Novel Multiphase Assessment for Predicting Left Ventricular Outflow Tract Obstruction Before Transcatheter...

Area of Science:

• Cardiology
• Medical Imaging
• Interventional Cardiology

Background:

• Transcatheter mitral valve replacement (TMVR) patient selection is limited by perceived left ventricular outflow tract obstruction (LVOTO) risk.
• Current risk assessment using end-systolic computed tomography may overestimate LVOTO, leading to unnecessary screen failures.

Purpose of the Study:

• To propose and evaluate a dynamic physiologic assessment of LVOTO that accounts for systolic flow variations.
• To determine if multiphase and early systolic assessment of the neo-left ventricular outflow tract (LVOT) improves patient eligibility for TMVR.

Main Methods:

• Retrospective analysis of dynamic CT scans in 33 screen-failed and 29 treated patients to assess neo-LVOT area using multiphase average and early systolic values.
• Prospective evaluation in 9 patients using these novel methods, who would have previously failed screening based on end-systolic estimates.

Main Results:

• Screen failure for assumed LVOTO risk occurred in 27.6% of patients.
• Multiphase and early systolic assessments indicated a potential enrollment increase of 33.3% and 54.5% respectively for previously screen-failed patients.
• No clinical LVOTO was observed in the prospective cohort within 30 days post-procedure.

Conclusions:

• Multiphase, particularly early systolic, assessment of neo-LVOT offers a more accurate risk evaluation for LVOTO in TMVR.
• This refined approach can significantly expand patient eligibility for TMVR, potentially enabling treatment for over half of previously excluded individuals.