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Nicolas Bonnet

Publications and source records attributed to Nicolas Bonnet.

23 records · Page 2Linked to original sources
PubMed2005

[Coronary artery bypass graft surgery in patients with diabetes].

UNLABELLED: Diabetes is a potent risk factor for cardiovascular disease. Whatever the treatment, the prognosis of coronary artery disease is poorer in patients with diabetes than in non diabetic patients. Strict equilibration of perioperative glycemia reduces morbidity and mortality associated with coronary artery bypass graft surgery (CABG). PATIENTS AND METHODS: In two hundred consecutive diabetic patients who underwent CABG, perioperative glycemia was equilibrated by using a new aggressive protocol (Group A). In-hospital morbidity and mortality observed in these patients was compared to that observed in 200 diabetic patients who underwent CABG before the protocol was implemented (group B). RESULTS: Preoperative data were similar in the two groups. The mean number of grafts was 2.6 per patient, and the left internal thoracic artery was used in 98% of cases. Use of the two internal mammary arteries increasedfrom 16% in group B to 38% in group A (p < 0.05). However, the rates of wound infection and mediastinitis were similar in the two groups (4%), as was the rate of other complications. In contrast, in-hospital mortality was twice as lower in group A (1.5%) than in group B (3.5%). One-quarter of the patients used insulin, and the rate of infectious complications was higher in this subgroup; however, in-hospital mortality was similar to that among diabetic patients not requiring insulin (2%). Use of the protocol did not affect the outcome of patients requiring insulin. CONCLUSION: Better medical and surgical management of diabetic patients is improving the outcome of CABG surgery, with results now similar to those obtained in non diabetic patients. The use of mammary arteries improves long-term survival. Surgical revascularization remains the most effective treatment for diabetic patients whose coronary artery lesions do not qualify for endovascular revascularization

Aged↗
PubMed2004

Bacterial mediastinitis after heart transplantation: clinical presentation, risk factors and treatment.

BACKGROUND: The incidence of mediastinitis after heart transplantation has been reported to be between 2.5% and 7.5%. Most previous reports from the transplant literature have assessed patients who had not received induction therapy. METHODS: From December 1996 to January 2002, a total of 230 heart transplants were performed using induction therapy with rabbit anti-thymocyte globulin at La Pitié Salpêtrière Hospital (Paris, France). Mediastinitis developed in 15 patients (6.5%). A case-control study was performed to characterize the clinical presentation, microbiology, risk factors and therapy of mediastinitis after heart transplantation. RESULTS: Only 4 patients (26%) had a temperature of >38 degrees C and 6 patients (40%) had a white blood cell count of >10,000 cells/mm(3). Septicemia (46%) and positive temporary epicardial pacing wires culture (60%) were frequently observed. Staphylococcus aureus (5 of 15), Staphylococcus epidermidis (5 of 15) and gram-negative bacteria (5 of 15) were the causative organisms cultured intra-operatively. Mean duration of mechanical ventilation (2.4 vs 1.6 days; p < 0.03) and use of ventricular assistance (20% vs 0%; p < 0.04) were different between cases and controls. The mortality rate at hospital discharge was 6.7% (1 of 15). CONCLUSIONS: In the context of immunosuppression after heart transplantation, a high degree of suspicion is necessary to make the diagnosis of mediastinitis. Positive blood and temporary epicardial pacing wires cultures can be helpful in suggesting the presence of mediastinitis. Using vancomycin and an aminoglycoside as prophylaxis has to be considered because of the high prevalence of methilcilin-resistant S epidermidis and gram-negative bacteria. Conservative therapy (sternal debridement without muscle flap closure, and closed-chest drainage) showed excellent results in this series.

Adult↗
PubMed2003

Influence of mobilized stem cells on myocardial infarct repair in a nonhuman primate model.

Although previous findings have suggested that some adult stem cells are pluripotent and could differentiate in an appropriate microenvironment, the fate conversion of adult stem cells is currently being debated. Here, we studied the ability of mobilized stem cells to repair cardiac tissue injury in a nonhuman primate model of acute myocardial infarction. Mobilization was carried out with stem cell factor, 25 mcg/Kg/d (D), and granulocyte-colony-stimulating factor, 100 mcg/Kg/D administered 5 days before (D - 5 group; n = 3) or 4 hours after (H + 4 group; n = 4) circumflex coronary artery ligation; no growth factor was administered to 3 baboons of the control group. No adverse effect relating to growth factor administration was observed. Flk-1 and transcription factors of cardiac lineages could be detected in peripheral blood only by reverse transcriptase-polymerase chain reaction. When comparing positron emission tomography (PET) with [11C]-acetate between examinations from D2 and D30, a relative increase (perfusion ratio between infarct and noninfarct regions) of 26% (P =.01) in myocardial blood flow was found in the H + 4 group; the relative rate of oxidative metabolism remained unaltered in the 3 groups. No change was observed in the echographic indices of the left ventricular enlargement or systolic function in the 3 animal groups during the 2-month follow-up. The PET findings concurred with the immunohistochemistry analysis of left ventricular myocardial sections with evidence of endothelial cells but no myocyte differentiation; few cycling cells were observed at this time. Thus, the present data suggest that, in nonhuman primates submitted to coronary artery ligation, mobilization by hematopoietic growth factors could promote angiogenesis in the infarcted myocardium, without detectable myocardial repair.

Animals↗
PubMed2003

Circulatory support for fulminant myocarditis: consideration for implantation, weaning and explantation.

OBJECTIVE: Fulminant myocarditis (FM) is an uncommon but life-threatening condition for which a mechanical circulatory support (MCS) device can be life-saving. However, device selection, weaning and explantation procedures remain poorly defined. METHODS: Four patients were bridged to recovery using the Thoratec biventricular support device. All four were in a state of cardiogenic shock with rapid deterioration of their clinical status despite increasing doses of inotropes. Three patients required mechanical respiratory support, three were anuric and one was dialyzed. Echocardiography showed a mean ejection fraction of 12+/-8%. RESULTS: Each Thoratec implantation was performed on cardiopulmonary bypass with a beating heart. Three patients underwent biventricular cannulation. The fourth patient underwent left ventricular and right atrial cannulation. All patients manifested evidence of moderate to severe end organ dysfunction after device implantation. However, by explantation, end organ function had recovered in all patients. After a mean duration of 17+/-10 days, all the patients showed evidence of myocardial recovery. Recovery was confirmed on echocardiography which showed opening of the aortic valve and contraction of both ventricles. The weaning process was performed in 2-5 days by setting the device in a fixed mode and increasing the rate. Device explantation was uneventful in the four patients. At the 6 months echocardiography follow-up, all had normal systolic function. CONCLUSION: In patients with FM, biventricular support allows full circulatory support and unloads both ventricles until recovery occurs. In this set of patients, weaning and removal procedures are straight-forward. These results suggest an aggressive stance toward implantation of MCS in patients with FM.

Adult↗