Influence of decompression sickness on vasomotion of isolated rat vessels.

Several studies have demonstrated that endothelial function is impaired following a dive even without decompression sickness. During this study we determined the effect of decompression sickness on endothelium-dependent and independent vasoreactivity. For this purpose twenty-seven male Sprague-Dawley rats were submitted to a simulated dive up to 1,000 kPa absolute pressure and divided into 3 groups: safe diving without decompression sickness or dives provoking mild or severe sickness. A fourth control group remained at atmospheric pressure. Endothelium-dependent and independent vasomotion was assessed ex vivo by measuring isometric tension in rings of abdominal aorta and mesenteric arteries. Dose-response curves were obtained with phenylephrine, acetylcholine and sodium nitroprusside. Acetylcholine-induced relaxation was measured in the presence of L-NAME, indometacin or both of them at once.Contraction was significantly decreased after each protocol compared with the control rats. Additionally, the response in animals from the severe group was significantly different from that of the safe and mild groups. Dose response curves for acetylcholine alone and in the presence of inhibitors remained unchanged. We did not observe differences in endothelium-dependent vasodilation after diving or in the presence of decompression sickness. Contractile response to phenylephrine was progressively impaired with increased decompression stress. These results may indicate smooth muscle injury.

Joint Position Paper of the Working Group of Pacing and Electrophysiology of the French Society of Cardiology (SFC) and the Société française d'imagerie cardiaque et vasculaire diagnostique et interventionnelle (SFICV) on magnetic resonance imaging in patients with cardiac electronic implantable devices.

Magnetic resonance imaging (MRI) has become the reference imaging for the management of a large number of diseases. The number of MR examinations increases every year, simultaneously with the number of patients receiving a cardiac electronic implantable device (CEID). A CEID was considered an absolute contraindication for MRI for years. The progressive replacement of conventional pacemakers and defibrillators by MR-conditional CEIDs and recent data on the safety of MRI in patients with "MR-nonconditional" CEIDs have progressively increased the demand for MRI in patients with a CEID. However, some risks are associated with MRI in CEID carriers, even with "MR-conditional" devices because these devices are not "MR-safe". A specific programing of the device in "MR-mode" and monitoring patients during MRI remain mandatory for all patients with a CEID. A standardized patient workflow based on an institutional protocol should be established in each institution performing such examinations. This joint position paper of the Working Group of Pacing and Electrophysiology of the French Society of Cardiology and the Société française d'imagerie cardiaque et vasculaire diagnostique et interventionnelle (SFICV) describes the effect and risks associated with MRI in CEID carriers. We propose recommendations for patient workflow and monitoring and CEID programming in MR-conditional, "MR-conditional nonguaranteed" and MR-nonconditional devices.

Effect of exercise training on cutaneous microcirculation in rats.

AIM: Exercise training is known to improve endothelium-dependent relaxation in the coronary and skeletal muscle arteries. However, the effects of exercise training on peripheral nonworking tissue, including microcirculation, are still unclear. Therefore, we investigated the effect of chronic and regular aerobic exercise on cutaneous microvascular endothelial function in rats. METHODS: We assessed the effect of physical training on skin microcirculation in 7 sedentary (SED) and 21 training rats (Wistar-Kyoto), submitted to a treadmill training protocol (15 m/min; 15% incline; 60 min/day; 8 weeks). Training rats were divided into 3 groups, exercising 1 day/week (Ex1), 3 days/week (Ex3) or 5 days/week (Ex5). Cutaneous blood flow was recorded before the beginning of the training protocol, after 4 weeks and at the end of the training program. Hyperemic response (RH) was the flow reaction obtained after sudden release of the garrot. For data analysis, cutaneous vascular conductance (CVC) was indexed as cutaneous blood flow divided by mean arterial blood pressure (in millimeters of mercury, mmHg) and normalized to baseline values. RESULTS: At baseline, CVC was not different among groups (SED or training) at 3 steps of experimental protocol. The hyperemic stimulus significantly increased normalized CVC only in group Ex3 after 4 weeks (P<0.006) and 8 weeks (P<0.006). CONCLUSION: Exercise training exerts a generalized effect on the vasculature by increasing endothelial function in vessel beds different from those perfusing actively working muscle. However, some differences exist since training at a frequency of 3 bouts weekly only modifies cutaneous microcirculation.

[Tolerance and efficacy of early nicotine substitution after acute coronary syndromes]. / Tolérance et efficacité de la substitution nicotinique précoce au décours d'un syndrome coronaire aigu.

The object of this study was to assess the cardiovascular tolerance and efficacy of early nicotine substitution therapy in 100 patients admitted to the Coronary Care Unit for acute coronary syndromes (ACS). The files of the first 100 consecutive patients having received nicotine substitution therapy immediately after an ACS were consulted retrospectively and a questionnaire was sent to all patients. A reply was obtained in 90% of cases. In this series, there was a 7% rate of cardiovascular events in the days following hospital discharge, comparable to previously reported results. The smoking relapse rate at six months after the ACS was 38.9%, a percentage which was less than in previously reported series. Although consultations to help stop smoking and nicotine substitution did not seem to have significant benefits in this study, the authors recommend continuing and improving the management of coronary patients who smoke.

Long-term left ventricular pacing: assessment and comparison with biventricular pacing in patients with severe congestive heart failure.

OBJECTIVE: The purpose of this study is to report prospectively the results of six-month follow-up of permanent left ventricular (LV) based pacing in patients with severe congestive heart failure (CHF) and left bundle branch block (LBBB). BACKGROUND: Left ventricular pacing alone has been demonstrated to result in identical improvement compared to biventricular pacing (BiV) during acute hemodynamic evaluation in patients with advanced CHF and LBBB. However, to our knowledge, the clinical outcome during permanent LV pacing alone versus BiV pacing mode has not been evaluated. METHODS: Pacing configuration (LV or BiV) was selected according to the physician's preference. Patient evaluation was performed at baseline and at six months. RESULTS: Thirty-three patients with advanced CHF and LBBB were included. Baseline characteristics of LV (18 patients) and BiV (15 patients) pacing groups were similar. During the six-month follow-up period, seven patients died three BiV and four LV). In the surviving patients at 6 months, 8 of 14 patients in the LV group and 9 of 12 in the BiV group were in New York Heart Association class I or II (p = 0.39). No significant difference was observed between the two groups in terms of objective parameters except for LV end-diastolic diameter decrease (-4.4 mm in BiV group vs. -0.7 mm in LV group; p = 0.04). CONCLUSION: At six-month follow-up, a trend toward improvement was observed in objective parameters in patients with severe CHF and LBBB following LV-based pacing. The two pacing modes (LV and BiV) were associated with almost equivalent improvement of subjective and objective parameters.

[Medications in smoking cessation]. / Médicaments d'aide au sevrage tabagique.

Physicians can aid their patients' smoking cessation by providing psychological support, advice, behavioral strategies, and drugs. Success depends on appropriate management, including selection of the right moment to begin treatment and an understanding of the development of the withdrawal syndrome, smoking urges, and the possibility of failure. The standard pharmacological treatment for nicotine dependence uses different forms of nicotine substitutes and bupropion, while we await data about other drugs currently under study. The score on the "simplified" Fagerström questionnaire usually determines the initial nicotine dose. Six forms of nicotine substitutes are available. They provide either prolonged nicotine release (transcutaneous patches) that prevents withdrawal symptoms, or rapid release through the buccal and nasal mucosa (chewing gum, suckers, inhalers and nasal sprays) to anticipate the positive effects represented by cigarettes and the urges occurring during withdrawal. The efficacy of these substitutes, widely studied, is approximately twice that of placebo. Their use is no longer contraindicated in patients with heart disease, when necessary. Bupropion should be used in treating nicotine dependence either as a first-line treatment, or if nicotine substitutes (150 mg/d the first week, 300 mg/d thereafter) fail. The combination of bupropion and nicotine substitutes can be considered, either from the outset for heavy or very heavy smokers, or afterwards, if withdrawal symptoms or urges to smoke persist in subjects treated by only one of these two drug classes. One of the new drugs under evaluation is rimonabant, the first representatives of a new class of drugs, selective CB1 endocannabinoid receptor antagonists. Promising results about its use in smoking cessation were released in 2004.

[Echographic diagnosis of systolic murmur among 280 young French militaries. Implications for the expertise in military medicine]. / Diagnostic échographique d'un souffle cardiaque systolique au sein d'une population de 280 jeunes militaires français. Implications en médecine d'expertise militaire.

UNLABELLED: Clinically discovering a systolic murmur is frequent among the young military population. When this murmur does not sound benign, a transthoracic echocardiography (TTE) is made to detect any cardiopathy, which could cause sudden cardiac death. The aim of this study was to evaluate the interest of systematic TTE in the assessment of any cardiac systolic murmur (CSM) among militaries. METHODS: We ran a retrospective monocentric study in the "Clermont-Tonnerre" military hospital in Brest. We included all patients sent for TEE, aged 15 to 30 years old, from the 1st January 2010 until the 31st July 2013. RESULTS: Two hundred and eighty TTES assessing CSM were performed. We found 28/280 (10%) echocardiographic abnormalities: 13 were bicuspid aortic valves (4.6%), 6 were ventricular septal defects (2.15%), 3 were atrial septal defects (1.07%), 4 were mild mitral regurgitations (1.43%), one mild pulmonary stenosis (0.35%) and one aortic stenosis (0.35%). No hypertrophic cardiomyopathy was found. Concerning military expertise, 11 (3.92%) patients among these 28 with abnormal TEE were considered unfit for work or "fit for work with limitations". CONCLUSION: Assessing a cardiac systolic murmur with TEE lead to the diagnosis of a cardiomyopathy in 10% of the case. This study enhances the importance of systematic TEE when a CSM is detected in the young military, in order to determine if those soldiers can still fulfill their military duty.

Prevalence of factor V Leiden in patients with myocardial infarction and normal coronary angiography.

Factor V Leiden is associated with an increased risk of venous thrombosis and myocardial infarction in young women, but not in men in this latter case. The aim of this study was to evaluate the prevalence of this mutation in patients with myocardial infarction but normal coronary angiography. We compared 3 groups of patients: one group consisted of 107 patients with premature myocardial infarction but no significant coronary artery stenosis; another group of 244 patients with myocardial infarction and significant coronary artery stenosis; a third group of 400 healthy controls. Factor V Leiden was found in 13 patients (12.1%) who had a myocardial infarction without significant coronary artery stenosis, 11 patients (4.5%) who had a myocardial infarction with significant coronary artery stenosis (p = 0.01) and in 20 controls (5%) (p = 0.01). Odds ratio associated with factor V Leiden were respectively 2.93 (CI95: 1.18-7.31 ) and 2.63 (CI95: 1.19-5.78) when we compared myocardial infarction patients without significant coronary artery stenosis to controls or to patients with significant coronary artery stenosis. In myocardial infarction patients without significant coronary artery stenosis, prevalence of factor V Leiden is significantly higher than in controls. This new finding supports the hypothesis that thrombosis plays a key role in this selected situation.

Long-term prognosis in patients with alcoholic cardiomyopathy and severe heart failure after total abstinence.

We prospectively evaluated the long-term prognosis of 14 patients with alcoholic cardiomyopathy and severe end-stage congestive heart failure after total abstinence. Improvement was very significant after 6 months of follow-up in most patients, and continued thereafter.

Internal right atrial cardioversion of chronic atrial fibrillation: effects of low-energy biphasic shocks.

This study evaluates the efficacy and safety of internal right atrial cardioversion of atrial fibrillation using a defibrillation right atrial catheter and 2 thoracic patches with low-energy biphasic shocks.

Accuracy and mean duration of different protocols of head-up tilt testing.

Based on the results of our study, > 95% of patients with a positive passive tilt test are also positive during 3 micrograms/min, and especially 5 micrograms/min, isoproterenol tilt test. A proposed time-saving protocol would be to initiate the test with an isoproterenol infusion and to perform a 45-minute passive tilt only in those patients with a positive 5 micrograms/min (an infusion rate reported to have an excessive low specificity) isoproterenol tilt test, and to consider only those with symptoms associated with objective changes during this latter test as "finally positive." An alternative option would be to perform a 45-minute passive tilt only in those patients with a negative 3 micrograms/min isoproterenol tilt test.

Evaluation of left ventricular based pacing in patients with congestive heart failure and atrial fibrillation.

Acute hemodynamic data of left ventricular based pacing were assessed in 2 groups of patients with severe cardiac failure: 11 patients with atrial fibrillation and 17 patients with sinus rhythm. Both biventricular and left ventricular pacing significantly improved acute hemodynamic findings to a similar degree in both groups, suggesting that left ventricular based pacing may be beneficial in patients with severe cardiac failure regardless of whether or not they are in sinus rhythm.

Reimplantation of the right internal thoracic artery as a free graft into the left in situ internal thoracic artery (Y procedure). One-year angiographic results.

Reimplantation of the right internal thoracic artery, as a free graft, into the left in situ internal thoracic artery (Y procedure) has enabled us to bypass more distant marginal vessels, which was not possible by the bilateral technique alone. This prospective study was aimed at evaluating the clinical state of the patients and the degree of patency of grafts within 16 months of follow-up. All 80 patients who underwent the Y procedure between January 1988 and January 1992 were included. This group represented 10% of the 840 patients having coronary bypass during the same period. A total of 202 coronary anastomoses were performed in this series. Early postoperative (30 days) complications included three deaths (3.75%), eight myocardial infarctions (10%), one case of phrenic nerve paralysis (1.25%), two cases of respiratory failure (2.5%), and six wound infections (7.5%). At 3 months' follow-up, 96% of patients were free of symptoms. During the follow-up period, four patients died of noncardiac causes (lung, pancreatic, and brain cancer and rupture of an abdominal aortic aneurysm). At 1 year, 71 patients were free of symptoms (97%). Sixty-one patients underwent coronary angiography between 12 and 24 months. Six patients with peripheral arterial disease were not suitable for coronary angiography, and six refused to be tested. These 12 patients had normal thallium test results in the bypassed area (stress or dipyridamole test). The patency rate of the left internal thoracic artery was 98.3% (n = 60), occlusion rate 1.6% (n = 1), and incidence of threadlike arteries 4.9% (n = 3). Thus the rate of perfect patency was 93.4%. The patency rate of the right internal thoracic artery as a free graft was 93.4% (n = 57), occlusion rate 6.5% (n = 4), and the incidence of threadlike arteries 8% (n = 5). Thus the rate of perfect patency was 85.2%. A total of 169 anastomoses were studied. The rate of patency of the anastomoses to the left anterior descending coronary artery was 96% (n = 58) and the occlusion rate, 4% (n = 2). The patency rate of sequential anastomoses (side to side) to diagonal arteries was 100% (n = 16). Patency rate of anastomoses to obtuse marginal arteries was 95% (n = 58) and the rate of occlusion, 4.9% (n = 3). The patency rate of anastomoses to the posterior descending artery or distal branches of the right coronary artery was 80% (n = 4/5).(ABSTRACT TRUNCATED AT 400 WORDS)

Left ventricular-based pacing in patients with chronic heart failure: comparison of acute hemodynamic benefits according to underlying heart disease.

BACKGROUND: Acute left ventricular-based pacing has been shown to improve hemodynamics in patients with severe heart failure and left bundle branch block (LBBB). However, it is not known whether the cause of the underlying heart disease influences the potential effect of left ventricular-based pacing. OBJECTIVES: The aim of this study was to determine whether beneficial hemodynamic effects of acute left ventricular-based pacing in severe chronic heart failure are dependent on underlying heart disease. METHODS: After coronary angiography, patients with severe heart failure and LBBB were separated into two groups: dilated (25 patients; 20 male) and ischemic cardiomyopathy (21 patients; 20 male). Hemodynamic parameters were evaluated at baseline and during left ventricular-based pacing. RESULTS: Improvement in hemodynamic parameters were similar in both groups, during acute left ventricular pacing (changes expressed in percentage): pulmonary capillary wedge pressure, -16+/-15% vs. -14+/-10%; V wave amplitude, -25+/-18% vs. -21+/-17%; and biventricular pacing, -15+/-15% vs. -11+/-11% and -23+/-18% vs. -16+/-18%, respectively. CONCLUSION: Underlying heart disease does not influence the response to acute left ventricular-based pacing in patients with severe heart failure and LBBB. This finding provides support for including all patients with enlarged heart and heart failure in future studies evaluating left ventricular-based pacing.

Evaluation of left ventricular function and mitral regurgitation during left ventricular-based pacing in patients with heart failure.

BACKGROUND: Beneficial effects of left ventricular (LV)-based pacing on acute hemodynamic parameters were reported in several series, but only a few studies examined the long-term effects of this new pacing procedure. AIMS: To assess long-term effects of permanent LV-based pacing on LV function and mitral regurgitation (MR) in patients with refractory congestive heart failure (CHF). METHODS: A prospective evaluation of LV function and MR was performed in 23 patients with severe but stable CHF and left bundle branch block (mean QRS: 186+/-31 ms) by radionuclide and echocardiographic techniques at baseline and 6 months after implantation of a permanent LV-based (LV alone: 13 patients; biventricular: 10 patients) pacemaker programmed either in a DDD mode (sinus rhythm; n=14) or in a VVIR mode (atrial fibrillation; n=9). RESULTS: Compared to baseline, the 6 months follow-up visit demonstrated a significant increase in radionuclide derived LV ejection fraction from 23.3+/-7 to 26.2+/-7% (P<0.01) and in echocardiographic LV fractional shortening from 13+/-4 to 16+/-6% (P<0.05), without any change in cardiac index, a significant decrease in LV end-diastolic diameter (from 73.2+/-6 to 71.2+/-7 mm; P<0.05), end-systolic diameter (from 63.6+/-6 to 60.2+/-8 mm; P<0.05) and color Doppler MR jet area (from 11.5+/-6 to 6.6+/-4 cm(1); P<0.001). A comparison of patients with LV pacing alone and patients with biventricular pacing showed similar beneficial effects of pacing on MR severity in the two subgroups and a non-significant trend for a better improvement of LV function during biventricular pacing. CONCLUSION: Thus, in patients with severe CHF and left bundle branch block, permanent LV-based pacing may significantly improve LV systolic function and decrease MR.

Surgical angioplasty with exclusion of atheromatous plaques in case of diffuse disease of the left anterior descending artery: 2 years' follow-up.

OBJECTIVE: A new surgical technique of coronary artery angioplasty for diffuse and extensive lesions of the left anterior descending artery (LAD) is evaluated in this study. METHOD: Ninety-four coronary artery reconstructions (CAR) using a new technique of angioplasty of the LAD were performed: mean age of patients was 59+/-8 years, there were 21 patients with unstable angina, and 21 with recent myocardial infarction (MI). SURGICAL TECHNIQUE: Diseased LAD is bypassed with the internal thoracic artery graft (ITA). The anastomosis is made downstream from the significant proximal lesion of the LAD. A long arteriotomy (from 2 to 12 cm) is performed along the LAD up to the healthy arterial wall, followed by coverage with the onlay graft of ITA in such a fashion as to exclude the plaques from the LAD lumen. The wall of the new reconstructed LAD consisted of 75% of ITA and 25% of native LAD. The remaining part of the native LAD forms a posterior gutter giving the origins of septal and diagonal branches. RESULTS: aortic cross-clamping time was 116 min, operative mortality rate was 3.2% (three patients), peri-operative infarction rate 6.6% (six patients). The follow-up was 29 months (SD=10). Of the 91 survivors, two were lost for follow-up and one died of non-cardiac causes. Of the 88 patients clinically evaluated, 81 were free from angina and other cardiac events, two had new myocardial infarction in a non-grafted area, two were in congestive heart failure, and three in angina class II. Sixty patients underwent angiography. There were 57 perfect-patency CAR (95%), two ITA string sign (competitive flow), two ITA occlusions (2.5%) and no re-stenosis. CONCLUSIONS: CAR allows revascularisation of diffusely diseased LAD with acceptable operative mortality and morbidity, 2 years' good clinical results and graft patency. In this series, exclusion of plaques prevented plaque complications.

[Syncope: diagnostic strategy]. / Syncopes: démarche diagnostique.

Syncope is a common symptom of clinical practice which raises the problem of the differential diagnosis of other causes of loss of consciousness and a logical diagnostic strategy to avoid systematic prescription of expensive, invasive and often valueless investigations. The aim of this article is to propose a diagnostic procedure for syncopes in adults based on recent recommendations and the value of currently available diagnostic tests.

[Can atrial fibrillation be managed without anti-arrhythmia drugs?]. / Peut-on se passer des antiarythmiques dans la fibrillation auriculaire?

Antiarrhythmic drugs are widely used in atrial fibrillation. The demonstration of severe pro-arrhythmic effects in recent years has led to the reappraisal of their indications in this pathology. Antiarrhythmic agents have three roles: reduction of the fibrillation, maintenance of sinus rhythm and, in case of failure, control of the ventricular response. In the first indication, although intravenous injection of Class Ic antiarrhythmics is effective in 70% of cases, there is an alternative: electrical cardioversion, which is effective in 90% of cases with the transthoracic method when a certain number of technical conditions are respected. The success rate is even better with endocavitary defibrillation. Sinus rhythm is sustained in only 25% of patients at one year with placebo and in 50% of patients with antiarrhythmic therapy. The alternatives in this indication are few at present and consist in right atrial pacing in cases of vagal fibrillation and biatrial pacing for resynchronizing the activation of the two atriae when there is a major interatrial conduction defect. The control of the ventricular response, in cases of permanent atrial fibrillation, is usually reserved to digitalis, betablockers, amiodarone and some calcium antagonists. They are often inadequate and an alternative is radiofrequency catheter ablation of the atrioventricular node, which requires permanent ventricular pacing. In conclusion, there are a few alternatives to antiarrhythmic drug therapy in atrial fibrillation, but they are relatively ineffective in maintaining sinus rhythm.

[Rupture and extravascular migration of a vena cava filter. Apropos of a case]. / Rupture et migration d'un filtre cave en dehors du vaisseau. A propos d'un cas.

The authors report the case of a 68 year old woman who underwent implantation of a Greenfield vena caval filter for recurrent pulmonary embolism. Migration of the filter out of the vena cava into the perivenal fat was discovered two years later during another embolic episode. One of the spokes of the filter had migrated into the iliac fossa. This case illustrates two possible complications of caval filters: rupture and migration. The increasing number of cases reported in the literature indicates the necessity of keeping a register of the complications encountered with different models to avoid the most dangerous ones.

[Evaluation of beta-adrenergic blockader therapy in vasovagal syncope reproduced by head-up tilt test]. / Evaluation du traitement bêtabloquant dans les syncopes vasovagales reproduites par le test d'inclinaison.

Increased sympathetic tone is one physiopathological mechanism of vasovagal syncope. In this case, betablocker therapy is logical. The reports in the literature suggest that the head-up tilt test can reliably reproduce vasovagal syncope. Ten patients (4 men and 6 women, mean age 59 +/- 18 years) who suffered from recurrent vasovagal syncopes (2 to 10 attacks in 6 patients and more than 10 in the other 4) with a positive initial head-up tilt test (syncope or severe dizziness with marked hypotension after a maximum of 40 minutes at 60 degrees) were treated with atenolol (200 mg daily in 7 cases and 100 mg daily in the other 3). A second head-up tilt test was performed 15 +/- 6 days later under betablocker therapy; this test was negative in 7 and remained positive in 3 cases. Irrespective of the result, the 10 patients followed the same therapy at the same dosage. After 9 +/- 5 months, 3 patients had another syncopal attack; 2 stopped taking their medication and the third patient continued the betablocker because there was a marked reduction in the frequency of his attacks. There were no further syncopal episodes during follow-up of the other 7 patients. The medium-term efficacy could not be predicted from the results of the second head-up tilt test. The following conclusions may be drawn from this study: The head-up tilt test becomes negative in 70% of cases after introducing betablocker therapy, assuming a 100% reproductivity. This treatment is effective in over half the patients at medium term and should be considered in patients with recurrent vasovagal syncope.