Effect of variable annular reduction on functional tricuspid regurgitation and right ventricular dynamics in an ovine model of tachycardia-induced cardiomyopathy.

Objective: To investigate the effect of variable tricuspid annular reduction (TAR) on functional tricuspid regurgitation (FTR) and right ventricular (RV) dynamics in ovine tachycardia-induced cardiomyopathy.

Methods: Nine adult sheep underwent implantation of a pacemaker with an epicardial lead and were paced at 200 to 240 bpm until the development of biventricular dysfunction and functional TR was noted. During reoperation on cardiopulmonary bypass, 6 sonomicrometry crystals were placed around the tricuspid annulus (TA) and 14 were placed on the RV epicardium.

The influence of tricuspid annuloplasty prostheses on ovine annular geometry and kinematics.

Background: Surgical repair of functional tricuspid regurgitation is centered on annular reduction with artificial rings; however, the precise effect of prosthesis implantation on annular geometry, dynamics, and strain is unknown.

Methods: Forty healthy sheep had sonomicrometry crystals implanted around the tricuspid annulus and onto right ventricle free wall. Ten animals underwent tricuspid annuloplasty with a flexible Duran AnCore ring (Medtronic, Minneapolis, Minn) (28 ± 1 mm), 10 with Contour 3D rigid ring (Medtronic) (29 ± 1 mm), 10 with hybrid Tri-Ad Adams band (Medtronic) (28 ± 1 mm), and 10 had no prosthesis (control group).

Impact of tricuspid annular size reduction on right ventricular function, geometry and strain.

Objectives: Restrictive tricuspid annuloplasty is a clinically accepted approach to treat functional tricuspid regurgitation. We set out to investigate the effect of varying degrees of tricuspid annular reduction on the right ventricular (RV) function, geometry and strain.

Methods: Eight, healthy sheep (45 ± 4 kg) had 6 sonomicrometry crystals implanted around the tricuspid annulus and 20 onto the epicardium of the right ventricle defining 3 free wall regions: basal, mid and lower.

Right ventricular free wall stress after tricuspid valve annuloplasty in acute ovine right heart failure.

Background: Tricuspid annuloplasty rings may have a direct impact on right ventricular shape and free wall stress, potentially affecting chamber remodeling and recurrent regurgitation. In an acute model of ovine right heart failure, we investigated right ventricular free wall stress after annuloplasty with different prostheses.

Methods: Thirty-xix sheep underwent implantation of sonomicrometry crystals on the tricuspid annulus and right ventricle.

Sonomicrometry-derived 3-dimensional geometry of the human tricuspid annulus.

Objectives: Surgical correction of functional tricuspid regurgitation is focused on prosthetic reduction and remodeling of the tricuspid annulus. We set out to investigate the precise geometry of the human tricuspid annulus to better guide surgical therapy.

Methods: Eleven human donor hearts with normal right ventricular function and without tricuspid regurgitation that were rejected for clinical transplantation were harvested.

A fiduciary marker-based framework to assess heterogeneity and anisotropy of right ventricular epicardial strains in the beating ovine heart.

Quantifying ventricular deformation in health and disease is critical to our understanding of normal heart function, heart disease mechanisms, and the effect of medical treatments. Imaging modalities have been developed that can measure ventricular deformation non-invasively. However, because of the small thickness, complex shape, and anatomic position of the right ventricle, using these technologies to determine its deformation remains challenging.

Predicting bicycle helmet stage-of-change among middle school, high school, and college cyclists from demographic, cognitive, and motivational variables.

Objectives: To apply Prochaska's Transtheoretical model of behavior change to bicycle helmet use among middle school, high school, and college students.

Study Design: A battery of questionnaires was administered to cyclists in the seventh and ninth grades and to college students in Phoenix, Arizona (N=797). The battery included: (1) a question to determine respondent's stage of behavior change in Prochaska's Transtheoretical model; (2) items assessing the perceived pros and cons of helmet use; (3) a bicycle safety knowledge test; and (4) demographic information.

Prognosis in Duke's B colorectal carcinoma: the Jass classification revisited.

Objective: To assess whether Jass staging enhances prognostic prediction in Dukes' B colorectal carcinoma.

Design: A historical cohort observational study.

Setting: A university tertiary care centre, Switzerland.

Differential nitric oxide synthase activity in human platelets during normal pregnancy and pre-eclampsia.

1. Nitric oxide released from endothelial cells is a potent vasodilator that might play an important role in cardiovascular regulation during pregnancy. Platelets, like endothelial cells, contain a constitutive form of nitric oxide synthase.

Independent prognostic value of ploidy in colorectal cancer. A prospective study using image cytometry.

In a prospective study, the DNA content of Feulgen-stained nuclei obtained from fresh samples of 211 colorectal adenocarcinomas was evaluated by means of image analysis. The DNA histogram classification took into account aneuploidy and S-phase fraction for diploid cases. No significant relationship was found between ploidy and sex, age, preoperative carcinoembryonic antigen (CEA), size of the tumor, histologic differentiation, or Dukes' stage.

[Synchronous hepatic metastases of colorectal adenocarcinoma: what is the course? Apropos of 36 cases].

The discovery of synchronous hepatic metastases from colorectal cancer poses a tactical problem ticklish to resolve. What are favourable circumstances for curative excision of hepatic metastases? When and how to operate them? To try to respond, we analysed a collective of 36 patients between 10. 1.

[Prognostic value of DNA ploidy of colorectal tumor cells].

The analysis of ploidy provides valuable information allowing a more precise diagnosis, a more dependable prognostic and the choice of appropriate therapy. With ploidy analysis one can assess the aggressiveness of a given tumor. Aneuploidy of tumors clearly indicates a significantly lower patient survival index.