The American College of Cardiology (ACC) and the American Heart Association (AHA) ended 2020 by publishing updated guidance on the management of valvular heart disease. This document covered significant ground with regards to transcatheter aortic valve replacement (TAVR) and transcatheter mitral valve repair.
The decision between TAVR and surgery remains crucial
TAVR has revolutionized the management of symptomatic severe AS, and indications are expanding toward treating younger and lower risk patients. Both the Evolut low risk trial and the PARTNER 3 trial provide evidence that the use of TAVR extends beyond the scope of high and intermediate risk surgical patients and is at the very least equivalent to surgical aortic valve replacement (SAVR) in the treatment low-risk surgical candidates, when using a transfemoral approach in patients without bicuspid aortic valves1,2.
The ACC/AHA guidance recommends that patients between the ages of 65 and 80 years old make that determination through shared decision making, and noted that both SAVR and TAVR have their own advantages and disadvantages3.
They stated that characteristics including bicuspid aortic valve, left ventricular outflow tract obstruction, pre-existing severe or multi-vessel coronary artery disease, or concomitant disease of a second valve would favour SAVR; even in carefully selected older and frailer patients over the age of 803.
Meanwhile: shorter estimated life expectancy, a severely calcified or porcelain ascending aorta, significant co-morbidity including severe renal impairment or lung disease, and limited ability for rehabilitation after SAVR tend to favour TAVR3.
Surgical mitral valve repair/replacement or transcatheter edge-to-edge mitral valve repair?
Transcatheter mitral interventions including mitral repair and replacement have lagged in comparison to TAVR because of the relatively more complex mitral valve anatomy, pathophysiology, and procedural characteristics. A gargantuan amount of money has been invested in mitral valve technology over the past half-decade (over 2.5 billion), secondary to the heightened interest in seeing transcatheter mitral technology develop similarly to TAVR4.
Mitral regurgitation (MR) is the most common valvular pathology, with a 10% prevalence in the general population. Combined with increasing life expectancy and prevalence of heart disease, the incidence of primary and functional secondary MR will only increase5,6. Less than half of patients with MR who meet the indication for surgery, do not receive appropriate intervention, usually due to the high risk associated with their age and comorbidities5,7.
Recent evidence supports careful analysis of the valve area and left ventricular function in addition to the left atrial hemodynamics in order to improve outcomes following transcatheter mitral valve repair8,9. Subsequently, the United States Food and Drug Administration (FDA) indications for MitraClip use was updated to include only symptomatic patients who were receiving maximally tolerated medical therapy and have moderate-to-severe or severe secondary (or functional) MR with a left ventricular ejection fraction (LVEF) of 20-50%, and a left ventricular end-systolic dimension (LVESD) ≤70 mm10. Interventions on complex primary MR currently remain under the surgical domain, although several trials (MITRA high risk (HR) and REPAIR) are underway to evaluate the role of transcatheter mitral valve repair in high to intermediate surgical risk patients with primary MR.
The ACC/AHA noted that transcatheter mitral repair is only recommended for high-risk patients. With regards to secondary MR, ‘guideline-directed medical therapy supervised by a heart failure specialist’ is recommended. Mitral valve surgery is still considered the ideal option for patients with normal left ventricular ejection fraction. The guidelines state that transcatheter mitral repair ‘can be considered’ if LVEF is between 20-50% and other persistent symptoms are present3.
- Mack MJ, Leon MB, Thourani VH, et al. Transcatheter Aortic-Valve Replacement with a Balloon-Expandable Valve in Low-Risk Patients. N Engl J Med 2019;380:1695-705. 10.1056/NEJMoa1814052
- Popma JJ, Deeb GM, Yakubov SJ, et al. Transcatheter Aortic-Valve Replacement with a Self-Expanding Valve in Low-Risk Patients. N Engl J Med 2019;380:1706-15. 10.1056/NEJMoa1816885
- Otto CM, Nishimura RA, Bonow RO, Carabello BA, Erwin III JP, Gentile F, Jneid H, Krieger EV, Mack M, McLeod C, O’Gara PT. 2020 ACC/AHA guideline for the management of patients with valvular heart disease: a report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines. Journal of the American College of Cardiology. 2021 Feb 2;77(4):e25-197.
- Testa L, Popolo Rubbio A, Casenghi M, et al. Transcatheter mitral valve replacement in the transcatheter aortic valve replacement era. J Am Heart Assoc 2019; 8:e013352.
- Nishimura RA, Vahanian A, Eleid MF, Mack MJ. Mitral valve disease—current management and future challenges. Lancet 2016; 387:1324–1334.
- Wu S, Chai A, Arimie S, et al. Incidence and treatment of severe primary mitral regurgitation in contemporary clinical practice. Cardiovasc Revasc Med 2018; 19:960–963.
- Mirabel M, Iung B, Baron G, et al. What are the characteristics of patients with severe, symptomatic, mitral regurgitation who are denied surgery? Eur Heart J 2007; 28:1358–1365.
- Stone GW, Lindenfeld J, Abraham WT, et al. Transcatheter mitral-valve repair in patients with heart failure. N Engl J Med 2018; 379:2307–2318.
- Obadia J, Messika-Zeitoun D, Leurent G, et al. Percutaneous repair or medical treatment for secondary mitral regurgitation. N Engl J Med 2018; 379:2297–2306.
- 2020 FDA approves new indication for valve repair device to treat certain heart failure patients with mitral regurgitation. https://www.fda.gov/news-events/press-announcements/fda-approves-new-indication-valve-repair-device-treat-certain-heart-failure-patients-mitral. [Accessed Feb 2021]
- Kang JJ, Bozso SJ, El-Andari R, Adams C, Nagendran J. Transcatheter mitral valve repair and replacement: the next frontier of transcatheter valve intervention. Current Opinion in Cardiology. 2021 Mar 1;36(2):163-71.