Unusual Repair of Aortic Coarctation: Transcatheter Intervention Implications

J INVASIVE CARDIOL 2017;29(3):E41-E42.

Key words: aortic coarctation repair, transcatheter techniques

A 56-year-old male was evaluated for exertional dyspnea. He had previously undergone mechanical aortic valve replacement and aortic coarctation repair. On exam, a crisp prosthetic heart sound and a 4/6 continuous murmur in the upper precordium were auscultated, and peripheral pulse exam was normal; discordant upper- and lower-extremity blood pressure was absent. Nuclear perfusion imaging revealed a newly depressed ejection fraction and an anterior reversible perfusion defect. Following uncomplicated coronary angiography using Judkins left and right catheters, aortography revealed that the loud murmur was related to an unusual, extra-anatomic surgical repair, ie, transverse aorta to descending aorta bypass (Figure 1 and Video 1). 

This rarely used repair of aortic coarctation is accomplished via placement of a prosthetic graft bypassing the restricted aortic segment.¹ The course from the ascending or transverse aorta to the descending aortic anastomosis is variable and is tailored to the underlying aortic pathology. Common proximal anastomotic sites include the ascending aorta and the left subclavian artery. The transverse aorta is an uncommon proximal anastomotic point, but may have been useful in simplifying the approach for aortic valve replacement by sparing the ascending aorta. Possible courses include posterior or anterior to the inferior vena cava, superior to the pulmonary artery, or parallel to the distal aortic arch.² It is most often employed when restenosis occurs following operative or interventional repair of coarctation, but it is also useful for atypical forms of coarctation including long coarctation, aortic wall calcification, limited mobility of the aorta, or need for operative repair of co-existing cardiac pathology requiring median sternotomy. In obviating the need for total aortic cross-clamping and extensive descending aortic dissection, complications such as spinal cord ischemia, recurrent laryngeal nerve damage, and postoperative aneurysm can be reduced.^3,4 The specific bypass utilized in this case is uncommon, with a short course lying parallel to the distal aortic arch.

Recognition of an extra-anatomic surgical bypass of coarctation is important, as this repair would leave a continuous murmur on exam. At catheterization, a femoral arterial approach may lead to inadvertent crossing of the native coarctation, with resultant challenges in equipment delivery. An unexpected wire or catheter course may lead to confusion, but indicates entrance into the conduit. Once across the graft, tortuosity may limit catheter manipulation and the extra length might require longer catheters. We speculate that technical challenges of working through the graft may prove prohibitive. Utilization of a right radial arterial approach, as done in this case, simplifies cardiac interventional endeavors and eliminates the need to traverse the bypass conduit. If the coarctation is known to be distal to the ostium of the left subclavian artery, a left radial arterial approach may also be feasible. Given the variability of these extra-anatomic repairs, preprocedural non-invasive angiography may be helpful. A right radial approach offers the most likely successful and uncomplicated approach to the native coronary arteries. 

References

1.     Said SM, Burkhart HM, Dearani JA, Connolly HM, Schaff HV. Ascending-to-descending aortic bypass: a simple solution to a complex problem. Ann Thorac Surg. 2014;97:2041-2047; discussion, 2047-2048.

2.    Jatene MB, Celulari A, Miura N, Tanamati C, Carvalho VO, Marcial MB. Variant technique of extra-anatomic aortic bypass in aortic recoarctation. Arq Bras Cardiol. 2012;99:e149-e151.

3.    Morris RJ, Samuels LE, Brockman SK. Total simultanous repair of coarctation and intracardiac pathology of adult patients. Ann Thorac Surg. 1998;65:1698-1702.

4.    Preventza O, Livesay JJ, Cooley DA, Krajcer Z, Cheong BY, Coselli JS. Coarctation-associated aneurysms: a localized disease or diffuse aortopathy. Ann Thorac Surg. 2013;95:1961-1967. Epub 2013 May 2.

From ¹the Department of Medicine, Emory University School of Medicine, Atlanta, Georgia; ²Emory Heart and Vascular Center at St Joseph’s Hospital, Atlanta, Georgia; ³Mike O’Callaghan Federal Medical Center, Nellis AFB, Las Vegas, Nevada; and ⁴Department of Surgery, Emory University School of Medicine, Atlanta, Georgia.

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 September 7, 2016, final version accepted September 8, 2016. 

Address for correspondence: Anand D. Shah, MD, Emory Heart and Vascular Center at St Joseph’s, 5671 Peachtree-Dunwoody Rd, St 300B, Atlanta, GA 30342. Email: adshah7@emory.edu