A Novel Technique of Left Atrial Decompression Using Intracardiac Echocardiography Guidance in 2 Dogs With Advanced Degenerative Mitral Valve Disease

Figures

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  FIGURE 1. The ViewFlex Plus catheter and its phased‐array transducer (arrows) used for intracardiac echocardiography guidance in both dogs. Source: https://www.cardiovascuLar.abbott/us/en/hcp/products/electrophysiology/imaging‐diagnostic‐systems/viewmate‐ultrasound‐console‐and‐viewflex‐catheter.html (access 20th January 2025).

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  FIGURE 2. (A and B) Imaging guidance for interatrial septal puncture (Case 1). (A) Ventrodorsal angiographic image showing the double echocardiographic guidance used for the procedure with both ICE and TEE probes. Note also the steerable sheath (St. Sheath) over the 0.032″ J‐tip stiff guidewire (large arrow). (B) Two‐dimensional TEE view showing the stiff end of the 190‐cm 0.014″ straight‐tip guidewire crossing the interatrial septum (IAS). ICE: intracardiac echocardiography; LA: left atrium; LV: left ventricle; RA: right atrium; RV: right ventricle; TEE: transesophageal echocardiography.

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  FIGURE 3. (A and B) Combined intracardiac (A) and three‐dimensional transesophageal echocardiography (B) for guiding the steerable sheath (St. Sheath) across the interatrial septum (IAS), allowing access to the left atrium (LA; Case 1). (A) This 2D intracardiac echocardiographic image obtained with the ViewFlex Plus catheter placed in the right atrium (RA) near to the IAS shows the precise positioning of the St. Sheath into the enlarged LA after transseptal puncture. Note the markedly thickened anterior (AMVL) and posterior (PMVL) mitral valve leaflets associated with severe prolapse of the former within the LA cavity. (B) This three‐dimensional transesophageal echocardiographic image from the LA roof shows the correct positioning of the St. Sheath into the LA after crossing the IAS at the level of the fossa ovalis. Ao: aorta; LV: left ventricle; MVO: mitral valve orifice.

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  FIGURE 4. (A and B) These ventrodorsal angiographic view (A) and two‐dimensional intracardiac echocardiography image obtained with the ViewFlex Plus catheter placed in the right atrium (RA) near to the interatrial septum (IAS; B) show the atrial septostomy after transseptal puncture, using an 8‐mm NuMed Tyshak low‐pressure balloon catheter (Infinity Medical, Redwood, CA, USA; arrows) inflated to the rated pressure for 15 s (Case 1). ICE: intracardiac echocardiography; LA: left atrium; St. Sheath: steerable sheath; TEE: transesophageal echocardiography.

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  FIGURE 5. (A–C) Combined imaging guidance confirming the creation of a patent iatrogenic atrial septal defect (iASD) in Case 2. (A) Three‐dimensional (3D) transesophageal echocardiographic (TEE) en face view of the interatrial septum from the left atrium (LA), showing the 6.3 × 4.3 mm2 iASD (blue arrows). (B) This two‐dimensional intracardiac echocardiographic image using color‐flow Doppler mode with the ViewFlex Plus catheter placed in the right atrium (RA) near to the interatrial septum (IAS) confirms the patency of the iASD by visualization of a turbulent left‐to‐right interatrial shunting (gray arrow). (C) This 3D‐TEE image using color‐flow Doppler mode from the LA roof shows the patency of the iASD with a turbulent left‐to‐right interatrial shunting.