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Phytanyl benzene and phytanyl toluene occur in mudstones from several key Permian-Triassic Boundary (PTB) sections from mid-northern palaeolatitudes (Spitsbergen and Eastern Greenland), as well as mid-southern palaeolatitudes (Western Australia). The occurrence of these compounds through the different PTB sections is related to the occurrence of the previously identified C33 n-alkyl cyclohexane, suggesting their parent organism shared a similar unique ecological niche and was associated with the extinction horizon. Further, the lack of these compounds in the carbonate-dominated palaeoequatorial, Global Stratotype Section and Point (GSSP), Meishan-1 (South China) section possibly points to their source being temperature and climate controlled.

SummaryWe evaluated two clinical scores for the prediction of deep venous thrombosis (DVT) in hospitalized patients (Wells’ and Kahn’s). We included 273 patients referred to the vascular exploration unit for the suspicion of DVT. A clinical questionnaire was filled in by the practitioner and the scores were calculated from this form. 66 of the 273 patients had a DVT. When Wells’ score was 3, a DVT was found by duplex echography in 51% patients ; when the score was 0, a DVT was found in 9%. Kahn’s score was not adapted to this population. We then developed a new simple score (cancer, palsy or plaster immobilization, warmth, superficial venous dilation, unilateral pitting edema, other diagnosis). A DVT was found in 76% patients with a score of 3 and in 11% in those with a score of 0. We therefore propose a 6-item score whose main advantages are simplicity and usefulness in routine practice.

Atrial fibrillation, the most common sustained cardiac arrhythmia and a major cause of stroke, results from simultaneous reentrant wavelets. Its spontaneous initiation has not been studied.We studied 45 patients with frequent episodes of atrial fibrillation (mean [+/-SD] duration, 344+/-326 minutes per 24 hours) refractory to drug therapy. The spontaneous initiation of atrial fibrillation was mapped with the use of multielectrode catheters designed to record the earliest electrical activity preceding the onset of atrial fibrillation and associated atrial ectopic beats. The accuracy of the mapping was confirmed by the abrupt disappearance of triggering atrial ectopic beats after ablation with local radio-frequency energy.A single point of origin of atrial ectopic beats was identified in 29 patients, two points of origin were identified in 9 patients, and three or four points of origin were identified in 7 patients, for a total of 69 ectopic foci. Three foci were in the right atrium, 1 in the posterior left atrium, and 65 (94 percent) in the pulmonary veins (31 in the left superior, 17 in the right superior, 11 in the left inferior, and 6 in the right inferior pulmonary vein). The earliest activation was found to have occurred 2 to 4 cm inside the veins, marked by a local depolarization preceding the atrial ectopic beats on the surface electrocardiogram by 106+/-24 msec. Atrial fibrillation was initiated by a sudden burst of rapid depolarizations (340 per minute). A local depolarization could also be recognized during sinus rhythm and abolished by radiofrequency ablation. During a follow-up period of 8+/-6 months after ablation, 28 patients (62 percent) had no recurrence of atrial fibrillation.The pulmonary veins are an important source of ectopic beats, initiating frequent paroxysms of atrial fibrillation. These foci respond to treatment with radio-frequency ablation.

Resume Nous rapportons huit cas de pneumopathie a l'amiodarone. La presentation clinique est dominee par une dyspnee aigue, subaigue ou progressive. La responsabilite de l'amiodarone est suspectee sur un faisceau d'arguments: des signes cliniques rarement au complet (dyspnee, fievre, toux), des signes radiologiques (TDM haute resolution qui montrent des images interstitielles ou alveolointestitielles asymetriques, souvent bilaterales, de forte densite scanographique), une hypoxemie, des anomalies de la cellularite au cours des lavages bronchoalveolaires (rarement specifiques) voire des arguments histologiques par biopsie pulmonaire. Il est surtout important d'eliminer toutes les autres causes possibles de pneumopathies subaigues ou chroniques en particulier neoplasiques, infectieuses ou liees a une insuffisance cardiaque. La dose cumulee d'amiodarone n'est pas determinante car certains cas surviennent precocement (1 a 2 mois) avec un tableau de dyspnee aigue febrile, parfois grave evoquant un mecanisme immunoallergique. La preuve de la responsabilite de l'amiodarone ne peut etre obtenue qu'avec l'arret du medicament; la disparition des symptomes cliniques et radiologiques est parfois retardee de 2 a 6 mois.

The possibility of curing patients suffering from paroxysmal atrial fibrillation using a radiofrequency ablation treatment is a major change in the management of this arrhythmia. Pulmonary vein disconnection is efficient and safe after a learning curve of the operator. This pulmonary vein isolation is the first and mandatory step allowing disappearance of atrial fibrillation in 70% of the patients. Modification in fibrillatory substrate using linear lesions increases the rate success to 75% in chronic atrial fibrillation and to 82% in paroxysmal atrial fibrillation. The radiofrequency ablation of atrial fibrillation should be considered as a surgical treatment without an open heart, isolating structures and cutting tissues are technical improvements (new radiofrequency catheters) will probably facilitate in the future. Some comparative studies with medical treatment are currently evaluating their efficacy, safety and respective cost and they may lead to a considerable increase in the number of patients who could benefit from these curative treatments.

Hemorrhagic complications are the most frequent complications of antivitamin K (AVK) treatments and can be life-threatening. We report 75 patients from a University Hospital. They were 40 males and 35 females (median age 74 years, 20-94), and were classified into 3 grades according to clinical picture: grade 1 (no surgery or transfusion, grade 2: surgery or blood transfusion needed, grade 3: death). 43 patients had grade 1 complications, 27 grade 2, and 5 grade 3 complications. The most frequent complications were muscular hematomas (36 patients), sub-cutaneous hematomas (14 patients), digestive bleeding (13 patients), hematuria (12 subjects). Eight patients had intracerebral bleeding, of whom 3 died. The treatment time was very variable (1 to 988 weeks). Only half patients had a prothrombin rate (PR) below 20% but two thirds had an INR above 5. This study showed that PR was a poor predictor of hemorrhagic complications. INR was a better parameter. For 15 patients, we considered that the indication was unadapted or questionable, among whom 2 died. This work suggests that the promotion of AVK prescription rules should go on.

Ablation of Paroxysmal Atrial Fibrillation. Introduction: (AF), trial fibrillation (AF), the most common arrhythmia, is due to multiple simultaneous wavelets of reentry in the atria. The only available curative treatment is surreal, using atriotomies to compartmentalize the atria. Therefore, we investigated a staged anatomical approach using radiofrequency catheter ablation lines to prevent paroxysmal AF. Methods and Results: Forty-live patients with frequent symptomatic drug-refractory episodes of paroxysmal AF were studied. Progressively complex linear lesions were created by sequential applications of radiofrequency current in the right atrium and then in the left atrium if required. The outcome of the procedure was considered a success when the episodes of AF were either eliminated or recurred at a rate of no more than one episode (lasting < 6 hours) in 3 months. Patients who had no more than one episode per month were considered “improved.” Right atrial ablation organized local electrical activity and led to stable sinus rhythm during the procedure in 18 (40%) of the 45 patients. However, sustained AF remained inducible in 40 of 45 patients, and the lesions failed to produce evidence of a significant linear conduction block/delay in all but four patients. There were no significant complications except for two transient sinus node dysfunctions. The procedure duration and fluoroscopic time were 248 ± 79 and 53 ± 11 min, respectively. Additional sessions were required in 19 patients to treat sustained right atrial flutter or arrhythmias linked to ectopic right or left atrial foci. During a mean follow-up of 11 ± 4 months, right atrial ablation was successful in 15 (33%) patients, ft without medication and 9 with a previously ineffective drug. Nine (20%) additional patients were improved. Ten patients with an unsuccessful outcome then underwent linear ablation in the left atrium. The procedure duration and fluoroscopy time were 292 ± 94 and 66 ± 24 min. A hemopericardium occurred in one patient. Two patients required reablation to treat ectopic atrial foci. Left atrial ablation terminated AF during the procedure in 8 patients, and sustained AF could not he induced in 5. Subsequent success was achieved in A (60%) patients, including 4 without medication, and 1 additional patient was improved. Conclusions: Successful radiofrequency catheter ablation of drug-refractory daily paroxysmal AF is feasible using linear atrial lesions complemented by focal ablation targeted at arrhythmogenic foci. Ablation only in the right atrium is a safe technique providing limited success, whereas linear lesions in the left atrium significantly increase the incidence of stable restoration of sinus rhythm, the inability to induce sustained AF, and the final success rate. The described technique is promising hut must he considered preliminary because significant Improvements are required to optimize lesion characteristics and shorten total procedure duration.

Atrioventricular nodal reentrant tachycardias which, for a long time, could only be treated medically, may now benefit from catheter ablation. The rapid retrograde pathway was an effective initial target but carried a risk of complete atrioventricular block of about 10%. Nowadays, most operators deliver the radiofrequency energy (endocavitary cautery) to the slow nodal pathway. Different techniques of guidance (anatomical, electrophysiological, rapid potential, slow potential) are associated with high success rates: 90 to 100%. However, experimental studies suggest that the slow potentials arise from transitional cells within the tachycardia circuit (the anatomical substrate of the slow pathway). There is still a risk of complete atrioventricular block (1 to 5%) which should be clearly explained to patients referred for ablation of this constantly benign arrhythmia.

The incidence of sudden death in the Wolff-Parkinson-White (WPW) syndrome is not well documented and probably underestimated. This retrospective study concerned 28 consecutive patients presenting with ventricular fibrillation either spontaneously (20) or during electrophysiological investigation (8) but whose characteristics allowed them to be assimilated into a single group. Their clinical and electrophysiological characteristics were compared with those of 60 consecutive patients with the WPW syndrome who had documented atrial fibrillation (and even reciprocating tachycardia) but never ventricular fibrillation. There were no significant differences between the two groups with respect to the following clinical parameters: sex, duration of symptoms, the type of tachycardia previously recorded, history of syncope and presence of underlying cardiac disease. With respect to the electrophysiological data, there were no differences in the point of anterograde block, the effective anterograde refractory period of the accessory pathway, the effective and functional refractory periods of the right atrium and atrial vulnerability. On the other hand, a significant difference was observed in the age of patients with ventricular fibrillation (29 +/- 13 years vs 36 +/- 12 years; p0.02), the prevalence of multiple accessory pathways (25% vs 7%; p0.04) with a dominant localisation in the postero-septal region (75% vs 47%, p0.026), preexcitation during exercise stress testing and under antiarrhythmic therapy (95% vs 68%, p0.037). The most discriminating parameter was the shorter RR interval during atrial fibrillation (172 +/- 23 ms vs 230 +/- 50 ms, p0.008). Multivariate analysis only showed one independent predictive factor: the minimum preexcited RR interval.(ABSTRACT TRUNCATED AT 250 WORDS)

Junctional tachycardias may be related to intranodal reentry or to the existence of an accessory pathway. All are suitable for radical treatment by radiofrequency current applied either in the perinodal region or at the tricuspid or mitral atrioventricular rings respectively. 176 patients with intranodal reentry were treated by preferential modification of the rapid (8) or slow (167) anterograde pathway of the reentry circuit, with a 99% success rate (1 failure) and without significant complications, in particular atrioventricular block in the case of ablation of the slow pathway. 362 patients with one or more accessory pathways, patent or latent, were treated using the same type of energy. The ablation site was determined on the basis of indirect criteria and/or recording of the specific activity of the accessory pathway. The success rate here was 98%, once again without significant complications with the exception of those inherent to catheterisation procedures. Treatment duration time was 41 +/- 38 min in the treatment of intranodal reentry and 58 +/- 49 when one or more accessory pathways were responsible. X-ray exposure times were 14 +/- 14 min and 23 +/- 21 min respectively. Such results would justify the expectation of widened indications of the method.

Junctional tachycardias are among the most frequent or paroxysmal supraventricular tachycardias. They are due to a reentry mechanism and include the so-called nodal reentrant tachycardias as well as tachycardias which imply a patent or hidden accessory pathway. The prognosis of these tachycardias is usually benign, but it can be made unfavourable by repeated attacks or by the presence of an accessory pathway with short anterograde refractory period which exposes the patient to severe arrhythmia. Clinicians are now provided with a therapeutic armentarium that enables them to reduce easily any attack of junctional tachycardia, but also to prevent recurrences. The intracavitary ablation technique by application of radiofrequency currents ensures the radical cure of recurrent or threatening arrhythmias by suppressing the indispensable anatomical substrate of tachycardias.

We report on eight cases of amiodarone pulmonary toxicity. Main clinical symptoms are acute/subacute dyspnea or progression in some cases. Amiodarone responsibility is difficult to ascertain. Several arguments can be presented: clinical symptoms with dyspnea and/or fever and/or cough, interstitial or in diffusing capacity for carbon monoxide, abnormal broncho-alveolar lavage cytopreparation smear with increased percentage of lymphocytes and polymorphonuclear leucocytes in typical cases; trans-bronchoscopic lung biopsy failed to provided information on amiodarone toxicity in the two patients where biopsy were performed. Differential diagnosis is an essential step to eliminate other possible causes ie pulmonary micro-organism infections, cancer or pulmonary oedema secondary to heart failure. In one case acute pulmonary toxicity occurred early, after introduction of amiodarone, with a proposed immuno-allergic mechanism. In other cases, chronic amiodarone deposition in the lungs can explain clinico-radiologic features. In six cases improvement was observed after discontinuation of therapy within a 6-months period.

Atrioventricular nodal tachycardias due to intranodal reentry or to an accessory pathway are accessible to radical cure with radiofrequency currents applied either at the site of recording of characteristic slow potentials or at the tricuspid or mitral atrioventricular rings. One hundred and six patients with atrioventricular nodal reentry were treated by modification of the slow anterograde reentrant pathway with a 100% success rate and without any serious complications (especially atrioventricular block). One hundred and eighty six patients had one or more overt or latent accessory pathways and were treated by the same method. The ablation site was decided on indirect criteria and not by the recording of the specific activity of the accessory pathway. The success rate was 97%, also with no significant complications. The duration of the treatment was 41 +/- 22 min for the accessory pathways. The exposure time to ionising radiation was 14 +/- 14 min and 31 +/- 34 min respectively. These results suggest that the indications of radiofrequency current ablation could be extended.

Arrhythmogenic dysplasia of the right ventricle is a common cause of ventricular arrhythmia. It is important to reach a diagnosis, due to the risk of sudden death, particularly as this may be the first sign of the disease. Diagnosis is based on the angiographic demonstration of a morphological or structural abnormality of the right ventricle, and non-invasive tests are relatively insensitive. From a case investigated in 1984, the authors carried out a prospective determination of the diagnostic value of the isoprenaline test in 61 patients suffering from arrhythmogenic dysplasia of the right dysplasia confirmed by angiography. High concentrations (8-30 micrograms/min) of isoprenaline were continuously infused over a period of 3 minutes, regardless of the heart rate achieved. In a control group of 50 subjects with no myocardial disorder, isoprenaline induced monomorphic wave-burst arrhythmia in only one patient (2%). In the subjects affected by right ventricular arrhythmogenic dysplasia, isoprenaline induced one or more episodes of wave-burst ventricular arrhythmia in 52 patients (85%): one triplet in four patients, several episodes of wave-burst arrhythmia in 31 patients and prolonged ventricular tachycardia in 17 patients. Polymorphic arrhythmia occurred in 80% of cases, but left lag forms predominated. High-amplification ECG demonstrated late potentials in 66% of cases, i.e. in 80 and 62% of patients with and without prolonged VT respectively. The isoprenaline test or high-amplification ECG gave abnormal results in 58 of the 61 patients, with a cumulative sensitivity of 95 percent.

Several epidemiological studies have shown decreased cardiovascular mortality and a lower incidence of coronary artery disease in subjects with high dietary intakes of Omega-3 polyunsaturated fatty acids. It has since been shown that Omega-3 fatty acids have a number of beneficial effects in the prevention of atherosclerosis in man: reduction of blood pressure, modifications of lipoprotein metabolism, modifications of haemostasis (increased bleeding time and reduced platelet aggregation), decreased plasma fibrinogen, modifications of the metabolism of arachidonic acid and its derivatives (decreased thromboxane and leukotriene synthesis, increased prostacyclin synthesis). Therefore, Omega-3 polyunsaturated fatty acids have several beneficial effects on the presumed mechanisms of atherogenesis and/or its complications: they could represent an original and seductive solution to the problem of prevention of cardiovascular disease.

Primary cardiac leiomyosarcoma is a very rare condition. Only 15 cases have been reported in the literature. We report the case of a 27 year old man admitted to hospital for chest pain in March 1985. Echocardiography showed a right ventricular tumour which was completely resected at surgery. The diagnosis of leiomyosarcoma was confirmed by histological examination. After 22 months follow-up, the patient was still alive despite pulmonary metastases. The diagnosis of cardiac tumour used to be made post-mortem but since the introduction of new methods of investigation, especially 2D echocardiography, the diagnosis can be made at an early stage and allows rapid surgical resection, the only means of obtaining the histological diagnosis and of completely curing benign tumours.

Three cases of long QT-interval due to halofantrine were documented in 1992 in France. Two of them had a congenital long QT-interval (Romano-Ward syndrome). We performed a prospective study of cardiac monitoring in 20 patients taking halofantrine. Minimal ECG changes were noted with lengthening of the QT-interval. Systematic ECG is necessary before giving halofantrine.

Cardiac myxoma is an intracavitary neoplasm. Only 5% are found in the right of left ventricle. Classically, myxoma presents as constitutional, embolic or obstructive symptoms. The authors report a case of ventricular cardiac myxoma revealed by rheumatological signs.

The success rate of catheter ablation, the latest therapeutic method in the treatment of cardiac arrhythmias, varies according to the precise indication. The best and most logical guarantee of its efficacy is the application of the electrical energy at an anatomical site essential to the arrhythmia. In preexcitation syndromes this site is without doubt the accessory pathway itself rather than its insertions, but this implies the recording of its activation. We recorded the electrical activation of a right sided Kent bundle in three consecutive cases to guide the therapeutic procedure (comparable to the recording of the H potential for his bundle ablation). All patients had paroxysmal atrial fibrillation (minimal RR interval: 175, 150 and 200 ms) and orthodromic reciprocating tachycardia. Two patients had had attacks of ventricular fibrillation. The sites of the Kent bundles were posteroseptal in 2 cases and anterolateral in 1 case. The recording of the electrical activation of the Kent bundle was validated by: the passage (induced or spontaneous) of a preexcited to a normal QRS coincident with the disappearance of the K potential; the exclusion of an atrial or ventricular origin of the electrical activation supposed to be the activation of the Kent bundle; electrical stimulation at the site of the recording of the K potential leading to prolongation of the stimulus-delta wave interval from 10 to 35 ms, with QRS morphology identical to the spontaneous complexes. All 3 patients were clinically cured by catheter ablation at the site of recording of the Kent bundle activation with follow-up periods ranging from 10 to 16 months.(ABSTRACT TRUNCATED AT 250 WORDS)