[Oxygenator thrombosis without heparin resistance in polycythemia vera]. / Thrombose d'oxygénateur en l'absence de résistance à l'héparine mais en présence d'une maladie de Vaquez.

A 55-year-old male with a history of positive HIV serology and polycythemia vera underwent coronary artery bypass graft surgery with normothermic extracorporeal circulation. Following heparin administration the activated clotting time (ACT) was 633 seconds (Hemocron with kaolin). Lower than expected arterial and venous oxygen partial pressures together with high pressure (350 mmHg) in the arterial line upstream of the oxygenator were observed. Because of these signs the oxygenator was changed during the procedure. The outcome was uneventful. Electronic microscopic examination of the oxygenator membrane and thermic exchanger revealed fibrin and platelet deposits. Similar cases are described in the literature during polycythemia vera. Therefore the prevention might be a preoperative treatment with antiplatelet therapy in polycytemia vera.

[Vidéo-assisted mitral valve surgery: state of the art]. / La chirurgie mitrale vidéo-assistée : état de l'art.

Video-assisted mitral valve surgery by right mini-thoracotomy is adopted systematically in many centers in the world. It is a safe procedure that offers good results with low morbidity. His major interest can be appreciated in surgical management of mitral valve regurgitation after coronary artery bypass.

Metachronous single lung transplantation after contralateral pneumonectomy. A ''big'' challenge?

Single lung transplantation for cystic fibrosis is an uncommon therapy. Contralateral pneumonectomy is, in these cases, rarely done before transplantation. Herein, we report the case of a single lung transplantation in a patient who had previously a contralateral pneumonectomy.

[Results of video-assisted mitral surgery in a non-selected population]. / Résultats de la chirurgie mitrale vidéo-assistée dans une population non sélectionnée.

A prospective 'analysis of operative risk and results in video-assisted mitral valve surgery performed in a non selected population is reported. Seventy two consecutive patients (1997-2004) with mean age 60 +/- 12 years underwent a video-assisted mitral valve procedure using a femoral CPB. A transthoracic direct aortic clamping was done in 28 patients (TT) and an endo-aortic occlusion balloon was used in 44 patients (Endo). The surgical approach was a right lateral minithoracotomy in all cases; 16 patients had a previous cardiac surgery. The expected mitral operation (39 repairs, 33 replacements) was done in all cases, without conversion. There were 4 early deaths (1 st month), all in Endo group: 1 aortic dissection, 1 heart failure and 2 sudden deaths. Postoperative complication occurred in 17 patients with 5 reoperations for hemostasis of the thoracic wall. Cumulative rate of mortality and morbidity was 29% in Endo and 28% in TT (ns). Hospital stay was 8 +/- 2 days. At discharge, 4 patients had a residual grade 2 echocardiographic mitral regurgitation after valve repair. In January 2005, with a 1.8 years follow-up, there were 4 late deaths, 3 patients underwent a valve reoperation, 2 patients were still in NYHA class 3 and 5 patients had a residual grade 1 or 2 mitral regurgitation. The 3-year actuarial survival was 86 +/- 10% and the 3-year probability to be free of reoperation was 95 +/- 6%. In mitral valve surgery, video-assisted approach is reliable, the operative risk is controlled and midterm results are not compromised. Video-assisted mitral valve surgery is a new less invasive standard; it is the procedure of choice in valve replacement, in reoperation and in non complex valve repair with good cosmetic results.

Management of an aortic wall ulcer after an aortic dissecting hematoma.

We report the case of a 40-year-old woman who presented with an ulcer of the descending aorta 9 months after ascending aortic surgery for intramural aortic hematoma, which was treated surgically with a supra-coronary aortic replacement. Treatment of the second aortic lesion and the choice between endovascular or surgical approaches are discussed.

[What can be expected from off-pump coronary artery surgery?]. / Que faut-il attendre de la chirurgie coronaire sans circulation extracorporelle?

Coronary artery bypass surgery with beating heart (off-pump) has become more common in the last ten years allowing seven randomized studies with at least 60 patients, comparing off-pump and on-pump coronary bypass. Anaesthesia, monitoring and haemodynamic complications are described. Randomized studies concluded to less elevation of biochemical markers of myocardial and renal injury, less hydric inflation, less cerebral microemboli, reduction of homologous blood transfusions, of hospital stay and global costs. However in low risk patients no reduction in myocardial infarction, atrial fibrillation, stroke, acute renal failure, early reoperation, surgical site infection and mortality were observed. Non-randomized studies suggest a benefit in stroke and mortality in elderly patients but the possibility of incomplete revascularization remains.

[Oxygenator thrombosis without heparin resistance]. / Thrombose d'oxygénateur en l'absence de résistance à l'héparine.

A 55-year-old male with a history of positive HIV serology and Polycytemia vera underwent coronary artery bypass graft surgery with normothermic extracorporeal circulation. Following heparin administration the activated clotting time (ACT) was 633 seconds (Hemocron) with kaolin). Lower than expected arterial and venous oxygen partial pressures together with high pressure (350 mmHg) in the arterial line upstream of the oxygenator were observed. Because of these signs the oxygenator was changed during the procedure. The outcome was uneventful. Electronic microscopic examination of the oxygenator membrane and thermic exchanger revealed fibrin and platelet deposits.

Prospective randomized comparison between redon catheters and chest tubes in drainage after cardiac surgery.

AIM: To compare in a prospective randomized study chest tube (CT) and redon drains (RD) for effectiveness, cost, pain and complications after heart surgery using cardiopulmonary bypass. METHODS: Forty patients undergoing heart surgery were analyzed prospectively. Twenty patients had small RD with strong (-700 mmHg) vacuum and 20 others standard CT. All patients had patient controlled analgesia in the postoperative period and pain was noted. Residual pericardial effusion (RPE) was controlled and quantified at postoperative day 7 with transthoracic echocardiography. Drainage complications were noted and compared in both groups. RESULTS: Surgical statistics were comparable in both groups. Two patients underwent reoperation in CT for clotting, and 1 in RD for active surgical bleeding. One patient had orifice infection in CT. Drainage volumes and times were comparable in both groups at removal (992+/-507 ml in RD, 1154+/-571 ml in CT, p=ns). Morphine consumption and pain estimation were comparable in both groups in the postoperative period and at drainage removal. Echographic control showed important RPE for 3 patients in both groups. System cost was higher in CT compared to RD (up to 7 times). CONCLUSION: RD are comparable to CT in terms of drainage, pain and complications. Nevertheless, they offer better handling and removal conditions and limited cost.

Effect of diaspirin cross-linked haemoglobin (DCLHb) on mean arterial pressure during cardiopulmonary bypass in swine.

Diaspirin cross-linked haemoglobin (DCLHb) is a haemoglobin-based oxygen carrier which had been proposed as a resuscitative solution to replace red cell transfusion in many clinical situations. The present study was designed to evaluate the effect of different volumes of DCLHb 10% (1, 5 and 10 mL kg-1) on the cardiovascular system during cardiopulmonary bypass (CPB), and to determine the effect of DCLHb (18 mL kg-1) when added directly to the CPB prime in anaesthetized swine. DCLHb, when used as a priming solution, induced a significant increase (around 20%) in mean arterial pressure (MAP), which persisted during the entire period of CPB (P < 0.05) as compared with controls. Administration of increasing doses of DCLHb during the time course of CPB resulted in a progressive increase in MAP (P < 0.05), suggesting a linear dose-response relationship. Nicardipine, a calcium channel blocker, returned MAP to baseline. Finally, weaning of CPB was easier in animals that received DCLHb, thereby suggesting a potential protective effect of free haemoglobin in this particular clinical situation.

Lung transplantation by continuous perfusion in an experimental auto-transplant animal model.

OBJECTIVE: The aim of this study was to evaluate the preservation of the lung using the cold flushing technique in association with continuous perfusion of the organ during static hypothermic storage. METHODS: In the first phase, the hearts and lungs of 5 New Zealand rabbits were removed three hours after establishing brain death. The left lungs were each conserved in 200 ml of low-potassium UW solution at 10 degrees C for 3 hours of cold ischemia (control group I). The right lungs were also placed in cold storage but were perfused continuously for three hours with low-potassium UW solution at 10 degrees C (group II). In the second phase, ten rabbits underwent a right lung auto-transplant. Lungs were conserved using two techniques. Histoenzymatic and pathological tests were performed: lung function was evaluated. RESULTS: In the first phase the histopathological examination carried out at the end of storage revealed fewer ischemic alterations in the second group compared to the first. In the second phase a significant hypoxia was observed in group I when both lungs and the right lung only were perfused. The histopathological examination revealed ischaemia/reperfusion lesions in both groups though mainly in group I and a good level of ATPase activity in group II though these results were not significant. CONCLUSIONS: Cold flushing of the pulmonary artery and continuous perfusion during static hypothermic storage appears to guarantee a better partial arterial pressure of oxygen in this model of auto-transplant compared to the classical cold storage method.

A comparative study of Euro-Collins, low potassium University of Wisconsin and cold modified blood solutions in lung preservation in acute autotransplantations in the pig.

OBJECTIVE: The aim of the study was to assess the quality of lung preservation offered by Euro-Collins solution (EC), Cold Modified Blood solution (CMB) and low potassium University of Wisconsin solution (UWLP). METHOD: Fifteen right lung auto-transplantations (five for each solution) in the pig (Large White) were performed after 2 h of cold ischaemic storage in physiological solution at 4 degrees C. Right lung biopsies were performed before ischaemia and 30 min after reperfusion, for histoenzymatic, histopathological and electron microscope studies. RESULTS: After reperfusion, significant alterations were observed in the haemodynamics with only the right lung perfused; pulmonary arteriolar resistance increased by a factor of 5 in the EC group, by a factor of 4 in the CMB group and by a factor of 1.2 in the UWLP group; the right ventricular ejection fraction fell by 60% in the EC group, by 50% in the CMB group and by 31% in the UWLP group. Haemodynamic impairment was lower in the UWLP group (P<0.05; P<0.001) as was ischaemic-reperfusion injury (P<0.05). Oedema was observed in the EC group and extensive alveolar wall damage in the CMB group. Hypoxaemia was observed in all groups but the differences in the degree of hypoxaemia were not significant. CONCLUSIONS: The authors concluded that UWLP solution was the most effective of the three in this transplant model.

Safety of oral nicorandil before coronary artery bypass graft surgery.

Nicorandil is a K(ATP) channel opener used to treat angina. It is cardioprotective and a vasodilator. We conducted a prospective, randomized, double-blind, placebo-controlled study to assess oral nicorandil in patients undergoing coronary artery bypass grafting (CABG) with cardiopulmonary bypass (CPB). Twenty-two patients received nicorandil (10 mg twice a day) and 23 patients received placebo. Haemodynamic data were recorded before induction of anaesthesia (T0), 5 and 20 min after starting mechanical ventilation (T1, T2), before aortic cannulation (T3), after 30 min of CPB (T4), 10 min after CPB (T5) and after 3, 8 and 18 h in the intensive care unit (T6, T7, T8). Serum proteins (creatine kinase metabolite and cardiac troponin I) were measured before and 8 and 18 h after surgery. Haemodynamic values did not differ between the two groups. There was no tachycardia during the study, no significant difference in hypotensive episodes, ST segment changes and no changes in cardiac enzymes. Myocardial infarction after surgery was similar in the two groups. Vasoactive therapy was similar in the two groups. Nicorandil can be continued safely up to premedication without deleterious haemodynamic consequences, but a myocardial protective effect of nicorandil in CABG surgery was not found.

Biphasic response after brain death induction: prominent part of catecholamines release in this phenomenon.

BACKGROUND: The physiopathology of hemodynamic instability that occurs after brain death remains unknown. The aim of this study was to examine the initial response to brain death induction. METHODS: After anesthesia and monitoring, 16 pigs were randomized into a control group (C, n = 8) and a brain death group (BD, n = 8). We inflated a subdural catheter balloon to induce brain death. We analyzed hemodynamic and plasmatic biochemical data for 180 minutes after brain death induction. Energetic compounds were measured. We expressed the results in comparison with the C group. RESULTS: The C group remained stable. One minute after brain death, the Cushing reflex appeared, with a hyperdynamic response to plasma catecholamines levels increasing (norepinephrine and epinephrine, 3.1-fold, p = 0. 02, and 3.8-fold, p = 0.07, respectively). After a return to baseline, we recorded a second hyperdynamic profile 120 minutes later. At this time, a second peak of catecholamines appeared (6. 3-fold, p = 0.04, and 9.1-fold, p = 0.02, concerning norepinephrine and epinephrine). At the same time, we observed brief myocardial lactate production (+175%, p < 0.01), with a rise of troponine I (+64%, p = 0.03). The energetic index was similar in both groups: 0. 85 (+/-0.02) in the C group vs 0.87 (+/-0.02) in the BD group. CONCLUSIONS: In this model, biphasic plasmatic catecholamine release appears to primarily explain the physiopathology of the hemodynamic response to brain death induction.

[Minimally invasive cardiac surgery: surgical techniques and anesthetic problems]. / Chirurgie cardiaque mini-invasive: techniques chirurgicales et particularités anesthésiques.

OBJECTIVE: To review current data on minimally invasive cardiac surgery. DATA SOURCES: Search through the Medline data base of French or English articles. DATA EXTRACTION: The articles were analysed to make a synthesis of the various techniques with their main indications and contra-indications. DATA SYNTHESIS: Minimally invasive cardiac surgery includes various surgical procedures. The usual techniques are described, their major benefits and drawbacks are discussed. The main goals of anaesthetic management are preservation of ventricular function and systemic perfusion, detection and treatment of myocardial ischaemia, prevention of hypothermia in case of coronary artery bypass grafting on the beating heart via sternotomy, intermittent selective ventilation of the collapsed lung using CPAP in case of limited thoracotomy. Expertise in transoesophageal echocardiography is essential for insertion and checking the accurate positioning of the various catheters of the endovascular CPB Heartport system (pulmonary vent, endosinus catheter, venous cannula, endoaortic clamp) allowing coronary artery bypass grafting and mitral valve surgery through limited thoracotomy and finally, detection of retained intracardiac air and assessment of complete clearing of cardiac cavities after mitral valve surgery through limited thoracotomy and aortic valve surgery via ministernotomy. Short-acting anaesthetic agents allow rapid recovery from anaesthesia, early extubation and discharge to the surgical ward within 24 h, whereas overall time spent in the operating room is often longer than with conventional cardiac surgery.

Two-year assessment by exercise thallium scintigraphy of myocardial revascularization using bilateral internal mammary and gastroepiploic arteries.

OBJECTIVE: To assess the blood flow supply offered to the myocardium by surgical revascularization using bilateral internal mammary (IMAs) and gastroepiploic (GEA) arteries. METHODS: Two-year assessment by exercise thallium myocardial scintigraphy without medical treatment was performed in 122 patients (mean age 61 +/- 9 years) who underwent coronary artery bypass grafting (CABG) with exclusive use of IMAs and GEA. Usually, the right IMA was used to bypass the left anterior descending coronary artery, and the left IMA to bypass the diagonal and the marginal arteries as a sequential graft if required. The GEA was used to bypass the right coronary artery (RCA) in 50 patients and its posterior branches in 72 patients. RESULTS: During maximal or submaximal exercise stress testing, 119 patients (98%) were asymptomatic and 26 patients (21%) exhibited moderate ischemic ECG modifications which were correlated (P < 0.01) with incomplete revascularization and with the use of GEA to bypass the RCA. A third of patients had moderate ischemic thallium defects on exercise reversible after redistribution (anterior, 10; lateral, 2; inferior, 28). Silent residual myocardial ischemia detected by thallium scintigraphy was correlated (P < 0.001) with ECG modifications and incomplete revascularization; and inferior thallium defects were more frequent when GEA bypassed the RCA (P < 0.05). However, 26% of patients had residual ischemia despite a complete revascularization, and in at least 18% of cases for GEA and 8% for right IMA, arterial graft blood flow was insufficient at maximum exercise level and caused silent residual myocardial ischemia detected by thallium scintigraphy. CONCLUSIONS: Myocardial revascularization using bilateral IMAs and GEA offers a satisfactory myocardial perfusion in the majority of cases; however silent residual myocardial ischemia was detected in a third of patients and was related to incomplete revascularization and to insufficient blood flow supply probably due to small diameter of the arterial grafts.

Severe morbidity after coronary artery surgery: development and validation of a simple predictive clinical score.

AIMS: To develop a predictive clinical risk score of post-operative morbidity after coronary artery bypass grafting. METHODS AND RESULTS: Data were collected retrospectively from 679 patients undergoing emergency or planned bypass surgery between 1 January and 31 December 1996. The incidence of morbidity was 23%. Multivariate stepwise logistic regression analysis on two-thirds of the patients identified eight independent risk factors for severe morbidity. Six of these were pre-operative: symptomatic right heart failure, previous ventricular arrhythmias, previous coronary bypass surgery, chronic pulmonary disease, ST changes on pre-operative electrocardiogram, body mass index <24 kg. m-2, and two were intra-operative factors: the surgeon who operated, and the cardiopulmonary bypass time. A predictive clinical risk score was developed with the six pre-operative risk factors. The negative predictive value of the model is 87% and the area under the receiver operating characteristic curve is 0.77. When tested on the remaining patients not used for developing the model, the area under the curve is 0.65. CONCLUSION: This pre-operative risk score provides a simple method of risk stratification for patients undergoing coronary artery surgery. However, as for all predictive models, the performance of the score decreases when applied to a population other than that used to develop it.

Does the extended use of arterial grafts compromise the myocardial recovery after coronary artery bypass grafting in left ventricular dysfunction?

OBJECTIVE: To assess the prognostic factors of myocardial recovery expected after coronary bypass surgery and the impact of surgical technique used, a prospective non-randomized study including a 1-year postoperative evaluation of left ventricular function was performed in patients with left ventricular dysfunction (left ventricular ejection fraction (LVEF) < 0.40). METHODS: From 1993 to 1996, 110 patients (mean age 61+/-11 years) were included in the study. The mean LVEF was 31+/-6%. All patients had preoperative radionuclide investigations based on the combination of stress/reinjection thallium single photon emission computed tomography (SPECT) and planar evaluation of LVEF; 88% of patients had reversible ischemic thallium defects. Two surgical technique were used: 53 patients received the left internal mammary artery with associated sequential vein graft, and 57 patients received only arterial grafts, internal mammary and gastroepiploic arteries. The mean number of distal anastomoses was 3.2+/-0.8 and 54% of patients had complete revascularization. At 1 year, all survivors had clinical evaluation and the same radionuclide investigations. RESULTS: The early mortality was 2.7%. At 1 year, 100 patients were surviving; on average, NYHA class decreased 1.9+/-0.8 to 1.4+/-0.6 (P < 0.01) and CCS class from 2.8+/-0.6 to 1+/-0.3 (P < 0.01). The mean LVEF increase from 31+/-9 to 34+/-10% (P < 0.01) and the mean LV end-diastolic volume decreased from 317+/-112 to 285+/-108 ml (n.s.). The postoperative improvement in LV function was higher in patients in NYHA class 3 or 4 before surgery (P < 0.05), when associated sequential vein graft had been used (P < 0.01), and in patients with low preoperative LVEF (P < 0.01). The postoperative LVEF improvement observed was significantly correlated with the improvement in left ventricular end-diastolic (LVED) volume and the improvement in redistribution/reinjection thallium uptake. Multivariate analysis showed that the surgical technique used and the preoperative LVEF were independent prognostic factors of the postoperative myocardial function recovery, with a significant positive impact of the vein use. CONCLUSION: This study confirms the excellent clinical results of coronary artery bypass grafting (CABG) in patients with coronary artery disease and LV dysfunction; improvement in LV function can be documented objectively and is correlated with reperfusion of hibernating myocardium. However, the extended use of arterial grafts does not allow to achieve the significant myocardial recovery observed with the use of one internal mammary artery (IMA) and associated sequential vein graft; it seems to be related to the preoperative selection of patients, but a direct negative impact of arterial grafts was documented and leads to be cautious in patients with severe LV dysfunction.

[Long-term outcome of mitral valve repair of dystrophic mitral regurgitation]. / Evaluation à long terme de la chirurgie réparatrice dans l'insuffisance mitrale dystrophique.

Between January 1984 and December 1994, 130 patients underwent mitral valvuloplasty for pure dystrophic mitral regurgitation. There were 94 men and 36 women with a mean age of 61 +/- 9 years: 52 patients were in atrial fibrillation; 91% of patients were in NYHA Classes III or IV. At preoperative echocardiography, the regurgitation was assessed as Grade III or IV and classified using the Carpentier classification according to type I (dilatation of the annulus) or II (mitral valve prolapse); 95% of patients had isolated prolapse of the posterior leaflet, 3% had isolated prolapse of the anterior leaflet and 2% had prolapse of the two leaflets. After valvuloplasty, a prosthetic ring was implanted in 124 patients (95%). The early mortality was 3%; 5.3% of patients had early complications. All patients underwent control transthoracic echocardiography in the first postoperative week. They were reviewed with a second transthoracic echocardiography after a mean follow-up of 5 +/- 0.3 years and a cumulative follow-up of 657 years-patients. At the immediate postoperative echocardiography, 24 minimal residual regurgitations were observed; at long-term, 20 new mitral regurgitations developed, all mild without any clinical symptoms and 98% of patients were in the NYHA Classes I or II. At 10 years, the actuarial survival was 73 +/- 16%; absence of thromboembolic complications 95 +/- 3%, absence of reoperation 95 +/- 5%. This study confirms the efficacy of mitral valvuloplasty and the postoperative stability of repaired valvular lesions. These results suggest that the operative indications should be considered at an earlier stage.