[Coronary surgery of the beating heart. First year of experience in a series of 317 non-selected coronary patients]. / Chirurgie coronaire à coeur battant. Première année d'expérience sur une série de 317 patients coronariens non sélectionnés.

From May 1999 to May 2000, 317 unselected patients, representing 92.7% of all coronary artery surgery procedures, underwent open heart surgery of the beating heart by median sternotomy with the aid of a cardiac stabilising device. The main preoperative characteristics were: mean age = 66.1 years; men = 78.9%; left main stem disease = 31.8%; mean left ventricular ejection fraction = 54.1%; mean Parsonnet index = 16.9. These 317 patients were compared with a group of 303 patients who underwent coronary bypass surgery the year before by the same surgical team with cardiopulmonary bypass (CPB) and cardiac standstill. Seven hundred and eighty-six distal anastomoses were carried out in the beating heart group (2.48 grafts per patient) compared with 2.91 in the CPB group: p < 0.001). There were 10.1% single bypass, 37.5% double bypass, 47.3% triple bypass and 5% quadruple bypass procedures. A cardiopulmonary bypass was required in 13 patients (4.1%). The mortality at 30 days was 3.1% versus 4.6% in the CPB group (p = NS). The need for blood transfusion was reduced by nearly 40% in the beating heart group (23.7% versus 39.9%, p < 0.001). The incidence of cerebrovascular complications was reduced from 3% in the CPB group to 0.6% in the beating heart group (p = 0.06). The peak postoperative troponine I levels were much lower in the beating heart group (2.5 versus 6.4 ng/ml, p < 0.001). The authors conclude that surgery on the beating heart is feasible in most patients. Compared with conventional surgery under CPB, there seems to be less requirement for blood transfusion and a tendency to reduce the cerebral risk. Nevertheless, a large prospective randomised trial is required to validate the potential advantages and limitations of this technique with respect to conventional surgery and to determine the optimal indications of surgery on the beating heart.

Analysis of 5S rDNA arrays in Arabidopsis thaliana: physical mapping and chromosome-specific polymorphisms.

A physical map of a pericentromeric region of chromosome 5 containing a 5S rDNA locus and spanning approximately 1000 kb was established using the CIC YAC clones. Three 5S rDNA arrays were resolved in this YAC contig by PFGE analysis and we have mapped different types of sequences between these three blocks. 5S rDNA units from each of these three arrays of chromosome 5, and from chromosomes 3 and 4, were isolated by PCR. A total of 38 new DNA sequences were obtained. Two types of 5S rDNA repeated units exist: the major variant with 0.5-kb repeats and one with short repeats (251 bp) only detected on YAC 11A3 from chromosome 3. Although the 38 sequences displayed noticeable heterogeneity, we were able to group them according to their 5S array origin. The presence of 5S array-specific variants was confirmed with the restriction polymorphism study of all the YACs carrying 5S units.

Structural analysis and physical mapping of a pericentromeric region of chromosome 5 of Arabidopsis thaliana.

The Arabidopsis thaliana CIC YAC 2D2, 510 kb long and containing a small block of 180 bp satellite units was subcloned after EcoR1 digestion in the pBluescript plasmid. One of these clones was mapped genetically in the pericentromeric region of chromosome 5. The analysis of 40 subclones of this YAC showed that they all contain repeated sequences with a high proportion of transposable elements. Three new retrotransposons, two Ty-3 Gypsy-like and one Ty-1 Copia, were identified in addition to two new tandem-repeat families. A physical map of the chromosome 5 pericentromeric region was established using CIC YAC clones, spanning around 1000 kb. This contig extends from the CIC YAC 9F5 and 7A2 positioned on the left arm of chromosome 5 to a 5S rDNA genes block localized by in-situ hybridization in the pericentromeric region. Hybridization of the subclones on the CIC YAC library showed that some of them are restricted to the pericentromeric region of chromosome 5 and represent specific markers of this region.

[Heart surgery in normothermia and aerobiosis: apropos of 530 patients]. / Chirurgie cardiaque en normothermie et aéorobiose: à propos de 530 patients.

Between February and October 1991, 530 consecutive patients underwent myocardial revascularization or valvular surgery with warm continuous antegrade and retrograde cardioplegia (37 degrees C). Three hundred and thirty three patients had isolated myocardial revascularization, 159 valvular surgery alone and 25 had combined valvular and coronary bypass. The global mortality was 5.1%, 3.7% for coronary bypass, 7.5% for valvular surgery and 8% for combined valvular and coronary surgery. A multivariate analysis identified the "reperfusion time" as the only predictive factor of hospital mortality (p < 0.001). Intraortic balloon counterpulsation was required postoperatively in 3.2% of cases, 5.2% of coronary bypass and 0.8% of the valvular patients. Inotropic drugs were used to come off cardiopulmonary bypass in 16.5% of coronary and 37.5% of valvular patients. There were 0.9% perioperative infarctions: 1.2% in the coronary bypass cases and 0.6% in the valvular cases. Spontaneous return to sinus rythm was observed in 87.9% of cases. The average "reperfusion time" was 20.48 +/- 0.7 mn. Analysis of the influence of aortic cross clamp time on cardiac morbidity in two groups of coronary patients (Group I: short cross clamp time less than 60 mn; Group II: long cross clamp time, 60 to 33 mn) showed that the hospital mortality, the prevalence of the use of inotropic drugs and balloon counterpulsation the postoperative cardiac index, the rate of spontaneous de fibrillation and the reperfusion time did not depend on the aortic cross clamp time. Cardiac morbidity.