Search PubMed⌕ Search

Biomedical subjects

P Mabo

Publications and source records attributed to P Mabo.

At least 73 records · Page 4Linked to original sources
PubMed1993

Clinical role of d-sotalol and d,l-sotalol in supraventricular arrhythmias, including pre-excitation.

Numerous trials performed over the last 20 years, although uncontrolled, have shown the racemic d,l-sotalol is effective for the acute conversion and for long-term prevention of recurrences of supraventricular tachyarrhythmias. Sotalol appeared to be moderately effective in atrial fibrillation or atrial flutter, having somewhat greater efficacy in the case of atrioventricular (AV) nodal re-entrant tachycardia due to Wolff-Parkinson-White syndrome or concealed accessory pathway. These effects may stem from the combined class II and class III electrophysiologic properties of this drug. However, studies comparing d,l-sotalol to pure beta blockers in different 'models', especially postsurgical arrhythmias and Wolff-Parkinson-White syndrome, have suggested that the observed clinical benefit may be related to d,l-sotalol's class III properties. Thus, d-sotalol may be efficacious in these indications. Its precise efficacy should be defined in controlled clinical trials.

Adrenergic beta-Antagonists↗
PubMed1993

Functional dissociation of cellular activation as a mechanism of Mobitz type II atrioventricular block.

BACKGROUND: Several mechanisms have been advanced to explain Mobitz type II atrioventricular block in the ischemically damaged His-Purkinje system. Only recently, however, has an animal model been developed to study this form of conduction defect in vivo and in vitro. METHODS AND RESULTS: Conduction defects were induced in anesthetized dogs by ischemic damage to the proximal His-Purkinje system after anterior septal artery ligation. Stable 2:1 atrioventricular block, localized within the His bundle or in the proximal bundle branches, was obtained in each dog by atrial pacing at an average rate of 239 +/- 20 beats per minute (n = 12). In vitro studies were then performed from the same hearts. Action potentials and electrograms were simultaneously recorded from the His bundle and the proximal right bundle branch at the site of damage. At slow rates of pacing (40-60 beats per minute), the action potential amplitude was 85 +/- 4 mV, and some cells (10 +/- 3%) showed dissociation from the electrical activity in the bundle. At fast rates (149 +/- 11 beats per minute), during 1:1 conduction, the frequency of cellular dissociation increased to 57 +/- 6% (p < 0.001), and the action potential amplitude decreased (-31 +/- 4%, p < 0.001). The frequency of dissociation closely correlated with the reduction in action potential amplitude (r = 0.87, p < 0.001). These changes were markedly attenuated once 2:1 block developed. The site of block was not constant but rather showed a dynamic behavior with spatial shifting in response to changes in pacing rate or the introduction of extrastimuli. CONCLUSIONS: These results indicate that in the ischemically damaged proximal His-Purkinje system, an increase in rate leads to reduced and asynchronous cellular activation before 2:1 block. The latter provides a more stable activation pattern, because the frequency of dissociation is markedly reduced.

Action Potentials↗
PubMed1993

The comparative antiarrhythmic and proarrhythmic activity of a 3,7-diheterobicyclo[3.3.1]nonane, BRB-I-28, and lidocaine in the 1-4-day-old infarcted dog heart.

We compared the electrophysiological effects and quantified the antiarrhythmic/proarrhythmic potential of the 3,7-diheterobicyclo[3.3.1]nonane-derivative, BRB-I-28 and lidocaine in 15 consecutive postinfarction dogs. Electrophysiologic studies were performed in anesthetized animals, 1-4 days (mean +/- SE = 2.47 +/- 0.36) after the two-stage ligation of the left anterior descending coronary artery. Inducibility of sustained monomorphic ventricular tachycardia (SMVT) was compared in the pre-drug state, and after i.v. lidocaine (3 and 6 mg/kg) and BRB-I-28 (3 and 6 mg/kg) administration. During the control state, SMVT was inducible in 6/15 dogs (40%). After the administration of lidocaine, the rate of the inducible SMVT slowed (353 +/- 91 to 272 +/- 96 beat/min; p < 0.01), but due to the proarrhythmic action of the drug, SMVT became inducible in 13/15 dogs (87%). Sustained reentry was induced after 3 mg/kg lidocaine in 3 dogs and after 6 mg/kg in 4. The mean aortic blood pressure in these SMVTs was 36 +/- 8 mm Hg. After administration of BRB-I-28 (6 mg/kg) SMVT was not inducible in 2/6 and in 4 the SMVT rate was slowed (380 +/- 104 to 208 +/- 105 beat/min; p < 0.005) before termination in 3. In 2 dogs SMVT was induced after BRB-I-28 was given whereas they were non-inducible in the control state (proarrhythmic effect: 13%). Furthermore the hemodynamic state during the SMVTs was more stable after BRB-I-28 (mean aortic blood pressure = 65 +/- 7 mm Hg; post-BRB-I-28 vs post-lidocaine, p < 0.001). During sinus rhythm, lidocaine caused a transient lowering of the MBP (105 +/- 17 to 84 +/- 18 mm Hg; p < 0.001), whereas, BRB-I-28, induced a consistent but short-lasting pressor response (98 +/- 18 to 120 +/- 29 mm Hg; p < 0.001) after its bolus injection. The low proarrhythmic activity and the lack of a cardiodepressant action makes this new chemical class of antiarrhythmics worthy of further development.

Animals↗
PubMed1993

[Radiofrequency catheter ablation of accessory atrioventricular pathways: initial experience in 33 patients].

The authors report their experience in endocavitary radio-frequency ablation of 37 secondary pathways carried out in 33 consecutive patients. The indications for radical treatment were based solely on clinical arguments in 15 patients, on a combination of disabling signs and threatening electrophysiological signs in 17 patients and on high retrograde permeability in 1 asymptomatic patient. Endocavitary exploration revealed 26 left lateral sites, 7 posterior paraseptal sites and 4 right lateral sites. The procedure was successful in 88% of cases. Electrophysiological follow-up, carried out routinely in all the patients 2 months after the procedure, revealed a single recurrence (3%) which was treated by radio-frequency again, this time with a successful outcome. There was only one complication, a complete AVBBB following ablation of a left posterior paraseptal Kent's bundle, which required a permanent pacemaker. These results were similar to those reported in the literature and clearly demonstrate the efficacy of radio-frequency treatment of the secondary pathways, with a moderate risk of complication. These results were similar to those reported in the literature and clearly demonstrate the efficacy of radio-frequency treatment of the secondary pathways, with a moderate risk of complication. Recent advances in the field of endocavitary ablation have made it possible to change the method of handling symptomatic Wolff-Parkinson White syndromes, by enlarging the indications for radical treatment in order to enhance the comfort and quality of life of the patient.

Adolescent↗
PubMed1992

Evaluation of bepridil efficacy by electrophysiologic testing in patients with recurrent ventricular tachycardia: comparison of two regimens.

The purpose of the study was to evaluate this effect of different doses of intravenous and oral bepridil on the induction of ventricular tachycardia. Thirty-eight patients underwent electrophysiologic evaluation for recurrent ventricular tachycardia (VT). Sustained monomorphic VT was induced by programmed ventricular stimulation, using up to three extrastimuli in all patients. The effects of intravenous bepridil (2 mg/kg) were evaluated during the initial study. Intravenous bepridil prevented the induction of sustained VT in eight patients (21%). Electrophysiologic study was repeated after oral bepridil. In six patients the study was stopped because of adverse effects or VT recurrence. Thirty-two patients underwent repeat study 7 days later, taking oral bepridil, 500 mg/day (n = 16) or 900/day (n = 16). A dose of 500 mg/day of bepridil prevented the induction of sustained VT in only one patient. A dose of 900 mg/day of bepridil prevented the induction of sustained VT in eight patients. There were no significant clinical adverse effects, except in one patient receiving intravenous bepridil. The response to intravenous bepridil did not predict the response to oral bepridil. The response to intravenous or oral bepridil was not related to the plasma level of bepridil but was related to a higher left ventricular ejection fraction. Eight patients (21%) in whom VTs were noninducible on oral bepridil were discharged on 300 mg/day of bepridil if their initial loading dose was 500 mg/day or on 600 mg/day if their initial loading dose was 900 mg/day. They remained free of VT during a follow-up of at least 6 months.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Oral↗
PubMed1992

Conversion of Mobitz type II AV block to 1:1 AV conduction by premature ventricular beats.

Preliminary experiments in a canine model of Mobitz type II atrioventricular (AV) block showed improvement of conduction after premature ventricular beats. In this investigation, the authors studied the mechanism(s) responsible for this response. In vivo studies were performed in 16 anesthetized dogs. Block was induced by ischemia after septal artery occlusion or by mechanical trauma. Two pairs of plunge electrodes were inserted in the proximal and distal His bundle. An electrode catheter was positioned at the level of the aortic root to provide an overall view of His bundle activation. Bipolar pacing was performed from the high right atrium, right ventricular outflow tract, and proximal and distal His bundle. Infra-nodal 2:1 AV block was consistently induced at an atrial rate of 238 +/- 21 beats/min. In 15 dogs a narrow time window (10-60 ms; mean, 32 +/- 6 ms) was found during which premature beats resulted in transient (2-11 beats; n = 9) or persistent (n = 8) restoration of 1:1 AV conduction. Retrograde penetration of the site of block, that is, Hb, was found even when the anterograde impulse was blocked, demonstrating the asymmetric nature of anterograde versus retrograde conduction. In vitro studies were performed in the same hearts. Intracellular recordings were obtained in the damaged His bundle and proximal right bundle. The site of block showed frequent displacements along the bundle. The introduction of a retrograde stimulus during 2:1 block restored 1:1 anterograde conduction.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

Failure of epinephrine to induce severe cardiac arrhythmia in rats with ventricular hypertrophy secondary to aortic pressure overload.

The arrhythmogenic action of epinephrine was studied in 3 groups of rats: 10 rats with mild constriction of the abdominal aorta (group H1), 10 rats with severe constriction (group H2), 10 sham-operated age-matched rats (group C). Blood pressure and ECG were recorded before, during and after 5 min. perfusion of increasing doses of epinephrine (1, 5, 10 and 25 micrograms.kg-1.min.-1). Ventricular arrhythmia was evaluated from the ECG using a modified Lown's grading system. The ventricular hypertrophy index was calculated from the heart/body weight ratio (mg/g). The mean arterial blood pressure was significantly higher in groups H1 and H2 than in the control group. The ventricular hypertrophy was significant in group H2, but not in group H1. There was no significant difference between the amplitudes of the epinephrine-induced hypertensive responses in the 3 groups but the extent of arrhythmia was significantly lower in the animals with high hypertrophy index.

Animals↗
PubMed1992

[Efficacy and tolerance of 2 new percutaneous vena cava filters. A prospective study in 80 patients].

Eighty consecutive patients with an average age of 66.5 +/- 16 years were reviewed 3 and 9 months after implantation of two new percutaneous vena caval filters (Filcard, Cardial) in order to evaluate their efficacy and tolerance. The indications were: a contra-indication to anticoagulants in 19 cases, recurrent pulmonary embolism under anticoagulant therapy in 22 patients, chronic cor pulmonale in 4 patients; finally, in 35 cases, the filter was implanted prophylactically for a "floating" or extensive ilio-caval thrombosis under anticoagulant therapy or in high risk patients: severe cardio-pulmonary failure, malignant disease, massive pulmonary embolism with a contra-indication to fibrinolytic therapy. All implantations were performed by the jugular approach with no local or general complications apart from one pericaval haematoma with a favourable outcome. Cavography and opacification of the renal veins was carried out systematically during implantation. All patients underwent clinical examination, antero-posterior and lateral X rays of the filter, pulmonary scintigraphy, antero-posterior and lateral cavography, a CT scan of the filter, Doppler ultrasonography and rheoplethysmography of the legs 3 months after implantation. At 9 months, clinical examination, abdominal X rays and rheoplethysmography were repeated. There was 100% follow-up at 3 and 9 months. The complications observed at 3 and 9 months were: 5 cases of malposition (6%), 3 recurrent pulmonary emboli (4%), 9 recurrent venous thromboses (13%), 4 vena caval thromboses (5.7%), 7 thrombi caught in the filter (10%), 27 perforations of the vena cava (38%), 3 over 30 degrees tilts of the filter (4%) and 22 migrations (31%).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

[Influence of exercise on the permeability of accessory pathways and supraventricular arrhythmia in Wolff-Parkinson-White syndrome].

The influence of adrenergic stimulation on the effective anterograde refractory period of the accessory pathways and on supraventricular arrhythmias, was studied in 20 patients (average age 38 +/- 16 years) with an untreated permanent Wolff-Parkinson-White syndrome and a resting anterograde refractory period < or = 400ms. Repeated electrophysiological studies with a single endocavity catheter positioned near the atrial pole of the accessory pathway were performed under basal conditions and during a standardised exercise test on a bicycle ergometer. The effective anterograde refractory period of the accessory pathway, the length of the tachycardia cycle during reciprocating orthodromic tachycardia, the average heart rate, the percentage of preexcited QRS complexes during induced atrial fibrillation, were measured in all patients under basal conditions and at the peak of exercise. Exercise significantly reduced the anterograde refractory period of the accessory pathway (287 +/- 49 ms at rest versus 238 +/- 24 ms on exercise: p < 0.001), the cycle of orthodromic tachycardia (302 +/- 32 vs 260 +/- 22 ms p < 0.001), the minimal R-R interval (270 +/- 65 vs 227 +/- 46 ms: p < 0.05) and % of preexcited QRS complexes (75 +/- 33 vs 51 +/- 39: p < 0.05) in atrial fibrillation whilst increasing the average heart rate (165 +/- 42 vs 202 +/- 39 bpm: p < 0.02). Adrenergic stimulation significantly improves anterograde conduction in the accessory pathway. The reduction in the % of preexcited QRS complexes in atrial fibrillation could indicate a preferential action of catecholamines on the nodo-hisian pathway.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1992

[Results of coronary-angiographic evaluation after endocavitary fulguration of the accessory pathways].

Left ventricular aid coronary angiography was performed systematically in 32 consecutive patients (average age 34 +/- 16 years) to assess the potential risk of coronary and myocardial lesions after high energy catheter ablation of an accessory pathway. The control was performed 2 to 6 months after the procedure in 30 patients and as an emergency immediately after the procedure in 2 patients because of prolonged ST segment elevation in 1 and an echocardiographic abnormality in the other. The catheter ablation was performed by a right heart approach in 19 patients and by retrograde catheterisation of the left heart in the other 13. The average number of shocks delivered was 3.6 +/- 2.4 in 1.8 +/- 1.2 session with an average energy of 632 +/- 220 joules. The global success rate was 88%, 70% complete successes and 18% clinical successes. The left ventricular and coronary angiographies were normal in 31 patients, including the 2 patients investigated as an emergency. On the other hand, one totally asymptomatic patient in whom a left lateral bundle of Kent had been ablated 2 months previously by a retrograde transaortic approach, had a large pseudo-aneurysm of the left ventricular posterior wall and coronary angiography showed a fistula between the first lateral branch of the circumflex artery and the left ventricle. At surgery, a localised rupture of the mitral annulus was confirmed. Two factors may at least partially explain this complication: the quantity of energy delivered (1,000 joules) in a single session to a limited area, and the site of ablation on the ventricular side of the mitral annulus.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1992

[Arrhythmogenic cardiomyopathies of the right ventricle].

Arrhythmogenic cardiomyopathies of the right ventricle (ACRV) are defined by an association of left delayed type ventricular arrhythmias, ranging from apparently uncomplicated extrasystoles to more severe or even potentially lethal arrhythmias such as polymorphous VT and ventricular fibrillation, with an anatomical substrate consisting of adipose or fibro-adipose degeneration of the myocytes of the free wall of the ventricle, which may be either focal (in particular: apex, anterior surface of the infundibulum and the sub-tricuspid region), or more diffuse. It is then accompanied by RV systolic dysfunction with dilatation of the cavity. This apparently well defined clinico-pathological entity is in fact more complex, if only because of the existence of associated lesions of the left ventricle in 1/3 of cases. The distinction from Uhl disease remains blurred, in particular in diffuse forms. It is most probable that more than one etiology is involved. A dysgenetic mechanism with probable autosomal dominant transmission has apparently been shown in familiar forms which are associated with a particularly severe risk of progression. The hypothesis of sequelae of multifocal myocarditis appears to be the most probable in sporadic forms. In the absence of histological criteria, which it is difficult to demand in view of the variability of results and potential dangers of endomyocardial biopsy involving such thin and fragile ventricular walls, the diagnosis of ACRV is based upon the concomitant existence of: (1) electrophysiological criteria: ventricular arrhythmias, in particular sustained monomorphous VT, with the particular feature of a very high degree of sensitivity to adrenergic stimulation (exercise), the existence of late potentials on the high amplification ECG, a highly specific sign, though unfortunately of poor sensitivity in localized froms, those which are most difficult to identify (2); segmentary morphological and kinetic RV abnormalities, most often resulting in localized akinetic or dyskinetic parietal vaulting, with stasis "in situ". Modern imaging methods (echocardiography, angioscintigraphy with phase analysis, nuclear magnetic resonance imaging, etc.) unfortunately do not yet offer an alternative to selective cineangiography of the RV which is the reference investigation when it is performed and interpreted under strict conditions. Several reports of sudden death or of ventricular fibrillation seen in confirmed cases of ACRV, as well as the publication of a number of autopsy registers indicating that this condition is one of the primary causes of sudden death in young individuals and in athletes, have cast doubt on the benign prognosis initially attributed to this condition.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed1992

[Radiofrequency ablation of atrioventricular conduction during the 5th month of pregnancy].

The authors report the case of radiofrequency ablation of atrioventricular conduction in a 5 months pregnant woman who had hypertrophic cardiomyopathy. The indication of this procedure was a poorly tolerated resistant supraventricular tachycardia with foetal distress. A dual-chamber rate-assisted pacemaker programmed in the VVIR mode was implanted during the same procedure normally, with normal delivery of a healthy child at 8 months' gestation.

Adult↗
PubMed1992

[Long-term outcome of a hospital series of patients with atrio-ventricular accessory pathway].

Ninety five patients with a mean age of 39 +/- 19 years, 82 of whom were symptomatic, having an accessory atrioventricular bidirectional conduction pathway (WPW syndrome: 77; "concealed": 18) were followed up for an average of 7.3 +/- 2.6 years. The objectives were to analyse: the incidence and causes of death and the possible predictive factors of death due to the WPW syndrome--the influence of medical treatment and type of medication on survival and symptoms. Of the 8 cardiac deaths, 6 seemed to be related to the WPW syndrome, a prevalence of 7.8% and an annual incidence of 1.1/1000. The main risk factors which were identified were: age 62 +/- 8 years versus 37 +/- 15 years in survivors; p < 0.02--associated organic heart disease, especially ischaemic heart disease (5/6)--the description of severe symptoms, in particular recurrent syncope--documented malignant spontaneous or induced arrhythmias (5/6)--anterograde AV conduction with an effective refractory period < or = 230 msec in 4, though it was only 270 msec in the other 2 patients, indicating that this parameter is not specific--amiodarone (6/6) did not prevent the fatal outcome in this particular group of patients. In the "benign" forms, only betablocker drugs could significantly reduce the frequency and severity of symptoms, especially when compared with Class I or IC antiarrhythmics. These results suggest that the indications of radical treatment should be widened in high risk patients, especially when elderly and with associated coronary artery disease. They also suggest that the role of betablocker drugs should be reevaluated in the so-called "benign" symptomatic forms.

Adolescent↗
PubMed1992

[Doppler echocardiography and double chamber pacing].

Doppler-echocardiography is playing an increasing role in cardiac pacing: 1) Before implantation, to determine any cardiac disease possibly accompanying the conduction disturbance, and the quality of atrial function in order to identify the appropriate indications for the type of pacing which will restore normal AV synchronism. Alongside morphometric data (size of atria, etc.), this analysis is based above all on the evaluation of LV filling flows and ejection, if necessary during provisional pacing in DRV mode. It is important to be aware of and prevent certain problems: 1st degree AV block with very long PR, high degree interatrial conduction disturbances, etc. 2) To evaluate the possible benefits of pacing in certain new indications, e.g. obstructive hypertrophic cardiomyopathy (measurement of intra-LV gradient in sinus rhythm and with DRV pacing with total ventricular capture). 3) After implantation, to optimise the programming of double-chamber pacemakers and in particular AV intervals (base-line AV interval with paced atrial cycle, AV interval with detected atrial cycle, hysteresis of AV interval corresponding to the difference between the two previous values, slope of automatic variation in AV interval during exercise, etc.). Individual programming of these parameters based upon analysis of transmitral and ejection flow rates, at rest and, if necessary, during exercise, enables the optimisation of cardiac function (which is above all useful in the presence of concomitant organic heart disease) while at the same time improving the electrophysiological behaviour of the pacemaker at high frequencies.

Cardiac Pacing, Artificial↗
PubMed1992

[Value of an algorithm of automatic adaptation of the atrio-ventricular delay to the instantaneous atrial rate in cardiac stimulation].

It has been suggested that an algorithm of automatic adaptation of the AV delay to the instantaneous atrial rate be introduced into the program of DDD pacemakers to reproduce the physiological adaptation of the PR interval to effort, characterised by progressive shortening inversely linearly related to the heart rate. In order to evaluate the potential benefits in conditions of "standard" programming (basal AV delay the same for all patients: maximal frequency of 1/1 AV synchronisation uniformly limited to 120 bpm), a haemodynamic study was undertaken in 10 patients who had permanent DDD pacemakers implanted for advanced AV block. Measurements were taken during two standardized exercise stress tests (20 W/2 mn steps from an initial load of 20 W) performed in a random order, one with a fixed AV delay of 156 ms and the other with an "automatic AV delay" allowing linear reduction from a maximum value of 156 ms at rest to a minimum value of 84 ms at the maximum heart rate of 120 bpm. At the peak of exercise the "automatic AV delay" significantly affected 4 parameters: the paced ventricular rate (p = 0.008) and rate-pressure product (p = 0.005) which increased, pulmonary capillary pressure (p = 0.03) and cycle-to-cycle variability of systolic and diastolic blood pressures (p = 0.02 < p < 0.0001) which decreased. There was a tendency (NS) to slowing of the spontaneous atrial rate and to increase in cardiac output. This increase was significant in some patients and seemed to be due to a good relationship between the individual optimal value of the value basal AV delay measured by Doppler echocardiography and the value programmed in this study (156 ms).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1992

[Isolated myocardial infarction in the right ventricle: clinical and echocardiographic study].

The purpose of this study was, on the basis of 4 cases of isolated infarction of the right ventricle (RV), to describe the clinical profile of this disorder and compare the value of ultrasonography with other invasive methods of investigation (hemodynamic and kinetic angiocardiographic methods) in diagnosis and evaluation of the prognosis. In all cases the clinical situation was indicative: prolonged chest pain, slight enzymatic peak, downward shift of the ST segment in V3R and V4R. The diagnosis was rapidly confirmed by ultrasound in the face of the abnormal isolated segmental kinetics in the RV, associated with cavity dilatation and tricuspid incompetence. These data were consistent with those of RV kinetic angiography. Right cardiac catheterism showed the classical signs of adiastolism with no reduction in heart rate, except in one case. The outcome was generally simple. Ultrasound revealed the regression of the abnormalities of parietal kinetics. Thus, ultrasound examination is shown to be a method of exploration which is easy to perform and effective in the diagnosis of this disorder with a good prognosis.

Aged↗
PubMed1991

[New cardiac pacemakers].

Because of the extraordinary technological progress made over the past years in pulse generators, the objective and indications of definitive cardiac pacing have greatly changed. All the different advantages are aimed at mimicking the electrophysiological and mechanical conditions of normal heart function. We have seen the development of: DDD mode dual chamber pacemakers, which in cases of AV block recreate normal AV synchrony; single chamber rate-responsive units piloted by an external captor responding to the organism's metabolic needs (intra-corporal vibrations resulting from exercise, respiratory rate, minute ventilation, QT interval, central temperature, SV O2...); they provide effective correction of atrial (AAI-R mode) or ventricular (VVI-R mode) chronotopic incompetencies often associated with chronic conduction disorders which make it impossible for patients paced in VVI or AAI mode to adapt heart rate to exercise level; and finally, "universal" pacemakers capable of pacing in all the single or dual chamber modes with rate responsiveness to one or several captors. These new pacemakers offer adaptability to the paced patient's needs as they vary throughout his lifetime. These units will probably be the "standard" cardiac pacemakers of the future.

Arrhythmias, Cardiac↗