Biomedical subjects

M Fromer

Publications and source records attributed to M Fromer.

At least 19 recordsLinked to original sources

PubMed1997

[Sudden death in hypertrophic obstructive and non-obstructive cardiomyopathy: can it be prevented?].

Sudden cardiac death constitutes the most devastating aspect of obstructive and non-obstructive hypertrophic cardiomyopathy. Loss of consciousness and family history of sudden cardiac death should alert the physician to the risk of sudden death. ECG, morphological and hemodynamic assessment, and exploration of central nervous activity are of little use in stratifying the risk of sudden cardiac death. Loss of consciousness associated with nonsustained ventricular tachycardia and inducible sustained ventricular arrhythmia identify patients at very high risk of sudden cardiac death. Nevertheless, many variable factors are involved in the pathophysiology of sudden cardiac death, and hence risk stratification of sudden cardiac death in patients with hypertrophic cardiomyopathy remains a very difficult clinical challenge.

Adolescent↗

PubMed1997

The acute effects of intravenously administered mibefradil, a new calcium antagonist, on the electrophysiologic characteristics of the human heart.

OBJECTIVE: This multicenter, double-blind, placebo-controlled, parallel-group study was designed to assess the acute effects of intravenous mibefradil on the electrophysiologic characteristics of the human heart. METHODS: Seventy-one patients referred for routine electrophysiologic testing were randomized to receive one of three intravenous treatments: placebo n = 23, 15 mg mibefradil in 15 min followed by 25 mg in 60 min (group 1, n = 24), or 35 mg mibefradil in 15 min followed by 45 mg in 60 min (group 2, n = 24). Electrophysiologic evaluations were performed prior to study drug administration and 30 min after the start of the infusion. Plasma samples were obtained at the start of the infusion and after 15, 75, and 105 min. RESULTS: Sinus node recovery time decreased significantly in Group 1 patients (-103 ms). Corrected sinus node recovery time in group 2 patients was 68.7 ms (P = 0.053). Compared to placebo, mibefradil produced mild but significant slowing of conduction in group 2 patients as manifested by an increase in the AH interval of 6.7 ms. Atrioventricular (AV) nodal refractoriness was increased, as indicated by a prolongation of the Wenckebach point in patients in both group 1 (32.1 ms) and group 2 (32.5 ms), compared to placebo. All adverse events were classified as mild to moderate and only one event (vasovagal attack) was considered to be treatment related. CONCLUSIONS: At plasma levels close to those found after chronic oral administration of 50 and 100 mg mibefradil, the higher dose produced an increase in corrected sinus node recovery time. Mibefradil also produced small but significant effects on AV nodal conduction and increased AV nodal refractoriness. Mibefradil had no effect on any other electrophysiologic parameter and was well tolerated.

Benzimidazoles↗

PubMed1997

Dual chamber pacing in hypertrophic obstructive cardiomyopathy: beneficial effect of atrioventricular junction ablation for optimal left ventricular capture and filling.

Clinical improvement with dual chamber pacing has largely been reported in patients suffering from hypertrophic obstructive cardiomyopathy and mainly attributed to the reduction of the subaortic pressure gradient. To be effective, pacing must induce a permanent and complete capture of the LV. In two patients of our collective, symptoms (angina and dyspnea NYHA Class III and/or syncopes) persisted or relapsed despite pacing. This was related to the inability to obtain full LV capture due to a too-short native PR interval. RF ablation of the AV junction was therefore performed in both patients, resulting in permanent AV block in one and prolonged PR interval up 310 ms in the second. Pacing was thereafter associated with an immediate and significant clinical improvement related to permanent LV capture, whatever the patient's activity. After RF ablation, the AV delay was set up to induce the best LV filling, as assessed by Doppler analysis of mitral flow. Our observations suggest that RF ablation or modification of the AV junction can be a successful procedure in some patients with residual or recurrent symptoms, when the latter result from a loss of capture or from the inability to program an AV delay that does not compromise the active component to LV filling. Doppler echocardiography is a simple and effective mean to assess the hemodynamic effect of AV interval modulation in this setting.

Angina Pectoris↗

PubMed1997

[Tachycardia-induced syncopes].

In 50% of the patients presenting with a syncope, the cause is cardiac. The incidence of sudden death with 24% is high in this group. Since most of the tachycardia-induced syncopes are due to ventricular tachycardia (VT), a careful diagnostic approach must be used. The possibility of a VT to end in a fibrillation is great, especially in the presence of a organic heart disease, which leads to a bad prognosis in such patients. The aim of a careful anamnesis and clinical history is to establish the presence of a cardiac disease. A Wolff-Parkinson-White syndrome, a long QT, an old myocardial infarction or a coronary artery disease (CAD) can be assessed by echocardiography (ECG). Stress testing is useful in evaluating a CAD and can possibly lead to a diagnosis when a VT or a supraventricular tachycardia (SVT) is induced. ECG is used to assess the cardiac ejection fraction and in the evaluation of a suspected right or left cardiomyopathy. The ambulatory ECG allow a diagnosis only in 2 to 3% of the cases. Nevertheless, the presence of more than 10 PVC/h and/or asymptomatic nonsustained VT is a predictor for sudden death in syncopy patients. Detection of late potentials has a sensitivity of 50 to 83% and a sensibility of 89 to 91% for the prediction of inducible sustained VT during electrophysiological studies (EPS) in patients with syncope. However, the usefulness of this technique is not fully established, since there is no significant difference in survival or recurrence of syncope between patients with and without late potentials. The EPS is an invasive technique and therefore used at the end of the investigations. The cardiovascular mortality is low (4%) in patients with a negative EPS. A treatment is mandatory in tachycardia-induced syncopes even when the cause is a SVT. Antiarrhythmic drugs are useful for the treatment of SVT. However, radiofrequency ablation of the accessory pathway is preferable, since the success rate is over 90%, and the side effects of chronic ingestion of antiarrhythmic drugs can therefore be avoided. Some VT can be treated successfully with drugs under the control of an EPS, but most of the patients must have the implantation of an internal cardiac defibrillator (ICD).

Death, Sudden, Cardiac↗

PubMed1996

[Specific percutaneous radiofrequency ablation of atrial flutter].

Radiofrequency catheter ablation has recently been successfully applied to patients suffering from atrial flutter. We report our experience in the ablation of typical atrial flutter in 17 consecutive patients refractory to drug treatment. The procedure was initially successful restoring sinus rhythm in 16 patients (94%). During a mean follow-up of 9 months atrial flutter recurred in 4 patients (23%). A second procedure was successfully performed in 2 patients; the other two patients are presently in sinus rhythm under amiodarone which was formerly ineffective. Finally, 59% of the patients were able to discontinue antiarrhythmic medication. In 4 out of 7 patients with dilated cardiomyopathy, the left ventricular ejection fraction normalized a few weeks after ablation. This successful technique should be considered early in the therapeutic approach to patients suffering from typical atrial flutter, to avoid numerous drug treatments, multiple hospitalizations and possible evolution toward non reversible dilated cardiomyopathy.

Adult↗

PubMed1996

[Therapeutic electrophysiology].

Due to tremendous technical progress during the last decade, electrophysiology offers now a therapeutic option to patients suffering from cardiac arrhythmias owing to radiofrequency catheter ablation. This article focuses particularly on the different radiofrequency ablation approaches used in the most common encountered supraventricular arrhythmias.

Atrial Flutter↗

PubMed1996

[Atrial fibrillation].

Atrial fibrillation is the most common arrhythmia the general practitioner as well as the physician in the hospital has to deal with. Even if it is said to be benign, heart failure and embolism may be deleterious consequences of this arrhythmia. In this article we well discuss the management of this arrhythmia, taking into consideration the etiologic factors, the pathophysiology of atrial fibrillation and therapeutic aspects from cardioversion to prevention of embolism.

Aged↗

PubMed1996

Impact of the implantable cardioverter-defibrillator on rehospitalizations.

UNLABELLED: Patients who survive out-of-hospital ventricular tachycardia or ventricular fibrillation are at risk of sudden cardiac death and often return to hospital after initial discharge. The frequency and duration of readmittance to hospital are not well known. Thus, the purpose of this study was to evaluate the impact of the implantable cardioverter defibrillator on frequency and duration of hospitalizations. METHODS: Between 1989 and 1993, 38 consecutive patients who had drug-refractory ventricular tachyarrhythmias were selected for the study. A total of 38 patients were implanted with the implantable cardioverter-defibrillator in accordance with the guidelines of the European Society of Cardiology. This analysis includes 35 of the 38 patients (92%). All hospitalizations which occurred one year before and one year after were studied. Clinical information for all patients was obtained by consulting medical records and by interviewing personal general practitioners. RESULTS: The annual number of hospitalizations before and after implantation of the implantable cardioverter-defibrillator was, respectively, 3.28 +/- 2.38 hospitalizations/ patient/year and 0.88 +/- 1.23 hospitalizations/patient/year (P < 0.05). Before implantation of the implantable cardioverter-defibrillator, patients were hospitalized a mean of 32.94 +/- 24.18 days/patient/year and after, 9.31 +/- 32.14 days/patient/year (P < 0.05). The number of hospitalizations for cardiac reasons decreased by 90%. Before implantation, the most frequent cause was ventricular tachyarrhythmia (47 hospitalizations for ventricular tachycardia and eight for ventricular fibrillation), while after implantation, it was as a result of the shock from the implantable cardioverter-defibrillator (11 hospitalizations). The number of hospitalizations for non-cardiac reasons were similar in the two time periods. Of the 35 patients, 26 (74%) had at least one appropriate successful ventricular tachycardia interrupted by the implantable cardioverter-defibrillator, while 17 patients (49%) had their ventricular fibrillation terminated. There is a significant difference in the rate of hospitalizations to intensive care units (ICU) between the two periods. Before implantation, 30% of hospital days were spent in the ICU, with 3% after. CONCLUSIONS: This study documents that the implantable cardioverter-defibrillator not only reduces the frequency and duration of hospital stays, but reduces admissions to the more expensive units in hospital. Taking into account the reduction in hospitalizations, the payback period for the implantation of an implantable cardioverter-defibrillator is 19 months.

Adolescent↗

PubMed1996

Bezold-Jarisch-like phenomenon induced by radiofrequency ablation of a left posteroseptal accessory pathway via the coronary sinus.

We report a case of asystole induced by radiofrequency (RF) ablation via the coronary sinus in a 35-year-old man suffering from symptomatic left posteroseptal accessory pathway. RF application provoked progressive slowing of the sinus rhythm, disappearance of the preexcitation, and an 8-second period of asystole followed by atrial fibrillation. The causal mechanism proposed is a strong stimulation of vagal afferent pathways linked with sensory endings of the inferoposterior myocardial wall leading to a Bezold-Jarisch-like phenomenon.

Adult↗

PubMed1996

[Intravenous withdrawal of infected cardiac pacemaker electrodes. Apropos of 5 cases].

Infection of a cardiac pacemaker and its electrodes is one of the most serious complications after implantation of a pacemaker, as it can be life-threatening and constitutes an absolute indication for complete withdrawal of the implanted material which, up until recently, could only be performed by thoracotomy or sternotomy with or without cardiopulmonary bypass. A new transvenous technique for complete removal of the infected pacemaker system has been recently described. We report 5 cases of infected pacemaker systems in which this technique was used successfully allowing withdrawal of 10 electrodes and thereby avoiding the need for a major surgical operation.

Aged↗

PubMed1995

[Permanent junctional reciprocating tachycardia: a little-known clinical entity curable with radiofrequency ablation].

We report our experience of 5 patients with the permanent form of junctional reciprocating tachycardia (PJRT), a rare form of supraventricular arrhythmia. PJRT was discovered at a mean age of 31 years (8-60 years) and the mean duration of tachycardia was 13 years (1-40 years). 4 patients had nearly incessant tachycardia and one had paroxysmal attacks. Heart rate varied between 100 and 190 beats/minute and the minimal heart rate was on average 114 beats/minute. Four patients had palpitations, 2 developed tachycardia-induced cardiomyopathy, reversible after control of the arrhythmia, and 4 had asymptomatic episodes of PJRT. ECG showed in all cases a narrow-complex tachycardia with inverted P waves in inferior leads and RP interval greater than PR. All patients presented a posteroseptal accessory pathway. 4 patients received different antiarrhythmic drugs with only partially effective results. Radiofrequency catheter ablation of the accessory pathway was performed in all patients and was successful in 4, who remained free of recurrence after a mean follow-up of 26.5 months (4-37 months). The procedure was partially successful in the 5th patient, who is now asymptomatic under sotalol. Radiofrequency catheter ablation is therefore the treatment of choice of PJRT, a rare arrhythmia which should nevertheless be known in order to treat the patient correctly and avoid progression to cardiac failure, which is not always completely reversible.

Adolescent↗

PubMed1994

[Endocavitary percutaneous ablation of tachyarrhythmias].

The indication and result of catheter ablation for supraventricular and ventricular arrhythmias are reviewed, with special emphasis on the need to inform the patient undergoing this type of procedure, the possible complications and our center's results.

Atrial Flutter↗

PubMed1994

[Mortality following sustained ventricular tachycardia treated according to the results of programmed ventricular stimulation].

The purpose of this study was to evaluate longterm mortality in 44 patients undergoing electrophysiologically guided therapy for sustained monomorphic ventricular tachycardia. We applied the following modified response criteria: non-inducibility or slowing of induced ventricular tachycardia to < or = 150 bpm. On this basis, 25/44 (57%) patients were classified as responders, and 19/44 (43%) as non-responders. Responders had palpitations significantly more often as the leading clinical sign (68% vs. 21%, p < 0.05). Non-responders showed a lower mean ejection fraction (36 +/- 15% vs. 46 +/- 17%, p < 0.05) and a trend to higher incidence of syncopal ventricular tachycardia (58% vs. 12%, p = 0.15). All responders and 3/19 non-responders continued on drug therapy. 11 non-responders received an implantable cardioverter-defibrillator (ICD), 3 underwent surgery and 2 catheter ablation. 14/44 patients (32%) died during a mean follow-up of 3.2 years. Sudden arrhythmic death occurred in 3/28 patients on drug therapy (1/25 responders, 2/3 non-responders), and in 2/16 non-responders with invasive therapy (one with an ICD and one after catheter ablation). The cumulative all-cause mortality at 3 years was similar in both groups (26% vs 22%, n.s.), but the mortality from sudden arrhythmic death showed a trend to be lower in the responder-group (0% vs 17%, p = 0.09).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1994

Relation between cycle length, volume, and pressure in type I atrial flutter.

Assuming that type I atrial flutter is a macroreentrant circuit, its cycle length should vary with the atrial dimensions. In order to test this hypothesis, flutter cycle length was measured while inducing atrial volume and pressure changes by postural and pharmacological means in seven patients undergoing a therapeutic programmed stimulation for type I atrial flutter conversion. Right atrial volume was estimated from B-mode echocardiography data. Basal values were compared with those obtained during inspiration, expiration, Valsalva maneuver, negative tilt (head down), and positive tilt (head up) with 0.8-1.6 mg p.o. nitroglycerin. The right atrial size increased slightly from 17.8 to 18.3 cm2 (P = 0.04) during the pressure load induced by negative tilt (+3 mmHg), with a corresponding lengthening of the flutter cycle length from 228 to 233 msec (P = 0.02). Similarly, pressure unloading of -2 mmHg by positive tilting and nitrates was accompanied by a decrease in right atrial size to 16.6 cm2 (P = 0.04), with a corresponding decrease in cycle length from 228 to 219 msec (P = 0.03). Respiratory maneuver yielded similar results with an inspiratory cycle lengthening, expiratory shortening, and further shortening during Valsalva maneuver. These experiments demonstrate a direct relation between cycle length and atrial volume in human type I atrial flutter. They underline the importance of the right heart preload and atrial size for the electrophysiological characteristics of type I atrial flutter. Beside its fundamental interest, this finding is important for the understanding of the mechanism of maintenance and therapeutic responses of this common arrhythmia.

Atrial Flutter↗

PubMed1994

Autonomic imbalance assessed by heart rate variability analysis in vasovagal syncope.

In this prospective study, the autonomic modulation of the sinus node of 12 patients (mean age 28 +/- 7 years) suffering from vasovagal syncope (VVS) was compared to that of 11 sex and age matched control patients (mean age 32 +/- 4 years) by analysis of heart rate variability. Spectral indices (low frequency power [Plf], high frequency power [Phf], total power [Pt], sympathovagal balance [LF/HF]) and temporal indices, the mean of all coupling intervals between normal beats (mRR), the standard deviation about the mean (sdRR), the percentage of adjacent R to R intervals differing by more than 50 msec (pNN50), and the root mean square of variations in successive R to R intervals (rMSSD) were compared at baseline and during head-up tilt between and within groups. Baseline results were similar in both groups. During tilt testing, comparison of results between groups revealed only significantly higher sdRR and rMSSD and lower LF/HF ratio in VVS patients. Within VVS patients, comparison of temporal and spectral analysis between baseline and tilt showed a significant increase of most indices (Plf, Phf, Pt, sdRR, and rMSSD) but a comparable LF/HF ratio; in contrast, control patients exhibited only a significant increase of LF/HF ratio. In conclusion, VVS patients who developed vasovagal syncope during head-up tilt demonstrated a nonreciprocal modulation of the sinus node by the autonomic nervous system indicative of a pronounced physiological sympathetic surge along with a paradoxical vagal input to the cardiovascular system.

Adult↗

PubMed1994

[Primary ventricular fibrillation and early recurrence: apropos of a case of association of right bundle branch block and persistent ST segment elevation].

The authors report the case of a 36 year old man who presented with an early recurrence of primary ventricular fibrillation. The initial investigations were normal apart from the finding of complete right bundle branch block with persistent ST segment elevation in the right precordial leads. The recurrence was observed 6 weeks after the initial diagnosis which led to the implantation of an automatic defibrillator. This clinical case is similar to a syndrome recently described of sudden death without obvious cardiac disease but with right bundle branch block and ST segment elevation.

Adult↗

PubMed1993

[Efficacy of adenosine triphosphate in terminating supraventricular tachycardia].

The efficacy of adenosine triphosphate (ATP) was tested in 23 patients suffering from supraventricular tachycardia; 10 patients had orthodromic circus movement tachycardia and 13 typical av nodal reentrant tachycardia. At a mean dose of 0.18 mg/kg all tachycardias were halted in less than 1 minute due to transient acute av nodal block followed by return to normal av conduction within 8 seconds. All patients had transient minor side effects. One elderly subject had a short episode of atrial fibrillation after the acute av block. In conclusion, ATP is useful and safe for rapid termination of supraventricular tachycardias incorporating the av node in their circuit.

Adenosine Triphosphate↗

PubMed1993

[Interventional arrhythmology].

Interventional arrhythmology deals with the nonpharmacological management of patients with symptomatic arrhythmias. Percutaneous catheter ablation is used to cure patients with arrhythmias due to accessory pathways or AV-node reentrant tachycardia. In patients with drug-refractory sustained, hemodynamically significant ventricular tachyarrhythmias, implantable third generation defibrillators provide an effective therapeutic modality. Our article provides a brief overview of these new therapeutic modalities and summarizes our local experience.

Arrhythmias, Cardiac↗