[About an implantable cardioverter-fibrillator]. / Fibrillateur automatique implantable.

A 61-year-old man has been implanted with a Ventritex Profile MD V-186 HV3 ICD for ischemic cardiomyopathy with sustained inducible VT. Three years later, this patient received several inappropriate shocks during the device's interrogation. These shocks provoked ventricular fibrillation. They were caused by a failing soldering between the system random accessory memory (SRAM) module and the hybrid circuit of the device. The device was explanted in emergency.

[Reversible cardiogenic shock under 5-fluorouracil treatment]. / Réversibilité d'un etat de choc cardiogénique sous 5-fluorouracil.

5-fluorouracil, an antimetabolite agent, has been widely used since 1957 for treatment of varied types of cancer such as gastro-intestinal, pancreas, breast, lung, head and neck malignancies. Cardiotoxicity of 5-fluorouracil is rare and was first described in 1975. It can induce severe complications and involve vital prognosis in the short-term. These complications are less known by cardiologists than medical oncologists. The following clinical case represents a potentially serious and rare case of completely reversible cardiogenic shock in a patient with a colo-rectal cancer. A better knowledge of these complications could reduce cases of death by an earlier diagnosis, and a better evaluation of patients with high cardiotoxicity risk.

Circulating procoagulant microparticles and soluble GPV in myocardial infarction treated by primary percutaneous transluminal coronary angioplasty. A possible role for GPIIb-IIIa antagonists.

Circulating procoagulant microparticles (MP) were measured as markers of vascular damage and prothrombotic risk in patients undergoing ST-segment myocardial infarction (STEMI) treated by primary percutaneous transluminal coronary angioplasty (PTCA) and additional GPIIb-IIIa antagonists. Cells possibly more responsive to GPIIb-IIIa (alpha(IIb)beta(3)) antagonists were evidenced through MP phenotypes by comparison with healthy volunteers (HV) and STEMI patients treated by PTCA without GPIIb-IIIa antagonist (CP). In 50 STEMI patients, blood samples were collected at day 1 and day 6. Circulating procoagulant MP were captured on annexin V and quantified by prothrombinase assay as nanomolar phosphatidylserine equivalents (nm PhtdSer). Platelet activation by thrombin was confirmed through independent measurement of soluble GPV (sGPV). With respect to HV, procoagulant MP levels were high in patients with STEMI or unstable angina, platelet-derived MP and elevated sGPV testifying to significant platelet activation. A substantial release of endothelial-derived MP was evidenced simultaneously. In abciximab-treated patients, procoagulant MP, mainly of platelet origin, decreased precociously at day 1 (4.2 +/- 0.6 vs. CP 15.5 +/- 2.1 nm PhtdSer; P = 0.001) together with sGPV (36 +/- 3 vs. CP 58 +/- 8 ng mL(-1); P = 0.02). Leukocyte-derived MP decreased at day 6 (0.12 +/- 0.04 vs. CP 0.56 +/- 0.12 nm PhtdSer; P = 0.01) suggesting a possible effect on underlying inflammatory status. In patients presenting cardiovascular events at 6-month follow-up, procoagulant MP levels at day 1 could be indicative of a worsened outcome. MP could constitute a relevant parameter for the follow-up of STEMI patients treated by GPIIb-IIIa antagonists.

Protective effects of vitamin C on endothelium damage and platelet activation during myocardial infarction in patients with sustained generation of circulating microparticles.

During myocardial infarction (MI), high levels of circulating procoagulant microparticles (MP) shed from endothelial cells and platelets diffuse prothrombotic and proinflammatory potentials crucial for the coronary prognosis. In addition to conventional treatments, we evaluated whether vitamin C treatment could modify circulating levels of procoagulant MP. Upon admission, 61 patients with MI were prospectively randomized for immediate additional vitamin C treatment. Circulating MP were quantified by functional prothrombinase assay before and after 5 days of vitamin C administration (1 g day-1). The cellular origin of MP was also assessed. In vitamin C-treated patients, the reduction in platelet-derived MP was 10% higher (P = 0.01). In patients with diabetes mellitus, dyslipidemia or more than two cardiovascular risk factors, vitamin C decreased endothelial and platelet-derived MP levels by approximately 70% and 13%, respectively. This early effect on circulating platelet and endothelial-derived MP, testifies to the importance of oxidative stress during MI. Vitamin C could prove beneficial for the outcome of patients at higher thrombotic risk.

Ablation of serotonin 5-HT(2B) receptors in mice leads to abnormal cardiac structure and function.

BACKGROUND: Identification of factors regulating myocardial structure and function is important to understand the pathogenesis of heart disease. Because little is known about the molecular mechanism of cardiac functions triggered by serotonin, the link between downstream signaling circuitry of its receptors and the heart physiology is of widespread interest. None of the serotonin receptor (5-HT(1A), 5-HT(1B), or 5-HT(2C)) disruptions in mice have resulted in cardiovascular defects. In this study, we examined 5-HT(2B) receptor-mutant mice to assess the putative role of serotonin in heart structure and function. METHODS AND RESULTS: We have generated G(q)-coupled 5-HT(2B) receptor-null mice by homologous recombination. Surviving 5-HT(2B) receptor-mutant mice exhibit cardiomyopathy with a loss of ventricular mass due to a reduction in number and size of cardiomyocytes. This phenotype is intrinsic to cardiac myocytes. 5-HT(2B) receptor-mutant ventricles exhibit dilation and abnormal organization of contractile elements, including Z-stripe enlargement and N-cadherin downregulation. Echocardiography and ECG both confirm the presence of left ventricular dilatation and decreased systolic function in the adult 5-HT(2B) receptor-mutant mice. CONCLUSIONS: Mutation of 5-HT(2B) receptor leads to a cardiomyopathy without hypertrophy and a disruption of intercalated disks. 5-HT(2B) receptor is required for cytoskeleton assembly to membrane structures by its regulation of N-cadherin expression. These results constitute, for the first time, strong genetic evidence that serotonin, via the 5-HT(2B) receptor, regulates cardiac structure and function.

[Value of the analysis of pulmonary venous flow in the evaluation of hemodynamics in dialysed patients]. / De l'intérêt de l'analyse du flux veineux pulmonaire dans l'estimation d'un état hémodynamique. Exemple de la dialyse.

The aim of this study was to assess the value of analysis of pulmonary venous flow in the evaluation of the haemodynamic status of patients with chronic renal failure with normal left ventricular function, treated by haemodialysis. Pulmonary venous flow was recorded immediately before and after haemodialysis in 27 patients with chronic renal failure and a mean age of 44 years. Three groups of patients were defined according to the change in mitral E/A ratio: Group I (E/A < 1 before and after dialysis), Group II (E/A > 1 before and < 1 after dialysis) and Group III (E/A > 1 before and after dialysis). There was a significant difference between these subgroups before dialysis with respect to age, S, D, VTI S, Total VTI, VTI S/Total (p < 0.05). However, because the values overlapped, only a VTI S/Total ratio greater than 59% differentiated patients in Group II from those in group III (p < 0.05). After dialysis, the change in S/D and VTI S/Total ratios increased in Groups I and II and decreased in Group III. The authors concluded that 63% of patients without LV dysfunction on haemodialysis have abnormalities of relaxation which are latent in 47% of cases due to increased filling pressures diagnosed by a VTI S/Total ratio > 59% or simply because the patients are over 50 year old.

[Paradoxal lowering of parasympathetic indices in myasthenic patients]. / Diminution paradoxale des paramètres parasympathiques chez les patients myasthéniques.

Myasthenia gravis is an autoimmune disease presenting antibodies developed against the nicotinic receptors of acetylcholine. The aim of this study was to evaluate heart rate variability in these patients. Heart rate variability was studied with 24 hour Holter recordings. Eighteen myasthenic patients, 7 men and 11 women, under pyridostigmine treatment, with an average age of 40 years (25 to 63 years) were aged and gender matched to a control group of 18 healthy subjects. All patients exhibited normal cardiac status and Doppler echocardiography. The following parameters were collected over 24 hours and the data further differentiated between night and day: for the temporal domain: heart rate, SDNN, pNN50, rMSSD; and for the spectral domain: total power, high frequency (HF) and low frequency (LF) power. The mean heart rate was slightly higher in the myasthenic group (non significant), due to a less marked nocturnal bradycardia. There was a decrease in the observed absolute values of SDNN as well as temporal and spectral parasympathetic indices (pNN50, rMSSD, HF) (p < 0.01) over the 24 hour period. The results were more significant during the night. Cardiac parasympathetic modulation is significantly modified in myasthenic patients. Considering that lack of bradycardia argues against an over active vagal tone, three hypothesis are discussed that favor of a low vagal tone: antibodies effects on the nicotinic receptors of the autonomic nervous system, respiratory impairment and a desensitization of the acetylcholine receptors.

Optimizing the hemodynamic performance of the DDD pacemaker: impact of the atrioventricular delay on the pulmonary venous flow pattern.

UNLABELLED: This study evaluated the impact of the atrioventricular delay (AVD) on the pulmonary venous flow pattern (PVFP). METHODS: Transthoracic Doppler PVFP were obtained during atrial and ventricular pacing at a fixed rate of 70 beats/min in 20 patients equipped with a DDD pacemaker, diastolic dysfunction linked to an impaired relaxation, a mean ejection fraction of 49%, and AV block. Two subgroups were analyzed equally: group I: seven patients with a normal ejection fraction and group II: 13 patients with decreased ejection fraction. Three different AVDs were studied: short (50 ms), intermediate (150 ms), and long (250 ms). RESULTS: As the AVD increased, the diastolic filling time and the peak atrial reverse flow wave decreased (P < 0.001). There was a decreasing D wave and no significant change in the peak velocity of the S wave. The S wave became biphasic in all patients at the longest AVD of 250 ms. The systolic (S) velocity time integral (VTI) of the pulmonary wave and the systolic/total PVF-VTI ratio increased significantly (P < 0.001). A similar response was seen in both group of patients. CONCLUSIONS: These data correlated the AVD with PVFP, supplying critical systolic information completing the diastolic data obtained from mitral Doppler patterns. These systolic measurements were especially useful for patients with heart failure and a DDD pacemaker, in order to obtain the longest diastolic filling time at the lowest atrial pressure.

[Variability of heart rate after heart surgery under extracorporeal circulation: aortocoronary bypass or aortic valve replacement]. / Evolution de la variabilité de la fréquence cardiaque après chirurgie cardiaque sous circulation extra-corporelle: pontages aorto-coronariens ou remplacements valvulaires aortiques.

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 arrhythmia after pneumonectomy. Apropos of 100 cases and review of the literature]. / Troubles du rythme supraventriculaire après pneumonectomie. A propos de 100 cas et d'une revue de la littérature.

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.

[Doppler echocardiography of left ventricular filling in chronic renal insufficiency: before and after dialysis]. / Etude écho-Doppler du remplissage ventriculaire gauche chez l'insuffisant rénal chronique: avant et après dialyse.

Hemodialysis can achieve loss of body water, variable in the different water compartments, and that depends on the dry weight and the composition of the dialysate. We have studied echocardio-Doppler findings in 26 end stage renal disease patients (from 26 to 84 years), in whom 25 have hypertension, in sinusal rythm and ejection fraction above 55%. When they achieved a 3.52% decrease in body weight, without modification of heart rate and decrease in median arterial pression, these patients exhibited decrease in auricular (p = 0.001) and ventricular diameter both in systole and diastole (p = 0.001), in maximum velocity of E wave (p = 0.001) and E/A ratio. There was no significant reduction of maximum velocity of A wave, but 4 differents patterns of E/A ratio were demonstrated. The main determinant factor of these patterns was found to be the age of the patient.

[Diastolic dysfunction in chronic renal failure patients under hemodialysis]. / Dysfonction diastolique chez l'insuffisant rénal chronique en hémodialyse.

Myocardial hypertrophy due to volume and pressure overload is common in hemodialysis patients because renal failure is usually responsible for arterial hypertension. The left ventricular filling pattern often exhibits abnormalities denoting a relaxation disorder. These abnormalities increase after hemodialysis sessions, which are sometimes followed by severe hypotension. This sequence of left ventricular hypertrophy, altered relaxation, and severe postdialysis hypotension sometimes associated with severe ventricular rhythm disorders deserves to be studied in detail. The data gathered would help to determine the prognosis in this situation, which often depends on cardiac function.

[Aneurysm of the interatrial septum. Apropos of a retrospective study of 41 cases]. / Anévrysme du septum interauriculaire. A partir d'une série rétrospective de 41 cas.

The authors undertook a retrospective study of 41 patients in whom an atrial septal aneurysm (ASA) had been diagnosed at transoesophageal echocardiography performed for ischaemic cerebrovascular events in 26 cases. No significant differences in this size, thickness or mobility of the ASA or the associated cardiac abnormalities were demonstrated in this context. However, patients presenting with cerebrovascular accidents were older, had several cardiovascular risk factors and more cardiac arrhythmias. These arrhythmias were usually related to other cardiac pathology such as ventricular hypertrophy or chronic cor pulmonale. Moreover, the probability of the cerebrovascular accident being related to the ASA was only acknowledged in 11 cases. These results mean a certain degree of discretion in diagnostic investigation and therapeutic management of these cases.

A case of recurrent benign pericarditis treated by colchicine.

After five recurrences of idiopathic pericarditis over a period of 8 months on steroidal anti-inflammatory therapy, a splenectomized patient aged 31 years benefited from treatment with colchicine. He was treated for one year without any recurrence. A relapse occurred 6, 7 and 17 months after having stopped the drug. This observation raises the question whether colchicine might be beneficial in recurrent benign pericarditis with or without corticodependence and have a prophylactic action against recurrences.