricular dysplasia may represent a spectrum of one disorder and are a cause of right heart dilatation, failure, and premature sudden death due to ventricular arrhythmias. Familial forms of the disorder may account for focal clustering in some geographic areas. Management should involve aggressive stratification of arrhythmia risk and may include medical, surgical, or device therapy. In contrast, the syndrome of right ventricular outflow tract tachycardia, including nonischemic exercise-induced and repetitive monomorphic ventricular tachycardia, is a more benign entity. Management often involves beta- and calcium channel blocking drugs or type IC antiarrhythmic drugs. Catheter ablation of the arrhythmia focus in the right ventricular outflow tract has been used in selected patients. In this syndrome the right ventricle is normal, and noninvasive testing as well as electrophysiologic studies can be helpful in distinguishing it from the more malignant right ventricular dysplasia. Ventricular arrhythmias may also be seen after right ventricular incision, as in surgical repair of tetralogy of Fallot and ventricular septal defects. Significant ventricular ectopy associated with an abnormal right ventricle (enlarged or depressed systolic function) is associated with an increased risk for sustained arrhythmia and sudden cardiac death in this group. The optimal indicator(s) of highest risk in these patients remains under investigation but will likely include electrophysiologic testing. Bifascicular block occurs commonly after repair of tetralogy of Fallot, but is usually benign. Isolated right ventricular infarction is rare. Most right ventricular arrhythmias associated with ischemia occur in the setting of iatrogenic catheter manipulation for pacing or hemodynamic monitoring. In conclusion, right ventricular arrhythmias involve an unusual and interesting group of clinical entities and appear to span the spectrum of arrhythmias mechanisms. A macroreentrant activation ring around the ventriculotomy scar may account for the arrhythmias following repair of tetralogy of Fallot. Microreentry at sites of morphologic abnormalities results in the arrhythmias associated with right ventricular dysplasia and ischemia. Triggered activity related to DADs or, less likely, abnormal automaticity, produce repetitive monomorphic ventricular tachycardia and nonischemic exercise-induced ventricular tachycardia, both of which usually originate from the right ventricular outflow tract. Iatrogenic ventricular tachycardia associated with catheter manipulation is especially likely to occur in the presence of right ventricular ischemia and infarction. It is important to recognize these clinical entities because treatment is specific.(ABSTRACT TRUNCATED AT 400 WORDS)

Bundle of His↗