Comparative study on the relations between backfat thickness in late-pregnant gilts, mammary development and piglet growth.

The potential relation between body condition of gilts in late-pregnancy and litter BW gain as well as mammary development was studied using 2 sets of data. Gilts either from a commercial herd (Part 1, n = 182) or from a series of trials looking at mammary development (Part 2, n = 172) were separated in 3 groups according to backfat thickness (BF) on d 110 of gestation. Group categorization was similar for Parts 1 and 2 of the study and was: low (LOW), 13.6 ± 1.6 mm (mean ± SD); medium (MED), 17.6 ± 1.0 mm (mean ± SD); and high BF (HIGH), 21.8 ± 1.8 mm (mean ± SD) for Part 1, and LOW, 14.2 ± 1.3 mm (mean ± SD); MED, 18.1 ± 1.0 mm (mean ± SD), and HIGH 23.4 ± 2.6 mm (mean ± SD) for Part 2. The effects of BF group on piglet BW gain (Part 1) or on various mammary gland characteristics (Part 2) were determined using ANOVA. Litters from HIGH sows tended to have a greater lactation BW gain than those from LOW sows (P < 0.10). Sows with HIGH BF had more mammary parenchymal tissue and more total protein and total DNA than MED and LOW sows (P < 0.05), which led to greater total protein and total DNA contents (P < 0.05). There were strong positive correlations (P < 0.0001) between parenchymal weight and total protein, total DNA, and total RNA. Results suggest that it is beneficial for primiparous sows to have greater BF (i.e., 20 to 26 mm) at the end of gestation to achieve optimal mammary development and greater litter BW gain in the subsequent lactation.

Seventy-six month experience with the Omniscience cardiac valve.

Between August 1978 and September 1984, 440 patients were implanted with the Omniscience cardiac valve at three North American medical centers (210 aortic, AVR; 165 mitral, MVR; and 65 double valve replacements). Total follow-up was 1056 patient years; survivors were followed up to 76 months (mean 32), with 99% accountability. One hundred and eighty-six (42%) also underwent prior or concomitant major cardiac surgical procedures. Mean age was 56 +/- 12 years. Preoperatively, 3% were in New York Heart Association (NYHA) Class I, 18% II, 54% III, 26% IV. The 5 1/2 year actuarial survival rate for death from valve-related causes (thromboembolism, valve thrombosis, perivalvular leak) was 97% overall. The 5 1/2 year actuarial survival rate from all death causes was 78%. The complication rates, expressed as %/patient-year (endocarditis 0.7; anticoagulant-related hemorrhage 1.0; perivalvular leak 1.5; pannus/tissue overgrowth 0.6; and transient ischemic episode 1.2) demonstrate that advanced age at implant and additional major cardiac surgical procedures do not affect occurrence. Actuarial freedom from thrombotic complications (thromboembolism with residual deficit and valve thrombosis) at 5 1/2 years was 95% overall. Postoperatively, of 348 patients with known NYHA, 65% were in NYHA I, 28% II, 5% III, and 2% IV.

Clinical and hemodynamic assessment of the Omniscience prosthetic heart valve.

From 1980 to 1985, 154 Omniscience valve prostheses were implanted in 132 patients (mitral in 72, aortic in 33, and both in 27), 81 women and 51 men, aged 22 to 72 years. There were 13 early deaths (30 day mortality of 9.8%) and nine late deaths. The actuarial survival rate was 79.1% after 4 years, and survival rates after aortic, mitral, and multiple valve replacement were 71.8%, 80%, and 85.2%, respectively. After a postoperative follow-up period averaging 27 months, 96% of the survivors were in Class I or II. The linearized incidence of thromboembolism, hemorrhagic episodes, and reoperation was 3.8%, 3.4%, and 2.3% per patient-year, respectively. After 4 years, freedom from valve-related mortality, valve-related mortality and reoperation, thromboembolic episodes, and all valve-related complications was 93%, 89%, 88%, and 70%. Moderate hemolysis with increases of reticulocyte count and serum lactic dehydrogenase above normal values was found in 80% of the patients, but only one had hemolytic anemia. In 22 patients, the maximal opening angle of the prosthetic disc averaged 54 +/- 11 degrees. Postoperative hemodynamic evaluation was obtained in five patients with aortic prostheses and in 13 with mitral prostheses. Mean aortic gradient and effective orifice area averaged 17.6 mm Hg and 1.2 cm2 at rest and increased to 18.8 mm Hg and 1.7 cm2 with exercise. With mitral prostheses, these values averaged 6.5 mm Hg and 1.9 cm2 at rest and 15.4 mm Hg and 2.1 cm2 with exercise. Thus excellent clinical improvement is obtained with the Omniscience prosthesis; however, the hemodynamic performance of the valve and opening of the tilting disc are suboptimal, causing the prosthesis to be moderately obstructive to blood flow.

Factors influencing thromboembolic complications in Omniscience cardiac valve patients.

Clinical data were gathered over five years (650 patient-years) for all 155 aortic valve replacement, 125 mitral valve replacement and 46 double valve replacement patients implanted with the Omniscience cardiac valve prosthesis at three North American medical cent es. Mean age was 56 +/- 12 years, 80% were preoperatively in NYHA class III or IV, and 57% had previous or concomitant cardiac surgery. Data were evaluated for the incidence of thromboembolic complications. During the late postoperative period, transient ischaemic episodes occurred in six patients (0.92% per patient-year). The five-year actuarial thrombus-free rate for serious thromboembolic complications (valve thrombosis or thromboembolism with residual effects) for aortic valve replacement patients is 96% and 95% for mitral valve replacement patients. For patients experiencing any transient or serious thromboembolic complication, 35% had a compromise of coumadin anticoagulation shortly before the thromboembolic event, 60% had a history of atrial fibrillation, and 76% a history of rheumatic heart disease. Statistically, these rates are significantly higher compared with the original valve population. The low incidence of thromboembolic complications over this five-year clinical study demonstrates a commendable degree of safety and performance for the Omniscience valve.

Five-year clinical experience with the Omniscience cardiac valve.

Clinical data on the Omniscience cardiac valve prosthesis (sizes 19 to 31 mm) were obtained from 326 patients (155, aortic valve replacement [AVR]; 125, mitral valve replacement [MVR]; and 46, double-valve replacement) during a five-year period (650 patient-years) with 96% accountability. Mean age was 56 +/- 12 years, and 40% (130) of the patients were 61 years old or older. Thirty-one percent (101) had prior or concomitant coronary artery bypass grafting procedures, 9% (28) had a previous malfunctioning prosthesis, and 17% (57) had other cardiac surgical procedures. Eighty percent were in New York Heart Association (NYHA) Functional Class III or IV preoperatively. Early mortality was 10% (34). Five-year actuarial thrombus-free rate is 96% for patients who underwent AVR and 95% for patients having MVR. Postoperatively, 89% (172/193) were in NYHA Class I or II, and 84% (163/193) improved by at least one Functional Class. A significantly high proportion of the postoperative hematological values fall within normal ranges: red blood cell count, 94% (176/187); hematocrit, 88% (166/188); and hemoglobin, 93% (176/190). Ninety-eight percent (287/292) are free from clinical anemia. Four of the 5 patients with clinical anemia had a preoperative history of this condition. Levels of lactic dehydrogenase in 3 patients suggested the probable presence of clinically significant hemolysis, although all 3 have normal hematological values. Actuarial five-year survival for patients who underwent AVR or MVR are similar (82% and 80%, respectively), indicating satisfactory and comparable levels of safety and performance.(ABSTRACT TRUNCATED AT 250 WORDS)

Infective endocarditis update experience from a heart hospital.

In a retrospective study of 50 patients with infective endocarditis (IE), we found an overall mortality of 44%: among the 26 patients with natural valves (NV) the mortality was 19%; among the 24 with prosthetic valves (PV) it was 71%. Congenital heart disease was recognized in 17 of our cases, with a significant clustering in the NV group (50% vs 17%, p = 0.029); the most frequently encountered malformation was the bicuspid aortic valve. The incidence of rheumatic heart disease was 46% in the NV group and 83% in the PV group (p = 0.015). Manifestations of IE were protean and multisystemic. We calculated an average of 4.6 symptoms and 4.7 signs for each patient. Although sepsis was abated with appropriate antibiotics, death often ensued from multiple complications: congestive heart failure, arrhythmia, stroke, embolic myocardial infarction, valvular destruction or dehiscence, coagulopathy. New features of natural valve infective endocarditis are a rising incidence in the elderly and a survival rate seemingly at its peak. Features of prosthetic valve infective endocarditis include overwhelmingly frequent embolization to the central nervous system (p = 0.004), spleen (p = 0.009) and kidney (p = 0.010). Advances in therapy for this disease may come from early surgery in late prosthetic valve endocarditis and from future prospective studies to define how the host response influences the outcome.