Double Balloon Aortic Valvuloplasty in TAVI Era: Insight From Intracardiac Echocardiography and Multidetector Computed Tomography Findings

ABSTRACT: Retrograde double-balloon aortic valvuloplasty (DBAV) is a more effective method for decreasing the transvalvular gradient as compared to the conventional single-balloon technique for patients with severe aortic stenosis (AS). However, the potential risk of pressure-induced annulus injury remains a concern. In the present report, we describe a case of severe AS complicated with severe peripheral artery disease that was successfully treated with DBAV using bilateral brachial access. Multidetector computed tomography (MDCT) was used to measure the precise aortic annulus, and the procedure was guided by intracardiac echocardiography (ICE). Our findings suggest that DBAV is an effective method for achieving hemodynamic improvement, and our ICE findings combined with the MDCT measurements support the safety and efficacy of this historical technique.

J INVASIVE CARDIOL 2014;26(7):E95-E97

Key words: ICE, MDCT, aortic stenosis

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The advent of transcatheter aortic valve implantation (TAVI) drastically changed the therapeutic strategy for high-surgical risk patients with severe aortic stenosis (AS), and the value of percutaneous balloon aortic valvuloplasty (BAV) has been reconsidered as an effective bridging therapy to TAVI.1 Retrograde double BAV (DBAV) consists of the simultaneous inflation of 2 balloons and is a more effective method for decreasing the transvalvular gradient as compared to the conventional single-balloon technique for patients with severe AS.² However, the potential risk of pressure-induced annulus injury remains a concern.³

Case Report. A 78-year-old male with a previous history of ilio-popliteal bypass grafting for peripheral arterial disease (PAD) was referred to our center for evaluation of an asymptomatic AS prior to surgery for pancreatic cancer. Transthoracic echocardiography revealed degenerative aortic valve stenosis (mean pressure gradient, 40 mm Hg; indexed valve area, 0.6 cm²/m²) and moderate depression of left ventricular systolic function (ejection fraction, 44%). Aortic valve replacement by conventional surgery was considered high risk because of various comorbidities, including severe PAD. BAV was scheduled to reduce the risk of perioperative cardiovascular events because TAVI was not approved in Japan.

Multidetector computed tomography (MDCT) revealed occlusion of the left ilio-popliteal bypass and a severely diseased ilio-femoral access. Moreover, the bilateral superficial femoral arteries were occluded (Figure 1). Electrocardiogram-gated MDCT showed the aortic annulus was elliptical in shape (26 x 31 mm); the area-derived mean diameter was 28.5 mm (Figure 2). Retrograde DBAV using bilateral brachial access was planned for this patient with a large annulus and severe PAD.

Two 8 Fr 55 cm-long sheaths were inserted from each of the brachial arteries. After insertion of the sheaths, a bolus of intravenous heparin (80 IU/kg) was administered to achieve a target activating clotting time (ACT) of 250-300 seconds, and ACT was measured every 30 minutes thereafter. Two 15 x 30 mm Tyshak balloons (NuMED, Inc) were consecutively inflated under rapid ventricular pacing at 200 beats/minute (Figure 3; Video 1). The findings of intracardiac echocardiography (ICE) (AcuNav Ultrasound Catheter, Siemens Medical Solutions USA, Inc) confirmed good conformity of the 2 balloons to the long axis of the elliptical annulus (Figure 4; Video 2). Neither significant aortic regurgitation nor pericardial effusion was observed by intraprocedural ICE monitoring. The peak-to-peak gradient sufficiently decreased from 60 mm Hg to 30 mm Hg (Figure 5). The postoperative course was uneventful.

Discussion. To our knowledge, this report is the first to demonstrate an ICE image of DBAV, and the relative position of the 2 balloons corresponded well to the elliptical shape of the aortic annulus, which had been previously identified by preprocedural MDCT. A large aortic annulus is of great concern for achieving adequate reduction of a pressure gradient and improving the hemodynamics, and DBAV is occasionally required for this anatomy. However, uneven expansion of an annulus using double balloons has the potential risk of annular injury, and the access sites are likely to be limited because of the complications of severe PAD. Here, we achieved a hemodynamic improvement efficiently and safely using DBAV for a patient with a large annulus under the guidance of ICE and MDCT findings.

In the TAVI era, MDCT has emerged as a new gold standard for measurement of the aortic annulus because of its oval and three-dimensional structure.^4,5 We expanded the application of CT-guided measurements to a case of BAV for the purpose of more precise balloon sizing. In the present case, MDCT clearly demonstrated an elliptical aortic annulus (26 x 31 mm) with a mean diameter of 28.5 mm, and the balloon sizing was determined on the basis of this measurement. We intentionally selected balloons with a summed diameter (15 + 15 mm = 30 mm) that did not exceed the long-axis diameter of estimated aortic annulus by computed tomography scan (31 mm) to avoid catastrophic complication of annulus.

ICE is a novel imaging modality that allows a view within the cardiac chambers, including the valves, and can be used by interventional cardiologists. Recently, ICE has been applied to various procedures for the treatment of structural heart disease.⁶ Schwartz et al evaluated the feasibility of applying ICE for BAV using a canine model, and demonstrated its potential usefulness for assessing the wire and balloon position, evaluating aortic regurgitation, and detecting acute pericardial effusion.⁷ Although only a few cases of ICE-guided BAV have been reported, ICE has been shown to provide excellent imaging and guidance, which has minimized the need for contrast angiography and resulted in decreased radiation exposure.⁶ Our ICE findings demonstrated conformity of the 2 well-expanded balloons to the long axis of the elliptical annular shape and the absence of pericardial effusion. ICE can also be used under local anesthesia and might be applied to minimally invasive transfemoral TAVI with conscious sedation using local anesthesia.⁸

Conclusion. Our findings suggest that DBAV is an effective method for achieving hemodynamic improvement, and our ICE findings combined with the MDCT measurements support the safety and efficacy of this historical technique. DBAV using bilateral brachial access can be a promising approach, even for patients with a large annulus, for preserving borderline ilio-femoral access for future transfemoral aortic valve implantation.

References

1. Ben-Dor I, Maluenda G, Dvir D, et al. Balloon aortic valvuloplasty for severe aortic stenosis as a bridge to transcatheter/surgical aortic valve replacement. Catheter Cardiovasc Interv. 2013;82(4):632-637. Epub 2012 Nov 8.
2. Midei MG, Brennan M, Walford GD, et al. Double vs single balloon technique for aortic balloon valvuloplasty. Chest. 1988;94(2):245-250.
3. Mullins CE, Nihill MR, Vick GW, et al. Double balloon technique for dilation of valvular or vessel stenosis in congenital and acquired heart disease. J Am Coll Cardiol. 1987;10(1):107-114.
4. Hayashida K, Bouvier E, Lefevre T, et al. Impact of CT-guided valve sizing on post-procedural aortic regurgitation in transcatheter aortic valve implantation. EuroIntervention. 2012;8(5):546-555.
5. Messika-Zeitoun D, Serfaty JM, Brochet E, et al. Multimodal assessment of the aortic annulus diameter: Implications for transcatheter aortic valve implantation. J Am Coll Cardiol. 2010;55(3):186-194.
6. Vaina S, Ligthart J, Vijayakumar M, et al. Intracardiac echocardiography during interventional procedures. EuroIntervention. 2006;1(4):454-464.
7. Schwartz SL, Pandian NG, Kumar R, et al. Intracardiac echocardiography during simulated aortic and mitral balloon valvuloplasty: in vivo experimental studies. Am Heart J. 1992;123(3):665-674.
8. Hayashida K, Lefevre T, Chevalier B, et al. True percutaneous approach for transfemoral aortic valve implantation using the Prostar XL device: impact of learning curve on vascular complications. JACC Cardiovasc Interv. 2012;5(2):207-214.

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From the Department of Cardiology, Keio University School of Medicine, Tokyo, Japan.

Disclosure: The authors have completed and returned the ICMJE Form for Disclosure of Potential Conflicts of Interest. Dr Hayashida is a proctor for transfemoral-TAVI for Edwards Lifesciences. The remaining authors report no conflicts of interest regarding the content herein.

Manuscript submitted August 13, 2013, provisional acceptance given October 18, 2013, final version accepted November 6, 2013.

Address for correspondence: Kentaro Hayashida, MD, PhD, Department of Cardiology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan. Email: k-hayashida@umin.ac.jp