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J F Obadia

Publications and source records attributed to J F Obadia.

At least 19 recordsLinked to original sources
PubMed2005

[Whipple's disease endocarditis: report of 5 cases and review of the literature].

PURPOSE: Endocarditic lesions (infectious endocarditis) associated with Whipple's disease are exceptional. We report five cases from the cardiovascular and pneumologic hospital Louis Pradel in Lyon. METHOD: We have collected all cases of Tropheryma whipplei endocarditis diagnosed between 1995 and 2004. RESULTS: Five men with a mean age of 53 years at time of diagnosis. The symptoms were essentially cardiovascular: murmur, embolism in 3 cases, and heart failure secondary to valvular insufficiency in 2 cases. The valvular involvement, double in 3 cases, was more often aortic. Vegetations were present in all patients and valvular destruction sometimes very important. A low grade fever was present in 4 cases, associated with weight loss in 2 cases. The only extra-cardiac symptoms were arthralgias or arthritis in all cases, considered in 3 patients as seronegative rheumatoid arthritis, B27+ spondylarthritis, and psoriasic arthritis. Their was no other clinical manifestations of Whipple's disease, particularly digestive, ocular, neurologic or adenopathy, and duodenal biopsies secondarily performed in 4 cases were non contributive. This differs from literature as an extra-cardiac location was identified in 11 out of 17 cases. The diagnosis was obtained by histology and PCR on the cardiac valves, as all the patients underwent surgery. The evolution was favourable with a prolonged antibiotic therapy. CONCLUSIONS: These report confirms the existence of endocarditic forms of the Whipple's disease, in which the single extra-cardiac manifestation is rheumatologic, and reminds us the usefulness of histology and PCR on the cardiac valves at the time of valvular surgery.

Actinobacteria↗
PubMed2004

[Replacement of the ascending aorta with conservation of the aortic valve. Results of 50 cases using the Tirone David procedure].

Aortic valve sparing operations are now widely accepted for ascending aortic aneurysm surgery. We herein report our experience of the Tirone David procedure in larger indications. From January 1997 to August 2003, 50 Tirone David procedure have been performed on 36 male and 14 female (mean age: 60 +/- 15). Five patients presented a Marfan disease and 4 acute dissections. Grade III or IV aortic insufficiency was frequent (40%). Aortic diameter was not particularly dilated, ranging from 44 to 78 mm (mean: 57 +/- 10 mm). Mean ejection fraction: 57 +/- 10%. Mean left ventricular end diastolic diameter =63 +/- 7 mm. An associated mitral valve repair and 1 coronary bypass were necessary. Mean cross clamp and bypass times =94 min and 122 +/- 28 min respectively. There was one in-hospital mortality. Secondary mortality affected 2 patients (non-cardiac deaths), for a cumulative follow-up of 946 months. During follow-up continence control was always excellent, only 1 bicuspid valve had an aortic insufficiency >grade II. Tirone David procedure gave satisfactory results as regards both aortic ectasia and aortic regurgitation control. We consider it feasible even in case of aortic dissection but caution is required when facing bicuspid aortic valves.

Adult↗
PubMed2003

Alteration of the left ventricular contractile reserve in heart transplant patients: a dobutamine stress strain rate imaging study.

BACKGROUND: Strain rate imaging (SRI), a recently developed Doppler-derived process, allows quantification of myocardial systolic function. We investigate whether SRI quantifies the contractile reserve during dobutamine stress tests in heart transplant patients (HT), when compared with normal individuals. METHODS: An incremental dobutamine test (5 to 40 microg/kg per minute) was performed in 10 HT and 15 control subjects, all of whom displayed normal coronary angiography. Gray-scale and color myocardial Doppler data were acquired in standard B-mode views at baseline, low-dose, peak, and recovery. Longitudinal SR was processed from the myocardial velocities for each segment. The changes in maximal systolic SR were used to quantify myocardial contractile reserve. RESULTS: Dobutamine infusion failed to induce clinical symptoms or electrocardiographic (ECG) changes in either group. Visually determined wall motion score was considered normal in all segments for each stage of the dobutamine stress. Heart rate was augmented similarly in both groups during dobutamine infusion. In controls, systolic SR increased gradually with incremental dobutamine dose and returned to baseline values upon recovery. Conversely, in HT patients, the increase in systolic SR was blunted at peak dobutamine, at which point it was significantly different vs controls. CONCLUSIONS: Quantitative assessment of myocardial function using SRI during dobutamine stress revealed an impaired contractile reserve in HT patients with normal coronary angiography. These subtle changes in regional myocardial function could not be identified using visual wall motion scoring. Additional studies are necessary to evaluate whether SR imaging detection of contractile reserve impairment will improve clinical efficiency or event prediction in this population.

Adrenergic beta-Agonists↗
PubMed2001

Acute rejection and cardiac graft vasculopathy in the absence of donor-derived ICAM-1 or P-selectin.

BACKGROUND: ICAM-1 and P-selectin are molecules that facilitate adhesion of circulating leukocytes to vessel walls. We have investigated the role of donor-derived ICAM-1 and P-selectin in acute and chronic cardiac allograft rejection. METHODS: C57BL/6J (H-2(b)) mice were used as donors for heterotopic heart transplantation into CBA/Ca (H-2(k)) recipients. The donors were wild-type or homozygous for gene mutations of ICAM-1 or P-selectin. We measured acute rejection in non-immunosuppressed recipients by daily palpation and sacrificed mice at Days 2, 4, and 6 for immunohistochemical analysis. For chronic rejection, recipients received monoclonal antibody against CD4+ T cells. We removed hearts at Days 60 to 62 for histologic assessment of vasculopathy using quantitative morphometry to measure intimal thickening. RESULTS: Time (days) to rejection was 7.1 +/- 0.57 for wild-type (n = 10), 7.0 +/- 0.71 for ICAM-1 -/- (not significantly different, n = 7) and 6.1 +/- 0.33 (p = 0.001) for P-selectin -/- donors. ICAM-1 deficiency was associated with delayed infiltrate at Day 4 compared with wild-type. In the model of chronic rejection, elastin-positive vessels showed a mean occlusion of 34% +/- 3% in transplanted wild-type hearts; vessels were divided into those showing 0% to 20%, 20% to 50%, and 50% to 100% occlusion. We observed no difference in the number of affected vessels or the amount of vascular thickening in donors lacking ICAM-1 or P-selectin compared with wild-type controls. CONCLUSIONS: The absence of ICAM-1 or P-selectin in donor tissues neither lengthens the time of allograft survival nor inhibits the vascular lesions associated with chronic rejection. Indeed, the absence of P-selectin may exacerbate alloimmune injury.

Animals↗
PubMed2000

Thiopurine S-methyltransferase gene polymorphism is predictive of azathioprine-induced myelosuppression in heart transplant recipients.

Azathioprine (AZA) is metabolized via the cytosolic enzyme thiopurine S-methyltransferase (TPMT). TPMT activity exhibits genetic polymorphism with four prevalent (75%) mutant alleles TPMT*2 (G238C) and TPMT*3 (A719G and/or G460A) and a wild-type allele TPMT*1. To test the hypothesis that presence of these mutations is associated with greater toxicity of AZA in heart transplant recipients, 30 consecutive patients treated with AZA were followed up for the first month after heart transplant. Mutation of TPMT gene (mutation-specific polymerase chain reaction-based methods) was observed in four patients (A719G: n = 2; A719G plus G460: n = 2). Agranulocytosis did not occur in patients with the wild genotype. It occurred in the two patients with mutation A719G and there was a 40% drop in neutrophils in the two other patients. Discontinuation of AZA in the four mutant patients corrected for the drop. Presence of TPMT mutations is associated with a greater likelihood of agranulocytosis. Determination of these mutations could reduce the risk for hematological side-effects.

Adult↗
PubMed2000

Kinetic characterization of CMD-A2-Gd-DOTA as an intravascular contrast agent for myocardial perfusion measurement with MRI.

Recent developments in magnetic resonance imaging (MRI) using specific contrast media allow the assessment of myocardial perfusion. The purpose of this study was to characterize the intravascular properties of a new macromolecular contrast agent, CMD-A2-Gd-DOTA, to evaluate myocardial perfusion. Two groups of isolated pig hearts perfused at various controlled flows were used. To demonstrate the intravascular properties of CMD-A2-Gd-DOTA, the agent was simultaneously injected with 99mTc-labeled red blood cells in five hearts (group 1). Tracer kinetics of both compounds were assessed by coronary sinus effluent sampling, radioactivity counting and concentration determination in samples for first-pass time curves measurements. Five other hearts (group 2) were studied using a two-slice turboFLASH sequence on a 1.5-T whole-body MRI in order to evaluate first-pass CMD-A2-Gd-DOTA signal intensity (SI) versus time curves. In group 1, for the studied flows ranging from 0.8 to 3.1 ml/min(-1) x g(-1), CMD-A2-Gd-DOTA showed first-pass concentration curves typical of an intravascular contrast agent. In group 2, MRI parameters, i.e., upslope and mean transit time of SI time curves correlated strongly with myocardial perfusion. Within the physiologic range of flows, CMD-A2-Gd-DOTA was able to demonstrate tracer kinetics for in vivo assessment of myocardial perfusion using MRI.

Animals↗
PubMed1999

[Ten-year experience with heart transplantation (1987-1997)].

OBJECTIVES: Analyze ten years experience with heart transplantation at the Dijon University Hospital and determine which parameters control mid and long term outcome. PATIENTS AND METHODS: One hundred thirty six heart transplantations were performed over a 10 year period (1987-1997) in 118 men and 18 women aged 51-87 years. Heart transplantation was indicated on the basis of the following criteria: ejection fraction *20%, pulmonary arteriole resistance < 6 Wood units, peak oxygen uptake < 14 l/kg/min. The Shumway or anatomic technique was used. The triple immunosuppressive protocol combined corticosteroids, azathioprine and cyclosporin. The same team conducted the post-transplantation follow-up with regular programmed consultations in addition to those requested by the general practitioner, the cardiologist or the patient. Follow-up was oriented according to the clinical situation (blood chemistry, cell counts, cyclosporinemia, search for infection, echocardiography, endomyocardial biopsy, coronarography). RESULTS: Five patients (3.6%) died when still on the waiting list. Absolute emergency transplantation was performed for patients (28.1%) including 8 (5.9%) after circulatory assist. Hospital mortality was 11.7% and late mortality was 16.1%. Actuarial survival was 78% at 1 year, 71% at 5 years and 69% at 10 years. Among the survivors, 94% were taking two, three or even four drugs for hypertension. Cyclosporin levels decreased and creatinine levels increased. Episodes of rejection were minimal: 86.57% of the biopsies were * grade 1 and 4.45% * grade 2. Cytomegalovirus infection was documented and treated in 7.55% of the cases. Incidence of graft coronary artery disease was 3.4% at 1 year, 6.5% at 2 years and 7.9% at 3 years. CONCLUSION: Our follow-up structure where the same small team conducts regular examinations together with our approach to heart transplantation appears to be the main factor leading to the quality results obtained in this series.

Aged↗
PubMed1999

Influence of temperature on tracheal tube cuff pressure during cardiac surgery.

BACKGROUND: Lateral wall pressure may cause tracheal injury by affecting tracheal capillary blood flow. Damage to the trachea is less severe when lateral wall pressure exerted by the endotracheal tube cuff does not exceed the mean capillary perfusion pressure of the mucosa. The purpose of this study was to determine the effects of hypothermic and normothermic cardiopulmonary bypass (CPB) on tracheal tube cuff pressure dynamics. METHODS: Twenty-two patients were studied during normothermic CPB (pulmonary artery blood temperature in the CPB period between 36 and 35 degrees C), and 22 patients during hypothermic CPB (pulmonary artery temperature in the CPB period between 32 and 28 degrees C). A Mallinckrodt Medical Lo-Contour Murphy tracheal tube, with high-volume, low-pressure cuff was used without lubricant. Intracuff pressure (ITCP) was recorded at end-expiration before, during and after cardiopulmonary bypass. RESULTS: ITCP measurements were different between groups during CPB at aortic cross-clamping (13.9 +/- 0.8 mmHg in the normothermic group versus 11.3 +/- 0.4 mmHg in the hypothermic group, P < 0.05), and respectively during CPB after aortic declamping (15.3 +/- 0.8 mmHg and 12.6 +/- 0.8 mmHg, P < 0.05) and after CPB at the end of surgery (16.8 +/- 0.7 mmHg and 18.6 +/- 0.3 mmHg, P < 0.05). CONCLUSION: We conclude that the ITCP is higher in normothermic CPB than in hypothermic CPB; however, the clinical significance of this observation needs further investigation.

Aged↗
PubMed1999

Thoracoscopic epicardial radiofrequency ablation for vagal atrial fibrillation in dogs.

Epicardial radiofrequency catheter ablation of the atria in the open-chest dog has been shown to reduce inducibility of atrial fibrillation. Video-assisted endoscopic techniques decrease the operative trauma in adult thoracic surgery. We report our results of video-assisted thoracoscopic radiofrequency catheter ablation of the atria for the prevention of atrial fibrillation induction in canines. In 12 consecutive anesthetized dogs, induction of sustained atrial fibrillation was reproducibly obtained by burst pacing and cervical vagal stimulation. In six dogs, biatrial ablation was performed through right and left minithoracotomies and guided by video-assisted endoscopic techniques. The remaining six dogs underwent a video-guided left atrial procedure. Long continuous and transmural lesions were produced using epicardial temperature controlled radiofrequency energy delivery according to a simplified maze approach. Transmural lesions were demonstrated at the end of the study by examination of the heart. Sustained atrial fibrillation was still inducible after the right atrial ablation but sustained atrial fibrillation could not be induced following left atrial ablation. In acute canine studies: (1) epicardial radiofrequency catheter ablation of the atria is feasible using video-assisted endoscopic techniques; (2) ablation extended or confined to the left atrium appears to be effective in preventing the inducibility of sustained vagal atrial fibrillation; and (3) ablation of the right atrium alone had no antiarrhythmic effect.

Animals↗
PubMed1998

[Infections secondary to implantation of cardiac pacemakers].

Infectious complications of pacemaker implantation are not common but may be particularly severe. Localised wound infections at the site of implantation have been reported in 0.5% of cases in the most recent series with an average of about 2%. The incidence of septicaemia and infectious endocarditis is lower, about 0.5% of cases. The operator's experience, the duration of the procedure and repeat procedures are considered to be predisposing factors. The main cause of these infections is though to be local contamination during the implantation. The commonest causal organism is the staphylococcus (75 to 92%), the staphylococcus aureus being the cause of acute infections whereas the staphylococcus epidermis is associated with cases of secondary infection. The usual clinical presentation is infection at the site of the pacemaker but other forms such as abscess, endocarditis, rejection of the implanted material, septic emboli and septic phlebitis have been described. The diagnosis is confirmed by local and systemic biological investigations and by echocardiography (especially transoesophageal echocardiography) in cases of right heart endocarditis. There are two axes of treatment: bactericidal double antibiotherapy and surgical ablation of the infected material either percutaneously or by cardiotomy. Though controversial, and unsupported by scientific evidence, the role of systematic, preoperative, prophylactic antibiotic therapy in the prevention of these complications seems to be increasing.

Abscess↗
PubMed1998

[Reversible graft dysfunction after cardiac transplantation].

The authors report 3 cases of major graft dysfunction after cardiac transplantation which recovered completely with biventricular mechanical assistance in 4 to 8 days. All three cases were primary biventricular graft failures in patients with normal preoperative pulmonary resistances. These early dysfunctions (with no signs of myocardial infarction on electro- or echocardiography and in the absence of abnormal increased peri-operative enzyme levels) associated with total functional recovery conforming to the definition of the phenomenon of myocardial stunning. These results argue in favour of aggressive management of primary graft dysfunction.

Echocardiography, Transesophageal↗
PubMed1997

Mitral subvalvular apparatus: different functions of primary and secondary chordae.

BACKGROUND: The aim of this study was to compare the function of the primary chordae attached to the free edge with that of the secondary chordae attached to the ventricular surface of the anterior mitral leaflet. METHODS AND RESULTS: An isolated working pig heart model was used. Three groups of 7 hearts were compared: Group A was the control group with intact leaflets. In group B, the primary chordae of the anterior leaflet were sectioned and the secondary chordae were left intact before assembly of the working heart model. In group C, the secondary chordae were sectioned and the primary chordae left intact. In group B, atrial and ventricular pressure evidenced dramatic mitral regurgitation. Video monitoring showed significant prolapse of the free edge of the anterior leaflet. Acute mitral regurgitation accounted for the decrease in aortic flow rate to 30 mL/min, significantly lower than in the control group (P=.006). In group C, sectioning of the secondary chordae left a competent mitral valve together with good coaptation of the anterior and posterior leaflets shown by video monitoring. However, aortic flow was lower than in the control group (P=.007), and ultrasonomicrometry evidenced impaired function (P=.009). CONCLUSIONS: This study suggests that the primary and secondary chordae of the mitral subvalvular apparatus have different functions. The primary chordae of the anterior leaflet appeared to be more involved in mitral valve competence, whereas the secondary chordae appeared to be more involved in left ventricular geometry and function.

Animals↗
PubMed1997

Long-term follow-up of small (size 20 and 21) Medtronic-Hall aortic valve prostheses.

BACKGROUND: Our goal was to study the long-term follow-up of patients having aortic valve replacement and to focus particularly on the patients receiving small prostheses. METHODS: Four hundred twenty-eight Medtronic-Hall valves were implanted (156 size 20 or 21 mm, 149 size 22 or 23 mm, and 123 size 25 or 27 mm). Group 20-21 had a higher number of female patients, more associated coronary lesions, and more patients with aortic stenosis. RESULTS: The actuarial survival rate at 8 years was 80% for group 20-21, 80% for group 22-23, and 76% for group 25-27 (p = not significant). In group 20-21, the actuarial event-free rates at 8 years were as follows: thromboembolic complications, 94%; prosthetic valve endocarditis, 99%; reoperation, 98%; and hemorrhagic complications, 78%. The only factors of prognostic value in this group were age and associated coronary lesions. CONCLUSIONS: The durable nature of the results obtained with the Medtronic-Hall 20- and 21-mm prostheses compared with large-diameter prostheses allows the use of a simple and reliable surgical technique and should mean that indications for ring enlargement become rare.

Aortic Valve↗