[Cardiac surgery in France (supply, service and needs response): a national survey]. / La chirurgie cardiaque en France (offre, activité et réponse aux besoins): une enquête nationale.

This paper describes the results of a national study of the 70 french cardiac surgery units. This study was required by the ministry of health in order to prepare the planning process of cardiac surgery in France. Results concerning the year 1994 show important regional variations of resources among the country. The number of interventions has increased three fold in 15 years (from 13,000 to 38,000 a year). The share of the different indications are constant (coronaropathy: 53%; valvulopathy: 36%; congenital: 8%). Patient flows across french regions represent 15% of the interventions. Regional intervention rates per capita range from 45 to more than 80 for 100,000 inhabitants. French cardiac surgery is, in fact, organized at a multiregional level and the regional intervention rates are not correlated with mortality or demographic rates.

Multicolor flow cytometry analysis of blood cell subsets in patients given total body irradiation before bone marrow transplantation.

PURPOSE: Bone marrow transplantation has often been closely linked with accidental or intentional therapeutical irradiation. In both situations, study of the radiosensitivity of human blood cell subsets is of interest. Using one-color flow cytometry analysis of B lymphocytes, T cell subsets, and natural killer cells, we previously reported that lymphocyte subsets exhibit equal radiosensitivity. Taking advantage of recent developments in the knowledge of leukocyte differentiation antigens and flow cytometry technology we undertook a study of blood cell subsets to search for rare populations exhibiting different radiosensitivity. METHODS AND MATERIALS: Thirty patients, who were delivered a 12 Gy fractionated total body irradiation as part of their conditioning regimen before transplantation for malignant disorders, were studied using multicolor flow cytometry. RESULTS: T and B lymphocytes showed a sharp, radiation-induced decrease, with the B lymphocytes (cluster of differentiation (CD) 19+) being the most sensitive. When analyzed by multicolor flow cytometry, all major lymphocyte subsets appeared equally sensitive to the in vivo irradiation; that is, CD3+4+45RO+, CD3+4+45RA+, CD3+4+8-, CD3+4-8+. Therefore, all major lymphocyte subsets sharing the helper phenotype (naive or memory) and the cytotoxic phenotype appeared equally sensitive to in vivo whole body irradiation. In parallel, the CD34+ cell subset remained basically unchanged after whole body irradiation. Finally, the CD3-, 56+, 16+ natural killer cell subset was relatively radioresistant (91 and 74% of its initial value, after 2 and 4 Gy, respectively) as compared to other lymphocyte subsets. CONCLUSION: Our study provides evidence that T and B cell subsets seem to be highly radiosensitive in vivo. The CD34+ progenitor/stem cells and NK cells seem to be more radioresistant. This latter result might provide clues to the understanding of the pathophysiogeny of radiation-induced aplasia and of the engrafment/rejection process following bone marrow transplantation.

In vivo induction of apoptosis in human lymphocytes by therapeutic fractionated total body irradiation.

Ionizing radiations have been reported as an in vitro apoptosis initiating stimulus in human lymphocytes. As the cytotoxicity of ionizing radiations and chemotherapeutic agents appears to be dependent on the efficacy of cell death induction, the manipulation of apoptosis initiation might be used as a means to supress some pathological process. In the present study the in vivo induction of gamma-ray mediated programmed cell death in humans is reported. The in vivo induction of apoptosis in peripheral blood lymphocytes (PBL) by ionizing radiations was investigated in 33 patients after each of two sessions (2 Gy and 4 Gy) of fractionated total body irradiation (FTBI) as part of their conditioning regimen before bone marrow transplantation. PBL committed to apoptosis were scored before irradiation (S1), 4 h (S2) and 24 h after 2 Gy (S3, 14-17 h after the second 2 Gy fraction). Nuclear morphology and chromatin-DNA were analysed by fluorescence microscopy immediately after blood sample withdrawal (I) and after 24 h in cell culture medium (II). When scored immediately after withdrawal, no circulating PBL with the apoptotic nuclear morphology were observed in S1 and S2 blood samples whereas S3 disclosed 21.9 +/- 11.7% of circulating lymphocytes with an apoptotic nuclear morphology. After 24 h in culture, S1 samples (before irradiation) generally contained less than 20% of apoptotic lymphocytes. A higher percentage of apoptotic cells was noted in some cases in relation with recent chemotherapy and possibly with pathology. After 24 h in culture, S2 and S3 samples contained 51.7 +/- 17.9% and 60.4 +/- 16.4% of apoptotic lymphocytes, respectively. These results confirm that ionizing radiations induce apoptosis in vivo in human lymphocytes and that the commitment to apoptosis can be determined after low doses (2 Gy) of therapeutic whole body irradiation. The results suggest that susceptibility to apoptosis induction by ionizing radiations could be related to previous therapy by cytotoxic drugs and possibly to the type of haematological malignancy.

Class I and II HLA typing after a 10 Gy-4 hour therapeutic total body irradiation.

Class I and II HLA typing was investigated before and at various intervals after a 10 Gy total body irradiation delivered over 4 h, prior to allogeneic bone marrow graft for various hematological malignancies, in 14 patients. A reliable class I HLA typing appeared to be possible in almost all cases 6-8 hours after the start of irradiation but was only possible in 5 patients after 24 h. Preliminary results with class II antigens might suggest a more marked "fragility" of this antigen class after irradiation. These results encourage the drawing of blood samples for HLA grouping as soon as possible after accidental whole-body irradiation.

Prospective study of the clinical symptoms of therapeutic whole body irradiation.

Thirty-one selected patients with various haematological malignancies who received a 10 Gy-4 h total body irradiation (TBI) at the Institut Gustave Roussy 24 h before high dose cyclophosphamide for bone marrow transplantation, were prospectively evaluated for gastrointestinal symptoms, body temperature, consciousness, headache, xerostomia, parotiditis, ocular symptoms, blood pressure, and respiratory and cutaneous signs for 24 h. In spite of prophylactic administration of various anti-emetic agents, 90% of the patients experienced nausea and 80% experienced vomiting. An almost constant body temperature peak--up to 40.8 degrees C--was registered 6 h after the start of irradiation. No drowsiness was reported since the introduction of the new anti-emetic agent Ondansetron. Nearly half the patients (42%) complained of headache. The proportion of patients experiencing early (during TBI) xerostomia was 61%. 74% of patients complained of parotiditis in the first 24 h. Although this low dose rate whole body irradiation is not likely to be exactly replicated in many accidental human exposures, the incidence rate and the time-course of the observed prodromal phase symptoms may prove helpful for early triage in the case of accidental irradiation.

Clinical basis for TBI fractionation.

Most available clinical data strongly suggest a sparing effect of TBI fractionation for the lungs, liver, lens, the growth cartilage and, perhaps the prepubertal ovary; the usual fractionated TBI regimens, delivering from 12 to 15 Gy, appear to be constantly less toxic than the "standard" 10 Gy single dose TBI scheme. However, there is also some clinical suggestion, essentially coming from the T-depleted graft experience, that the largely used 12 Gy fractionated scheme (6 X 2 Gy) might be less effective than the standard 10 Gy single dose TBI for leukemia cell killing and for eradication of the recipient bone marrow. Additional clinical data, ideally coming from well designed randomised trial or from careful large-scale retrospective evaluations, should help to optimize the TBI delivery.