Tricuspid regurgitation may result from structural alterations of any or all of the components of the tricuspid valve apparatus (see Anatomy). The lesion may be classified as primary when it is caused by an intrinsic abnormality of the valve apparatus or as secondary when it is caused by right ventricular (RV) dilatation or other conditions (eg, left ventricular [LV] dysfunction).
Common presenting complaints in patients with RV dysfunction include the following (see Presentation):
Color flow Doppler echocardiography is a mainstay for evaluating tricuspid regurgitation (see Workup). Depending on the etiology and severity of tricuspid regurgitation, treatment may involve medication or surgical repair or replacement of the valve. (See Treatment and Medication.)
See also Tricuspid Atresia and Tricuspid Stenosis.
The right atrioventricular valve complex (the tricuspid valve) comprises the following:
The coordinated actions of the tricuspid valve are made possible by the atrial and ventricular masses, conduction system tissue, and support structure of the fibroelastic cardiac skeleton.
Pathophysiologic variants include the following:
See Tricuspid Valve Anatomy for further details.
The pathophysiology of tricuspid regurgitation focuses on the structural incompetence of the valve. The incompetence can result from primary structural abnormalities of the leaflets and chordae or, more often, be secondary to myocardial dysfunction and dilatation.[1]
Tricuspid valve insufficiency due to leaflet abnormalities may be secondary to endocarditis or rheumatic heart disease. When due to the latter, it generally occurs in combination with tricuspid stenosis. Ebstein anomaly is the most common congenital form of tricuspid regurgitation.
Inspiration increases the severity of tricuspid regurgitation. Inspiration induces widening of the RV, which enlarges the tricuspid valve annulus and thus increases the effective regurgitant orifice area.[2]
Chronically, tricuspid regurgitation leads to RV volume overload, which results in right-sided congestive heart failure (CHF). This manifests as hepatic congestion, peripheral edema, and ascites.
Pure tricuspid regurgitation can be caused by at least 10 conditions, as follows:
Tricuspid regurgitation secondary to rheumatic involvement is usually associated with mitral and aortic valve pathology.[1] The valve develops diffuse fibrous thickening without commisural fusion, fused chordae, or calcific deposits. Occasionally, the chordae may be mildly thickened by fibrous tissue. Rheumatic disease is the most common cause of pure tricuspid regurgitation due to deformation of the leaflets.
Endocarditis is an important cause of tricuspid regurgitation. Factors that can contribute to infection of the valve include alcoholism, intravenous drug use, neoplasms, infected indwelling catheters, extensive burns, and immune deficiency. The clinical presentation is often that of pneumonia from septic pulmonary emboli rather than CHF. Heart murmurs are frequently absent and blood cultures may be negative. Annular abscesses are not uncommon.
Ebstein anomaly is a congenital malformation of the tricuspid valve characterized by apical displacement of the annular insertion of the septal and posterior leaflets and atrialization of a portion of the ventricular myocardium. Prognosis for these patients depends upon the degree of apical displacement of the tricuspid annulus and the severity of the regurgitation.[3]
The incidence of tricuspid valve prolapse (floppy tricuspid valve) varies from 0.3-3.2%. The lesion appears to be associated with prolapse of the mitral valve; uncommonly, it occurs in an isolated fashion. Histological examination of the floppy tricuspid valve shows alterations on the valve spongiosa.
Pure tricuspid regurgitation can occur as part of the carcinoid heart syndrome. Fibrous white plaques form on the ventricular aspect of the tricuspid valve and endocardium, causing the valve to adhere to the RV wall. Proper coaptation of the leaflets does not occur during systole, resulting in tricuspid regurgitation.[4]
Papillary muscle dysfunction may result from necrosis secondary to myocardial infarction, fibrosis, or infiltrative processes. Although dysfunction secondary to myocardial infarction is less common than occurs with the mitral valve, the underlying cause must be determined in order to plan treatment.
Trauma to the RV may damage the structures of the tricuspid valve, resulting in insufficiency of the structure.[5] Stab wounds and projectiles are the most common sources of trauma in these cases.
Marfan syndrome or other connective-tissue diseases (eg, osteogenesis imperfecta, Ehlers-Danlos syndrome) may cause tricuspid regurgitation. Dysfunction of other heart valves is typically present, as well. The tricuspid regurgitation can be attributed to a floppy tricuspid valve and a mildly dilated tricuspid valve annulus.
Medications that act via serotoninergic pathways may cause valvular lesions similar to those observed with carcinoid. Medications used to treat migraine (eg, methysergide), Parkinson disease (eg, pergolide), and obesity (eg, fenfluramine) have been associated with tricuspid regurgitation.
In persons with an anatomically normal tricuspid valve, a common etiology of tricuspid regurgitation is dilatation of the RV cavity. The valve structures are normal; however, because of enlargement of the cavity and dilatation of the annulus, the leaflets cannot coapt properly. The following disorders can cause RV dilatation:
The incidence of tricuspid regurgitation in the United States appears to be 0.9%. Internationally, the incidence of tricuspid regurgitation also appears to be less than 1%. No racial or sexual differences in incidence are apparent.
Age at presentation varies with the etiology of tricuspid regurgitation. Ebstein anomaly can be detected at birth and during early childhood. In patients older than 15 years, the most common form of tricuspid regurgitation is rheumatic valvular disease. In the adult population, other predisposing factors take precedence; these include carcinoid, bacterial endocarditis, and heart failure.
The prognosis in patients with tricuspid regurgitation is generally good. If the cause of the regurgitation is infection, removal of the valve generally cures the problem, provided that the source of the infection (eg, poor dentition, illicit drug use) is eliminated. For patients with accompanying pulmonary hypertension or cardiac dilatation, the prognosis is directly related to the prognosis for those conditions.
Complications of tricuspid regurgitation include cardiac cirrhosis, ascites, thrombus formation, and embolization. Possible complications of operative intervention include heart block, arrhythmias, thrombosis of the prosthetic valve, and infection.
The morbidity and mortality associated with tricuspid regurgitation vary with the underlying cause. In rheumatic disease, mortality rates with treatment are less than 3%. In Ebstein anomaly, mortality depends upon the severity of the valvular deformity and the feasibility of correction. Tricuspid regurgitation resulting from myocardial dysfunction or dilatation has a mortality of up to 50% at 5 years.
Mortality rates with correction are approximately 10%. Tricuspid valve replacement for severe tricuspid regurgitation can be performed with an acceptable operative mortality if patients undergo surgery before the onset of advanced heart failure symptoms.[6]
Patients with tricuspid regurgitation present with the signs and symptoms of right-sided heart failure. The spectrum of presenting symptoms depends on whether the condition is secondary to right ventricular (RV) dilatation or other conditions (eg, left ventricular [LV] dysfunction).
Common presenting complaints in patients with RV dysfunction include the following:
Exercise intolerance may also be observed. Rarely, patients report angina, which may result from RV overload and strain, even in the absence of coronary artery disease.[7]
These patients, especially those experiencing febrile episodes, must be questioned regarding risk factors for infective endocarditis , which is a common cause of tricuspid valvular disease. Risk factors include intravenous drug use, alcoholism, and a history of rheumatic fever.
Findings on cardiovascular examination in patients with tricuspid regurgitation include the following:
The pansystolic murmur associated with tricuspid regurgitation is high pitched and is loudest in the fourth intercostal space in the parasternal region. The murmur is usually augmented during inspiration and is reduced in intensity and duration in the standing position and during a Valsalva maneuver. A short, early diastolic flow rumble may be present due to increased flow across the tricuspid valve.
Color flow Doppler echocardiography is a mainstay for evaluating tricuspid regurgitation. The following studies are also used in the workup:
ECG findings are usually nonspecific. Typical abnormalities are incomplete right bundle-branch block, Q waves in lead V1, and atrial fibrillation.
On cardiac catheterization, right atrial pressure and right ventricular end-diastolic pressure are elevated. A rise or no change in right atrial pressure on deep inspiration is characteristic of tricuspid regurgitation. The use of angiography in this setting is controversial.
Findings on chest radiography in patients with tricuspid regurgitation include the following:
Color flow Doppler echocardiography is a mainstay for evaluating tricuspid regurgitation. Doppler techniques are used to directly visualize regurgitant jets, measure the flow velocities of the regurgitant jets, and accurately estimate right ventricular systolic pressure. See Tricuspid Valve Disease Imaging.
In trivial-to-mild tricuspid regurgitation, the jet is central and narrow. In moderate-to-severe pulmonic regurgitation, the width of the jet increases, as does the penetration of the jet into the right atrium.
European Society of Cardiology (ESC)/European Association for Cardio-Thoracic Surgery (EACTS) echocardiographic criteria for severe tricuspid regurgitation include the following[8] :
Other possible findings on echocardiography include the following:
Using pulsed wave and continuous wave Doppler, right ventricular and pulmonary arterial systolic pressure can be estimated (using continuous wave Doppler) by measuring the peak regurgitant flow velocity across the tricuspid valve, converting it to a pressure gradient (by use of the modified Bernoulli equation), and then adding the gradient to an estimate of the right atrial pressure.[9, 10, 11]
Yang and colleagues proposed that quantification of tricuspid regurgitation by Doppler echocardiography is crucial for estimating prognosis. Their study in patients with severe isolated tricuspid regurgitation found that vena contracta width (VCW) of more than 7 mm is a powerful independent predictor of worsening heart failure, tricuspid valve surgery, and cardiovascular death.[12]
The choice of treatment for tricuspid regurgitation depends on the etiology and severity of the condition. Medical therapy may be used in tricuspid regurgitation secondary to left-sided heart failure. With mild tricuspid regurgitation associated with mitral valve disease and pulmonary hypertension, the tricuspid regurgitation itself does not require intervention. As pulmonary vascular pressures fall with successful mitral valve therapy, the tricuspid regurgitation tends to disappear.
Surgical options include annuloplasty and valve replacement. Indications for surgical intervention include the following:
In a recent study, investigators evaluated a novel transcatheter repair system for the treatment of severe tricuspid regurgitation. They treated seven high-risk patients with severe tricuspid regurgitation and clinical signs of heart failure, who were declined for surgery, with the transcatheter repair system. All patients showed improvements in the severity of tricuspid regurgitation, as well as improvements in peripheral edema and functional status.[13]
For patients in whom tricuspid regurgitation is secondary to left-sided heart failure, treatment centers on adequate control of fluid overload and failure symptoms (eg, diuretic therapy). Patients should be instructed to reduce their intake of salt. Elevation of the head of the bed may improve symptoms of shortness of breath.
Digitalis, diuretics (including potassium-sparing agents), angiotensin-converting enzyme (ACE) inhibitors, and anticoagulants are all indicated in the care of these patients. Antiarrhythmics are added as needed to control atrial fibrillation.
The need for correction of tricuspid regurgitation is usually considered at the time of surgical correction of left-sided valve lesions. Severe regurgitation has been successfully treated with tricuspid annuloplasty. Long-term results with prosthetic rings are superior to those achieved with suture annuloplasty.[8]
In patients with organic disease of the tricuspid valve, corrective measures usually involve valve replacement. Because of the increased incidence of mechanical prosthetic valve thrombosis in this low-flow position, a bioprosthetic valve is preferable.
In patients with tricuspid valve endocarditis, total excision of the tricuspid valve without immediate replacement is recommended. The diseased valvular tissue is excised to eradicate the endocarditis, and antibiotic treatment is continued. Most patients tolerate loss of the tricuspid valve well for years. If right heart failure symptoms persist despite medical management and the infections have been controlled, an artificial valve can be inserted.
In patients with Ebstein anomaly, asymptomatic tricuspid regurgitation does not require surgery. If this anomaly produces symptomatic tricuspid regurgitation, then tricuspid valve repair or replacement is indicated.[1, 14, 15, 16, 17]
Ibrahim et al found evidence that cone reconstruction of severe tricuspid valve regurgitation associated with Ebstein’s anomaly provides effective repair. In their analysis of 27 consecutive cone reconstructions undertaken from 2009 to 2013, they found that patients’ clinical status improved with better left ventricle filling and objective exercise capacity.[18]
In selected cases, patients who have undergone prior tricuspid valve surgery may be candidates for percutaneous tricuspid valve replacement.[19] Indications for this procedure include significant stenosis and/or regurgitation of a bioprosthetic tricuspid valve or a right atrium–to–right ventricle (RA-to-RV) conduit.
Inpatient care of patients with tricuspid regurgitation requires control of the following:
Anticoagulation is generally in order if atrial fibrillation is present or valve replacement has been undertaken. The international normalized ratio (INR) should be maintained between 3-4 following valve replacement, because of the associated low flow state.
Patients with a history of tricuspid regurgitation should be carefully monitored for control of any heart failure. Repeat echocardiography is indicated at 6-month intervals for patients in whom the valve has been removed. Annual echocardiography should be considered in patients whose valve has been replaced.
In 2014, the AHA/ACC released a revision to its 2008 guidelines for management of patients with valvular heart disease (VHD)[20] ; and ESC/EACTS issued a revision of its 2007 guidelines in 2012.[8]
The AHA/ACC guidelines classify progression of tricuspid regurgitation (TR) into 4 stages (A to D) as follows[20] :
Both guidelines require intervention decisions for severe valvular heart disease (VHD) should be based on an individual risk-benefit analysis. Improved prognosis should outweigh the risk of intervention and potential late consequences, particularly complications related to prosthetic valves.[8, 20]
Recognizing the known limitations of the EuroSCORE (European System for Cardiac Operative Risk Evaluation) and the STS (Society of Thoracic Surgeons) score , the AHA/ACC guidelines suggest using STS plus three additional indicators: frailty (using accepted indices), major organ system compromise not to be improved postoperatively, and procedure-specific impediment when assessing risk.[20]
The AHA/ACC guidelines include the following recommendations for diagnostic testing and initial diagnosis of TR[20] :
A comparison of the recommendations for surgical intervention is provided in the table below.
Table. Comparison of Recommendations for tricuspid valve disease Intervention
View Table | See Table |
The medical therapy used in the treatment of tricuspid regurgitation is directed toward the control of heart failure that is causing or contributing to the problem. Drugs used include diuretics, digoxin, and angiotensin-converting enzyme (ACE) inhibitors. Patients who have atrial fibrillation or who have received a prosthetic valve require anticoagulation.
Clinical Context: Furosemide (Lasix)
Furosemide increases excretion of water by interfering with the chloride-binding cotransport system, which in turn inhibits sodium and chloride reabsorption in the ascending loop of Henle and distal renal tubule. The dose must be individualized to the patient. Depending on response, administer at increments of 20-40 mg, no sooner than 6-8 h after the previous dose, until desired diuresis occurs. When treating infants, titrate with 1 mg/kg/dose increments until a satisfactory effect is achieved.
Diuretics are used to control the fluid overload associated with tricuspid regurgitation.
Clinical Context: Digoxin (Lanoxin, Digox)
Digoxin is a cardiac glycoside with direct inotropic effects in addition to indirect effects on the cardiovascular system. This agent acts directly on cardiac muscle, increasing myocardial systolic contractions. Its indirect actions result in increased carotid sinus nerve activity and enhanced sympathetic withdrawal for any given increase in mean arterial pressure.
These drugs (primarily digoxin) are used to control atrial fibrillation and to increase myocardial contractility.
Clinical Context: Captopril prevents conversion of angiotensin I to angiotensin II, a potent vasoconstrictor, resulting in increased levels of plasma renin and a reduction in aldosterone secretion.
Clinical Context: Enalapril is a competitive ACE inhibitor that reduces angiotensin II levels and decreases aldosterone secretion.
Clinical Context: Lisinopril prevents conversion of angiotensin I to angiotensin II, resulting in decreased aldosterone secretion.
ACE inhibitors are used to provide afterload reduction, thereby decreasing the volume load on the right ventricle.
Clinical Context: Warfarin interferes with hepatic synthesis of vitamin K–dependent coagulation factors. It is used for prophylaxis and treatment of venous thrombosis, pulmonary embolism, and thromboembolic disorders. Tailor the dose to maintain an international normalized ratio (INR) in the range of 2-3.
In patients who have undergone valve replacement for treatment of severe tricuspid regurgitation, anticoagulants are used to prevent thrombosis and embolization from the prosthetic valve.
Recommendation AHA/ACC (2014)[20] ESC/EACTS (2012)[8] Tricuspid valve surgery for patients with severe tricuspid regurgitation(TR) or severe tricuspid stenosis (TS) when undergoing left-sided valve surgery Class I Class I Tricuspid valve surgery for patients with isolated, symptomatic severe TS. Class I Class I Tricuspid valve surgery for patients with isolated, symptomatic severeTR without severe right ventricle dysfunction Class I Tricuspid valve repair for patients with mild, moderate, or greater functional TR (stage B) at the time of left-sided valve surgery with either 1) tricuspid annular dilation or 2) prior evidence of right HF Class IIa-Reasonable Class IIa-Reasonable Tricuspid valve surgery for patients with symptoms due to severe primary TR that are unresponsive to medical therapy (stage D). Class IIa-Reasonable After left-sided valve surgery, surgery for patients with severe TR who are symptomatic or have progressive right ventricular dilatation/dysfunction, in the absence of left-sided valve dysfunction,
severe right or left ventricular dysfunction, and severe pulmonary vascular diseaseClass IIa-Reasonable Tricuspid valve repair for patients with moderate functional TR (stage B) and pulmonary artery hypertension at the time of left-sided valve surgery Class IIb-Consider Tricuspid valve surgery for asymptomatic or minimally symptomatic patients with severe primary TR (stage C) and progressive degrees of moderate or greater RV dilation and/or systolic dysfunction. Class IIb-Consider Class IIa-Reasonable Reoperation for isolated tricuspid valve repair or replacement for persistent symptoms due to severe TR (stage D) in patients who have undergone previous left-sided valve surgery and who do not have severe pulmonary hypertension or significant RV systolic dysfunction. Class IIb-Consider Percutaneous balloon tricuspid commissurotomy in patients with isolated, symptomatic severe TS without accompanying TR. Class IIb-Consider