Stephen Maharaj1, Amanda-Marie Mc Carthy2, Risshi Rampersad1, Natasha Rahaman2, William R. Torres1, Jose Martinez1, Chadi Zeid2, Victor Rodrigiez1
1 Cardiology Department, Caribbean Heart Care Medcorp Ltd., St. Clair Medical Centre, Port of Spain, Trinidad and Tobago
2 Surgical Department, Caribbean Heart Care Medcorp Ltd., St. Clair Medical Centre, Port of Spain, Trinidad and Tobago
Corresponding author:
Stephen Maharaj
Email: [email protected]
DOAJ: 56cae91dc8af435181e92df934f2b7ec
DOI: https://doi.org/10.48107/CMJ.2024.12.002
Published Online: December 31, 2024
Copyright: This is an open-access article under the terms of the Creative Commons Attribution License which permits use, distribution, and reproduction in any medium, provided the original work is properly cited.
©2024 The Authors. Caribbean Medical Journal published by Trinidad & Tobago Medical Association
ABSTRACT
Transcatheter aortic valve implantation (TAVI) has provided patients who have been deemed high risk, or inoperable by conventional surgical valve replacement, with another method of having an aortic valve replacement without the need for major open-heart surgery.
We report in this case a TAVI via a transaortic approach on a 75-year-old woman who had no amenable peripheral vascular access for a transfemoral approach. Therefore, a transaortic approach was deemed appropriate.
This was the first performance of a TAVI via transaortic approach reported in Trinidad and Tobago and it illustrated a safe and effective strategy for TAVI in high-risk patients without eligible femoral access and severe aortic stenosis.
INTRODUCTION
A 75-year-old woman of East Indian descent, who was diagnosed with severe aortic valve stenosis and mild aortic valve regurgitation, was referred to our cardiology team in January 2023 as she was experiencing chest pain and shortness of breath on exertion during low to moderate levels of walking (NYHA (New York Heart Association) II-III/IV and CCS (Canadian Cardiovascular Society) class II/IV). The NYHA score indicates that she had marked limitations on physical activity but was comfortable at rest and the CCS score indicates that she had angina with moderate activity. She has a history of a coronary artery bypass graft (CABG) in 2005, type II diabetes mellitus and hypertension.
In February 2023, she had an echocardiogram (ECHO) which showed critical aortic stenosis, mild aortic valve regurgitation and moderate mitral valve regurgitation, with a preserved systolic function (ejection fraction 75%) and her mean gradient was 67 mmHg with an aortic valve area of 0.4 cm2.
She was reviewed by our surgical team for consideration of open-heart aortic valve replacement/repair surgery, however, the patient declined open-heart surgery and opted for a transcatheter aortic valve implantation (TAVI). She had an angiogram which showed severe native coronary atherosclerosis disease (CAD) of the left main artery: 60% distal lesion; left anterior descending (LAD) artery with mid-chronic total occlusion lesion; circumflex branch of the left coronary (LCx) artery 70% ostial lesion, left internal mammary artery (LIMA) graft to LAD and saphenous vein graft (SVG) to diagonal branch were patent, SVG to posterior descending artery (PDA) were not visible. A percutaneous coronary intervention (PCI) was performed with the successful insertion of one 3.5 x 15 mm Resolute Onyx stent in the left main to LCx artery.
She had a CT aortogram with TAVI protocol to assess the degree of the aortic stenosis and the patency of peripheral vessels. TAVI protocol was designed to capture high-resolution images that allow precise measurements from the aortic root to the femoral arteries. The CT scan showed severe calcifications in the aortic valve, arch of the aorta, abdominal aorta and the right and left iliac arteries. Severe stenosis was seen in both internal iliac arteries, both external iliac arteries and proximal femoral arteries. Calcifications were also seen in the subclavian arteries. The left femoral artery and left external artery diameters are 4.0 mm and 4.1 mm, respectively, while the right femoral artery and right external iliac are 6.2 mm and 4.5 mm, respectively. The Myval, an aortic valve prosthesis, requires a minimum circumference of 5.5 mm in all peripheral arteries for transfemoral access, which led to the decision of a transaortic approach.
The patient was extensively counselled on the risks of the procedure, including, but not limited to, the risk of pacemaker implantation, vascular bleeding complication, arterial perforation and the possible need for surgical intervention. A comprehensive risk assessment was conducted utilising two widely recognised predictive models, namely the European System for Cardiac Operative Risk Evaluation (EuroSCORE) II and the Society of Thoracic Surgeons Predicted Risk of Mortality (STS-PROM) score. The EuroSCORE II estimated the risk of operative mortality at 20.08%, while the STS-PROM score indicated a 10.2% risk of operative mortality.
This procedure was performed under general anaesthesia and with a transoesophageal echocardiogram in situ. Using the modified Seldinger’s technique, two puncture sets were placed via the left femoral vein and artery. The transvenous pacing wire was placed in the right ventricle for rapid pacing via the left femoral vein and then the arterial sheath 5Fr was inserted into the left femoral artery to place a pigtail in the ascending aorta. A 5 cm right anterior thoracotomy in the second intercostal space was performed to gain access to the ascending aorta and double purse strings with Ethibond 2/0 supported in a soft pledget. Heparin was administered and then a 6Fr introducer was placed on the right side of the ascending aorta 5 cm away from the aortic valve. An extra support wire was placed in the left ventricle and used as a temporary pacemaker during the procedure. The aortic valvuloplasty was performed with a balloon using a rapid pacing technique and the 23 mm Myval transcatheter heart valve was placed in the aortic position using the same rapid pacing technique. Finally, there was closure of the surgical thoracotomy with total hemostasis. An illustration of the TAVI pre and post placement can be seen in Figure 1 (E) and (F).
The patient’s total hospital stay was four days and her time in the intensive care unit was uneventful. She had no bleeding post-operatively. After her TAVI procedure, she underwent a post-op ECHO which revealed normal function of her 23 mm Myval transcatheter heart valve, with preserved systolic function (estimated ejection fraction 66%) and her mean gradient was 9 mmHg with an effective orifice area of 1.03 cm2.
DISCUSSION
Traditionally, aortic valve replacement has been performed via open heart surgery with the use of either a bioprosthetic or mechanical heart valve. Transcatheter aortic valve implantation (TAVI) has provided patients who have been deemed high risk or inoperable by conventional surgical valve replacement with another method of having their procedure done, without the need for major open-heart surgery1. Evaluation should include, but is not limited to, an echocardiogram or transoesophageal echocardiogram, coronary angiogram and a CT aortogram with TAVI protocol1.
An echocardiogram is the primary means of assessing the aortic valve. This valve echocardiogram should concentrate on determining the aortic valve area (AVA), mean pressure gradient, peak transvalvular velocity, calcification, left ventricular ejection fraction (LVEF) and thickness of the wall. Echocardiograms also help diagnose concomitant valve disease. There are four main classes of aortic stenosis and can be defined as follows:
- High-gradient aortic stenosis: mean gradient ≥ 40 mmHg, peak velocity ≥ 4.0 m/s, valve area ≤1.0 cm2 (or ≤ 0.6 cm2 / m2).
- Low-flow, low-gradient aortic stenosis with reduced ejection fraction: mean gradient <40 mmHg, valve area ≤ 1.0 cm2, LVEF ≤ 50%, stroke volume indexed (SVi) ≤35 mL/m2.
- Low-flow, low-gradient aortic stenosis with preserved ejection fraction: mean gradient <40mmHg, valve area ≤ 1.0 cm2, LVEF ≥50%, SVi ≤ 35 mL/m2.
- Normal-flow, low-gradient aortic stenosis with preserved ejection fraction: mean gradient <40 mmHg, LVEF ≥ 50%, SVi >35 mL/m2, valve area < 1 cm2.1
Low-dose dobutamine stress echocardiography (DSE) can be used to distinguish between true severe and pseudo-severe aortic stenosis (increase in valve area to >1.0 cm2 with increased flow) and identify patients with no flow (or contractile) reserve.
A cardiac CT scan during the investigation phase is important since it allows for assessment and sizing of the aortic valve, the aortic root and ascending aorta, the angle of implantation, the extent of valve and vascular calcification and importantly vascular access1. A minimal vessel lumen diameter (>5.5 mm) from the left or right femoral artery to the aortic valve is required to perform a transfemoral TAVI1. This is illustrated in Figures 1 and 2. A coronary angiogram is important to assess the need for concomitant coronary artery revascularization1.
Figure 1: Preoperative CT Aortogram. (A) The annulus plane shows notable calcifications in the annulus near the left coronary cusp (LCC), (B) Shows the calcifications on the aortic valve in the highlighted regions, (C) A view of the calcification seen in the subclavian artery, (D) 3D view of the subclavian artery, (E) Angiography pre-TAVI placement, (F) Angiography post TAVI placement in the aorta.
Figure 2: Preoperative CT aortogram shows a visual overview of the calcifications from the aortic arch to the bifurcation in the iliac arteries.
Indications for Intervention via Surgical Aortic Valve Replacement (SAVR) or Transcatheter Aortic Valve Implantation (TAVI)
The decision to intervene in cases of aortic stenosis depends on several factors specific to each patient, such as their age, overall health, anatomical considerations and patient preference. For both symptomatic and asymptomatic patients, the recommended options for intervention are either surgical aortic valve replacement (SAVR) or transcatheter aortic valve implantation (TAVI)1. These factors for consideration are summarized in Table 1.
Table 1. Comparison between surgical valve replacement (SAVR) vs transcatheter aortic valve implantation (TAVI)
| Surgical Aortic Valve Replacement (SAVR) | Transcatheter Aortic Valve Implantation (TAVI) |
| Patients under the age of 75 | Patients over the age of 75 |
| Patients who are at low risk for surgery (STS-PROM/ EuroSCORE II <4%) or those who are not eligible for transfemoral TAVI and are operable1 | Patients who are at high risk for surgery (STS-PROM/ EuroSCORE II >8%) or individuals who meet the criteria for TAVI, it is advised as the most suitable option1 |
TAVI Vascular Access Approaches
Transfemoral Approach
The transfemoral (TF) approach is the most common in TAVI, but up to 20% of patients who are candidates for TAVI have inadequate femoral vascular access and it is necessary to look for other routes5.
Transaortic Approach
The transaortic (TAo) approach is an alternative access route for TAVI in patients who are not suitable for the transfemoral approach. It involves accessing the aorta through a right thoracotomy, then a small incision is made in the ascending aorta, rather than through the apex of the heart (transapical approach) or the subclavian artery (trans-subclavian approach)2. The transaortic approach offers advantages including easy conversion to full median sternotomy in case of complications, feasibility of concomitant procedures in patients unsuitable for percutaneous coronary intervention, lower rates of cerebrovascular accident and paravalvular leak, as well as the ability to adapt to any commercially available device3.
Transaortic vs Transapical Approach
The transaortic approach in TAVI is considered a valid alternative to the transapical approach for patients with poor peripheral vascular anatomy. The transapical approach can have potential complications such as myocardial damage, bleeding, chest wall complications and pleural/pericardial effusions4. The transaortic approach aims to address these drawbacks by providing a safer and less invasive option for patients with limited peripheral vascular access4. It allows for easier access to the aorta and avoids potential complications associated with the transapical method. Overall, the transaortic approach is considered a safe and effective alternative access for TAVI, particularly in patients with poor peripheral vascular anatomy or quality4.
CONCLUSION
Transcatheter aortic valve implantation (TAVI) is a viable option for high-risk patients who cannot undergo conventional open-heart surgery. Patients with unfavourable peripheral vascular access can also benefit from having a transaortic valve implantation. This case report demonstrates safety and efficacy of using the transaortic approach for transcatheter aortic valve implantation (TAo-TAVI) in a patient who was not eligible for the transfemoral approach due to poor peripheral vascular anatomy, making it a promising alternative option for patients who require TAVI for which other approaches are contraindicated.
ETHICAL APPROVAL STATEMENT: Approved by the Ethics Review Board under Medcorp Limited with reference number CHCMSM1.
CONFLICT OF INTEREST STATEMENT: The authors declare that there is no conflict of interest.
INFORMED CONSENT STATEMENT: Written informed consent was obtained from the patient for publication of this case report and images used.
FUNDING STATEMENT: Not applicable
ACKNOWLEDGEMENTS: Participation by attending and resident medical staff of Caribbean Heart Care Medcorp Ltd is acknowledged.
AUTHORS CONTRIBUTION: The authors (Risshi Rampersad, Natasha Rahaman, William R. Torres, Jose Martinez, Chadi Zeid, Victor Rodrigiez) were responsible for the performance of parts of the surgery. The authors (Stephen Maharaj, Amanda-Marie Mc Carthy, Risshi Rampersad, Natasha Rahaman, William R. Torres) conceived and drafted/edited this manuscript. All authors read and approved the final manuscript.
REFERENCES
- Vahanian A, Beyersdorf F, Praz F, et al. 2021 ESC/EACTS Guidelines for the management of valvular heart disease: Developed by the Task Force for the management of valvular heart disease of the European Society of Cardiology (ESC) and the European Association for Cardio-Thoracic Surgery (EACTS). European Heart Journal 2021; 43: 561-632.
- Caskey M, Pan H, Kirshner M, et al. Transcatheter aortic valve replacement using the transaortic approach. Annals of Cardiothoracic surgery 2017 Sep 6; doi: 10.21037/acs.2017.09.05.
- Romano M, Daprati A, Saitto G, et al. Safety and effectiveness of a transaortic approach for TAVI: procedural and midterm outcomes of 265 consecutive patients in a single centre. Interactive CardioVascular and Thoracic Surgery 2019; 30: 400-7.
- Hayashida K, Romano M, Lefèvre T, et al. The transaortic approach for transcatheter aortic valve implantation: a valid alternative to the transapical access in patients with no peripheral vascular option. A single center experience. European Journal of Cardio-Thoracic Surgery 2013; 44: 692-700.
- Mosquera, V. X., Herrera-Noreña, J. M., Cuenca, J. J. Implante transcatéter valvular aórtico: ¿cuál es el mejor acceso alternativo? Cirugía Cardiovascular 2016; 23(4), 165-166; doi.org/10.1016/j.circv.2016.03.003
