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C Brechenmacher

Publications and source records attributed to C Brechenmacher.

At least 37 records · Page 2Linked to original sources
PubMed1992

[Predictive factors of regularization and maintenance of sinus rhythm in chronic atrial fibrillation].

The aim in treating chronic atrial fibrillation, is not limited to simply achieving immediate regularization. What matters, is sustaining the sinus rhythm. The various methods of regularization, using either medical procedures or cardioversion, involve constraints and risks. Investigation of the relapse predicting factor is of great value in evaluating the benefit/risk ratio. For regularization, the absence ultrasound signs of heart disease, an undilated left atrium, recent atrial fibrillation and all forms of heart disease which are curable, albeit surgically, are indicative of success. With regard to prophylaxis, relapses occur more frequently in cases involving mitral valve disease, long-standing atrial fibrillation or a dilated left atrium.

Age Factors↗
PubMed1992

[Embolic complications of chronic atrial fibrillation].

Systemic embolism secondary to chronic atrial fibrillation usually affect the cerebral circulation. The risk of a cerebrovascular accident in patients with chronic atrial fibrillation, irrespective of the aetiology, is 1.8 to 7.5 times that of the general population. The embolic risk is 18 times greater in patients with atrial fibrillation related to the rheumatic heart disease. The risk of patients under 60 years of age with idiopathic atrial fibrillation does not seem to be different to that of the general population. The risk of early recurrence of embolism in the first 30 days ranges from 8 to 15%. The risk of late recurrence varies but seems to be higher than that of the general population. The prognosis of embolic cerebrovascular accidents is poor with a 20% mortality rate. The benefits of preventive therapy of embolism with oral anticoagulants have been clearly established in rheumatic atrial fibrillation and in other indications. In non-valvular atrial fibrillation the benefits have to be compared with the risks of treatment. The incidence of hemorrhage due to anticoagulant therapy is between 3 and 5% per year per patient (about 1% of severe haemorrhage). Three randomised studies of primary prevention have shown a significant reduction of the embolic risk in non-valvular atrial fibrillation treated by warfarin compared to patients on placebo. Only one study has shown a significant reduction of the embolic risk in patients under 75 years of age with non-valvular atrial fibrillation treated with 325 mg/day of aspirin. However, anticoagulant therapy does not seem necessary in carefully selected patients under 60 years of age with idiopathic atrial fibrillation (less than 5% of all patients).

Aspirin↗
PubMed1991

[Contribution of imaging to the study of aortic aneurysms].

All aortic aneurysms require a positive diagnosis, a differential diagnosis and an assessment of extension. Several exploratory methods can be contemplated. In patients with warning symptoms, conventional radiology may point to the diagnosis. The reference method remains retrograde aortography which may be either conventional and seriographic or, better, radiocinematic with orthogonal projections and, if possible, digital. The site and morphology of the aneurysm, and in particular its inner channel are thus demonstrated. Computerized tomography is less invasive and usually of great value, notably for the horizontal, thoracic and abdominal aorta, not only to confirm the diagnosis but also to determine the size of the inner channel, parietal thrombi and aortic walls, as well as relations with nearby structures. Other, totally non-invasive methods are widely utilized to explore aortic aneurysms. These are ultrasonography and its variants (notably Doppler-echocardiography and the transoesophageal route), and magnetic resonance imaging which provides three-dimensional and anatomical views of the vessel. These last two examinations alone usually confirm and outline the aortic aneurysms. They must therefore be utilized as first-line examination, arteriography it is various forms being reserved for emergencies or special cases.

Aorta, Abdominal↗
PubMed1991

[Arrhythmias in chronic heart failure. Prognostic significance and treatment].

Almost 50 percent of patients with chronic heart failure die of sudden death often due to arrhythmia. In these patients the prognosis is related to the severity of myocardial lesions and also, probably, to the presence of ventricular arrhythmias. The potential severity of which can be assessed by various methods, including ECG, Holter monitoring, late potentials study and programmed ventricular stimulation tests. The first therapeutic measure to improve the prognosis of heart failure is to improve the myocardial function by prescribing converting enzyme inhibitors. The second measure consists of acting on potentially dangerous ventricular arrhythmias with few or no symptoms. Among antiarrhythmic agents, only beta-blockers and amiodarone seem to be valuable.

Adrenergic beta-Antagonists↗
PubMed1991

Complete atrioventricular block following mediastinal irradiation: a report of six cases.

Complete atrioventricular block (AVB) following radiotherapy has been reported rarely, usually after high dose mediastinal irradiation for Hodgkin's disease or lung or breast carcinoma. We report six new cases of episodic complete infranodal AVB, requiring permanent pacemaker implantation. The mean age was 48-years old (ranging from 25-60) at the first Adams Stokes attack, mean delay was 12 years after irradiation (10-18), and mean radiation dose was 5,200 rads (4,000-6,500). All patients had abnormal interval electrocardiograms (right bundle branch block in two, left bundle branch block in three, alternating left and right bundle branch block in one). Electrocardiograms during the episode of AVB or Holter recordings were consistent with infranodal block in all patients; electrophysiological study performed in five patients confirmed infranodal AVB in four, and one was normal. Pericardial disease was constant, which included pericardial constriction in four patients. Two patients died after failure of pericardiectomy to improve congestive heart failure, due to epicardial, myocardial, and endocardial involvement. Noncardiac mediastinal lesions were present in four cases. Since this delayed complication may occur in patients of such age that the relation between the AVB and the chest irradiation is questionable, we propose the following etiologic criteria; high radiation dose (over 4,000 rads); delay of 10 years or more; abnormal interval tracings; pericardial involvement; and associated cardiac or mediastinal radiation-induced lesions.

Adult↗
PubMed1991

[Sensory neuropathy and subacute dysautonomia. Clinical and pathological study].

We report a case of severe subacute autonomic and sensory neuropathy in a 52 year-old man. Cerebrospinal fluid protein was 275 mg/dl. Electrophysiological data were consistent with an axonal sensory neuropathy. Nerve biopsy showed a severe decrease in myelinated fibers, and a less severe loss of unmyelinated fibers. No cause was found and recovery was almost complete over 4 years, with minimal persistent dysautonomia. This case and 4 similar reported cases are compared with pure dysautonomia and with sensorimotor dysautonomic neuropathy. The site of damage is discussed and it is suggested that these cases are axonal forms of inflammatory polyneuropathy.

Autonomic Nervous System Diseases↗
PubMed1991

[Fulguration of atrial flutter in man. A pathological case].

A 63 year old man with ischemic heart disease underwent two sessions of catheter ablation in the inferior right atrium for poorly tolerated resistant and recurrent atrial flutter. After endocavitary mapping and comparison with surface recordings of the f waves, a shock of 50 joules was delivered to the zone situated anteriorly to the inferior vena cava, under the orifice of the coronary sinus and behind the tricuspid valve. Early recurrence of the arrhythmia led to a second attempt and another 50 joules shock was administered to the same area. Another short term recurrence led to definitive nodohisian interruption with a 270 joules shock. Thirty months later, the patient died suddenly during an episode of cardiac failure. Macroscopic examination of the right atrium showed a zone of parietal congestion measuring 4 x 3 cm with a very thin, translucid, central zone measuring 3 x 1.5 cm, just anterior to the inferior vena cava in the right atrial free wall. Histological examination of this zone showed an intense, mutilating fibrosis dissociating the muscular fibres, of the pectinate muscle and even replacing the myocardium in certain regions. In the Eustachian valve, there were muscular fibres, probably representing the posterior internodal pathway, which were also fibrosed. These observations suggest that: 1) in view of the extreme thinness of the atrial wall at the site of ablation there is a high risk of perforation even when right endoatrial catheter ablation is performed with low energy shocks; 2) the posterior internodal pathway does not seem to be an essential component for atrial flutter.

Atrial Flutter↗
PubMed1991

[Internal electroshock in the treatment of chronic atrial fibrillation resistant to external cardioversion. Initial results apropos of 21 patients].

The authors report their experience involving 21 right endoatrial electroversions aimed at converting chronic atrial fibrillation resistant to external electroversion. All prior precautions were taken to ensure that the shocks were not in contact with an atrial wall nor over the node-His bundle (two dimensional radiological identification, endocavitary recordings). A total of 37 internal electric shocks were administered. Results were: 16 immediate successes out of 21 (72.2 per cent) and 12 short term successes out of 21 (57 per cent). The mean effective energy value was 200 Joules. There were no traumatic complications. The authors conclude that this technique is effective and reliable in the management of atrial fibrillation resistant to external electroversion.

Adult↗
PubMed1991

[Role of internal cardioversion in the treatment of permanent atrial fibrillation. Early results apropos of 28 cases].

Internal cardioversion is a new method of treating atrial fibrillation. It consists in delivering an electric shock between an electrode positioned in the right atrium and a dorsal electrode. A quadripolar electrophysiological catheter is used as the proximal electrode, the two distal poles of which are used to locate the His bundle deflection. Care is taken that the electrode used for cardioversion is not in contact with the atrial wall by using biplane fluoroscopy and unipolar endocavitary recordings. Twenty-eight patients (18 men and 10 women) average age 55 years, underwent this treatment for chronic atrial fibrillation resistant to one or two attempts at external cardioversion. Each patient was given one or two shocks (average 1.68) in the same session. There were 22 immediate reversions to sinus rhythm, giving a primary success rate of 78.57%. Four patients relapsed in the 3 days following the procedure, giving a short term success rate of 64.28%. The minimum effective energy would seem to be 200 joules. The only rhythm complications were sinus bradycardia and/or atrioventricular block lasting a few seconds, both countered by prophylactic ventricular pacing : no traumatic complications due to electric shock were observed. The long term results show sinus rhythm maintained in 66.66% of patients at 6 months and more. In conclusion, internal cardioversion is an effective method of treating cardiac arrhythmias resistant to external cardioversion. The procedure would seem to be reliable and relatively atraumatic. The long term results are promising, particularly the stability of sinus rhythm which seems to be longer than after external cardioversion, by they need further confirmation.

Adult↗
PubMed1990

Chronic inflammatory demyelinating polyneuropathy in childhood: ultrastructural features of peripheral nerve biopsies in four cases.

Peripheral nerve biopsies (PNB) from four children suffering from subacute or chronic inflammatory demyelinating polyneuropathy were studied by electron microscopy. Remyelinating features with onion bulb formations, inflammatory cell infiltrates and active demyelinating lesions were strongly suggestive of the disease. In the first case, a second PNB, performed after 7 months of severe subacute course, showed a striking evolution of the lesions. In the second case and in spite of severe neurological symptoms, the PNB was almost normal, suggesting that inflammatory lesions were mainly located in the proximal parts of the nerve. No signs of active demyelination could be seen in the third case but onion bulb formations and inflammatory cell infiltrates were present. In the fourth case, characteristic lesions of active demyelination were associated with a history of familial polyneuropathy; this association suggests an auto-immune process in certain kindreds with hereditary motor and sensory neuropathy.

Adolescent↗
PubMed1990

[In vitro study of the effects of high frequency electrical current on cardiac pacemakers].

The authors studied the possible consequences of the use of high frequency electrical currents of cardiac pacemaker function. Twenty-five unipolar pacemakers (22 single and 3 double chamber) were tested. They were connected to a pacing catheter, emerged in a saline bath and submitted to a modulated and then unmodulated current of 348 KHz in as many pacing modes as possible for each unit. Three dangerous deprogrammations were observed which could nevertheless be easily corrected. Five pacemakers immediately adopted the reversion mode specified by their manufacturer. The other changes observed only lasted as long as the electric current was applied. The commonest abnormality was a drop in the output voltage proportional to the energy delivered which sometimes led to true inhibition of the pacemaker. Two abnormal rate increases were observed reaching frequencies higher than 250/mn. No particular pacing mode seemed to protect the pacemakers from the effects of high frequency currents.

Cardiac Pacing, Artificial↗
PubMed1990

[Dysautonomia. A clinical study of a case, ultrastructural data].

We report a new case of non-familial dysautonomia. The patient was a boy with no known Jewish ancestry in whom psychomotor retardation in early infancy failed to lead to specialized evaluation. Regressive episodes of ataxia developed at the age of three and infrequent generalized seizures occurred between four and seven. Diagnosis was first considered at the age of seven after neuroparalytic keratitis developed and rapidly became bilateral. This case has remained highly unusual throughout the course since none of the commonly reported complications (swallowing disorders, aspiration pneumonia, and dysautonomic "attacks") has occurred. No life-threatening manifestations have developed. Peripheral nerve biopsy specimens showed that myelinated fibers, especially of large diameters, were abnormally scarce, and that the histogram failed to exhibit the normal bimodal aspect. Ultrastructural studies also disclosed a marked reduction in the caliber of unmyelinated fibers, whose axons were flattened or occasionally missing. No evidence of regeneration was found. The atypical clinical features in our patient are discussed.

Ataxia↗
PubMed1989

Atrial refractory periods after atrial premature beats in patients with paroxysmal atrial fibrillation.

To study the effects of an atrial premature beat on atrial refractory periods, we investigated 11 patients (group A) who were the control group, 12 patients suffering from paroxysmal atrial fibrillation (group B), and 10 patients (group C) without arrhythmias but with cardiopathy or cardiomyopathy. At every eighth complex of a constant atrial electrostimulated rhythm a fixed premature extrastimulus was introduced, and effective and functional refractory periods (ERP and FRP) were measured in three different sites of the right atrium, before and after introduction of this extrastimulus. Average ERP and FRP shortened respectively in group A, from 220.28 +/- 25.68 msec and 281.17 +/- 28.15 msec before extrastimulation, to 190.58 +/- 22.74 msec and 245.88 +/- 19.86 msec after; in group B, from 219.44 +/- 27.38 msec and 284 +/- 30.06 msec to 191.66 +/- 28.72 msec and 253.23 +/- 34.01 msec; and in group C from 229.03 +/- 29.65 msec and 289.67 +/- 51.62 msec to 194.19 +/- 24.6 msec and 237.74 +/- 39.59 msec. The average dispersions of ERP and FRP in group A were, respectively: 41.81 +/- 21.36 msec and 36.36 +/- 18.04 msec before extrastimulation, 28.18 +/- 18.14 msec and 35.45 +/- 15.72 msec after. In group B: 26.66 +/- 19.46 msec and 41.66 +/- 16.96 msec versus 45.83 +/- 23.91 msec and 45 +/- 34.77 msec and in group C: 27 +/- 11.59 msec and 45 +/- 29.15 msec versus 29 +/- 18.52 and 27 +/- 18.88.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

A clinical study of the application of endocardial fulguration in the treatment of recurrent atrial flutter.

Endocardial catheter fulguration has been recently proposed for treatment of arrhythmias originating within the right atrium. In this study the authors attempted to use this technique in eight patients with paroxysmal common atrial flutter. Numerous antiarrhythmic agents failed to prevent recurrences of the episodes, which occurred frequently over periods of at least 4 months. In every procedure, we used a 7F quadripolar catheter electrode introduced via the subclavian vein into the lower part of the right atrium. The two distal electrodes allowed the recording of bipolar double potentials where the critical slow pathway of the reentrant circuit was localized. A unipolar electrogram recording by the tip electrode gave us the location of the area to be ablated when this electrogram was in complete concordance with a small step in the descending part of the F waves in II, III and aVF. This step corresponded to the very depolarization of the reentry area. A DC shock of 100 to 120 J was delivered between the tip electrode and a paddle applied to the left chest wall. Sinus rhythm resumed instantaneously. No mechanical or electrical complications were noted. Three patients are free of relapses without antiarrhythmic drugs (follow-up: 14 to 17 months); three others are also free of relapses, but antiarrhythmic agents were required for treatment of other supraventricular dysrhythmias (follow-up: 3 to 17 months); atrial flutter recurred within several days and persisted in spite of two more procedures in two patients. We conclude that endocardial catheter fulguration of paroxysmal and recurrent atrial flutter seems to be effective therapy. Nevertheless, more experience is required in order to confirm these results.

Aged↗
PubMed1989

Chronic relapsing idiopathic polyneuropathy with primary axonal lesions.

Idiopathic polyradiculoneuropathy with primary axonal lesions is rarely encountered. Two cases are reported with a chronic relapsing course and a fatal outcome. Neuropathological examination of biopsied peripheral nerve in the two patients and in a necropsy case showed loss of myelinated fibres, but neither active demyelination nor inflammatory cells were observed. Acute and chronic relapsing axonal polyradiculoneuropathies appear to be two clinical forms of a peculiar entity different from GBS.

Axons↗
PubMed1988

[Atypical muscular syndrome with myolysis during long-term treatment with fibrates].

Acute inflammatory muscular syndromes secondary to clofibrate therapy are rare. They usually present with muscular pain in all four limbs with biochemical signs of rhabdomyolysis. The outcome is favourable as a rule with rapid regression of the clinical and biochemical changes after stopping the responsible drug. The authors report an atypical case of this syndrome with chest pains suggestive of angina.

Clofibrate↗