Tricuspid regurgitation | |
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Other names | Tricuspid insufficiency |
Echocardiogram showing typical findings in severe tricuspid regurgitation | |
Specialty | Cardiology |
Symptoms | Ascites [1] |
Causes | Abnormally high blood pressure , other heart problem [2] |
Diagnostic method | Echocardiogram [2] |
Treatment | Diuretic, Surgery [2] |
Tricuspid regurgitation (TR), also called tricuspid insufficiency, is a type of valvular heart disease in which the tricuspid valve of the heart, located between the right atrium and right ventricle, does not close completely when the right ventricle contracts (systole). TR allows the blood to flow backwards from the right ventricle to the right atrium, which increases the volume and pressure of the blood both in the right atrium and the right ventricle, [2] which may increase central venous volume and pressure if the backward flow is sufficiently severe.
The causes of TR are divided into hereditary and acquired; and also primary and secondary. Primary TR refers to a defect solely in the tricuspid valve, such as infective endocarditis; secondary TR refers to a defect in the valve as a consequence of some other pathology, such as left ventricular failure or pulmonary hypertension. [3]
The mechanism of TR is either a dilatation of the base (annulus) of the valve due to right ventricular dilatation, which results in the three leaflets being too far apart to reach one another; or an abnormality of one or more of the three leaflets. [1]
The symptoms of TR depend on its severity. Severe TR causes right-sided heart failure, with the development of ascites and peripheral edema. [1] In severe cases of right heart failure due to TR, venous congestion of the kidneys and liver may lead to cardiorenal syndrome (kidney failure secondary to heart failure) and cardiohepatic syndromes (liver failure secondary to heart failure) respectively. [3] Venous congestion from TR and right heart failure may also lead to anasarca (diffuse swelling) and decreased intestinal absorption due to the swelling surrounding the intestines, in severe cases this may lead to cachexia and malnutrition. [3]
A pansystolic heart murmur may be heard on auscultation of the chest. The murmur is usually of low frequency and best heard on the lower left sternal border. It increases with inspiration, and decreases with expiration: this is known as Carvallo's sign. However, the murmur may be inaudible due to the relatively low pressures in the right side of the heart. A third heart sound may also be present, also heard at the lower sternal border, and increasing in intensity with inspiration. [4] [5]
On examination of the neck, there may be giant C-V waves in the jugular pulse. [6] With severe TR, there may be an enlarged liver detected on palpation of the right upper quadrant of the abdomen; the liver may be pulsatile on palpation and even on inspection. [7]
The causes of TR may be classified as congenital [8] or acquired; another classification divides the causes into primary or secondary. Congenital abnormalities are much less common than acquired. The most common acquired TR is due to right ventricular dilatation. Such dilatation is most often due left heart failure or pulmonary hypertension. Other causes of right ventricular dilatation include right ventricular infarction, inferior myocardial infarction, and cor pulmonale. [3]
In regards to primary and secondary causes they are: [9]
In terms of the mechanism of tricuspid insufficiency, it involves the expansion of the tricuspid annulus (fibrous rings of heart). Tricuspid insufficiency is linked to geometric changes of the tricuspid annulus (decreased tricuspid annular release). The leaflets shape are normal but prevented from normal working mechanism due to a distortion of spatial relationships of leaflets and chords. [10] It is also contemplated that the process via which tricuspid regurgitation emerges, is a decrease of contraction of the myocardium around the annulus. [11]
The diagnosis of TR may be suspected if the typical murmur of TR is heard or other signs suggestive of right heart failure.[ citation needed ]
Definitive diagnosis is made by echocardiogram, which is capable of measuring both the presence and the severity of the TR, as well as right ventricular dimensions and systolic pressures. [12] Cardiac MRI or CT scan may also aid in the diagnosis of TR. [3] On imaging studies, a regurgitant volume greater than 45 milliliters or greater than 50% regurgitation across the tricuspid valve is associated with poor outcomes. [3]
Medical therapy for tricuspid regurgitation consists of diuretics (loop diuretics as the first line therapy with mineralocorticoid receptor antagonists added on for worsening or refractory cases). However, as the disease progresses, diuretics may become inefficient. [13] Diuretic resistance in TR and right heart failure is thought to develop due to a variety of mechanisms working synergistically to lead to decreased effectiveness of diuretics. Decreased effective circulating volume, ie. decreased blood perfusing the kidneys, leads to activation of the renin–angiotensin–aldosterone system, which leads to the kidneys reabsorbing salt and water and vasoconstriction of the arterioles. [3] Intestinal edema may also lead to decreased gut absorption of the diuretics and increased fluid retention may lead to an increased volume of distribution of the diuretic. [3] All of the preceding mechanisms in TR with right heart failure (and sometimes secondary left heart failure) lead to diuretic resistance. Diuretic resistance is associated with a poor prognosis. [3]
Indications for surgical fixation of tricuspidal issues include organic lesion(s) in the valve or severe functional regurgitation. During open heart surgery for another issue (e.g. mitral valve), fixing the tricuspid valve may be considered, but medical consensus is unclear. Some argue that even mild to moderate tricuspid regurgitation should be addressed, while others take a more conservative approach. Infective endocarditis or traumatic lesions are other indications. [14]
Surgical options include annuloplasty or replacement of the valve. Adding a rigid prosthetic ring aims to decrease the diameter of the valve and stabilize it. Another annuloplasty modality is the "De Vega technique", in which the valve diameter is decreased by two sutures placed around the periphery of the valve. In cases of severe organic lesions of the valve, such as endocarditis, the valve may be excised. Tricuspid valve replacement with either a mechanical valve or a bioprosthesis may be indicated depending on the patient. [15] Mechanical prostheses can cause thromboembolic phenomena, while bioprostheses may degenerate with use. [11] Some evidence suggests that there is no significant difference between the survival rates of recipients of mechanical versus biological tricuspid valves. [16] [15]
When controlled for severity of TR, tricuspid valve surgery performed on TR patients as considered appropriate is associated with improved outcomes (Hazard ratio= .74). [17]
The prognosis of TR is less favorable for females than males. Females are at a greater risk of progressing to severe TR as compared to males. [3] Survival rates are proportional to TR severity; [18] but even mild TR reduces survival compared to those with no TR. In some studies, the 1 year mortality rate of severe, medically treated TR is 36-42% with a 2-3.2 times increased risk of death in moderate or severe TR as compared to mild TR or no tricuspid valvular disease. [3] Even in those with mild TR, a large population based study showed about a 29% greater risk of death as compared to healthy controls. [19]
In The Framingham Heart Study, presence of tricuspid regurgitation of mild severity or greater, was present in about 14.8% of men and 18.4% of women. [20] Mild tricuspid regurgitation tends to be common and, in the presence of a structurally normal tricuspid valve apparatus, can be considered a normal variant. [21] Clinically significant TR is more common in females, this is thought to be partly driven by the increased prevalence of atrial fibrillation and heart failure with preserved ejection fraction (both risk factors for TR) in women as compared to men. [3] Moderate or severe tricuspid regurgitation is usually associated with tricuspid valve leaflet abnormalities and/or possibly annular dilation and is usually pathologic which can lead to irreversible damage of cardiac muscle and worse outcomes due to chronic prolonged right ventricular volume overload. [22]
In a study of 595 male elite football players aged 18–38, and 47 sedentary non-athletes, it was found that 58% of the athletes had tricuspid regurgitation vs. 36% in non-athletes. Football players with tricuspid regurgitation had larger tricuspid annulus diameter, compared to athletes without tricuspid regurgitation. Athletes with tricuspid regurgitation also had enlarged right atrium diameter when compared to control group. [23]
Aortic stenosis is the narrowing of the exit of the left ventricle of the heart, such that problems result. It may occur at the aortic valve as well as above and below this level. It typically gets worse over time. Symptoms often come on gradually with a decreased ability to exercise often occurring first. If heart failure, loss of consciousness, or heart related chest pain occur due to AS the outcomes are worse. Loss of consciousness typically occurs with standing or exercising. Signs of heart failure include shortness of breath especially when lying down, at night, or with exercise, and swelling of the legs. Thickening of the valve without causing obstruction is known as aortic sclerosis.
A heart valve is a biological one-way valve that allows blood to flow in one direction through the chambers of the heart. Four valves are usually present in a mammalian heart and together they determine the pathway of blood flow through the heart. A heart valve opens or closes according to differential blood pressure on each side.
The mitral valve, also known as the bicuspid valve or left atrioventricular valve, is one of the four heart valves. It has two cusps or flaps and lies between the left atrium and the left ventricle of the heart. The heart valves are all one-way valves allowing blood flow in just one direction. The mitral valve and the tricuspid valve are known as the atrioventricular valves because they lie between the atria and the ventricles.
The tricuspid valve, or right atrioventricular valve, is on the right dorsal side of the mammalian heart, at the superior portion of the right ventricle. The function of the valve is to allow blood to flow from the right atrium to the right ventricle during diastole, and to close to prevent backflow (regurgitation) from the right ventricle into the right atrium during right ventricular contraction (systole).
Heart murmurs are unique heart sounds produced when blood flows across a heart valve or blood vessel. This occurs when turbulent blood flow creates a sound loud enough to hear with a stethoscope. The sound differs from normal heart sounds by their characteristics. For example, heart murmurs may have a distinct pitch, duration and timing. The major way health care providers examine the heart on physical exam is heart auscultation; another clinical technique is palpation, which can detect by touch when such turbulence causes the vibrations called cardiac thrill. A murmur is a sign found during the cardiac exam. Murmurs are of various types and are important in the detection of cardiac and valvular pathologies.
Tetralogy of Fallot (TOF), formerly known as Steno-Fallot tetralogy, is a congenital heart defect characterized by four specific cardiac defects. Classically, the four defects are:
Mitral valve prolapse (MVP) is a valvular heart disease characterized by the displacement of an abnormally thickened mitral valve leaflet into the left atrium during systole. It is the primary form of myxomatous degeneration of the valve. There are various types of MVP, broadly classified as classic and nonclassic. In severe cases of classic MVP, complications include mitral regurgitation, infective endocarditis, congestive heart failure, and, in rare circumstances, cardiac arrest.
Mitral stenosis is a valvular heart disease characterized by the narrowing of the opening of the mitral valve of the heart. It is almost always caused by rheumatic valvular heart disease. Normally, the mitral valve is about 5 cm2 during diastole. Any decrease in area below 2 cm2 causes mitral stenosis. Early diagnosis of mitral stenosis in pregnancy is very important as the heart cannot tolerate increased cardiac output demand as in the case of exercise and pregnancy. Atrial fibrillation is a common complication of resulting left atrial enlargement, which can lead to systemic thromboembolic complications such as stroke.
Aortic regurgitation (AR), also known as aortic insufficiency (AI), is the leaking of the aortic valve of the heart that causes blood to flow in the reverse direction during ventricular diastole, from the aorta into the left ventricle. As a consequence, the cardiac muscle is forced to work harder than normal.
Mitral regurgitation (MR), also known as mitral insufficiency or mitral incompetence, is a form of valvular heart disease in which the mitral valve is insufficient and does not close properly when the heart pumps out blood. It is the abnormal leaking of blood backwards – regurgitation from the left ventricle, through the mitral valve, into the left atrium, when the left ventricle contracts. Mitral regurgitation is the most common form of valvular heart disease.
Ebstein's anomaly is a congenital heart defect in which the septal and posterior leaflets of the tricuspid valve are displaced downwards towards the apex of the right ventricle of the heart. EA has great anatomical heterogeneity that generates a wide spectrum of clinical features at presentation and is complicated by the fact that the lesion is often accompanied by other congenital cardiac lesions. It is classified as a critical congenital heart defect accounting for less than 1% of all congenital heart defects presenting in around 1 per 200,000 live births. Ebstein's anomaly usually presents with a systolic murmur and frequently with a gallop rhythm.
A transthoracic echocardiogram (TTE) is the most common type of echocardiogram, which is a still or moving image of the internal parts of the heart using ultrasound. In this case, the probe is placed on the chest or abdomen of the subject to get various views of the heart. It is used as a non-invasive assessment of the overall health of the heart, including a patient's heart valves and degree of heart muscle contraction. The images are displayed on a monitor for real-time viewing and then recorded.
Valvular heart disease is any cardiovascular disease process involving one or more of the four valves of the heart. These conditions occur largely as a consequence of aging, but may also be the result of congenital (inborn) abnormalities or specific disease or physiologic processes including rheumatic heart disease and pregnancy.
Aortic valve repair or aortic valve reconstruction is the reconstruction of both form and function of a dysfunctional aortic valve. Most frequently it is used for the treatment of aortic regurgitation. It can also become necessary for the treatment of aortic aneurysm, less frequently for congenital aortic stenosis.
Right ventricular hypertrophy (RVH) is a condition defined by an abnormal enlargement of the cardiac muscle surrounding the right ventricle. The right ventricle is one of the four chambers of the heart. It is located towards the right lower chamber of the heart and it receives Deoxygenated blood from the right upper chamber and pumps blood into the lungs.
Regurgitation is blood flow in the opposite direction from normal, as the backward flowing of blood into the heart or between heart chambers. It is the circulatory equivalent of backflow in engineered systems. It is sometimes called reflux.
Uhl anomaly is a rare cardiac malformation that was first identified by Dr. Henry Uhl in 1952. It is characterized by the absence of the right ventricle (RV) myocardium, either entirely or partially, and the replacement of the RV myocardium by nonfunctional fibroelastic tissue that resembles parchment. As of 2010 less than 100 cases have been reported in literature.
Mitral valve replacement is a procedure whereby the diseased mitral valve of a patient's heart is replaced by either a mechanical or tissue (bioprosthetic) valve.
The following outline is provided as an overview of and topical guide to cardiology, the branch of medicine dealing with disorders of the human heart. The field includes medical diagnosis and treatment of congenital heart defects, coronary artery disease, heart failure, valvular heart disease and electrophysiology. Physicians who specialize in cardiology are called cardiologists.
Transcatheter pulmonary valve replacement (TPVR), also known as percutaneous pulmonary valve implantation (PPVI), is the replacement of the pulmonary valve via catheterization through a vein. It is a significantly less invasive procedure in comparison to open heart surgery and is commonly used to treat conditions such as pulmonary atresia.