Tricuspid valvular dynamics and 3-dimensional geometry in awake and anesthetized sheep

Abstract

General anesthesia did not alter tricuspid annular or subvalvular 3-dimensional geometry but reduced right ventricular contraction and tricuspid annular dynamics.

When should we assess tricuspid regurgitation severity? Preoperatively, while the patient is awake

“…After 1 week of recovery, the tricuspid valve was studied while the sheep were awake and then studied again with the sheep under general anesthesia. Jazwiec and colleagues 8 found that general anesthesia (1) was not associated with any substantial changes in systemic or pulmonary hemodynamics, (2) decreased systolic contraction of the tricuspid valve annulus secondary to decreased contraction of the septal portion of the annulus, (3) did not change the geometry of the right ventricle and subvalvular apparatus, (4) depressed the contractility of the free wall of the right ventricle, and (5) increased the severity of tricuspid regurgitation. Because there is no change in the geometry of the subvalvular apparatus, tricuspid regurgitation is likely related to decreased annular contraction during systole.…”

“…The effects of cardiopulmonary bypass were not studied by Jazwiec and colleagues. 8 Nonetheless, it is important to highlight that cardiopulmonary bypass and aortic crossclamping would likely exacerbate tricuspid regurgitation even further and perhaps more profoundly than general anesthesia alone. Cardiopulmonary bypass may adversely affect the severity of tricuspid regurgitation through several mechanisms, including (1) increased pulmonary vascular resistances and right ventricular afterload; (2) right ventricular dysfunction secondary to ischemia reperfusion, stunning, air embolization into the right coronary artery, or inadequate myocardial protection; and (3) abnormal interventricular septal motion.…”

“…Although Jazwiec and colleagues 8 are to be congratulated for their rigorous performance of complex and technically demanding experiments, the reader should be aware that the changes described were of marginal statistical significance and were limited to sheep, with no corroboration in human subjects. Recognizing these limitations, it is legitimate to ask what the clinical implications of these findings are, and how general anesthesia may affect our ability to assess tricuspid regurgitation severity.…”

Tricuspid valve regurgitation decreases after mitraclip implantation: Fluid structure interaction simulation

“…We used Smoothed Particle Hydrodynamics (SPH) [15] to simulate the effects of MC location on TV closure and regurgitation. Although there are a few numerical studies that focused on the TV [16][17][18], this is the first study that simulated the effects of MC on TR using an FSI model. Once validated [19], the results of this study would have potential clinical implications for optimal MC treatment for TR.…”

Commentary: Ongoing advancements in the understanding of tricuspid valve dynamics and functional geometry

“…To address this problem, Malinowski and colleagues 1 have developed a human model that uses ex vivo perfusion and surgically implanted sonomicrometry crystals, a protocol previously used in animal models. 2,3 Crystals implanted along the tricuspid annulus, right ventricular free wall, and right ventricular apex provide dynamic anatomic detail, while pressure transducers placed in the right atrium and ventricle provide hemodynamic data. Harvested hearts rejected for transplant, with no greater than mild right ventricular dysfunction or mild tricuspid regurgitation, are connected to an ex vivo perfusion system.…”