Experimental design approach for deposition optimization of RF sputtered chalcogenide thin films devoted to environmental optical sensors.

The development of the optical bio-chemical sensing technology is an extremely important scientific and technological issue for diagnosis and monitoring of diseases, control of industrial processes, environmental detection of air and water pollutants. Owing to their distinctive features, chalcogenide amorphous thin films represent a keystone in the manufacture of middle infrared integrated optical devices for a sensitive detection of biological or environmental variations. Since the chalcogenide thin films characteristics, i.e. stoichiometric conformity, structure, roughness or optical properties can be affected by the growth process, the choice and control of the deposition method is crucial. An approach based on the experimental design is undoubtedly a way to be explored allowing fast optimization of chalcogenide film deposition by means of radio frequency sputtering process. Argon (Ar) pressure, working power and deposition time were selected as potentially the most influential factors among all possible. The experimental design analysis confirms the great influence of the Ar pressure on studied responses: chemical composition, refractive index in near-IR (1.55 µm) and middle infrared (6.3 and 7.7 µm), band-gap energy, deposition rate and surface roughness. Depending on the intended application and therefore desired thin film characteristics, mappings of the experimental design meaningfully help to select suitable deposition parameters.

Pulsed laser deposited GeTe-rich GeTe-Sb2Te3 thin films.

Pulsed laser deposition technique was used for the fabrication of Ge-Te rich GeTe-Sb2Te3 (Ge6Sb2Te9, Ge8Sb2Te11, Ge10Sb2Te13, and Ge12Sb2Te15) amorphous thin films. To evaluate the influence of GeTe content in the deposited films on physico-chemical properties of the GST materials, scanning electron microscopy with energy-dispersive X-ray analysis, X-ray diffraction and reflectometry, atomic force microscopy, Raman scattering spectroscopy, optical reflectivity, and sheet resistance temperature dependences as well as variable angle spectroscopic ellipsometry measurements were used to characterize as-deposited (amorphous) and annealed (crystalline) layers. Upon crystallization, optical functions and electrical resistance of the films change drastically, leading to large optical and electrical contrast between amorphous and crystalline phases. Large changes of optical/electrical properties are accompanied by the variations of thickness, density, and roughness of the films due to crystallization. Reflectivity contrast as high as ~0.21 at 405 nm was calculated for Ge8Sb2Te11, Ge10Sb2Te13, and Ge12Sb2Te15 layers.

Extracorporeal circulation as an additional method for cerebral protection in simultaneous carotid endarterectomy and coronary artery surgical revascularization.

Surgical management of patients with concomitant carotid and coronary artery stenosis remains controversial. Our policy was always to perform at the same time carotid endarterectomy (CE) and coronary artery bypass grafting (CABG), but it was also considered that extracorporeal circulation (ECC), because of full heparinization, hemodilution, pulsatile flow, and hypothermia could provide better cerebral protection during CE. Retrospective data of 124 patients undergoing simultaneous CE and CABGs between January 1994 and December 2001 were reviewed. CE was performed prior to ECC in 65 patients (Group 1-mean age: 70.4 years; sex ratio: 49 male/16 female) and under ECC, prior to CABGs in 59 patients (Group 2-mean age: 69.9 years; sex ratio: 46 male/13 female). Overall hospital mortality was 7.3% (9/124): cardiac-related in 5 patients, or due to septicemia (1 patient), or ARD syndrome (1 patient), or stroke in two others. Univariate analysis demonstrated overweight, unstable angina, and emergency to be significant risk factors. Bilateral carotid stenosis was a significant risk factor of neurologic event when CE was performed prior to ECC (p < 0.05). In Group 1, mortality was 9.2% (6/65), and the incidence of neurologic events was 10.7% (7/65), and was responsible for two of the early deaths in patients with bilateral carotid stenosis. In Group 2, mortality was 5.1% (3/59) but never related to CE, while the neurologic morbidity was 1.7% (1 transient ischemic attack). It is concluded that (1) hospital mortality in patients undergoing simultaneous CE and CABGs was mainly cardiac-related. (2) The combined approach of both localizations appears to be mandatory, when carotid stenosis, even asymptomatic, was hemodynamically significant, or with ulcerative lesions likely to be responsible for embolism. (3) CE, first performed under ECC, appears to be a safe procedure, combining, in terms of cerebral protection, the benefits previously called up. This approach is all the more interesting when carotid stenosis is bilateral; hypothermia < or = 28 degrees C during the carotid clamping time is obviously the optimal method for cerebral protection when ipsilateral or contralateral supply is reduced, or even absent.

Surgery of chronic traumatic aneurysm of the aortic isthmus: benefit of direct suture.

OBJECTIVE: Retrospective evaluation of long term results after direct suture repair of chronic traumatic aneurysm of the aortic isthmus. METHODS: From March 1979 to June 1998, a total of 19 patients with chronic traumatic aneurysm of the aortic isthmus were operated on, among whom 12 (63%) underwent direct suture. These 12 patients (age ranging from 19 to 68 years; mean 34.2 years) constitute the subject of this study. All but one suffered traffic accidents. Mean delay between trauma and surgery was 4 years (range 3 months to 12 years). All patients underwent a left posterolateral thoracotomy through the fourth intercostal space. Extracorporeal circulation for spinal cord protection was installed in six patients (five ilio-iliac shunts, one atrio-iliac shunt). Aortic rupture was partial in five and circumferential in seven patients. The mean clamping time was 25 min. The absence of loss of aortic substance and a careful mobilization of the aorta made the repair by direct suture easier; this technique could thus be achieved in 63.2% of all 19 patients operated on of chronic traumatic aneurysm within the same period. RESULTS: There was no in-hospital death and no postoperative paraplegia. With a median follow-up of 15 years 3 months (ranging from 22 to 10 years), there were no late complications. Chest X-ray was normal in all patients; eight of them underwent a control angiography between 18 and 72 postoperative months; all these angiographies but one (20% stenosis without gradient) demonstrated a normal appearance of aortic isthmus. CONCLUSION: Direct suture for repair of chronic traumatic thoracic aneurysm is a safe procedure: long-term outcome was excellent and the complications observed with prosthetic grafts or with aortic endoprosthetic stent-grafts were avoided.

Surgical repair of an aneurysm of the innominate artery with fistulization into the trachea.

This report describes a 43-year-old patient presenting with an aneurysm located at the junction between the innominate artery and aorta, with spontaneous fistulization into the trachea. Emergency treatment of this unusually located lesion was undertaken to prevent intratracheal rupture. After ligation of the innominate artery, right common carotid artery, and right subclavian artery due to the risk of infection, the tracheal fistula was treated by direct closure and exclusion using an autologous pericardial flap. The procedure was performed under extracorporeal circulation and circulatory arrest with profound hypothermia.

The short- and mid-term results of bidirectional cavopulmonary shunt with additional source of pulmonary blood flow as definitive palliation for the functional single ventricular heart.

OBJECTIVE: The purpose of this study was to demonstrate the early and late outcomes of bidirectional cavopulmonary shunt (BCPS) as a definitive procedure for the functional single ventricular heart. METHOD: From September 1991 to December 1997, 34 patients underwent a BCPS procedure without a routine conversion to Fontan circulation. The additional source of pulmonary blood flow was left in all patients. Conversion was performed only when it was required for excessive cyanosis. RESULTS: The hospital mortality rate was 8.8% (3/34, 95% confidence limit; 1.9-23%) and the 5-year survival rate was 75% for a mean follow-up period of 33+/-22 months. Seven patients underwent a conversion procedure for remnant or recurrent cyanosis and deterioration of exercise tolerance. Four of these patients died after conversion to Fontan circulation. Twenty-five long-term survivors with BCPSs maintained an arterial oxygen saturation of 84+/-6.1%, and 52% of them had a normal exercise tolerance or mild limitation. No patients developed severe late complications other than recurrent cyanosis. CONCLUSION: Due to the high mortality after conversion to Fontan circulation in patients whose conditions had deteriorated, we could not demonstrate the clear superiority of long-term BCPS over the construction of Fontan circulation for management of the functional single ventricular heart. If deteriorated conditions were successfully managed in the late period, the outcome of long-term BCPS would have been better.

Does EuroSCORE work in individual European countries?

OBJECTIVE: Because of national epidemiological differences in adult heart surgery in Europe, the effectiveness and desirability of a pan-European score for the assessment of quality of surgical care remains controversial. We assessed the predictive value of EuroSCORE in national subsets of the EuroSCORE database. METHODS: The EuroSCORE development data set was divided into national subsets of which those with 500 or more patients were selected for analysis. The Hosmer-Lemeshow goodness-of-fit test was applied to assess the calibration of the EuroSCORE model on individual national samples and the areas under the receiver operating characteristic (ROC) curve were measured to analyse the EuroSCORE discriminative power on individual death prediction. RESULTS: There were 18676 patients in the six largest national samples: Germany, United Kingdom, Spain, Finland, France and Italy (mean: 3113 patients; range: Finland 1266 to France 4507). Major differences were observed in national distribution of procedures: coronary artery bypass grafting accounted for 77.7% of procedures in Finland but only 46.2% in Spain. The EuroSCORE model goodness-of-fit was satisfactory in all countries (P-value overall: 0.4; UK: 0.34; Finland: 0.87; no values less than 0.05). Areas under ROC curves were 0.81 in Germany, 0.79 in the UK, 0.74 in Spain, 0.87 in Finland, 0.82 in France and 0.82 in Italy. CONCLUSION: Despite epidemiological differences between European countries, the discriminative power of EuroSCORE was good in Spain and excellent in all other countries. The system, developed from a merged European database, can therefore be used to assess improvement in quality of care achieved by surgeons and institutions as well as for international European comparison in adult heart surgery.

Early and long-term (one-year) effects of the association of aspirin and oral anticoagulant on thrombi and morbidity after replacement of the mitral valve with the St. Jude medical prosthesis: a clinical and transesophageal echocardiographic study.

OBJECTIVES: The aim of the study was to test the value of low dose aspirin associated with standard oral anticoagulants (OAC) after mechanical mitral valve replacement (MMRV) to reduce strands, thrombi and thromboembolic events. BACKGROUND: Strands and thrombi are thought to increase the risk of embolic events after MMVR, particularly in the immediate postoperative period. METHODS: Two hundred twenty-nine patients were prospectively recruited: 109 patients (group A+) were randomly assigned to aspirin (200 mg per day) with OAC and 120 patients (group A-) to OAC alone (international normalized ratio 2.5 to 3.5). All patients were subjected to multiplane transesophageal echocardiography at nine days and five months and were followed up for one year. RESULTS: At nine days and five months, there was a high and comparable incidence of strands in the two groups (group A+: 44%, 58%; group A-: 49%, 63%). However, the incidence of nonobstructive periprosthetic valve thrombi was significantly lower in group A+ at 9 days: 5% versus 13%, p = 0.03. Total thromboembolic events were reduced in group A+ (9% vs. 25%, p = 0.004) although there was an increased incidence of gastrointestinal hemorrhage (7% vs. 0%). Overall mortality was 9% in group A+ and 4% in group A-. Valve-related events were similar in both groups. Early thrombi, but not strands, were associated with higher morbidity, especially thromboembolic events (30% vs. 13%, p = 0.003). CONCLUSIONS: One year after MMVR, the association of aspirin with OAC reduced thrombi and thromboembolic events, but not morbidity, due to an increase in hemorrhagic complications.

Risk factors and outcome in European cardiac surgery: analysis of the EuroSCORE multinational database of 19030 patients.

OBJECTIVE: To assess risk factors for mortality in cardiac surgical adult patients as part of a study to develop a European System for Cardiac Operative Risk Evaluation (EuroSCORE). METHODS: From September to November 1995, information on risk factors and mortality was collected for 19030 consecutive adult patients undergoing cardiac surgery under cardiopulmonary bypass in 128 surgical centres in eight European states. Data were collected for 68 preoperative and 29 operative risk factors proven or believed to influence hospital mortality. The relationship between risk factors and outcome was assessed by univariate and logistic regression analysis. RESULTS: Mean age (+/- standard deviation) was 62.5+/-10.7 (range 17-94 years) and 28% were female. Mean body mass index was 26.3+/-3.9. The incidence of common risk factors was as follows: hypertension 43.6%, diabetes 16.7%, extracardiac arteriopathy 2.9%, chronic renal failure 3.5%, chronic pulmonary disease 3.9%, previous cardiac surgery 7.3% and impaired left ventricular function 31.4%. Isolated coronary surgery accounted for 63.6% of all procedures, and 29.8% of patients had valve operations. Overall hospital mortality was 4.8%. Coronary surgery mortality was 3.4% In the absence of any identifiable risk factors, mortality was 0.4% for coronary surgery, 1% for mitral valve surgery, 1.1% for aortic valve surgery and 0% for atrial septal defect repair. The following risk factors were associated with increased mortality: age (P = 0.001), female gender (P = 0.001), serum creatinine (P = 0.001), extracardiac arteriopathy (P = 0.001), chronic airway disease (P = 0.006), severe neurological dysfunction (P = 0.001), previous cardiac surgery (P = 0.001), recent myocardial infarction (P = 0.001), left ventricular ejection fraction (P = 0.001), chronic congestive cardiac failure (P = 0.001), pulmonary hypertension (P = 0.001), active endocarditis (P = 0.001), unstable angina (P = 0.001), procedure urgency (P = 0.001), critical preoperative condition (P = 0.001) ventricular septal rupture (P = 0.002), noncoronary surgery (P = 0.001), thoracic aortic surgery (P = 0.001). CONCLUSION: A number of risk factors contribute to cardiac surgical mortality in Europe. This information can be used to develop a risk stratification system for the prediction of hospital mortality and the assessment of quality of care.

Early and long term results of coronary artery bypass grafts in patients with dialysis dependent renal failure.

OBJECTIVE: Coronary artery disease is the main cause of mortality and morbidity in patients on renal therapy replacement. The aim of this study was to define peri-operative risk and long term results of coronary artery bypass grafts (CABG) in dialysis patients. METHODS: this retrospective study included 82 patients in chronic dialysis who underwent CABG between 1978 and 1997. The mean age was 61+/-10 years (range 28-81 years), 84% of the patients were male and the average duration of dialysis was 57 months (range 1-148 months). Combined procedures were carotid endarterectomy in one case, left ventricular aneurysm resection in one and valvular replacement in 10 (nine aortic and one mitral replacements). The operation was elective in 42 patients (51 %) and urgent in the others. Previous myocardial infarction was found in 37 patients (45%) and left ventricular ejection fraction (LVEF) at less than 45% in 15 patients (18%); 23 patients (28%) were in NYHA class III or IV and regarding angina functional status, 77% in CCS class 3 or 4. Follow-up was complete. Statistical analysis included 30 and pre and peri-operative data. Statistical analysis used Chi-square analysis or Fisher's exact test, and the Mann-Whitney test when appropriate. The estimated probability of survival, including postoperative mortality, was calculated by the method of Kaplan-Meyer, and the Log-Rank test used to compare the results. RESULTS: the hospital mortality was 14.6 % (n = 12). Ischemic time and ECC time were significantly lengthened in dead patients (P = 0.01). Moreover, use of internal mammary artery was directly related to lower hospital mortality (P = 0.02). For previous myocardial infarction, LVEF at less than 45%, diabetes and combined procedure, a P-value of < or = 0.1 was calculated. The follow-up ranged from 1 to 140 months (mean 36 months). There were 39 late deaths. The survival rates (included hospital mortality) were 71+/-5%, 56+/-6% and 39+/-6% at 1, 3 and 5 years, respectively. All surviving patients improved their functional status and had symptomatic relief. Statistical analysis showed significant difference in favor of long term survival for patients younger than 60 years, LVEF > 45% and NYHA class I or II. CONCLUSION: these data confirm that CABG in patients with renal replacement therapy is associated with an high operative and long term mortality. However it allows an improvement of functional status, and so, let possible duration of dialysis. It may be expected that more active prevention and detection of coronary disease might improve these results.

Moderately hypothermic cardiopulmonary bypass and selective cerebral perfusion in ascending aorta and aortic arch surgery. Preliminary experience in twenty-two patients.

Deep hypothermic cardiocirculatory arrest is the commonest method of brain protection during transverse aortic arch surgery. Its principle drawbacks consist in the limited safe ischemic period and in the coagulative, renal and pulmonary complications related to low body temperatures and prolonged cardiopulmonary bypass time. Different selective cerebral perfusion techniques have recently raised the interest of some surgical teams in an effort to obviate these problems. The authors' initial experiences with 22 patients, ranging in age from 19 to 78 years (mean, 55 +/- 15 years), who underwent ascending aorta and/or aortic arch replacement using selective cerebral perfusion and moderately hypothermic cardiopulmonary bypass are reported here. Acute aortic dissection and atherosclerotic aneurysm were the commonest lesions observed: ascending aorta associated with partial or complete arch replacement was the most widely performed procedure. With regard to the perfusion technique, after regular cardiopulmonary bypass had been established through the iliac vessels, selective cerebral perfusion was started after aortic arch vessels cannulation (innominate artery, bilateral common carotid artery, innominate artery and left common carotid artery, or right common carotid artery) using a single roller pump separately from the systemic circulation, and brain perfusion was achieved by blood cooled at 30 degrees C, at a flow rate that ranged from 300 ml/min to 1500 ml/min, at a perfusion pressure of approximately 65 mmHg, with the patient maintained at moderate hypothermia (30 degrees C rectal). To perform distal aortic repair, if transverse aortic arch or proximal descending aorta cross-clamping was not feasible, cardiopulmonary bypass flow was lowered to 300-350 ml/min and an open anastomosis was performed, while independently assuring cerebral perfusion (six patients). There were three hospital deaths (mortality rate of 13.6%; s.d. 6.0-25.5%; 70% confidence limit), but none because of cerebral accident. No paraplegia occurred. One patient suffered from right hemiparesis, neither renal nor pulmonary complications were observed. Two chest reexplorations were necessary for bleeding, which were partially related to hemocoagulative disorders. In our experience, the technique of moderately hypothermic cardiopulmonary bypass and selective cerebral perfusion in aortic surgery has provided good results with regard to cerebral protection and organ function preservation. Therefore, allowing a prolonged distal aortic reconstruction period, it may be considered as a safe alternative to profound hypothermia associated with cardiocirculatory arrest in aortic arch surgery.

Predictive factors of maximal aerobic capacity after cardiac transplantation.

Exercise capacity in cardiac transplanted patients has been reported to remain decreased in some studies; however, functional results after transplantation may vary, ranging from modest to spectacular improvement. The aim of the study was to quantify exercise capacity in a large series of transplanted patients and to search for factor predictive of a good functional result. Eighty-five patients (mean 52.1 +/- 11.8 years) underwent exercise testing with respiratory gas exchange measurements 1 to 100 months after transplantation. Mean performance was 112.4 +/- 33 W with a peak VO2 of 21.1 +/- 6 ml.min-1.kg-1. Heart rate was 103 +/- 14 at rest, reaching 142 +/- 22 beats.min-1 at the end of exercising. In univariate analysis, maximal or submaximal aerobic capacity parameters were strongly correlated with chronotropic reserve (r = 0.63; P < 0.001) without correlation with cold ischaemic time, number of rejection episodes or right bundle branch block. In multiple regression analysis, chronotropic reserve, time from transplantation, age of donor and age of patient were proved to be the variables best correlated with peak VO2. Our study confirms the persistence of a large decrease in aerobic functional capacity despite cardiac transplantation; limited exercise capacity does not improve over time, and is limited not only by the patient's age but by that of the donor, and especially by chronotropic reserve.

[Alteration of myocardial viability and systemic ventricular dysfunction after Senning procedure]. / Altération de la viabilité myocardique et dysfonction ventriculaire systémique après intervention de Senning.

After a Senning procedure for transposition of the great arteries (TGA), systolic dysfunction of the right ventricle (RV) is common. Pre and peroperative chronicale hypoxia may be the cause of this ventricular myocardial alteration. In order to detect abnormalities of myocardial viability and to study their relationship to RV function, the authors studied 41 patients (pts), 11.3 +/- 3 years after a Senning procedure. All patients underwent myocardial scintigraphy of the RV under basal conditions. 1 hour after injection of 1.5 mCi of Thallium 201. The RV ejection fraction (n = 41) and at peak effort (n = 25). Exercise ability and aerobic capacity were assessed by exercise testing (Bruce) with gas exchange measurement and compared with 41 normal matched subjects. The cardiorespiratory response to exercise was altered in the Senning group : duration of effort (10.5 +/- 2 vs 13.2 +/- 2 min; p < 0.0001), peak VO2 (33 +/- 5 vs 44.4 +/- 6 ml/min/kg; p < 0.0001), anaerobic threshold (6 +/- 1 vs 8.4 +/- 1.9 min; p < 0.05) were lower compared to controls. Abnormalities of RV viability were observed in 18/41 pts (44%), moderate in 12 cases and severe in 6 cases. Resting and exercise RVEF were significantly lower in patients with myocardial defects (45 +/- 5 vs 51 +/- 7%; p < 0.0005, and 49 +/- 9 vs 58 +/- 9%; p < 0.05 respectively). In conclusion, after the Senning procedure for TGA, scintigraphic abnormalities of the systemic ventricule are common and associated with an alteration of systolic function at rest and on exercise.

Is the Parsonnet's score a good predictive score of mortality in adult cardiac surgery: assessment by a French multicentre study.

OBJECTIVE: Parsonnet proposed a preoperative score ("initial Parsonnet's score", which predicts the hospital mortality of adult cardiac surgery. This score was then modified by including several risk factors used in the 'SUMMIT' system ("modified Parsonnet's score", 44 variables). We wanted to assess the predictive value of these two scores in a French surgical population. METHODS: From December 1992 to April 1993, in France, we organised a prospective multicentre study on adult cardiac surgery mortality and morbidity. Data on 6649 patients were included. We analysed statistically the predictive value of each risk factor and of the two scores on mortality and morbidity at one month. RESULTS: Only 6 of the 15 variables of the initial Parsonnet's score and 19 of the 44 variables of the modified Parsonnet's score significantly influence hospital mortality. Both scores are able to predict hospital mortality and severe morbidity, but the modified Parsonnet's score has the best predictive value (initial Parsonnet's score: odds ratio by point of score = 1.01, area under the roc curve = 0.64; modified Parsonnet's score: odds ratio by point of score = 1.05, area under the roc curve = 0.70). CONCLUSIONS: This study shows that the Parsonnet's scores are predictive, but that these scores remain imperfect: many risk factors are non significant, the initial Parsonnet's score has a moderate predictive value, and the modified Parsonnet's score is too complex (44 variables). Thus, we have built a new score for cardiac surgery in French adults.

Cardiorespiratory response to exercise after venous switch operation for transposition of the great arteries.

STUDY OBJECTIVES: This study reports on the cardiorespiratory response to graded exercise in patients after venous switch operation for transposition of the great arteries. DESIGN: Several small studies have documented a diminished exercise tolerance after Mustard repair for transposition of the great arteries, little information exists, however, about long-term cardiorespiratory exercise performance in patients who have had the Senning procedure. PATIENTS: This prospective study reports on the serial long-term (mean, 11 +/- 2.8 years) cardiopulmonary exercise performance of 43 patients (age, 12 +/- 3.1 years) who underwent a Senning procedure, with no significant postoperative abnormalities. Forty-three matched healthy children were also studied as a control group. MEASUREMENTS AND RESULTS: All underwent exercise testing (Bruce protocol) with metabolic gas exchange to determine parameters at 3 min, anaerobic threshold, similar heart rate (150 beats/min), and peak exercise. Time of exercise was 10.5 +/- 1.9 min in patients and 13.4 +/- 2 min in control subjects (p = 0.0001). Overall, patients reached 73% of peak oxygen uptake achieved by control subjects (32.6 +/- 5.6 vs 44.7 +/- 6 mL/kg/min). Chronotropic response (188 +/- 15.7 vs 166.5 +/- 19.6 beats/min [p = 0.0001]) and oxygen pulse (7.4 +/- 2.9 vs 10.7 +/- 4.2 mL/beat [p = 0.0002]) were lower in patients at peak exercise. Patients had a greater respiratory response to exercise: both respiratory rate and ventilatory equivalent for carbon dioxide were significantly higher at all stages of exercise. Exercise capacity assessed by peak oxygen uptake was correlated with time elapsed since surgical repair (r = 0.48; p = 0.001). CONCLUSIONS: It is concluded that even in asymptomatic patients, exercise endurance and respiratory response are generally altered as much as 11 +/- 2.8 years after venous switch operation, although early surgical repair is predictive of a better long-term functional result.

Intermediate-term results after en bloc double-lung transplantation with bronchial arterial revascularization. Bordeaux Lung and Heart-Lung Transplant Group.

OBJECTIVE: Between May 1990 and January 1994, 18 patients underwent en bloc double-lung transplantation with tracheal anastomosis and bronchial arterial revascularization. Because at that time it was already suggested that chronic ischemia could be a contributing factor in occurrence of obliterative bronchiolitis, the purpose of this study was to evaluate, with a follow-up ranging from 22 to 69 months, the midterm effects of bronchial arterial revascularization on development of obliterative bronchiolitis. RESULTS: Results were assessed according to tracheal healing, functional results, rejection, infection, and incidence of obliterative bronchiolitis. There were no intraoperative deaths or reexplorations for bleeding related to bronchial arterial revascularization, but there were three hospital deaths and five late deaths, two of them related to obliterative bronchiolitis. According to the criteria previously defined, tracheal healing was assessed as grade I, IIa, or IIb in 17 patients and grade IIIa in only one patient. Early angiography (postoperative days 20 to 40) demonstrated a patent graft in 11 of the 14 patients in whom follow-up information was obtained. Ten patients are currently alive with a 43-month mean follow-up. Among the 15 patients surviving more than 1 year, functional results have been excellent except in five in whom obliterative bronchiolitis has developed and who had an early or late graft thrombosis. Furthermore, those patients had a significantly higher incidence of late acute rejection (p < 0.02), cytomegalovirus disease (p < 0.006), and bronchitis episodes (p < 0.0008) than patients free from obliterative bronchiolitis. CONCLUSION: We conclude that besides its immediate beneficial effect on tracheal healing, long-lasting revascularization was, at least in this small series, associated with an absence of obliterative bronchiolitis, thus suggesting but not yet proving the possible role of chronic ischemia in this multifactorial disease.

[Cerebral protection by selective cerebral perfusion during surgery on the aortic arch]. / Protection cérébrale par perfusion cérébrale sélective dans la chirurgie de la crosse aortique.

The aim of this study was to evaluate the technique of cerebral protection by selective cerebral perfusion with moderate hypothermia during surgery of the transverse aortic arch. Twenty-three patients were operated for partial or total replacement of the transverse aortic arch between January 1987 and December 1993 by the technique of selective cerebral perfusion by bilateral carotid cannulation. There were 12 cases of aneurysm of the ascending aorta and/or transverse aortic arch, one aneurysm of the innominate artery and 10 Stanford type A aortic dissections. The selective cerebral flow rate was 1-1.5 l/min; the perfusion pressure 60-80 mmHg and the temperature of cerebral perfusion 25-28 degrees C. The perioperative mortality was 13%; the causes of death were not neurological (3 haemorrhages). The neurological morbidity was 10% (one brachial monoparesis and one bulbar tetraparesis). This is therefore a useful technique of cerebral protection which avoids the complications of deep hypothermia with circulatory arrest and does not limit the time of aortic repair.

Review of the long-term course of 52 patients with pulmonary atresia and ventricular septal defect. Anatomical and surgical considerations.

This study reviews the long-term course of 52 patients with pulmonary atresia and ventricular septal defect seen in a single institution and followed for a mean period of 8.6 years (range 2 days to 20 years). Before the first operation, pulmonary blood supply was provided by ductus arteriosus supplying confluent pulmonary arteries in 26 patients (50%, group I), and was partially or entirely dependent on systemic collateral arteries in the other 26 patients (group II). The angiographic mean ratio of diameters of the right and left pulmonary artery/descending aorta (McGoon ratio) was significantly lower in group II than in group I, 0.76 +/- 0.42 vs 1.04 +/- 0.17 (P = 0.006). Severe arborization defects (with fewer than 10 pulmonary vascular segments connected to central pulmonary arteries) were present only in group II patients (eight patients: 15%), six of whom had congenital absence of the central pulmonary arteries. Corrective surgery was performed in 23 patients (44%, 14 in group I, nine in group II). All but one, who died later, had a McGoon ratio > or = 1 (mean 1.19 +/- 0.18) at time of repair. There was one hospital death (4%) and two late deaths (9%). All but one of the surviving corrected patients were in functional class I or II. Conduit replacement reoperation was performed in three patients (14%), 6, 10 and 13 years, respectively, after repair. At the end of the study, among the 37 patients (71%) who were alive (17 in group I, 20 in group II), 20 (39%) were corrected (12 in group I, eight in group II), four await corrective surgery, and six (11.5%) are estimated inoperable (all in group II) because of very hypoplastic or absent pulmonary arteries. This study confirms the estimated rate in the published literature of long-term survival in patients with pulmonary atresia and ventricular septal defect, and the good results of corrective surgery whenever the size and distribution of pulmonary arteries are satisfactory. The problem of very hypoplastic pulmonary arteries and severe arborization defects remains contentious.