SCAI Position Statement on Intracardiac Echocardiography to Guide Structural Heart Disease Interventions

Figures

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  Figure 1. Intracardiac echocardiography views. (A) Baseline views. (B) Mitral intervention views. (C) Left atrial appendage occlusion (LAAO) views. Ao, aorta; AoV, aortic valve; AV, aortic valve; IAS, interatrial septum; LA, left atrium; LAA, left atrial appendage; LV, left ventricular; MV, mitral valve; PFO, patent foramen ovale; PA, pulmonary artery; PV, pulmonary valve; RA, right atrium; RV, right ventricular; RVOT, right ventricular outflow tract; SVC, superior vena cava; TR, tricuspid regurgitation; TV, tricuspid valve.

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  Figure 2. Assessing anatomical factors that contribute to patent foramen ovale (PFO) risk. Assessment of risk begins outside the heart. From the hepatic portion of the inferior vena cava (IVC), the atrial septum can be visualized, and with it the embryonic remnants of the Eustachian valve that can funnel and accelerate IVC return onto the atrial septum (A). In the home view, a prominent Eustachian valve (EV) and ridge (ER) may be seen crossing the right atrium (RA) as the superior margin of the coronary sinus (B, C). A Chiari network (remnant of the embryonic sinus venosus) may be seen attached to the EV (D, E). With the probe rotated clockwise, and the knobs rotated posterior and left, the bicaval view with the septum lying horizontally is generated. In acute closure cases, thrombus in situ may be seen (F), such cases should be reassessed rather than closed. M-mode (available in some products) assessment for the presence or absence of a septal aneurysm requires multibeat acquisition, as inspiration is sometimes needed to reveal its presence (G). Ao, aorta; CS, coronary sinus; FO, fossa ovalis; IAS, interatrial septum; LA, left atrium; RV, right ventricular; RVOT, right ventricular outflow…

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  Figure 3. Assessing right-to-left shunt with intracardiac echocardiography. Shunt studies can be performed in the supine patient by advancing the catheter into the superior vena cava (SVC) for bubble injection and then withdrawing it to the inferior vena cava (IVC) for further injection. The patient can be asked to “sniff” or Valsalva if the rest injection is negative. Note that screening bubble echoes typically use the arm veins for bubble contrast injection; the SVC shunt underestimates the IVC shunt in approximately half of the patients. The example shown reveals why this is the case. SVC bubbles (A) are held off the oval fossa by strong IVC inflow washout (large arrow) (B), resulting in a weakly positive (<10 bubbles, small arrows) study from the SVC, but an uncountable number of bubbles from the IVC. IAS, interatrial septum; LA, left atrium.

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  Figure 4. Steps and complications of closure. With the right-to-left shunt demonstrated, the fossa ovalis can be probed with a catheter or soft wire to advance into the left atrium (LA). A stiff wire will stretch open the patent foramen ovale (PFO) and suggest the presence of a PFO tunnel if the left-sided exit is displaced from the right-sided entrance. (A) Wires and catheters should be screened for in situ thrombus formation during the case. Balloon measurements should only be made from ultrasound when the waist is seen with the central wire. The delivery system and the device advancing within the delivery system can be seen with ultrasound, reducing the use of X-rays. (B) The left disc should be formed in the mid LA, and (C) drawn onto the septum, before (D) the right disc is advanced to sandwich the primum and secundum septum between the discs. (E) Once the device is released, the final position should be documented, along with any anatomical concerns that may require attention in the future. IAS, interatrial septum; RA, right atrium.

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  Figure 5. Rim assessment. Rim assessment requires both probe rotation and angulation. The first appears as the probe is rotated away from the operator, as the mitral valve appears, and with it the aortic valve (AV) rim. Opposite the AV rim is the posterior rim. (A) The aortic rim is best assessed in the short-axis view of the AV, which requires a further rotation away from the operator, to about 5-o’clock and anticlockwise rotation of the ant/post knob to points#; the probe posteriorly showing the AV and the noncoronary cusp (NCC). At the opposite end of the aortic rim is the inferior vena cava rim. (B) As the middle knob is rotated, the superior rim will be seen until the superior vena cava rim appears and the intraatrial septum is displayed horizontally; the opposite end of this is the inferior vena cava/CS rim junction. (C) With a 3-dimensional (3D) probe, the entire volume is displayed with equivalent rims displayed by multiplanar reconstruction, from which sizing can be taken. LA, left atrium; RA, right atrium.

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  Figure 6. The left atrial appendage (LAA) viewed in far-field from the right atrium (RA). LA, left atrium; LV, left ventricular.

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  Figure 7. Intracardiac echocardiography imaging should confirm wire placement is not within the left atrial appendage. The pulmonary veins are visualized by clockwise rotation of the catheter from the bicaval view. Arrow, transeptal pigtail-shaped wire in the pulmonary vein. LA, left atrium; RA, right atrium.

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  Figure 8. Pericardial effusion assessment. (A) The presence of a pericardial effusion should be assessed prior to transseptal puncture and at the end of the procedure. This can be done through the 4-chamber view, which is acquired by advancing the intracardiac echocardiography catheter from a bicaval view to the junction of the right atrium (RA) and superior vena cava, followed by steep left flexion. (B) Advancing the probe into the right ventricular (RV) allows for circumferential assessment for effusion around the left ventricular (LV). LA, left atrium.

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  Figure 9. Intracardiac echocardiography visualization of the interatrial septum (IAS) during transseptal puncture. Both the long and short axes of the IAS should be visualized on intracardiac echocardiography to determine the location of the puncture site and to ensure procedural safety. (A) Baseline image of the bicaval and short-axis views of the IAS using biplane. The plane of the short-axis is 45° to 60° higher than the bicaval plane. (B) Tenting of the IAS by the transseptal sheath in a case with challenging anatomy due to a thick septum secundum, aneurysmal septum primum, and a small fossa ovalis. Ao, aorta; IVC, inferior vena cava; LA, left atrium; RA, right atrium; SVC, superior vena cava.

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  Figure 10. Two-dimensional (2D) vs 3-dimensional (3D) intracardiac echocardiography (ICE) for left atrial appendage closure. Two-dimensional ICE requires multiple probe positions to image the left atrial appendage (LAA) in orthogonal planes. In contrast, 3-dimensional ICE can provide multiplanar views simultaneously with a single probe position. Ant, anterior; CR, coumadin ridge; LAAO, LAA occlusion; LCX, left circumflex coronary artery; Pos, posterior.

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  Figure 11. Use of 3-dimensional (3D) intracardiac echocardiography (ICE) for tricuspid intervention guidance. 3D ICE with multiplanar reconstruction allows for assessment of catheter trajectory in the home view as well as corresponding biplane view (top left and right panels, respectively), providing excellent resolution to confirm tricuspid leaflet capture. The short-axis view provided in the bottom left panel and 3D image in the bottom right panel allow for real-time assessment of the entire valve anatomy. RA, right atrium; RV, right ventricular.

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  Figure 12. Three-dimensional intracardiac echocardiography in the left atrium: Mitral gradient, multiplanar reconstruction (MPR) area, and P2 length. Baseline mitral gradient, area, and P2 leaflet length for mitral transcatheter edge-to-edge repair.