Aorto-Right Ventricular Fistula after Transfemoral Aortic Valve Implantation

ABSTRACT: A 91-year-old female patient presented with worsening exertional dyspnea 1 month after transfemoral aortic valve implantation using an Edwards Sapien valve. She was found to have a paraprosthetic sinus of Valsalva rupture with a left-to-right shunt into the right ventricular cavity. The patient underwent coil closure of the defect with successful shunt elimination.

J INVASIVE CARDIOL 2010;22:E30–E31

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Case Report. A 91-year-old female with severe, symptomatic aortic stenosis (mean transvalvular gradient 59 mmHg, valve area 4 mm2) was referred for evaluation of transcatheter aortic valve implantation. The aortic valve annulus measured 22 mm as assessed by transesophageal echocardiography (TEE) and computed tomographic (CT) angiography, and peripheral access was deemed adequate for insertion of a 24 French (Fr) delivery sheath. Following predilatation with a 20 x 40 mm balloon (Nucleus, Numed, Inc., Cornwall, Ontario, Canada), a 26 mm Edwards Sapien prosthesis (Edwards Lifesciences LC, Irvine California) was successfully implanted during rapid right ventricular pacing. Control angiography and simultaneous TEE showed correct position of the valve prosthesis with only minimal central regurgitation (Figure 1). There was no need for postdilatation. Following femoral artery sheath removal, rupture of the iliac artery resulted in severe bleeding and was successfully treated with implantation of a 10 x 60 mm Fluency covered stent (Bard, Murray Hill, New Jersey). The hospital stay remained uneventful and predischarge transthoracic echocardiography (TTE) showed adequate position and function of the bioprosthesis. One month after the intervention, the patient complained of decreasing exercise tolerance and worsening exertional dyspnea. Upon physical examination, a new grade 3/6 continuous murmur along the right sternal border was noted. Her blood pressure and pulse were within normal limits, and she denied any fever or chills. Laboratory work-up including complete blood count and serum chemistry were within normal limits. Electrocardiography (ECG) showed normal sinus rhythm with known left bundle branch block. Color-flow Doppler echocardiography detected a jet between the aortic root and the right ventricle, suggesting rupture of the right sinus of Valsalva resulting in a left-to-right shunt. The bioprosthetic valve was well-seated and free of significant regurgitation. The patient was then referred to our facility for treatment of the shunt. TEE confirmed a 4 mm long fistula with a diameter of 2 mm extending from the right coronary cusp into the right ventricle in close proximity to the implanted valve. There was no evidence of vegetations or abscess formation. Cardiac catheterization revealed normal filling pressures and confirmed a significant step-up in oxygen saturation from 68% in the right atrium to 76% in the pulmonary artery, proving a left-to-right shunt with a Qp:Qs of 1.4:1. Contrast angiography of the ascending aorta showed brisk flow into the right ventricular cavity. Following diagnosis of rupture of the sinus of Valsalva, the decision to perform percutaneous closure was made owing to the patient’s symptoms. Under general anesthesia with endotracheal intubation and TEE guidance, a 4 Fr left 3.5 Judkins was retrogradely advanced and seated in the fistula. The defect was crossed with a 0.035 inch Terumo guidewire (Terumo Medical Corp., Somerset, New Jersey) and the guiding catheter advanced through the fistula (Figure 2). Subsequently, the guidewire was removed and an IMWC-5-PDA5 coil (MReye Flipper Detachable Embolization Coil Delivery System, Cook, Inc., Bloomington, Indiana) advanced and successfully placed into the defect. The distal end of the coil was placed in the right ventricular outflow tract. Contrast angiography and TEE confirmed near-elimination of the left-to-right shunt upon coil delivery (Figure 3). The following day, TTE confirmed a good result and the patient was discharged to the referring hospital. Outpatient follow up documented adequate uneventful recovery. TTE 5 months after fistula closure showed a small, nonsignificant residual shunt from the aortic sinus to the right ventricle. The patient remained asymptomatic under medical treatment. Discussion. Aorto-cardiac fistulas may result from endocarditis, trauma or rupture of aneurysms of the sinus of Valsalva.¹ They also have been reported as a rare complication following aortic valve replacement surgery (AVR).² Transcatheter aortic valve implantation (TAVI) has been shown effective in selected elderly patients with severe aortic stenosis at high risk for surgical valve replacement. Potential mechanisms leading to paraprosthetic fistulas following surgical aortic valve replacement have been related to surgical technique and cannot be translated into the population undergoing TAVI. To the best of our knowledge, this is the first report of an aorto-right ventricular fistula after transfemoral implantation of a balloon-expandable stent valve. Following balloon dilatation of the stenosed aortic valve, the balloon-expandable Edwards-Sapien bioprosthetic stent valve is passed retrogradely through the aorta on a steerable guiding catheter and positioned within the native aortic annulus. Inflation of the delivery balloon during rapid right ventricular pacing expands the stent valve and anchors the prosthesis within the native annulus. In the present case, the bioprosthesis was correctly positioned and the size adequate according to the manufacturer’s recommendations. A favorable short-term result was documented by echocardiography prior to discharge. Subsequently, stent struts of the bioprosthesis may have eroded the aortic root, resulting in the aorto-cardiac fistula. Percutaneous closure of paraprosthetic leaks using atrial septal occluders, patent ductus arteriosus occluders and coils have been previously reported.^3,4 Owing to the small size of the fistula, the decision was made to close the fistula by means of a coil. References

1. Vural KM, Sener E, Tasdemir O, Bayazit K. Approach to sinus of Valsalva aneurysmas: a review of 53 cases. Eur J Cardio Thorac Surg 2001;20:71–6. 2. Roy D, Saba S, Grinberg I, et al. Aorto-right ventricular fistula: a late complication of aortic valve replacement. Tex Heart Inst J 1999;26:140–142. 3. Pate G, Thompson CR, Munt BI, Webb JG. Techniques for percutaneous closure of prosthetic paravalvular leaks. Catheter Cardiovasc Interv 2006;67:158–166. 4. Pate G, Zubaidi AA, Chandavimol M, et al. Percutaneous closure of paravalvular leaks: Case series and review. Catheter Cardiovasc Interv 2006;68:528–533.

______________________________________ From the Swiss Cardiovascular Center Bern, University Hospital, Switzerland. Disclosures: Dr. Pilgrim has nothing to disclose. Dr. Meier received consultancy fees, grants and honoraria from AGA Medical. Dr. Wenaweser received honoraria from Medtronic CoreValve and Edwards Lifesciences. Manuscript submitted July 23, 2009, provisional acceptance given September 8, 2009, final version accepted September 16, 2009. Address for correspondence: Peter Wenaweser, MD, Swiss Cardiovascular Center Bern, University Hospital, 3010 Bern, Switzerland. E-mail: peter.wenaweser@insel.ch