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The authors recently reexamined the peripheral nerve biopsies from 42 patients with chronic inflammatory demyelinating polyneuropathy (CIDP). There were 27 males and 15 females, aged from 9 to 84 years, and 13 had relapses. No patient had vasculitis, monoclonal gammopathy, tumor, diabetes mellitus, Lyme disease, familial neuropathy, HIV, or any other immune deficiency. In the endoneurium, perivascular inflammatory cell infiltrates were present in only one case, but scattered histiocytes marked by KP1 on paraffin-embedded fragments were present in every case and there were no T-lymphocytes. At ultrastructural examination macrophage-associated demyelination was observed in 17 cases, of which 6 had relapses separated by intervals of several months or years. Axonal lesions without associated primary demyelination were observed in 4 cases and 3 of these had relapses. Thirty-two patients had mixed lesions of demyelination and axonal involvement. This study confirms other recent data indicating that in all cases of CIDP, macrophages are present in the endoneurium. Macrophage-associated demyelination is the characteristic feature of demyelinating forms. On the other hand, isolated primary axonal forms, which have been known since 1989, are relatively frequent and prone to relapses. [ABSTRACT FROM AUTHOR]

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: 24 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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The atrio-His bundle tracts are very rare; only two have been found in 687 hearts studied histologically. These tracts have a similar appearance to those of the atrioventricular bundle and form a complete bypass of the atrioventricular node. In their presence the electrocardiogram may show a short or normal PR interval. They may be responsible for some cases of very rapid ventricular response to supraventricular arrhythmias. [ABSTRACT FROM PUBLISHER]

We reviewed 202 biopsies performed on patients with suspected vasculitic neuropathy, of which 24 Churg-Strauss cases are studied separately. Specimens from the superficial peroneal nerve and peroneus brevis muscle were taken simultaneously by one incision. Without taking into account constitutional signs, systemic involvement was present in 131 patients, whereas the remaining 47 corresponded to non-systemic patients with lesions limited to peripheral nervous system and adjoining muscles. Diagnosis of panarteritis nodosa or microscopic polyangiitis, according to the size of involved vessels, was attested by an infiltration of vessel walls by inflammatory cells associated with fibrinoid necrosis or sclerosis. Microvasculitis was diagnosed when inflammatory infiltration concerned small vessels with few or no smooth-muscle fibers and without any necrosis. Microvasculitis was present in 11 of 46 non-systemic cases, and this predominance is statistically significant. Isolated perivascular cell infiltrates in the epineurium were considered not significant but allowed the diagnosis of 'probable vasculitis' if associated with at least one of the following features: regenerating small vessels, endoneurial purpura, asymmetric nerve fiber loss, and/or asymmetric acute axonal degeneration. Necrotizing vasculitis was visible in 60 cases: in nerve (16 cases), in muscle (19 cases), and both (25 cases). Microvasculitis was present in 25 cases: in nerve (19 cases), muscle (four cases), or both (two cases). Moreover, granulomatous vasculitis was found in the nerve of one non-systemic patient presenting also sarcoid granulomas in muscle. There were 24 'probable vasculitis' and 68 negative cases. Muscle biopsy improved the yield of definite vasculitis by 27%.

We examined nerve biopsies from 24 patients with Charcot-Marie-Tooth disease type 1A (CMT1A) and proven 17p11.2-12 duplication. There were seven males and 17 females with a mean age of 27.85 +/- 18.95 years at the time of nerve biopsy. A family history consistent with dominant inheritance was present in 17 patients. Clinical features were classical in 16 patients and were atypical in the other eight: one had calf hypertrophy; two had Roussy-Levy syndrome; one had had a subacute inflammatory demyelinating polyneuropathy 11 years earlier and presented a relapse on the form of a chronic inflammatory demyelinating polyneuropathy; one had carpal tunnel syndrome; one had a recent painful neuropathy in both legs; and two had chronic inflammatory demyelinating polyneuropathy. Onion bulb formations (OMFs) were present in every case and most of them were characteristic, whereas burnt-out or cluster-associated OMFs were less common. Depletion of myelinated fibers was severe in 20 cases (169-2927/mm2) and varied from 5187 to 3725/mm2 in three children (4-9 years old). In addition, features of macrophage-associated demyelination were observed in the last four atypical cases. Known for more than 20 years, inflammatory demyelination superimposed in the course of CMT1A has been reported in a few cases in the past few years, mainly concerning asymptomatic or atypical patients. Such an association deserves to be better known because corticotherapy improves weakness in most of these patients.

We performed a retrospective study of 35 peripheral nerve biopsies (PNBs) with amyloid deposits in the endoneurium. In every case, nerve lesions were studied on paraffin-embedded fragments (PEFs) and by ultrastructural examination (USE). In addition, muscle fragments were taken and embedded in paraffin. Immunohistochemistry was performed with anti-transthyretin (TTR) serum on 19 nerve and 15 muscle PEFs. Direct immunofluorescence with anti-light-chain sera was performed on frozen nerve fragments in 19 cases. Endoneurial amyloid deposits were easily identified on routine PEF in 26 cases, after Congo red or thioflavine staining in three, and by USE in six. A dramatic myelinated fiber loss was evidenced in 34 cases (77-2970 per mm2), and features of axonal degeneration were present in every case. Segmental demyelination was observed in 10 cases. A mutation in the TTR gene was present in 14 cases, with Met30 mutation in 10 and Ala49 in four members of the same family. Amyloid deposits were strongly marked by the anti-TTR serum in 11 other cases, twice in the endoneurium, five around muscle fibers, and four in both locations. In eight patients, light-chain positivity was evidenced in endoneurial deposits, lambda in six and kappa in two. Two other patients with monoclonal gammopathy did not present any light-chain fixation. In 17 cases, amyloidosis was disclosed by PNB and 13 had a TTR pathology; eight of them, over 65 years old, correspond to a late-onset form of familial amyloid polyneuropathy which is an underdiagnosed condition.

In most cases of hereditary neuropathy with liability to pressure palsy (HNPP) the diagnosis is now assessed by molecular detection of 17p11.2 deletion. However, the family history may be missing and the clinical presentation is not always informative. In such cases, a peripheral nerve biopsy showing the characteristic focal myelin sheath thickening ("tomaculae") may be helpful. We present a retrospective study of peripheral nerve biopsies performed in 19 patients suffering from either a mononeuropathy or a generalized sensory-motor polyneuropathy, and for whom the finding of tomaculae led to a search for 17p11.2 deletion, which was confirmed secondarily. Tomaculae and other coexisting neuropathological lesions such as uncompacted myelin, "onion bulb" formations, and axonal degeneration are described and discussed in the view of previously reported data. It appears that demyelinating lesions with tomaculae are strongly suggestive of HNPP but are not specific as they may be observed in other conditions. Moreover, these features may be overlooked if axonal degeneration is marked.

The pathogenesis of Crow-Fukase (POEMS) syndrome is not well known, and in some cases, a definite diagnosis is difficult to establish. Nerve fibers have been studied in about 120 peripheral nerve biopsies (PNBs), and a mixture of axonal and demyelinating lesions were found in most of them. We report five new cases of Crow-Fukase (POEMS) syndrome with ultrastructural examination of their PNBs. In every case, there were features of axonal degeneration and primary demyelination. Interestingly, uncompacted myelin lamellae (UMLs) were present in every case at a percentage of 1-7. The association of UML and Crow-Fukase (POEMS) syndrome was described 20 years ago but was only reported in a few studies and found in 31 of 41 cases. In fact, this association is very significant because apart from Crow-Fukase (POEMS) syndrome, UMLs can only be found with such a frequency in rare cases of Charcot-Marie-Tooth disease type 1B. UML was also reported in acute and chronic inflammatory demyelinating polyneuropathies but at a much lower percentage. Moreover, in our five cases, UML was frequently associated with a decrease in the number of intra-axonal filaments, and this finding raises the problem of relationships between myelin formation and neurofilaments. So far, glomeruloid hemangiomas present in the dermis of some patients are considered as the only specific criteria of Crow-Fukase (POEMS) syndrome, but we think UML can also be regarded as highly suggestive of this entity on condition that a thorough ultrastructural examination of a PNB is performed.

Since 1979, the authors have studied 49 peripheral nerve biopsies presenting uncompacted myelin lamellae (UML). Based on the ultrastructural pattern of UML they propose a 3-category classification. The first category includes cases displaying regular UML, which was observed in 43 cases; it was more frequent in 9 cases with polyneuropathy organomegaly endocrinopathy m-protein skin changes (POEMS) syndrome as well as in 1 case of Charcot-Marie-Tooth 1B with a novel point mutation in the P0 gene. The second category consists of cases showing irregular UML, observed in 4 cases with IgM monoclonal gammopathy and anti-myelin-associated glycoprotein (MAG) activity. This group included 1 benign case and 3 B-cell malignant lymphomas. The third category is complex UML, which was present in 2 unrelated patients with an Arg 98 His missense mutation in the P0 protein gene. Irregular and complex UML are respectively related to MAG and P0, which play a crucial role in myelin lamellae compaction and adhesion.

Intracellular pH was measured with the pH-sensitive fluorescent probe BCECF in spinal cord neurones cultured from rat embryos. At an external pH of 7.3, the average steady-state pHi was 7.18 +/- 0.03 (SEM, n = 97) and 7.02 +/- 0.01 (n = 221) in HEPES-buffered and in bicarbonate-buffered medium, respectively. In both external media, pHi was strongly dependent on external pH (pHe). In HEPES-buffered medium, pHi recovery following an acid load induced by transient application of ammonium required external Na+ and was inhibited by amiloride, indicating the presence of a Na+/H+ exchange. Na(+)- and HCO3(-)-dependent, DIDS-sensitive alkalinizing mechanisms also contributed to pHi regulation in CO2/bicarbonate-buffered medium. The presence of an electrogenic Na(+)-HCO3- cotransporter was confirmed by the alkalinizing effect of KCl application. The fact that pHi is lower in CO2/bicarbonate- than in HEPES-buffered medium and the alkalinization observed upon suppression of external Cl- suggest that the acidifying Cl-/HCO3- transporter plays an important role in defining pHi.

Background: This study determined the histological features of the atrial myocardium connecting the coronary sinus and the left atrium in humans., Methods and Results: Ten necropsied hearts were studied by performing serial longitudinal sections parallel to the long axis of the coronary sinus that extended its full length using a large microtome. In all specimens, the venous wall of the coronary sinus was surrounded by a cuff of striated muscle extending 40+/-8 mm from the ostium. Striated myocardial connections of varying number and morphology left this coronary muscle cuff and connected to the left atrium; they ranged from 1 to 2 fascicles to a widely intermingled continuum (thickness, 2.79+/-2 mm; width, 2.91+/-3.5 mm). These connections originated 8.8+/-5.7 mm from the coronary sinus ostium and inserted 18+/-11 mm distally into the left atrium. The insulating compartment in which the connections traversed between the left atrium and the coronary sinus was mostly formed of adipose tissue. The valve of Vieussens was found in 6 hearts at a mean distance of 3.4+/-3.2 mm from the distal extremity of the coronary sinus muscle cuff., Conclusions: In the human heart, a consistent but morphologically variable left atrial coronary sinus myocardial connection was found. This emphasizes the need for surgical dissection or catheter ablation in or around the coronary sinus to eliminate these connections.

The study of heart rate variability allows analysis of modulations of heart rate by the sympathetic vagal system. The authors studied the course of sinus variability by 24-hour Holter monitoring preoperatively, and on the 6th and 42nd postoperative day, in 25 patients undergoing coronary bypass graft (group I) and 10 patients undergoing aortic valve replacement (group II). Surgery was performed under cardiopulmonary bypass with selective antegrade cold crystalloid cardioplegia. The preoperative ejection fraction of these patients was 62% with a mean age of 59.5 years in group I and 61.5 years in group II. All temporal or spectral parameters were significantly decreased in the two groups on the sixth day (p < 0.05). Parameters which remain altered on D42 compared to baseline values were temporal parameters: pNN50 and rMSSD for group I and ASDNN for group II, with a tendency to return to baseline values, but with a higher mean heart rate in group II on D6 and D42 (p < 0.05). In the spectral domain, TP (total power of the spectrum) and LF (Low frequencies) remained decreased in both groups. A reversible alteration of sinus variability parameters was therefore observed in the two groups of patients. Other studies are necessary to define the mechanisms of these alterations, which are most probably related to catecholaminergic flooding related to CPB or partial vagal denervation by ischaemic or surgical damage to nerve structures.

Supraventricular arrhythmias are frequently observed in pneumonectomy surgery. We retrospectively studied a series of 100 consecutive patients undergoing pneumonectomy for cancer between 1994 and 1996. We found 24% of significant supraventricular arrhythmias, corresponding to atrial fibrillation in 75% of cases, occurring in 80% of cases until the third postoperative day. The only risk factor significantly associated with these arrhythmias was the patient's age. These arrhythmias are easily reduced, spontaneously in 25% of cases, and usually by amiodarone, alone or associated with digitalis alkaloids. While the mortality of the overall group was 12%, 8% of patients with arrythmia died. These deaths concerned patients whose arrythmias occurred after the fourth postoperative day in a context of a pulmonary infection.

Anatomopathological studies have considerably increased our understanding of the ablative technique by radiofrequency current. They have provided information on the nature, extent and time dependency of the lesions induced. Despite variable results according to whether the experiments were performed in vitro or in vivo, a correlation has been observed between the volumes of the lesions and the energies used. One factor is unquestionable: monitoring the temperature allows better control of the lesion size than monitoring current intensity. However, other technical points are essential for this control such as ensuring good contact between the catheter and the endocardium and the definition of the optimal surface area of the electrode. Now that the conditions of efficacy and security of ablation by high frequency currents are known, anatomopathological studies in man have become rare. These studies, which will take a long time to perform due to the very nature of the technique and pathologies treated, should provide interesting anatomo-electrical comparisons to increase our understanding of certain arrhythmias.

Several studies have shown that high amplification and averaging of the electrocardiographic P wave may soon enable better identification of people at high risk of paroxysmal atrial fibrillation. The results of this technique are closely dependent on the conditions of recording and analysis of the atrial signal but this factor has not been widely appreciated. The authors, therefore, undertook a study of the reliability of the manual method of measuring P wave duration, the influence of the filters used and the level of background noise on the 3 parameters of analysis: the duration of the P wave (DUR), the root mean square of the amplitude of the terminal 20 milliseconds (RMS20) and the integral under the P curve (IN). The recorder was a Predictor II 5.0 (Corazonix) with a special programme to identify and analyse the P wave in 3 bipolar non-orthogonal leads. DUR was determined manually after amplification and averaging; RMS20 and IN were calculated automatically. In order to assess the reliability of manual determination of the P wave, 48 consecutive patients were studied: two analyses were made with a least a 2 months' interval by entering the data through two filters (unidirectional and FIR). The role of the filters was then studied by passing the preceding 48 recordings to an analysis with three filters: unidirectional, bidirectional and FIR, and comparing the results.(ABSTRACT TRUNCATED AT 250 WORDS)

The thrombogenic risk of contrast agents in coronary angiography is still a topical issue, particularly in comparisons between ionic and nonionic contrast agents. As a complement to a preliminary study, the repercussions on sensitive markers of haemostasis were investigated in vivo in 38 patients undergoing a standard cardiac catheterisation. After randomization, an ionic low osmolality contrast agent (Ioxaglate 320) was used in 19 patients and a nonionic low osmolality contrast agent (Iopromide 370) was used in another 19 patients, according to an identical protocol. The following parameters were assayed in arterial blood samples obtained before and after the examination in each patient: platelet markers: beta-thromboglobulin (beta TG) and platelet factor IV (PF4); prethrombotic markers: thrombin-antithrombin 3 complex (TAT) and prothrombin fragments 1 and 2 (F1 + 2) as well as partial exploration of fibrinolysis: tissue plasminogen activator inhibitors (PAI). Comparison of the results demonstrated platelet activation and the presence of prethrombotic markers in both groups. No significant difference was detected between the two groups of patients. Consequently, there does not appear to be any difference in activation of coagulation between modern, low osmolality, ionic or nonionic contrast agents. This may suggest an equivalent thrombogenic risk.

We report a case of aneurysm of all three aortic sinuses. The patient suffered from both cardiac failure and angina pectoris. The diagnosis, suggested by echocardiography, was confirmed by magnetic resonance imaging (MRI) which showed marqued dilatation of all three aortic sinuses. At operation, we observed dilatation of all three aortic sinuses, measuring 2 to 6 cm and partially thrombosed. We performed a Bentall operation with reimplantation of the left coronary artery ostium. The right coronary ostium was thrombosed and was revascularized by a saphenous vein bypass. Despite prolonged circulatory assistance and an intra-aortic balloon counterpulsation, cardiopulmonary bypass could not be stopped and the patient died. This is a new case of multiple aneurysms of the aortic sinuses and also a case of aortic sinus aneurysm (ASA) complicated by coronary insufficiency. This last complication has a poor prognosis, as demonstrated by a review of the 28 cases described in the literature. MRI was found to be important for the diagnosis of the ASA, in combination with echocardiography and angiography which can underestimate the aneurysm because of the frequently associated mural thrombus.

Among the drugs recommended to prevent recurrences of atrial fibrillation after external electric shock, antiarrhythmic agents of classes Ia (quinidine, disopyramide), Ic (cibenzoline, flecainide, propafenone) and III (sotalol) seem to have the same effectiveness in maintaining the sinus rhythm in about 50 percent of the cases after 6 months and one year. Amiodarone, seldom used as first-line treatment, appears to be the most effective drug. The percentage of side-effects requiring discontinuation of treatment is the same for all drugs (about 10 percent). All these drugs have potential proarrhythmic effects. In case of recurrence electric shocks can be repeated in some special cases. The therapeutic strategy according to the clinical context (atrial fibrillation of vagal nerve or catecholergic origin, normal or altered left ventricular function) is discussed.