Da Vinci Anatomy Card #1: The Eustachian Valve and its Implications in Invasive Cardiology and Cardiac Surgery

Figures

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  Figure 1. Anatomical Drawing and Corresponding Gross Anatomy Specimen of the RA Structures and its Anatomical Relationships The EV arises from the anterior segment of the IVC and extends anteriorly as the ER below the FO and above the CS ostium. The free border of the ER becomes the TT extending into the CFB. The blue arrow represents the direction of a catheter or wire going into the anterior RA towards the RV when entering from an inferior approach, and showcases how a prominent EV/ER could hinder such approach. CFB = central fibrous body; CS = coronary sinus; ER = eustachian ridge; EV = eustachian valve; FO = fossa ovalis; IVC = inferior vena cava; RA = right atrium; RAA = right atrial appendage; RVOT = right ventricular outflow tract; TT = tendon of Todaro.

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  Figure 2. Histological Slide and Corresponding Gross Anatomical Specimen of the EV, ER, Septal CTI, Inferior Pyramidal Space Note the presence of prominent eustachian and Thebesian valves, as well as a large sub-EV recess. AVNa = atrioventricular nodal artery; CTI = cavotricuspid isthmus; RCA = right coronary artery; other abbreviations as in Figure 1.

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  Figure 3. Still Frame of ICE Image Displaying a Prominent Chiari Network, EV and ER Hindering Catheter Movement (ABL) During Typical Atrial Flutter Ablation Note the echo-bright area (red dotted circle) corresponding to the ablated area near the tricuspid valve. The 3D activation maps (top right, propagation; bottom right, isochronal right) show counter-clockwise activation across the CTI, including the EV/ER. This 3D anatomical view is generated by impedance and requires contact between the catheter and the tissue. This creates a “hollow” space (yellow dotted area in the mid CTI) where the prominent EV/ER lies, as the catheter is unable to generate geometry below these intracavitary structures. Using ICE and 3D mapping for guidance, a linear ablation lesion set was made in the lateral aspect of the CTI (blue tags, right bottom map) bypassing the prominent EV and ER in order to achieve bidirectional block. 3D = 3-dimensional; ABL = ablation catheter; CTI = cavotricuspid isthmus; ICE = intracardiac echocardiography.