Restenosis or rapid progression in non-dilated sites are not predictors of late spontaneous coronary events.

The present study was designed to assess the prognostic value of clinical and angiographic factors, and especially restenosis or rapid progression in non-dilated sites, on major spontaneous coronary events at long-term follow-up after a first successful coronary angioplasty performed for angina pectoris. A second aim was to assess the prognostic factors and especially restenosis in asymptomatic patients after angioplasty. The first 352 consecutive patients undergoing a successful coronary angioplasty were selected and followed-up. The following variables: age, sex, unstable angina, previous myocardial infarction, diabetes, hypercholesterolemia, tobacco consumption, hypertension, fibrinogen, coronary extent, single or multiple dilatation, restenosis, new progression, clinical deterioration of anginal status just before angiographic restudy or asymptomatic status were subjected to a stepwise regression analysis. Restenosis (a loss of 30% in diameter and/or a return to a >50% stenosis) and progression in non-dilated segments (a 20% reduction in diameter) were assessed by a computer-assisted method. Cardiac death, new myocardial infarction or new unstable angina, at long-term follow-up after angiographic restudy, were regarded as spontaneous coronary events and pooled in a single dependent variable. Thus 41 patients had a coronary event. In the overall population, clinical deterioration of anginal status (p<0.001, relative risk: 3.65) and fibrinogen (p<0.05, relative risk: 1.03) were independent predictors of spontaneous coronary events. Restenosis or new progression were not predictors. In asymptomatic patients (n=187), fibrinogen (p<0.01, relative risk=1.06) was the only predictor and restenosis was not an independent predictor of spontaneous coronary events. The best predictor of spontaneous coronary events at long-term follow-up after a first successful coronary angioplasty is clinical deterioration in anginal status in the months following the procedure. Restenosis does not appear as an independent predictor. Rapid progression observed in non-dilated sites is not an important prognostic factor.

Setting up equine embryo gender determination by preimplantation genetic diagnosis in a commercial embryo transfer program.

Preimplantation genetic diagnosis (PGD) allows identifying genetic traits in early embryos. Because in some equine breeds, like Polo Argentino, females are preferred to males for competition, PGD can be used to determine the gender of the embryo before transfer and thus allow the production of only female pregnancies. This procedure could have a great impact on commercial embryo production programs. The present study was conducted to adapt gender selection by PGD to a large-scale equine embryo transfer program. To achieve this, we studied (i) the effect on pregnancy rates of holding biopsied embryos for 7 to 10 hours in holding medium at 32 °C before transfer, (ii) the effect on pregnancy rates of using embryos of different sizes for biopsy, and (iii) the efficiency of amplification by heating biopsies before polymerase chain reaction. Equine embryos were classified by size (≤300, 300-1000, and >1000 µm), biopsied, and transferred 1 to 2 or 7 to 10 hours after flushing. Some of the biopsy samples obtained were incubated for 10 minutes at 95 °C and the rest remained untreated. Pregnancy rates were recorded at 25 days of gestation; fetal gender was determined using ultrasonography and compared with PGD results. Holding biopsied embryos for 7 to 10 hours before transfer produced pregnancy rates similar to those for biopsied embryos transferred within 2 hours (63% and 57%, respectively). These results did not differ from pregnancy rates of nonbiopsied embryos undergoing the same holding times (50% for 7-10 hours and 63% for 1-2 hours). Pregnancy rates for biopsied and nonbiopsied embryos did not differ between size groups or between biopsied and nonbiopsied embryos within the same size group (P > 0.05). Incubating biopsy samples for 10 minutes at 95 °C before polymerase chain reaction significantly increased the diagnosis rate (78.5% vs. 45.5% for treated and nontreated biopsy samples respectively). Gender determination using incubated biopsy samples matched the results obtained using ultrasonography in all pregnancies assessed (11/11, 100%); untreated biopsy samples were correctly diagnosed in 36 of 41 assessed pregnancies (87.8%), although the difference between treated and untreated biopsy samples was not significant. Our results demonstrated that biopsied embryos can remain in holding medium before being transferred, until gender diagnosis by PGD is complete (7-10 hours), without affecting pregnancy rates. This simplifies the management of an embryo transfer program willing to incorporate PGD for gender selection, by transferring only embryos of the desired sex. Embryo biopsy can be performed in a clinical setting on embryos of different sizes, without affecting their viability. Additionally, we showed that pretreating biopsy samples with a short incubation at 95 °C improved the overall efficiency of embryo sex determination.