[Pharmacological treatment of ventricular tachycardia]. / Traitement pharmacologique des tachycardies ventriculaires.

Pharmacological antiarrhythmic therapy is the treatment of first intention for the prevention of ventricular tachycardia (VT). In sustained VT, electrophysiological investigations without treatment enable the induction of VT, the demonstration of its reproducibility, the confirmation of diagnosis (if necessary), the determination of its mechanism and the choice of treatment. In an effort to standardise the technique, a minimum acceptable protocol of stimulations was agreed upon: at least 2 cycles (600 milliseconds and 400 milliseconds) and 3 extrastimuli (S2, S3, S4). The percentage of inducibility (sensitivity) depends on the underlying heart disease and is of the order of 90-95% in coronary artery disease with a history of infarction. Serial electrophysiological studies show non-inducibility of VT with treatment in 20-60% of cases. This result is influenced by the ejection fraction, the type of ventricular arrhythmia (fibrillation or tachycardia) and the antiarrhythmic agent tested. A Class IA, then a Class IC antiarrhythmics or sotalol (if the ejection fraction is over 40%) are evaluated by this technique. Empiric therapy has no place in the management of malignant poorly tolerated arrhythmias. In recurrent, well tolerated arrhythmias which are non-inducible, treatment may be guided by the results of Holter monitoring, providing the patient has a sufficient number of extrasystoles. Exercise stress tests may be useful in effort or catecholamine-induced tachycardias. There is no consensus about the management of non-sustained VT. When these arrhythmias are associated with syncope or cardiac arrest, programmed ventricular stimulation seems indicated. The choice of antiarrhythmic drugs and their results are reviewed.

[Urokinase recanalization of extensive thrombosis of the superior vena cava secondary to an implantable perfusion device]. / Reperméabilisation par urokinase d'une thrombose extensive cave supérieure sur boîtier de perfusion implantable.

A superior vena cava syndrome developed suddenly in a 36 year old man who had been undergoing chemotherapy via an implanted venous access catheter for 18 months. Venography showed superior vena cava thrombosis extending bilaterally to the subclavian veins. Direct local thrombolysis with low-dose Urokinase resulted in partial recanalisation with an excellent clinical result despite the persistence of an endovenous sequestrum situated at the catheter tip, a sequela of previous thrombosis. This case underlines the importance of direct local thrombolysis in patients with a Port-a-Cath system complicated by a thrombosis.

[Atrioventricular block at nodal and infrahissian level during atrial tachycardia. Apropos of a case]. / Bloc auriculo-ventriculaire à l'étage nodal et infrahissien, au cours d'une tachycardie atriale. A propos d'un cas.

The authors report the case of a patient with atrial tachycardia and surface electrocardiographic signs of left anterior hemiblock and complete right bundle branch block with 10/3 atrioventricular block. The regularity of the RR intervals which were an exact multiple of the atrial cycle suggested the absence of a Wenckebach phenomenon. The sequence of atrioventricular conduction cannot be explained by classical models of intranodal conduction. Endocavitary recordings confirmed this hypothesis. They showed block at 2 levels: supra- and infrahisian. The suprahisian block functioned in the 2/1 mode and the infrahisian block in the 5/3 mode without incremental conduction distal to the His potential before the apparition of block. A double zone of intrahisian block could explain the observed sequence of atrioventricular conduction. The absence of Wenckebach phenomenon on the surface ECG during tachycardia could be a sign of infrahisian block. The authors suggest that the association of this sequence of atrioventricular conduction with intraventricular conduction defects is a formal indication for electrophysiological studies.

[Atrioventricular block, a complication of radiotherapy of the mediastinum]. / Bloc auriculo-ventriculaire, complication de la radiothérapie du médiastin.

Cardiac complications of mediastinal irradiation usually concern the pericardium, the ventricular myocardium and the coronary arteries. We report the case of a 42-year old woman who experienced a syncopal atrioventricular (AV) block 12 years after irradiation of a mediastinal Hodgkin's lymphoma. Electrophysiological recordings showed infranodal conduction disturbances. A review of the literature yielded only 12 cases of syncopal radiation-induced AV block. This case highlights the risk of syncopal AV blocks occurring a long time after mediastinal irradiation and leading to severe damage of the His bundle and its branches. The presence, as in our patient, of an associated right ventricular outflow tract stenosis confirms the importance and severity of radiation-induced cardiac lesions.

[Pulmonary hypertension secondary to talc microemboli in a HIV seropositive heroin-addict woman]. / Hypertension artérielle pulmonaire secondaire à des micro-emboles de talc chez une héroïnomane séropositive au virus immunodépresseur humain.

Severe pulmonary hypertension presenting as acute cor pulmonare was observed in a HIV positive heroin addict. The usual aetiological investigations were negative. The apparently primary pulmonary hypertension was resistant oxygen and vasodilator therapy and was fatal in 6 months. Anatomopathological examination revealed the presence of talc microemboli in the pulmonary arterioles, severe medial hypertrophy and fibrous subendothelial thickening. The presence of the talc suggests that the pulmonary hypertension in this case was due to obstruction of the pulmonary vascular bed by the obstructive arterial lesions, despite the context of HIV infection.

[Epidemiologic aspects of polyarterial pathology]. / Aspects épidémiologiques de la pathologie polyartérielle.

UNLABELLED: With the considerable technical progress in vascular investigations made in the last decade, evaluation of multifocal ischemic pathology (MIP) has become easier and allows better assessment of strategy for reperfusion. In vascular surgery, 50% of post-operative mortality and morbidity are related to coronary heart disease (CHD). Epidemiologic data, not biased by specific recruitment of medical and surgical departments, are needed to assessing the real incidence of MIP. Different clinical date have already shown the problem of MIP: the post-operative cardiac mortality rate in vascular surgery has been evaluated at between 0.9% and 3.5% for abdominal aortic aneurysms and 0.3% and 3.2% for peripheral vascular disease (PVD) according to recent statistics (2, 7, 10, 12, 21) (Table I). The total cardiac mortality rate is between 1% and 2% for vascular surgery and is 0.2% for general surgery (8). Thus, though early post-operative over-risk in vascular surgery is not very high, the long term-prognosis is far more impaired: 25% to 55% of patients will die within 10 years after vascular surgery (4, 10, 13, 20). Hertzer, using systematic pre-operative coronary angiograms, found significant coronary stenosis in 57% of patients referred for vascular surgery (11). POPULATION AND METHODS: This study was performed in a representative sample taken from an ongoing prospective survey of 10,446 council employees in Marseille (5,177 men (M.), 5,269 women (W.)). This sample of 1,883 M. and 1,212 W. (mean age: 42.3 +/- 9 for M., 44.9 +/- 11 for W., range 25-65 years) was submitted to a detailed questionnaire on personal and family history of CHD, risk factors and symptoms of CHD (22), and to a physical examination including height, weight and blood pressure measurements. Every subject underwent an ECG recording and a dietetic (5) and psychologic (1) interview, and a blood sample was taken for plasma glucose, total cholesterol and lipoprotein assay. According to epidemiologic data, the prevalence of MIP appears to be lower as compared to clinical data. Undoubtedly, clinical data from surgical departments overestimate the true prevalence of MIP since patients referred for surgical therapy are usually suffering from more advanced pathology. Epidemiology, mainly based on non invasive data probably underestimates the prevalence of MIP but confirms the highest prevalence of CHD as compared to prevalence of other localisations of atherosclerosis and shows CHD as being the earliest localisation of vascular ischemic lesions in most cases. When unifocal ischemic pathology (UIP) and MIP are compared, risk factors are the same, although different proportions of patients are concerned with some of them: in MIP, age is still the major risk factor, whereas smoking in M. and overweight in W. seem to be more frequent than in UIP. RESULTS: Sixty-eight cases (5%) of ischemic pathology were found in men and 47 cases (4%) in women, with 4.1% cases of unifocal ischemic pathology (UIP) in M. and 3.3% in W...

[Polyarterial pathology. Epidemiological aspects]. / La pathologie polyartérielle. Aspects épidémiologiques.

Polyarterial arteriosclerosis is a problem facing more and more clinicians because of the technical advances in exploration and revascularization methods. Epidemiologic data are rare in this field except for Framingham's study. We are reporting here the results of a French epidemiologic study regarding a representative sample of a group of 11,000 active men and women, with age ranging between 25 and 65 years. Methodologic difficulties cannot be avoided, but a minimal estimation may be expressed: polyarterial pathology represents approximately 15 p. cent of the pathology in each case. Polyarterial pathology is as prevalent as monoarterial pathology with a 10 years delay between the two sexes. Coronary diseases are the most frequent and represent the initial location in two-thirds of the cases. The same risk factors are found, but their chronology is different: more than ever, age is an essential factor since there is a ten years difference. Hyperglycaemia in men, overweight in women are major factors as important as tobacco abuse in men, arterial hypertension and dyslipidemia in both sexes. Finally the type A behavior seems to occupy an even larger role in polyarterial patients of both sexes.

[Carcinoid cardiopathy: value of ultrasonography and MRI. Apropos of a case related to bronchial tumor. Review of the literature]. / Cardiopathie carcinoïde: intérêt de l'ultrasonographie et de l'IRM. A propos d'un cas lié à une tumeur bronchique. Revue de la littérature.

A case of carcinoid cardiopathy (C.C.) of the right heart, related to liver metastases secondary to a bronchial tumor, is reported. Non-invasive investigative methods have enabled an easy diagnosis of C.C.: liver metastases by scan and abdominal sonogram, restrictive myocardiopathy with typical tricuspid lesions by echocardiography and MRI, magnitude of the tricuspid regurgitation by cardiac Doppler. These extremely performing methods must allow an early diagnosis at a stage when the patient may be still operable, since C.C. is the most frequent cause of death in patients with carcinoid tumors.

Diaphragmatic origin of false atrial dissociation evidenced through intra-vascular recordings.

In a patient suffering from respiratory insufficiency, an atrial dissociation pattern was found in the surface ECG recording, having the appearance of ectopic P waves, independent from sinus P waves and followed by microfibrillation waves of 450 ms duration. No electrical activity corresponding to the presumed ectopic P waves could be recorded from left and right atria. Conversely, such activity was recorded from the inferior vena cava (IVC) 1.5 cm below its junction with the right atrium, with a maximum amplitude; the occurrence and duration of these recordings appeared to be exactly synchronized with surface ectopic P waves/microfibrillation aspects and the inspiratory phase of respiration. Intravascular recording can be considered as a useful procedure to differentiate false and actual atrial dissociation.

Long-term follow-up of patients treated with VVI pacing and sequential pacing with special reference to VA retrograde conduction.

The aim of this prospective study is comparing long-term prognosis in patients implanted with a VVI pacemaker (group A) with those implanted with a sequential pacing device, AAI or DDD, (group B). Both groups of 45 patients each, were comparable as regards to age, sex, pacing indications, underlying heart disease, and technical conditions of implantation and were followed-up over 55 months. Atrial arrhythmias (A.A.) incidence was higher in group A: 24.4% than group B: 8.8% (P less than 0.05). Arterial embolisms (A.E.) occurred in group A patients only. Worsening or occurrence of exercise limitation was more frequent in group A: 35.6% as compared to group B: 13.3% (P less than 0.05) and deaths related to these complications, occurred in seven cases in group A versus four cases in group B. In group A, all patients who experienced a worsening or occurrence of an A.A. or an A.E., had a ventriculoatrial conduction (VAC). No statistical difference was observed in worsening or occurrence of exercise limitation between patients with VAC and those without VAC: nine (42.8%) and seven (29.2%) but they respectively experienced at least one complication in 16 cases (76.2%) and seven cases (29.2%) (P less than 0.01). In conclusion, long-term prognosis in patients implanted with VVI pacing as compared to patients implanted with sequential pacing is poorer. The presence of VAC in patients treated with permanent VVI pacing is a major factor for complications and deaths related to A.E. and cardiac failure. Thus VVI pacing should be avoided in patients with VAC.

Low-energy cardioversion of spontaneous atrial fibrillation. Immediate and long-term results.

BACKGROUND: Recent studies have suggested that induced atrial fibrillation (AF) could be successfully terminated by using a two-catheter electrode system and low energy (< 400 V). This study evaluated the efficacy and safety of low-energy cardioversion in spontaneous chronic and paroxysmal AF. METHODS AND RESULTS: Forty-two consecutive patients with spontaneous AF underwent low-energy electrical cardioversion. AF was chronic (> or = 1 month) with a mean duration of 9 +/- 19 months in 28 patients (group I) or paroxysmal with a history of recurrent attacks and a mean duration of the present episode of 7 +/- 16 days in 14 patients (group II). An underlying heart disease was present in 28 patients. A 3/3-ms biphasic shock was delivered between catheters positioned in the right atrium and the coronary sinus in 32 patients. In 10 patients, the left pulmonary artery branch was used. The catheters were connected to a custom external defibrillator. The shocks were synchronized to the R wave. Following a test shock of 60 V, the energy was increased in 40-V steps until a maximum of 400 V or restoration of sinus rhythm. Sinus rhythm was restored in 22 of the 28 patients (78%) of group I by using a mean leading-edge voltage of 297 +/- 57 V (mean energy 3.3 +/- 1.3 J) and in 11 of 14 patients (78%) of group II by using a mean leading-edge voltage of 223 +/- 41 V (mean energy, 1.8 +/- 0.7 J). The energy required for terminating chronic AF was significantly (P < .001) higher than that required for terminating paroxysmal AF. Among the other variables studied, the duration of AF significantly affected the successful voltage. Ventricular proarrhythmia occurred in 1 patient with atrial flutter due to an unsynchronized shock. Of the 22 patients of group I in whom sinus rhythm was restored, 14 (63%) remained in sinus rhythm with a mean follow-up of 9 +/- 3 months. Pain level showed a good correlation with increasing voltage. However, a marked inter-individual variation was noted. CONCLUSIONS: Atrial defibrillation using low energy between two intracardiac catheters with an electrical field between the right and left atria and the protocol used is feasible in patients with persistent spontaneous AF. The technique is safe provided synchronization to the R wave is achieved. A low recurrence rate of AF was seen in patients in whom sinus rhythm was restored.

Endless-loop tachycardias: description and first clinical results of a new fully automatic protection algorithm.

Endless-loop tachycardia (ELT) is one of the most common pacemaker mediated tachycardia. An innovative ELT protection algorithm has proven to be clinically effective. A new improved version that will eliminate the need to program any parameter is now under clinical evaluation. Nine patients entered the study: six men and three women, aged 52 +/- 22 years. This automatic algorithm needs only 10 cycles to detect and confirm an ELT. Three hundred thirty-three ELTs lasting more than 9 cycles have been induced and analyzed. The total results are the following: mean duration: 6.7 sec +/- 3.1; mean ELT rate: 137 +/- 21.9 bpm, mean programmed upper rate limit (URL): 142.5 +/- 26.5 bpm (Only 70% of ELTs presented rates equal to programmed URL). (1) ELTs reduced by postventricular atrial refractory period (PVARP) extension on one cycle: 291 ELTs (87%). ELT rate: 128.5 +/- 18.2 bpm. (2) Retrograde block: algorithm operation may induce a retrograde block due to a short atrioventricular delay (AVD) applied during the confirmation phase to discriminate an ELT from a stable sinus rhythm. Thirty-two ELTs (10%) have been reduced and detected on a retrograde block occurrence. (3) Algorithm failure due to an unstable ventriculoatrial conduction time (VACT) even at fixed rate or to a retrograde Wenckebach behavior on AVD reduction during the confirmation phase. A total of 10 algorithms failed to detect or confirm an ELT have been recorded (3%). Mean duration: 8.2 +/- 4.2 sec, mean ELT rate: 148.9 +/- 14.3 bpm. This new fully automatic algorithm has reduced 97% of ELTs, including high rate episodes (100-175 bpm).(ABSTRACT TRUNCATED AT 250 WORDS)