Intravascular ultrasound guided transcatheter electrosurgical revascularization of an interrupted aortic arch

Abstract

Interrupted aortic arch is a rare (prevalence 1:100000) but malignant cause of secondary hypertension, with late sequela of early myocardial infarction, stroke, and heart failure. We present the case of a 49-year-old male patient with aortic interruption successfully treated by intravascular ultrasound guided transcatheter electrosurgical wire crossing and revascularization using a covered stent.

Learning objective

Transcatheter electrosurgical wire techniques utilizing intravascular ultrasound facilitate safe and effective percutaneous revascularization of complex aortic coarctation patients.

Introduction

Interrupted aortic arch (IAA) is an uncommon congenital anomaly with a prevalence of 1:100000 births. Congenital IAA is a patent ductus arteriosus dependent lesion with early onset symptoms of tachypnea, cyanosis, acidosis, and congestive heart failure [Author: Please write out in full] necessitating emergent surgery on the neonate to facilitate survival. Numerous variants associated with a deletion in 22q11.2 – DiGeorge syndrome and associated congenital heart defects have been described [1]. Aortic interruption may also present in young children, adolescents, and adults. Whether the interruption is congenital or acquired during life from a missed critical coarctation is debated. Survival beyond infancy is predicated on arterial collateralization of the descending aortic limb. Common presentations among adults include refractory/emergent upper extremity hypertension, heart failure, stroke, and early coronary artery disease/myocardial infarction.

Case report

A 49-year-old Hispanic male with long standing systemic hypertension presented with complaints of chest discomfort. On examination, upper extremity hypertension of 180/90 mmHg, with faintly palpable bifemoral pulses with a lower extremity blood pressure of 90/50 mmHg was noted. Chest X-ray revealed an enlarged cardiac silhouette and widened mediastinum. Subsequent computed tomography scan was concerning for aortic coarctation. A transthoracic echocardiogram demonstrated sclerotic aortic valve with mild stenosis and insufficiency, moderate concentric left ventricular hypertrophy with diastolic dysfunction and preserved systolic function. Cardiac computed tomography angiography confirmed a Type A interrupted aortic arch, 17 mm distal to the left subclavian artery with normal branch anatomy. The region of atresia measured ~2–3 mm in length. Severe angulation (~100 degrees) was noted between the proximal and distal limbs with extensive collateral vessels perfusing the descending aorta, bypassing the region of aortic interruption (Fig. 1). Cardiac catheterization revealed calcified, tortuous coronary arteries with 60–70% stenosis of mid left anterior descending artery and obtuse marginal artery 1.

Fig. 1.

Cardiac computed tomography angiography with 3D reconstruction. (A) 3D reconstruction of interrupted aortic arch (IAA) with extensive posterior collaterals in anteroposterior view. (B) 3D reconstruction of IAA in left lateral view. (C) Sagittal section of the descending thoracic aorta showing the interrupted segment and the 100-degree obtuse angulation between the proximal and distal aortic limbs. AAo, ascending thoracic aorta; Distal Ao, proximal aortic limb; DAo, distal aortic limb.

Severe uncontrolled hypertension, upper extremity – lower extremity peak to peak gradient of 70–90 mmHg, and development of early coronary artery disease were indications for treatment [2]. A multidisciplinary heart team discussed surgical patch aortoplasty, aortic interposition graft, extra anatomic ascending to descending aorta bypass graft, and transcatheter intervention. Given the need for cardiopulmonary bypass, hemorrhagic risk from arterial collaterals encasing the IAA and risk of spinal compromise, patch aortoplasty and aortic interposition graft were deemed extremely high risk with poor outcomes [3,4]. Extra anatomic ascending to descending aorta bypass grafts, preferred in adults with IAA can be associated with prolonged pleural and mediastinal effusion, kinks, and re-obstruction [5]. Therefore, transcatheter intervention with recanalization of the interrupted aortic segment with a covered stent was planned.

Procedure in detail

Elective general anesthesia was administered. Ultrasound-guided right femoral venous (7Fr), right femoral arterial (14Fr), and left femoral arterial (6Fr) access was established. The right femoral arteriotomy was preclosed (Perclose Proglide™, Abbott, Abbott Park, IL, USA) prior to insertion of 14Fr Gore® DrySeal (W.L. Gore & Associates, Inc., Flagstaff, AZ, USA) sheath. A pigtail catheter in the descending aorta facilitated continuous pressure monitoring. Through a 5Fr left radial sheath, a 5Fr 3RDC diagnostic catheter was advanced to the left axillary artery. Ultrasound and intra-arterial marker catheter-guided left axillary access was obtained and a 12Fr sheath was inserted after preclosing the arteriotomy. A 40-50 mmHg peak gradient was recorded across the interrupted aortic segment. An 0.018″ intravascular ultrasound system (IVUS) (Boston Scientific, Natick, MA, USA) was inserted through the left axillary sheath and positioned in the proximal limb of the IAA to guide further intervention (Fig. 2C). A 10-mm gooseneck snare advanced through a 6Fr. PK1 (Medtronic, Minneapolis, MN, USA) guide via the axillary artery served as an additional fluoroscopic marker to guide electrosurgical wire traversal (Fig. 2C). An 8.5Fr steerable Agilis NxT (Abbott, Abbott Park, IL, USA) catheter was positioned in the distal aortic cap. A coaxial 5Fr multipurpose catheter was advanced to the area of interruption (Fig. 2C). Optimal positioning for guidewire traversal was ensured using biplane angiography (Fig. 2A, B). An Astato XS 0.014" (Asahi Intecc, Irvine, CA, USA) coronary guidewire with backloaded hubless PiggyBack® (Vascular Solutions, Minneapolis, MN, USA) catheter was inserted through the multipurpose catheter. The distal end of the wire was denuded of protective polytetrafluoroethylene coating and connected to the Bovie electrocautery pencil using clamps. The guidewire tip was extruded 1 mm to contact the distal cap and 40 W cutting energy was delivered. Wire passage into the proximal limb was noted but intraluminal wire position was not confirmed using IVUS (Fig. 2D). Wire was withdrawn, catheter was repositioned, and a repeat wire traversal with 60 W cutting energy was undertaken. The wire successfully traversed the atretic segment with luminal reentry as confirmed by IVUS (Figs. 2E, 3, Online Video 1) and angiography. This wire was snared out of the left axillary artery sheath. Serial dilations and catheter exchanges were undertaken with placement of a 12Fr. Mullins (Medtronic, Minneapolis, MN, USA) sheath with tip positioned distal to the origin of the left subclavian artery. A 35 × 40 mm covered CP stent (NuMED Inc., Hopkinton, NY, USA) on a 14 BIB balloon was appropriately positioned and deployed. Post dilatation was performed using a 16 × 20 mm Atlas™ (Bard, Tempe, AZ, USA) balloon. Angiography confirmed optimal positioning, stent expansion, and ruled out periprocedural dissection or perforation (Fig. 2F). Gradient post stenting decreased to ~5 mmHg. Arterial hemostasis was achieved by Perclose Proglide™ (Abbott, Abbott Park, IL, USA) suture without complications. The patient was discharged home in 48 h, post stable intensive care unit monitoring. At his 6-month follow-up visit he denied any symptoms of chest discomfort or exertional shortness of breath. He was able to be weaned off two antihypertensive medications and noted to have a blood pressure of 125/71 mmHg on amlodipine 5 mg daily, hydrochlorothiazide 25 mg daily, and metoprolol 25 mg twice a day.

Fig. 2.

Fluoroscopy of the interrupted aorta.

(A) Anteroposterior view. (B) Lateral view. (C) Anteroposterior view with coaxial Agilis catheter (yellow arrow) and multipurpose catheter (blue arrow) in the distal limb with intravascular ultrasound catheter (red arrow) and gooseneck snare (orange arrow) in the proximal limb with extensive collaterals (*) perfusing the distal limb. (D) Subintimal tracking of Astato wire (green arrow) on first traversal attempt. (E) Luminal reentry of Astato wire (green arrow) on second traversal attempt. (F) Revascularized aorta post stenting.

Fig. 3.

Intravascular ultrasound imaging of the proximal aortic limb.

Green arrow shows the wire traversing the atretic segment and reentering the proximal limb.

Discussion

Interrupted aortic arch is classified as Type A, B, C with subtype determined by the origin of the right subclavian artery [1]. Type, length, distortion angle, collateral anatomy, associated aneurysms, distance from major branch vessels, and associated congenital heart defects merit treatment individualization and predict short- and long-term outcomes [6]. Surgical extra-anatomic bypass between the ascending and descending aorta is preferred in adult IAA to avoid the collateral meshwork. While there is insufficient evidence regarding the best treatment for coarctation of aorta, when comparing open surgery vis-a-vis stent placement, no such data exist to guide decision-making in patients with an IAA [7]. Stent repair of IAA or coarctation of aorta is an alternative to surgical correction and provides excellent immediate and long-term results in young adults and children [6]. Stiff wire perforation and ablation catheter crossing of interrupted aortic segments have been described [8,9]. Mechanical perforation can be complicated by wire buckling, nontarget punctures and possible subintimal wire track compromising luminal crossing, jeopardizing collaterals and risking periaortic hematomas [8]. Ablation catheters are relatively large and allow for precise energy localization but increase the risk of hemorrhage on nontarget puncture [9]. Electrosurgical wire mediated aortic puncture for transcaval transcatheter aortic valve implantation and leaflet laceration for performance of the BASILICA and LAMPOON procedure have been described [10]. We employed electrosurgical wire traversal from the distal low-pressure limb to allow for on target traversal while minimizing bleeding risks. IVUS localization of luminal wire prevents subintimal tracking of wire/catheter with wire withdrawal and redirection. Traversal of the atretic segment was achieved in 28 min of electrosurgical wire insertion (total fluoroscopy time 45.7 mins) with successful stenting with minimal residual gradient.

In conclusion, transcatheter electrosurgical revascularization of the interrupted aorta with intravascular imaging guidance facilitates on-target traversal, prevents subintimal tracking, facilitating shorter procedural time and lower complication rate.

The following are the supplementary data related to this article.

Online Video 1

Intravascular ultrasound visualization of endoluminal traversal wire.

Declaration of competing interest

The authors declare that there is no conflict of interest.