Transcaval aortic valve implantation in a patient with Larsen syndrome: technical and anesthetic challenges

Abstract

Transcatheter aortic valve implantation has emerged as a therapeutic option for patients with symptomatic severe aortic stenosis who are inoperable, or at very high risk of open-heart surgery. Recently, we encountered a patient with aortic stenosis and Larsen syndrome, who had short stature, obesity, kyphoscoliosis, multiple musculoskeletal deformities, and severe restrictive lung disease. An open-heart surgery in such a patient involves substantial peri-operative risk. A successful transcaval aortic valve implantation was done under general anesthesia.

Introduction

Transcatheter aortic valve implantation (TAVI) procedure has emerged as a therapeutic choice in patients with severe aortic stenosis, who are considered inoperable because of multiple co-morbid conditions, or in whom open-heart surgery is expected to have poor outcome [1, 2]. Larsen syndrome is one such condition which is associated with multiple joint deformities, craniofacial anomalies, cleft palate, kyphoscoliosis, cervical spine deformities, short stature, hearing defects, and respiratory problems [3, 4]. Anesthetic challenges in patients with Larsen syndrome include difficulty in lying supine, risk of cervical cord injury, difficult intubation, and risk of respiratory complications. Small and tortuous femoral vessels can pose a technical challenge for the cardiologist and may increase the risk of vascular complications. In patients with small femoral arteries, alternative access approaches such as transapical, transcarotid, transaxillary/subclavian, direct aortic, and transcaval route are described in the literature [5]. We, hereby, describe a successful transcaval approach for TAVI in a patient with aortic valve disease. An extensive search using MEDLINE, Google Scholar, and PubMed Central showed no previous published report of TAVI in a patient with Larsen syndrome.

Case report

A 40-year old female, known case of Larsen syndrome and hypertension, visited our hospital for worsening of angina and breathlessness for last 1 month. Currently, she had Canadian Cardiovascular Society (CCS) class IV angina and New York Heart Association (NYHA) class IV breathlessness. Two-dimensional echocardiography revealed bicuspid, thickened aortic valve leaflets with severe aortic stenosis and moderate aortic regurgitation. Aortic valve area was 0.8 cm², aortic annulus was 21 mm, and peak/mean transvalvular gradients were 97/56 mmHg. Other cardiac valves, pulmonary artery pressure, aortic root dimensions, ventricular function, and coronary arteries were normal. The patient was a known case of Larsen syndrome and had short stature (height 120 cm, weight 48 kg), class I obesity (body mass index 33.3 kg/m²), flattened facial appearance with restricted mouth opening (two fingers), and kyphoscoliosis (Fig. 1). She also had musculoskeletal disorders in the form of bilateral genu valgus and congenital talipes equinovarus, for which she had undergone multiple lower limb-corrective surgeries. Currently, she could walk for a short distance with the aid of knee-braces and walker. Preoperative work-up showed severe restrictive ventilation defect on pulmonary function test (Table 1). Doppler ultrasonography of lower extremity arteries and computed tomography (CT) aortogram showed small caliber of femoral and iliac arteries (external iliac 4.3–3.9 mm, common femoral 3.2–3.0 mm, right and left side respectively). Patient’s EuroSCORE II was 1.57% (low-risk), and Society of Thoracic Surgeons (STS) score was 4.96% (intermediate-risk). Heart-team’s discussion with the patient favored TAVI over surgical replacement of aortic valve in view of her incapacitated life style and severe restrictive lung disease. Informed consent for TAVI procedure and to publish this case report was taken from the patient.

Fig. 1.

Photograph of the patient showing flattened facial appearance, short stature, scoliosis, and lower limb deformities

Table 1.

Pulmonary function test values

Parameter	Predicted value	Actual value	% Predicted value
FVC (L)	2.07	1.03	49.7
FEV1 (L)	1.89	0.87	46.0
FEV1/FVC (%)	76.3	79.6	104.4
PEFR (L/s)	4.57	2.37	51.8
TLC (L)	4.25	2.18	51.3
RV (L)	2.12	0.99	46.6
RV/TLC (%)	49.8	45.4	91.1

FVC forced vital capacity, FEV₁ forced expiratory volume in 1 s, PEFR peak expiratory flow rate, TLC total lung capacity, RV residual volume

The procedure was carried out in hybrid operating room using Artis Zeego imaging system. The patient was made to lie supine with the use of pillows and paddings for pressure points. Standard cardiac monitoring consisted of electrocardiogram, pulse oximetry, invasive blood pressure, central venous pressure, and multiplane transesophageal echocardiography (TEE). Difficult intubation kit was kept ready. After preoxygenation, anesthesia was induced with intravenous midazolam, fentanyl, etomidate, and cisatracurium. Video-laryngoscope and in-line manual stabilization of cervical spine were used for endotracheal intubation and insertion of TEE probe. Norepinephrine infusion and cardiopulmonary bypass were kept standby for any hemodynamic instability during the procedure. After achieving activated clotting time of > 250 s with the use of unfractioned heparin, transcaval approach, i.e., inferior vena cava (IVC) to aorta, was chosen in view of small size iliofemoral arteries. A coaxial crossing system was prepared, which consisted of a 0.014″–0.035″ wire convertor (PiggyBack® Wire Converter, Vascular Solutions), which expands the outer diameter of the 0.014″ guidewire and that facilitates delivery of the 0.035″ microcatheter into the aorta. A rigid tip coronary chronic total occlusion (CTO ) guidewire was backloaded to extend antegrade beyond the wire converter. The back end of the guidewire was connected to electrosurgery pencil using a clamp; and 50 W cutting mode current was used to gain access from IVC to aorta. Using orthogonal fluoroscopic projections, IVC to adjoining abdominal aorta access was obtained at L_2-3 level, by a snare positioned in the aorta (Fig. 2a). An 18-F introducer sheath was advanced along this tract from IVC to aorta. A 23-mm Myval™ valve (Meril Life Sciences, Vapi, India) was deployed under fluoroscopic and TEE guidance (Fig. 2b). The aortic entry site was sealed with 13-mm vascular stent graft. Post-procedure TEE showed a mean gradient of 12 mm across aortic valve, without any paravalvular/transvalvular leak. However, compression of the left main coronary artery was noted, for which 4 × 18-mm protection stent (XIENCE Xpedition, Abbott Vascular, India) was placed in the left main stem. Abdominal aortography and lower extremity angiography performed before and after the release of device showed no retroperitoneal accumulation of contrast. The procedure time was 90 min. Tracheal extubation was done 2 h later in the intensive care unit. Post-procedure care included anticoagulation with dual antiplatelet therapy followed by warfarin, analgesia with oral paracetamol, and breathing exercises/incentive spirometry as suggested by physiotherapy team. The patient made an uneventful recovery and was discharged on day 4. Follow-up at 3 months showed significant improvement in her symptoms to CCS and NYHA class I.

Fig. 2.

a Cine image showing entry of guidewire from inferior vena cava (arrow) towards a snare positioned in aorta (solid arrow). b Cine image showing deployed Myval™ transcatheter aortic valve (arrow), left mainstem stent (black arrow), tip of transesophageal echocardiography probe (arrow head), and right ventricular pacing lead (white arrow)

Discussion

TAVI performed via transcaval approach is a new alternative for patients with small caliber femoral arteries. Greenbaum et al. reported their experience with this technique to perform TAVI in 19 otherwise inoperable patients, with a success rate of 89% [6]. Another possible option in this patient would have been minimally invasive aortic valve replacement, but that also requires femoral artery cannulation and risk of vascular complications, if retrograde perfusion technique is chosen. Transapical approach requires thoracotomy with its consequential pulmonary complications in a patient with severe restrictive lung disease.

Larsen syndrome is a rare hereditary connective tissue disorder characterized by osteochondrodysplasia, large-joint dislocations, and craniofacial abnormalities. It results from the mutations of Filamin B (FLNB) gene located on the short arm of chromosome 3 (3p14) [4]. The cardiovascular manifestations in Larsen syndrome occur due to change in structure and activity of the cytoskeleton. Associated cardiac defects include endocardial cushion defects, mitral valve prolapse, bicuspid aortic valve, aortic stenosis, and aortic dissection/aneurysms.

General anesthesia was used on patient’s request, and in view of her difficulty in lying supine during the procedure. Anesthetic goals were avoidance of stress- and pain-induced tachycardia, maintenance of sinus rhythm and euvolemia, avoidance of systemic vasodilation, and control of oxygenation and ventilation. If cervical spine instability is present, intubation should preferably be performed by fibreoptic technique, keeping head and neck in neutral/stable position. These patients can become hypoxic rather rapidly due to lung hypoplasia and limited respiratory reserve resulting from restrictive lung disease [7]. Concomitant laryngotracheomalacia, though more commonly seen in children, can further contribute to respiratory complications after extubation. Patients with Larsen syndrome are at risk of cervical cord damage and secondary paralysis, suggesting use of extreme caution during intubation and TEE probe insertion.

Technological advancements over the last decade have improvised the catheter-based aortic valve replacement. Transfemoral access is the most preferred approach for TAVI; however, large sheaths and catheters used in the procedure increase the risk of vascular complications. Currently available sheaths and TAVI delivery catheters need a minimum femoral and iliac size of 5.5 mm, but ideally the size should be more than 6–6.5 mm. Transapical, carotid artery, subclavian artery, and direct aortic approaches are well described in the literature and transcaval approach is a new tool in the armamentarium [5, 8]. Iliofemoral veins are larger and more compliant than corresponding arteries, with low risks of bleeding and hemodynamic compromise. Aortic bleeding is shunted to a patent IVC hole because of the pressure applied from the adjacent retroperitoneal space. Closure of caval-aortic access site by using either vascular stent graft or nitinol occluder device has minimized the risk of retroperitoneal bleed [9]. However, the risks associated with this technique restrict its use by experienced operators in well-equipped centers.

Conclusion

Transcaval approach for TAVI for symptomatic severe aortic stenosis and Larsen syndrome with small size femoral arteries is a viable option, particularly in patients with high surgical risk. The procedure results in hemodynamic and symptomatic improvement in these patients, as was observed in this patient.

Authors’ contributions

All authors have contributed equally, and are responsible for the data presented.

Funding

Nil.

Compliance with ethical standards

Data transparency

All data are original.

Conflict of interest

The authors declare that they have no conflict of interest.

Research involving human participants and/or animals

This case report does not contain any studies with animals performed by any of the authors.

Ethical approval

All procedures performed in this case report were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.

Informed consent

Informed consent for the procedure, and to publish this case report was obtained from the patient. Additional informed consent was obtained from the patient to publish the photograph as this was essential for the scientific purpose. Complete anonymity was, however, not ensured.