Predictors of Left Ventricular Outflow Tract Obstruction After Transcatheter Mitral Valve Replacement

Pre-Operative Modeling of Transcatheter Mitral Valve Replacement in a Surgical Heart Valve Bioprosthesis

“…We found that the area of the neo-LVOT is about 271 mm 2 , and this value is quite higher than current clinical guidelines for TMVR. Indeed, we show that the neo-LVOT area is higher than the clinical cut-off of 100 mm 2 [1], which is considered a predictor of adverse outcomes related to neo-LVOT. Bioprosthetic valve leaflets longer than the implanted THV can also lead to prolapse into the neo-LVOT or infolding into the THV.…”

“…The evolution of catheter-based structural interventions has given patients less invasive alternatives to surgery; however, the current generation of transcatheter heart valves (THV) is not specifically designed for mitral position implantation and has an intrinsic geometry that may make mitral implantation suboptimal [1,2]. Indeed, while the term "transcatheter mitral valve replacement" (TMVR) is often used for the implantation of a dedicated transcatheter mitral valve in a native mitral anatomy, aortic transcatheter heart valves (THVs) are frequently used for transcatheter valve replacement in degenerated bioprosthetic mitral valves (i.e., valve-in-valve) [3,4].…”

The Year in Cardiothoracic and Vascular Anesthesia: Selected Highlights from 2019

“…48,49 Despite these advances, transcatheter mitral valve replacement has a small but important risk of left ventricular outflow tract obstruction that depends on factors such as septal dimensions, annular calcification, and the subannular profile of the selected mitral prosthesis. 50,51 The role of three-dimensional computed tomographic imaging is most valuable in this setting for preoperative calculation of left ventricular outflow tract area, taking into account the planned mitral prosthesis. 50,51 A predicted left ventricular outflow tract volume below 1.7 cm 2 has a 96.2% sensitivity and a 92.3% specificity for prediction of obstruction across the left ventricular outflow tract, defined as an increase in the mean gradient above 10 mmHg.…”

“…50,51 The role of three-dimensional computed tomographic imaging is most valuable in this setting for preoperative calculation of left ventricular outflow tract area, taking into account the planned mitral prosthesis. 50,51 A predicted left ventricular outflow tract volume below 1.7 cm 2 has a 96.2% sensitivity and a 92.3% specificity for prediction of obstruction across the left ventricular outflow tract, defined as an increase in the mean gradient above 10 mmHg. 50,51 This complication has been associated with a significant increase in periprocedural mortality (34.6% v 2.4%: p < 0.001).…”

Mechanisms, pathophysiology, and diagnostic imaging of left ventricular outflow tract obstruction following mitral valve surgery and transcatheter mitral valve replacement

“…Three-dimensional "printouts" of such computer generated models have also been utilized for risk prediction with promising results. Importantly, the various series that examined risk factors for LVOT obstruction post-TMVR have shown that the preprocedure anatomical characteristics determine the risk for LVOT obstruction 48,[51][52][53][54][55]. Treatment of post-TMVR LVOT obstruction includes medical optimization as well as bailout procedures, if required.…”