TRICUSPID REGURGITATION (TR)
TR can be classified into Primary or Secondary (Functional) TR.
3
PRIMARY TR
Rheumatic
Infective endocarditis
Iatrogenic (i.e., device leads)
Congenital
Other Causes (i.e., trauma, carcinoid, or drug use)
SECONDARY (FUNCTIONAL) TR
Pulmonary hypertension
with RV remodeling
Dilated
cardiomyopathy
Annular dilation
RV volume overload
FUNCTIONAL TR
FUNCTIONAL TR IS A DISORDER WHICH AFFECTS THE TRICUSPID VALVE OF THE HEART.
The blood that flows between the different chambers of the heart must pass through valves (1,3,5).These valves open just enough to allow blood to flow through the chambers then close again to keep blood from flowing backward. The tricuspid valve (3) separates the right lower heart chamber—the right ventricle (4) from the right upper heart chamber—the right atrium (2).
Tricuspid regurgitation (TR) is a disorder in which this valve does not close tightly enough. TR is a complex disease with several independent causes, which if left untreated can progress to severe right ventricular (RV) dysfunction leading to RV failure and episodes of recurrent heart failure. In a heart with functional tricuspid regurgitation, the valve is not able to close completely, which means oxygen-deficient blood flows back into the atrium. TR causes reduced blood flow into the lungs, which results in symptoms such as fatigue, shortness of breath, and swelling of the legs and/or abdomen.
1
2
3
4
5
~70%
OF PATIENTS DIAGNOSED WITH SEVERE TR
DIE WITHIN 5 YEARS
2
MORBIDITY & MORTALITY
TRICUSPID REGURGITATION IS DEADLY
It is believed that 90% of TR is due to annular dilation. Less than 1% of an estimated 1.6 million people in the US suffering from TR are treated. Right-sided heart surgery is associated with mortality and morbidity far greater than left-sided surgery, and progressive right-sided heart failure/RV dysfunction can lead to significant morbidity for patients.
In comparison with the aortic and mitral valves, the tricuspid valve is best suited for transcatheter therapy.
4,5
6
1
Graph 1: The Kaplan-Meier survival curves of all patients according to TR grade.
UNDERTREATMENT OF FUNCTIONAL TR
Stuge and Liddicoat estimated that in 2006, approximately 1.6 million Americans have moderate to severe TR. However, less than 8,000 patients have been treated due to the complexity of right-sided open-heart surgery.
These estimates do not include the large additional number of patients who may benefit from concomitant treatment of the tricuspid annulus in connection with the treatment of a range of left ventricular diseases.
Patients with severe tricuspid regurgitation
N=1,600,000
.5%
TRICUSPID SURGERY
NO SURGERY
Patients referred for heart valve surgery
N=4,741
1.3%
TRICUSPID SURGERY
OTHER VALVE SURGERY
1. Stuge O, Liddicoat J. Emerging opportunities for cardiac surgeons within structural heart disease. J Thorac Cardio Surg 2006
2. Chorin E, Rozenbaum Z, Topilsky Y, et al. Tricuspid regurgitation and long-term clinical outcomes. European Heart Journal – Cardiovascular Imaging 2019; 21(2):157-65.
3. Otto CM, Nishimura RA, Bonow RO, et al. 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. Circulation. 2021/02/02 2021;143(5):e72-e227. doi:10.1161/CIR.0000000000000923
4. Dreyfus GD, Corbi PJ, Chan KM, Bahrami T. Secondary tricuspid regurgitation or dilatation: which should be the criteria for surgical repair? Ann Thorac Surg 2005;79:127–32.
5. Taramasso M, Vanermen H, Maisano F, Guidotti A, La Canna G, Alfieri O. The growing clinical importance of secondary tricuspid regurgitation. J Am Coll Cardiol 2012;59:703–10.
6. Konstam MA, Keiernan MS, Bernstein D, et al. Evaluation and management of right-sided heart failure: a scientific statement from the American Heart Association, Circulation 2018;137(20): e578–e622
