Intra-cardiac echocardiography in alcohol septal ablation: a prospective comparative study against trans-thoracic...

Area of Science:

• Cardiology
• Medical Imaging

Background:

• Alcohol septal ablation (ASA) treats hypertrophic obstructive cardiomyopathy by reducing left ventricular outflow tract gradients.
• A significant portion of patients do not respond to ASA, potentially due to inaccurate infarct localization.
• Transthoracic echocardiography (TTE) can be challenging in the laboratory setting for visualizing myocardial contrast during ASA.

Purpose of the Study:

• To compare the efficacy of intracardiac echocardiography (ICE) versus TTE in assessing key anatomical structures and myocardial contrast during ASA.
• To evaluate the performance of ICE and TTE in visualizing mitral valve anatomy, target septum, and adjacent structures.

Main Methods:

• A prospective study involving 20 consecutive patients undergoing ASA.
• Paired TTE and ICE images were independently reviewed by two experts to assess specific anatomical domains.
• The ability to visualize myocardial contrast following septal arterial injection was assessed by the performing cardiologist.

Main Results:

• ICE demonstrated superiority in visualizing mitral valve anatomy (P=0.02).
• TTE was superior in assessing adjacent structures (P=0.002).
• ICE poorly visualized myocardial contrast in 17/19 patients due to acoustic shadowing and inadequate opacification, limiting its use in guiding ASA.

Conclusions:

• ICE is not suitable for guiding ASA due to its inability to clearly visualize myocardial contrast.
• TTE is substantially better for visualizing myocardial contrast during ASA.
• While ICE has limitations for contrast visualization, both ICE and TTE showed no significant difference in assessing overall cardiac anatomy relevant to ASA.