Transcatheter Aortic Valve Implantation With Either CoreValve or SAPIEN XT Devices in Patients With a Single Coronary Artery

Abstract: Transcatheter aortic valve implantation (TAVI) is associated with a risk of coronary obstruction. This complication is potentially lethal when the origin of the coronary arteries is anomalous. We describe two cases of TAVI with the SAPIEN XT (Edwards Lifesciences) and CoreValve devices (Medtronic) in patients with a single coronary artery. The tools and techniques used to anticipate the risk of acute coronary occlusion are discussed.

J INVASIVE CARDIOL 2012;24(7):342-344

Key words: TAVI, SAPIEN XT, CoreValve

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TAVI is a proven treatment for patients with symptomatic aortic stenosis with a high risk for conventional surgery.¹ The incidence of anomalous coronary arteries in this patient population remains unknown. From retrospective angiographic studies, a single coronary artery is seen in less than 0.05%, usually a left coronary artery originating from the right sinus of Valsalva.² This anatomical variant is relevant to TAVI, particularly because coronary obstruction occurs in ~1% of procedures³ and acute coronary obstruction in patients with anomalous coronary artery origin is even more complex. Little is known about the feasibility of TAVI in cases of a single coronary artery. We report two such cases: one patient treated with the Edwards SAPIEN XT valve (Edwards Lifesciences) and another treated with the CoreValve Accutrak device (Medtronic). We discuss the screening tests used to anticipate the risk of coronary obstruction.

Case 1

An 87-year-old female with severe calcific aortic valve stenosis and New York Heart Association (NYHA) class III dyspnea was referred to our institution for multidisciplinary discussion. Her past medical history included permanent atrial fibrillation, dual-chamber pacing for complete atrio-ventricular block, left carotid surgery, and chronic renal insufficiency (glomerular filtration rate, 26 mL/min). Transthoracic and transesophageal echocardiogram findings were as follows: indexed aortic valve area, 0.48 cm²/m²; mean aortic gradient, 60 mm Hg; peak velocity, 4.2 m/sec; preserved systolic left ventricular function; and aortic annulus diameter, 21 mm. The risk assessment confirmed a high-risk profile of the patient: logistic EuroSCORE was 20.94% and STS score was 10.3%. TAVI with a transfemoral approach was decided by the heart team.

Coronary angiography revealed a single coronary artery originating from the right sinus of Valsalva. The common trunk bifurcated into a right coronary artery (RCA) (which had a normal course) and a left coronary artery (LCA) which had a retro-aortic proximal course. This particular anatomy was confirmed by multi-slice computed tomography (MSCT; Figure 1). Particular attention was given to the distance between the coronary ostium and the aortic annulus: 15.3 mm in this patient. Sinus width and height were 30 mm and 19.1 mm, respectively.

This particular anatomy was therefore not considered a contraindication to the TAVI procedure because the coronary ostium was far enough from the aortic annulus and the sinuses of Valsalva were large enough to accommodate the TAVI prosthesis without compromising the single coronary artery origin. Prior to the implantation of a 23 mm Edwards SAPIEN XT valve, a valvuloplasty was performed (23 mm balloon) with concomitant aortography, confirming the patency of the coronary artery (Figure 2). TAVI was successfully carried out without any coronary obstruction or significant paravalvular leakage. On day 2, MSCT was obtained; the prosthesis was correctly positioned, without obstruction of the coronary artery (Figure 3). At 12-months follow-up exam, the patient was in NYHA II class, without any clinical events.

Case 2

The second patient is an 89-year-old female in NYHA class III who was referred to our institution for assessment of TAVI feasibility. Her past medical history was paroxysmal atrial fibrillation and stroke. Transthoracic and transesophageal echocardiography showed severe aortic valve stenosis (indexed aortic valve area, 0.5 cm²/m²; mean aortic gradient, 77 mm Hg; peak velocity, 4.2 m/sec) with preserved left ventricular systolic function. Aortic annulus diameter was 23 mm. Since the logistic EuroScore and the STS score were 26.7% and 11.8%, respectively, transfemoral TAVI was decided by the heart team.

Coronary angiography showed a single coronary artery arising from the right sinus of Valsalva. Once again, the common trunk bifurcated into an RCA that had a normal path and a less developed LCA with a retro-aortic proximal course. This particular anatomy was confirmed by MSCT (Figure 4). The distance between the coronary ostium and the aortic annulus was 12 mm.

During the procedure, predilation of the aortic orifice with a 22 mm balloon with simultaneous aortography confirmed the patency of the unique coronary artery at maximum balloon inflation prior to the successful delivery of a 26 mm Medtronic CoreValve Accutrak prosthesis without any significant leakage.

MSCT performed on day 2 demonstrated the correct position of the CoreValve, 4 mm below the aortic annulus, with a patent coronary artery (Figure 5).

At 6-month follow-up exam, the patient was in NYHA class II, without any clinical event.

Discussion

Little is known about the safety of TAVI in patients with anomalous coronary arteries. Few cases have been reported thus far. Giovanni et al published a case of successful implantation of a Medtronic CoreValve in a patient with a left circumflex artery (LCX) coming from the right coronary sinus, while the RCA and left anterior descending artery were normal. The choice of a self-expanding device was guided by an estimated higher risk of LCX obstruction with the balloon-expandable device.⁴ Using the same arguments, Weich et al successfully implanted an Edwards SAPIEN prosthesis in a patient with an RCA coming from the left sinus of Valsalva with an anterior course.⁵ We demonstrate here that TAVI is feasible in cases of a single coronary artery, arising in the right sinus of Valsalva, with both the SAPIEN XT and CoreValve devices. One device does not appear particularly advantageous over the other. The most important points are careful patient selection and accurate imaging.

The risk of coronary obstruction and subsequent death is intuitively high in this group of patients. The main risk is an obstruction of the unique coronary artery by a bulky calcified leaflet. In our cases, the risk of any external compression of the abnormal LCA, in its retro-aortic course, seems very low. Indeed, it is unlikely that the anomalous vessel would be compressed against any fixed structure in taking this course, since no portion of the single artery appears intramural. Moreover, there does not appear to be a split-like origin to either the RCA or the origin of the LCA from the right sinus of Valsalva. The anticipation of such a life-threatening complication relies on the appropriate sizing of the annulus and an appreciation of the relative distance from the aortic annulus to the coronary ostium. The precise analysis of the dimensions of the sinuses of Valsalva is also paramount; sinuses should be wide and high enough to decrease the risk of coronary occlusion either by a bulky calcified leaflet or the frame of the prosthesis. MSCT is the tool of choice to analyze these parameters and precisely define the coronary arterial anatomy and its course. Angiography during balloon valvuloplasty is also of major importance to anticipate any risk of coronary obstruction prior to valve insertion. The balloon-annulus ratio should be close to 1. This technique is routinely applied in our institution for all TAVIs, since it provides three types of information: further appreciation of the annulus diameter; estimation of the risk of coronary obstruction; and anticipation of valve embolization, particularly in cases of implantation of the SAPIEN XT device in patients with severe septal hypertrophy. The appropriate valve-annulus ratio has to be defined for each patient prior to the procedure; a 1/1 ratio seems reasonable. Indeed, the oversizing of the prosthesis should be minimized to avoid coronary compression.

In cases where coronary obstruction occurs during balloon valvuloplasty, Stabile et al proposed placing a 0.014˝ angioplasty guidewire in the coronary artery prior to prosthesis implantation to be able to quickly deal with any abrupt coronary occlusion. This technique has been adopted in several cases of left main coronary obstruction with normal coronary arteries.⁶ In patients with anomalous coronary arteries, the utility of this preventive technique would have to be considered (along with other potential risks) by the heart team prior to the procedure.

Conclusion

We have demonstrated that TAVI can be safely performed in carefully selected patients with a unique coronary artery originating from the right sinus of Valsalva. Both the Edwards Sapien XT and the Medtronic CoreValve prosthesis can be used in these patients. The risk of coronary obstruction can be anticipated by a complete analysis of the aortic root anatomy using MSCT. Balloon valvuloplasty aortography is helpful for the final assessment of coronary patency prior to prosthesis implantation.

References

1. Tchetche D, Dumonteil N, Sauguet A, et al. Thirty-day outcome and vascular complications after transarterial aortic valve implantation using both Edwards SAPIEN and Medtronic CoreValve bioprostheses in a mixed population. EuroIntervention. 2010;5(6):659-665.
2. Boissier F, Coolen N, Nataf P, et al. Sudden death related to an anomalous origin of the right coronary artery. Ann Thorac Surg. 2008;85(3):1077-1079.
3. Thomas M, Schymik G, Walther T, et al. Thirty-day results of the SAPIEN aortic Bioprosthesis European Outcome (SOURCE) Registry: a European registry of transcatheter aortic valve implantation using the Edwards SAPIEN valve. Circulation. 2010;122(1):62-69.
4. Giovanni Mennuni M, Pagnotta P, Presbitero P. Percutaneous aortic valve implantation in severe stenosis associated with anomalous origin of the circumflex coronary artery. Eur Heart J. 2011;32(13):1687.
5. Weich H, Ackermann C, Viljoen H, et al. Transcatheter aortic valve replacement in a patient with an anomalous origin of the right coronary artery. Cathet Cardiovasc Interv. 2011;78(7):1013-1016.
6. Stabile E, Sorropago G, Cioppa A, et al. Acute left main obstructions following TAVI. EuroIntervention. 2010;6(1):100-105.

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From the Clinique Pasteur, Groupe CardioVasculaire Interventionnel, Toulouse, France.
Disclosure: The authors have completed and returned the ICMJE Form for
Disclosure of Potential Conflicts of Interest. The authors report no conflicts of interest regarding the content herein.
Manuscript submitted February 22, 2012, provisional acceptance given March 15, 2012, final version accepted May 7, 2012.
Address for correspondence: Didier Tchetche, MD, Clinique Pasteur, Groupe CardioVasculaire Interventionnel, 45 avenue de Lombez, 31300, Toulouse, France. Email: d.tchetche@clinique-pasteur.com