Very little is known about tricuspid valve when compared to other valvular disorders, and tricuspid stenosis (TS) is even more rarely described. It most often co-exists with mitral valve pathology especially in patients with rheumatic heart disease
Rheumatic heart disease is one of the most common causes of TS and almost always occurs in conjunction with mitral stenosis . Large vegetations in infective endocarditis can cause relative stenosis . Carcinoid syndrome may cause isolated TS or mixed with the regurgitant lesion . Systemic diseases like systemic lupus erythematosus (SLE), antiphospholipid antibody (APLA) syndrome and the presence of permanent pacing and fusion of implantable cardioverter defibrillator leads to sub-valvular structures can cause tricuspid stenosis. Benign tumors like atrial myxomas can cause functional TS . Blunt trauma has also been described as a risk factor. Renal and ovarian tumors can grow into the tricuspid orifice causing stenosis .
Other less common causes of TS include congenital abnormalities (Ebstein’s anomaly), metabolic or enzymatic abnormalities (Fabry’s disease, Whipple’s disease). Sometimes described are intravenous leiomyomatosis, ventriculoatrial shunts  causing TS. Valvulopathy associated with drugs like fenfluramine/phentermine and methysergide is characterized by thickened fibrotic and hypomobile tricuspid leaflets, with various degrees of valve stenosis and regurgitation.
The circumference of the normal tricuspid valve is 12 to 14 cm, and most pathologists consider a circumference of less than 10 to 11 cm (i.e., diameter less than 3 cm or valve area of less than 7 cm^2) as an indication of TS. Normal Area of the tricuspid valve is 4.0 cm2 and area less than 1.0 cm^2 is deemed as severe TS 
The rheumatic tricuspid disease is characterized by diffuse fibrous thickening of the leaflets and fusion of 2 or 3 commissures. Leaflet thickening usually occurs in the absence of calcific deposits, and the anteroseptal commissure is most commonly involved. Incompletely developed leaflets, shortened or malformed chordae, a small annulus, or an abnormal number or size of papillary muscles may result in TS.
The valves consist of an outer layer of valve endothelial cells (VECs) surrounding three layers of the extracellular matrix each with specialized function and interspersed with interstitial valve cells (VICs). Genetic or acquired/environmental causes that disrupt the normal organization and composition of the extracellular matrix and communication between VECs and VICs alter valve mechanics and interfere with the valve leaflet function, culminating in heart failure.
The primary result of TS is right atrial pressure elevation and consequent right-sided congestion.
Presenting symptoms are generally related to right-sided valve disease such as reduced exertional capacity, fatigue, or, exertional syncope. Patients with severe TS will eventually have hepatic congestion, leg edema, ascites, and deterioration of liver function tests and anasarca.
"Giant a waves" classically greater in height than usually perceived in the jugular venous pulse, are seen in TS. A "slow y descent" due to delayed emptying of the right atrium into the right ventricle can also be seen.
The lungs are clear in patients with isolated TS. A low frequency presystolic mid-diastolic murmur is heard at the lower left sternal border in the fourth intercostal space. The intensity of the murmur and opening snap in TS increase with maneuvers that increase blood flow across the tricuspid valve, especially with inspiration and also with leg raising, inhalation of amyl nitrate, squatting, or exercise.
Electrocardiogram: In patients with TS in sinus rhythm, the electrocardiogram may show tall, peaked P waves in leads II, III, and avF consistent with right atrial enlargement.
Echocardiography: Tricuspid peak inflow velocity during inspiration of > 1 m/s, Inflow time-velocity integral greater than 60 cm, valve area by the continuity of less than or equal to 1 cm^2 indicates hemodynamically significant TS.
The mean transvalvular pressure gradient derived using the Bernoulli equation is usually lower in tricuspid stenosis than in mitral stenosis, ranging between 2 and 10 mm Hg, and averaging around 5 mmHg. A mean gradient greater than or equal to 5 mm Hg at normal heart rate is considered indicative of clinically significant TS . Higher gradients may be seen with combined stenosis and regurgitation. A longer T 1/2 (pressure halftime by continuous wave Doppler) implies a greater TS severity with values of greater than or equal to 190 ms being frequently associated with significant (or critical) stenosis. Other parameters that are seen include- reduced TAPSE, dilated IVC, and increased right atrial size.
Cardiac Catheterization: In TS, there is a large right atrial "a" wave of 12 to 20 mm Hg and a diastolic, mean gradient of 4 to 8 mm Hg across the tricuspid valve. The mean gradient across the tricuspid valve is more significant in tricuspid stenosis because an end-diastolic gradient may be absent with significant obstruction. This is because of the lower filling pressures on the right side of the heart. Elevated RA pressure with a slow fall in early diastole and a diastolic pressure gradient across the tricuspid valve is characteristic of TS.
Cardiac MRI: Cardiac MRI is now the preferred method to evaluate RV size and function.
Loop diuretics may be useful to relieve systemic and hepatic congestion in patients with severe, symptomatic TS . Caution is advised since diuretics may decrease the preload further in patients who have low output state.
Not every TS needs invasive intervention. Treatment of SLE and APLA syndrome may reduce the “coating” over the valves and chordae and reduce stenosis and regurgitation. Cessation of fenfluramine or methysergide has been associated with valve normalization. Less often, surgical therapy may be needed in addition to medical management.
A decision should be made to treat the patient with a valvotomy or valve surgery.
Valvotomy: Valvotomy is performed using 1, 2, or 3 balloons. While some stenosis may persist, the change in valve area causes a significant reduction in the transvalvular pressure gradient and a decrease in right atrial pressure.
Valve surgery: Tricuspid valve surgery includes repair vs. replacement. Repair should be attempted when reasonable. When repair is not an option, valve replacement can be done by open versus transcatheter replacement. While replacing the valve, no differences in outcomes have been established between bioprosthetic vs. mechanical valves. However, in carcinoid syndrome, a mechanical valve is preferred over bioprosthetic to avoid degeneration.
Surgery for severe TS is most often performed at the time of operation for left-sided valve disease, chiefly rheumatic mitral stenosis/mitral replacement. Tricuspid valve surgery is preferred over percutaneous balloon tricuspid commissurotomy for treatment of symptomatic severe TS because most cases of severe TS are accompanied with tricuspid regurgitation (TR) (rheumatic, carcinoid), and percutaneous balloon tricuspid commissurotomy may either create or worsen regurgitation.
Isolated, symptomatic severe TS without accompanying TR is an extremely rare condition for which percutaneous balloon tricuspid commissurotomy might be considered. Valve areas generally increase from less than 1 to almost 2 cm. It is also an option for patients considered to be at high surgical risk. Percutaneous balloon valvuloplasty may be done in non-surgical cases.
There is very limited information comparing percutaneous balloon valvotomy with tricuspid valve surgery.
Bioprosthetic valve stenosis can be treated with balloon valvotomy or valve-in-valve replacement.
TS staging sections into categories A, B, C, D. Stages C (without symptoms) and D (with symptoms). When valve and/or chordal thickening and calcification are evident, there are additional findings indicative of severe TS, for example, pressure gradient greater than or equal to 5 mm Hg, pressure half-time greater than or equal to 190 milliseconds, valve area less than or equal to 1.0 cm^2, associated moderate right atrial enlargement, and inferior vena cava dilatation.
Tricuspid valve stenosis is a rare disorder and best managed by an interprofessional team. In most cases, mild cases of tricuspid stenosis are well tolerated and can be managed medically. Severe cases may require surgery. While dilatation of the leaflets can be undertaken, recurrence is common. In most cases, the valve may need to be replaced. The outcomes for tricuspid stenosis depend on the cause.
|||Some observations on mitral and aortic valve disease., Roberts WC,Ko JM,, Proceedings (Baylor University. Medical Center), 2008 Jul [PubMed PMID: 18628928]|
|||Pathology of tricuspid valve stenosis and pure tricuspid regurgitation--Part I., Waller BF,Howard J,Fess S,, Clinical cardiology, 1995 Feb [PubMed PMID: 7720297]|
|||Carcinoid heart disease. Clinical and echocardiographic spectrum in 74 patients., Pellikka PA,Tajik AJ,Khandheria BK,Seward JB,Callahan JA,Pitot HC,Kvols LK,, Circulation, 1993 Apr [PubMed PMID: 7681733]|
|||Isolated tricuspid valve repair for Libman-Sacks endocarditis., Gur AK,Odabasi D,Kunt AG,Kunt AS,, Echocardiography (Mount Kisco, N.Y.), 2014 Jul [PubMed PMID: 24661289]|
|||The Forgotten Valve: Isolated Severe Tricuspid Valve Stenosis., Al-Hijji M,Yoon Park J,El Sabbagh A,Amin M,Maleszewski JJ,Borgeson DD,, Circulation, 2015 Aug 18 [PubMed PMID: 26283605]|
|||Right atrial myxoma mimicking tricuspid stenosis., Şaşkın H,Düzyol Ç,Özcan KS,Aksoy R,, BMJ case reports, 2015 Aug 13 [PubMed PMID: 26272962]|
|||Seibert KA,Rettenmier CW,Waller BF,Battle WE,Levine AS,Roberts WC, Osteogenic sarcoma metastatic to the heart. The American journal of medicine. 1982 Jul; [PubMed PMID: 6953763]|
|||Khatib N,Blumenfeld Z,Bronshtein M, Early prenatal diagnosis of tricuspid stenosis. American journal of obstetrics and gynecology. 2012 Nov; [PubMed PMID: 22964066]|
|||Tricuspid stenosis due to intravenous leiomyomatosis--a call for caution: case report and review of the literature., Nili M,Liban E,Levy MJ,, Texas Heart Institute journal, 1982 Jun [PubMed PMID: 15226964]|
|||Akram Q,Saravanan D,Levy R, Valvuloplasty for tricuspid stenosis caused by a ventriculoatrial shunt. Catheterization and cardiovascular interventions : official journal of the Society for Cardiac Angiography [PubMed PMID: 20824751]|
|||Evaluation of tricuspid valve morphology and function by transthoracic three-dimensional echocardiography., Muraru D,Badano LP,Sarais C,Soldà E,Iliceto S,, Current cardiology reports, 2011 Jun [PubMed PMID: 21365261]|
|||Tao G,Kotick JD,Lincoln J, Heart valve development, maintenance, and disease: the role of endothelial cells. Current topics in developmental biology. 2012; [PubMed PMID: 22449845]|
|||Long-term follow-up of patients with severe rheumatic tricuspid stenosis., Roguin A,Rinkevich D,Milo S,Markiewicz W,Reisner SA,, American heart journal, 1998 Jul [PubMed PMID: 9665226]|
|||KITCHIN A,TURNER R, DIAGNOSIS AND TREATMENT OF TRICUSPID STENOSIS. British heart journal. 1964 May; [PubMed PMID: 14156086]|
|||Bonow RO,Carabello BA,Chatterjee K,de Leon AC Jr,Faxon DP,Freed MD,Gaasch WH,Lytle BW,Nishimura RA,O'Gara PT,O'Rourke RA,Otto CM,Shah PM,Shanewise JS, 2008 Focused update incorporated into the ACC/AHA 2006 guidelines for the management of patients with valvular heart disease: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Revise the 1998 Guidelines for the Management of Patients With Valvular Heart Disease): endorsed by the Society of Cardiovascular Anesthesiologists, Society for Cardiovascular Angiography and Interventions, and Society of Thoracic Surgeons. Circulation. 2008 Oct 7; [PubMed PMID: 18820172]|
|||Extracellular matrix remodeling and organization in developing and diseased aortic valves., Hinton RB Jr,Lincoln J,Deutsch GH,Osinska H,Manning PB,Benson DW,Yutzey KE,, Circulation research, 2006 Jun 9 [PubMed PMID: 16645142]|
|||Right-sided valve disease., Coffey S,Rayner J,Newton J,Prendergast BD,, International journal of clinical practice, 2014 Oct [PubMed PMID: 25269950]|
|||Natural history of chronic valvular disease., Stapleton JF,, Cardiovascular clinics, 1986 [PubMed PMID: 3742519]|
|||Applefeld MM, The Jugular Venous Pressure and Pulse Contour 1990; [PubMed PMID: 21250143]|
|||Isolated tricuspid stenosis., Morgan JR,Forker AD,Coates JR,Myers WS,, Circulation, 1971 Oct [PubMed PMID: 5094152]|
|||Echocardiographic assessment of valve stenosis: EAE/ASE recommendations for clinical practice., Baumgartner H,Hung J,Bermejo J,Chambers JB,Evangelista A,Griffin BP,Iung B,Otto CM,Pellikka PA,Quiñones M,, Journal of the American Society of Echocardiography : official publication of the American Society of Echocardiography, 2009 Jan [PubMed PMID: 19130998]|
|||Doppler echocardiography in the evaluation of tricuspid stenosis., Fawzy ME,Mercer EN,Dunn B,al-Amri M,Andaya W,, European heart journal, 1989 Nov [PubMed PMID: 2591399]|
|||Appetite suppressants and valvular heart disease., Seghatol FF,Rigolin VH,, Current opinion in cardiology, 2002 Sep [PubMed PMID: 12357124]|
|||Nishimura RA,Otto CM,Bonow RO,Carabello BA,Erwin JP 3rd,Guyton RA,O'Gara PT,Ruiz CE,Skubas NJ,Sorajja P,Sundt TM 3rd,Thomas JD, 2014 AHA/ACC guideline for the management of patients with valvular heart disease: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines. Journal of the American College of Cardiology. 2014 Jun 10; [PubMed PMID: 24603191]|
|||Non-functional tricuspid valve disease., Adler DS,, Annals of cardiothoracic surgery, 2017 May [PubMed PMID: 28706863]|
|||Initial outcome of percutaneous balloon valvuloplasty in rheumatic tricuspid valve stenosis., Orbe LC,Sobrino N,Arcas R,Peinado R,Frutos A,Blazquez JR,Maté I,Sobrino JA,, The American journal of cardiology, 1993 Feb 1 [PubMed PMID: 8427185]|
|||Kunadian B,Vijayalakshmi K,Balasubramanian S,Dunning J, Should the tricuspid valve be replaced with a mechanical or biological valve? Interactive cardiovascular and thoracic surgery. 2007 Aug; [PubMed PMID: 17669933]|
|||Surgical management of tricuspid stenosis., Cevasco M,Shekar PS,, Annals of cardiothoracic surgery, 2017 May [PubMed PMID: 28706872]|
|||Ribeiro PA,Al Zaibag M,Al Kasab S,Idris M,Halim M,Abdullah M,Shahed M, Percutaneous double balloon valvotomy for rheumatic tricuspid stenosis. The American journal of cardiology. 1988 Mar 1; [PubMed PMID: 3344697]|
|||McGinn JS,Zipes DP, Constrictive pericarditis causing tricuspid stenosis. Archives of internal medicine. 1972 Mar; [PubMed PMID: 4259627]|