Interventional closure of LVOT to LA shunt after aortic valve replacement

Supported by the EuroIntervention Journal

Authors¹

Ina von Scheidt, Georg Waidhauser, Bastian Wein, Sébastien Elvinger, Philip W Raake, Eva Harmel

Case summary

A 79-year-old male patient was admitted to hospital with progressive dyspnea in New York Heart Association (NYHA) functional class III-IV and signs of fluid overload. Electrocardiogram showed new onset atrial fibrillation, and the NT-proBNP level at time of admission was elevated to 16,451 pg/ml (normal < 125 pg/ml).

Since past medical history revealed a status post aortic valve replacement with a bovine biological prosthesis, and clinical examination found a systolic heart murmur, an early valve deterioration of the biological prosthesis was assumed. Contrary to expectations, transesophageal echocardiography (TOE) showed excellent valve function of the bio prosthesis, and no signs of other valvular pathologies or lesions consistent with infective endocarditis.

However, a subannular perforation of left ventricular outflow tract (LVOT) in the region of fibrous aortomitral continuity was detected, thus resulting in a significant LVOT to left atrial (LA) shunt (Figure 1, left side), with a peak systolic LVOT-LA pressure gradient of 91 mmHg and both, severe LA and left ventricular enlargement. Right heart catheterization confirmed isolated postcapillary pulmonary hypertension, with pulmonary capillary wedge pressure of 23 mmHg, and elevated v-wave signal, consistent with significant LVOT-LA shunt.

Despite high doses of intravenous diuretics, recompensation was prolonged and poorly tolerated. Therefore, heart team decision was in favor of catheter-based shunt closure.

At first, a transaortic approach for shunt passage was chosen, using an internal mammary artery guiding catheter. Since no stable catheter position in the LVOT was achievable, the procedure was changed to a transseptal approach.

After TOE guided septal puncture, a 9-French steerable guiding sheath and a multipurpose guiding catheter were positioned in the LA, and a straight wire was successfully placed through the defect using 3D-TOE visualization.

The wire was then exchanged to a superstiff wire and an Amplatzer valvular plug III (Abbott, Santa Clara, U.S.A.) was successfully positioned. TOE confirmed an excellent functional result with only minimal residual shunt (Figure 1, right side).

The post-interventional course was uneventful and despite persisting atrial fibrillation, a sudden improvement in NYHA functional class was seen, and the patient was discharged three days later.

Aseptic intracardiac shunt lesions have to be considered as a rare complication in patients showing signs of heart failure after aortic valve replacement. Aggressive removal of annulus calcification, as well as the size of the implanted valve and the depth of prosthesis implantation, have to be taken into account.

In transcatheter valve replacement, shunts may occur due to enormous calcification resulting in microlesions during valve expansion or the delivery system itself might cause local damage^1,2,3.

Clinical symptoms differ, depending on shunt size. Especially unexplained volume overload should result in meticulous search for a perforation with shunt lesion⁴. Transthoracic echocardiography (TTE) and particularly TOE are the diagnostic cornerstone⁵.

Especially in frail patients with high surgical risk, catheter-based shunt closure represents an excellent alternative approach and is associated with less complications⁴.

Supplementary materials

References

1. Frigg C, Cassina T, Siclari F, Mauri R (2008) Unusual complication after aortic valve replacement. Interact Cardiovasc Thorac Surg 7:149-150.
2. Rojas P, Amat-Santos IJ, Cortes C, Castrodeza J, Tobar J, Puri R, Sevilla T, Vera S, Varela-Falcon LH, Zunzunegui JL, Gomez I, Rodes-Cabau J, San Roman JA (2016) Acquired Aseptic Intracardiac Shunts Following Transcatheter Aortic Valve Replacement: A Systematic Review. JACC Cardiovasc Interv 9:2527-2538.
3. Panoulas VF, O'Gallagher K, Mikhail GW (2013) Iatrogenic communications between aortic root and right ventricle/left atrium after transcatheter aortic valve replacement. Catheter Cardiovasc Interv 82:E603-608.
4. Konda MK, Kalavakunta JK, Pratt JW, Martin D, Gupta V (2017) Aorto-right Ventricular Fistula Following Percutaneous Transcatheter Aortic Valve Replacement: Case Report and Literature Review. Heart Views 18:133-136.
5. Ananthasubramaniam K (2005) Clinical and echocardiographic features of aorto-atrial fistulas. Cardiovasc Ultrasound 3:1.

Affiliation

1. Department of Cardiology, Respiratory Medicine, Intensive Care and Endocrinology, University Hospital Augsburg, University of Augsburg, Germany

Conflict of interest statement

None declared