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Overview of the management of patients with prosthetic heart valves

Overview of the management of patients with prosthetic heart valves
Literature review current through: Jan 2024.
This topic last updated: Mar 04, 2022.

INTRODUCTION — Surgical replacement of a diseased heart valve with a prosthetic valve or transcatheter implantation of a prosthetic valve can provide substantial clinical benefits. However, such procedures exchange the adverse effects of native disease for prosthesis-related complications [1,2]. The frequency of various complications depends upon the valve type and position, and other clinical risk factors. Complications include embolic events, bleeding, valve obstruction (due to thrombosis or pannus), infective endocarditis, structural deterioration (particularly for bioprosthetic valves), paravalvular regurgitation, hemolytic anemia, and prosthesis-patient mismatch. (See "Mechanical prosthetic valve thrombosis or obstruction: Clinical manifestations and diagnosis".)

Management of patients with prosthetic valves, including monitoring for complications, is reviewed here. Issues related to antithrombotic therapy in patients (including pregnant women) with prosthetic valves, management of complications, choice of prosthetic valve, transcatheter aortic valve replacement, and prosthesis-patient mismatch are discussed separately. (See "Antithrombotic therapy for mechanical heart valves" and "Anticoagulation for prosthetic heart valves: Management of bleeding and invasive procedures" and "Mechanical prosthetic valve thrombosis or obstruction: Clinical manifestations and diagnosis" and "Management of antithrombotic therapy for a prosthetic heart valve during pregnancy" and "Choice of intervention for severe calcific aortic stenosis" and "Surgical procedures for severe chronic mitral regurgitation" and "Choice of prosthetic heart valve for surgical aortic or mitral valve replacement", section on 'Prosthetic valve-patient mismatch'.)

SERIAL FOLLOW-UP

Goals — The goals of serial follow-up of patients with prosthetic valves include identification of changes in clinical status, management of antithrombotic therapy, monitoring for complications, identification of changes in valve function, and provision of patient education.

Patient education — Patients should be educated about prosthetic valve outcomes, the need for proper care (including optimal dental care, the need for antibiotic prophylaxis for dental procedures, and when required, appropriate antithrombotic therapy) and should be instructed to seek prompt medical attention for any new sign or symptom that might be related to a valve complication such as a significant change in the audible click of a mechanical prosthesis, persistent or recurrent fever, decrease in exercise tolerance, ischemic cerebral events, or palpitations. Repeat evaluation with echocardiography should be performed any time there is a change in clinical status or examination findings. (See 'Infective endocarditis' below.)

Schedule of follow-up — The main components of follow-up are history, physical examination, and echocardiography. We suggest the following approach to evaluation after prosthetic valve implantation, largely based on the 2020 American College of Cardiology/American Heart Association guideline on the management of patients with valvular heart disease [1]:

The first outpatient visit at six weeks (or earlier if an issue was identified at discharge such as heart failure or pericardial effusion or if new symptoms or signs arise) to three months after valve implantation is aimed at assessing function of the prosthetic valve and looking for signs of infection, conduction disturbance, or myocardial infarction. The evaluation should include an interval history, physical examination, appropriate blood tests (complete blood count, creatinine, electrolytes, lactate dehydrogenase, and International Normalized Ratio if indicated), and a transthoracic echocardiogram. An electrocardiogram (ECG) may be obtained, if indicated.

A baseline echocardiogram is essential since it enables assessment of the effects of surgery on cardiac remodeling and function, and serves as a basis for later comparison, particularly for valvular hemodynamics obtained with Doppler.

Follow-up clinical evaluation with transthoracic echocardiography (TTE; and transesophageal echocardiography [TEE] as needed) should be performed any time there is a change in clinical symptoms or signs suggestive of valve dysfunction, or, in patients with mechanical valves, an interruption in effective anticoagulation.

Routine follow-up visits in asymptomatic patients with normal cardiac function should occur yearly. The evaluation should include a complete history and physical examination; other tests are performed as indicated.

In asymptomatic patients with mechanical valves without evidence of left ventricular or valve dysfunction, routine annual echocardiography to monitor the valve is not indicated.

For patients with a surgically implanted bioprosthetic valve, a TTE at 5 and 10 years, and then annually after implantation, is reasonable, even in the absence of symptoms or of a change in clinical status. Earlier surveillance is suggested for selected patients at risk for early bioprosthetic valve degeneration, including patients with hyperparathyroidism (including patients with kidney disease), systemic inflammatory disease, and patients <60 years old.

For transcatheter aortic and pulmonic bioprosthetic valves, we recommend annual echocardiography, as the long-term durability of these valves has not yet been established. In addition, many patients are enrolled in mandated valve registries that require annual imaging. (See "Choice of intervention for severe calcific aortic stenosis" and "Transcatheter pulmonary valve implantation".)

In addition to routine monitoring of prosthetic heart valves, periodic echocardiography is frequently indicated in patients with prosthetic valves for residual cardiac abnormalities, such as left ventricular dilation or systolic dysfunction, diastolic dysfunction, abnormalities of native valves, and persistent pulmonary hypertension.

History and physical examination — When performing a history and physical examination in patients with prosthetic heart valve, particular attention should be given to the following signs and symptoms:

Subtle symptoms of heart failure or neurologic events can be clues to serious valve-related complications. In a patient with a prosthetic heart valve, new symptoms or signs should be carefully considered to determine if they may be caused by a valve complication. The physical findings may identify signs of embolic events suggested by the history.

Abnormal auscultatory findings may be suggestive of valvular abnormalities (table 1) [3]. With a mechanical valve, absence or blunting of typical opening and closing sounds may be suggestive of valve thrombosis. With both mechanical and biological valves, a new murmur suggests prosthetic valve stenosis, regurgitation, or a paravalvular leak. Interpretation of auscultatory findings in patients with prosthetic heart valves is difficult even for experienced clinicians. (See "Auscultation of cardiac murmurs in adults".)

Echocardiography — As noted above, a baseline echocardiogram is recommended in all patients at their first postoperative follow-up visit. This study is used to document the stability of the valve, the presence and extent of valvular or paravalvular regurgitation, and the transvalvular pressure gradients. Methods to evaluate surgical and percutaneous prosthetic valve function with Doppler echocardiography are detailed in the guidelines from the American Society of Echocardiography [4,5]. The postoperative baseline echocardiogram also establishes whether there are concurrent conditions (left ventricular dysfunction, pericardial effusion, pulmonary hypertension, or other valve involvement) that might warrant more frequent imaging than needed for monitoring the prosthetic valve. (See "Echocardiographic evaluation of prosthetic heart valves".)

TTE is generally used for the baseline study; TEE may be indicated in select patients to assess valve dysfunction (eg, those with a suspected paravalvular leak from a mitral prosthesis), or patients with a suspected cardiac source of embolism (movie 1A-C) [6,7].

Doppler-derived velocities and derived parameters are essential in the noninvasive evaluation of prosthetic valve function [4]. One study, for example, found that application of the continuity equation and calculation of valve resistance provided a reliable method to distinguish whether a high velocity and gradient across a St. Jude aortic valve was secondary to obstruction or increased flow (as with paravalvular aortic regurgitation) [8]. Parameters that differentiated stenotic from regurgitant and normal valves were effective orifice area, Doppler velocity index, and valve resistance. (See "Aortic valve area in aortic stenosis in adults".)

Other diagnostic studies — Other studies are rarely indicated in patients with no symptoms related to the prosthetic heart valve and no abnormal physical exam findings. Imaging in patients with complications is discussed separately. (See "Mechanical prosthetic valve thrombosis or obstruction: Clinical manifestations and diagnosis".)

ECG and chest radiograph are not performed on a routine basis in the absence of a specific indication.

COMPLICATIONS

Overview — The incidence of serious complications in appropriately managed patients with prosthetic heart valves is approximately 3 percent per year. The frequency of various complications depends upon the valve type (mechanical versus bioprosthetic), position, and multiple clinical risk factors, including adequacy of anticoagulation. Patients with prosthetic valves are at risk for the following complications:

Thromboembolism.

Valve obstruction (which may be caused by valve thrombosis, pannus formation, bioprosthetic valve fibrosis, prosthesis-patient mismatch, and/or calcification). (See "Choice of prosthetic heart valve for surgical aortic or mitral valve replacement", section on 'Prosthetic valve-patient mismatch' and "Bioprosthetic valve thrombosis, thromboembolism, and obstruction: Management".)

Valve regurgitation and paravalvular regurgitation.

Bleeding related to antithrombotic therapy. (See "Anticoagulation for prosthetic heart valves: Management of bleeding and invasive procedures", section on 'Management of bleeding'.)

Infective endocarditis. (See 'Endocarditis prophylaxis' below and "Antimicrobial therapy of prosthetic valve endocarditis" and "Surgery for prosthetic valve endocarditis".)

Hemolytic anemia. (See 'Hemolytic anemia' below.)

Two of the above complications (infective endocarditis and hemolytic anemia) are discussed here; the other complications are discussed separately.

Complications following transcatheter aortic valve replacement and percutaneous pulmonic valve implantation are discussed separately. (See "Transcatheter aortic valve implantation: Complications" and "Transcatheter pulmonary valve implantation", section on 'Complications by valve type'.)

Infective endocarditis — Issues related to the presentation, diagnosis, antithrombotic management, and antimicrobial and surgical therapy of prosthetic valve endocarditis are discussed separately. (See "Prosthetic valve endocarditis: Epidemiology, clinical manifestations, and diagnosis" and "Antithrombotic therapy in patients with infective endocarditis" and "Antimicrobial therapy of prosthetic valve endocarditis" and "Surgery for prosthetic valve endocarditis".)

Endocarditis prophylaxis is discussed below. (See 'Endocarditis prophylaxis' below.)

Hemolytic anemia

Incidence — In patients with newer generation prosthetic valves (those used since approximately the 1990s), hemolysis is common (eg, in one series, 51.2 percent in patients with St. Jude valves and 17.8 percent in patients with Medtronic Hall valves [9]) but usually mild and subclinical, reflected by mild elevations in the serum lactate dehydrogenase concentration. Hemolytic anemia is seen more commonly with mechanical heart valves than with bioprosthetic valves. Hemolysis severe enough to produce anemia is rare (<1 percent) with newer generation prosthetic valves [10]; in patients with these valves, hemolysis is associated with paravalvular regurgitation [9,11,12] or, less commonly, bioprosthetic structural degeneration [13].

Severe hemolysis was previously reported in up to 15 percent of patients with certain older valve prostheses, such as ball valves and certain older bileaflet valves, which may have been at least partly related to structural deterioration [10] not seen in current generation valves.

Clinical manifestations — Presenting features may be subtle and include anemia, heart failure, jaundice, dark urine, increasing serum lactate dehydrogenase, and a new or changed regurgitant murmur [14]. The peripheral smear shows variable numbers of schistocytes and smaller red cell fragments consistent with a microangiopathic process (picture 1). (See "Non-immune (Coombs-negative) hemolytic anemias in adults", section on 'Intravascular devices'.)

Diagnosis and evaluation — The diagnosis is made in a patient with a prosthetic valve presenting with intravascular hemolytic anemia. (See "Diagnosis of hemolytic anemia in adults".)

A transthoracic echocardiogram is performed to assess prosthetic valve gradients and regurgitation, including paravalvular regurgitation. A transesophageal echocardiogram should also be performed, particularly in patients with mitral prosthetic heart valves.

Management — Oral iron and folate replacement are effective in the majority of patients. In occasional patients, red cell transfusion is required; in such cases, the administration of recombinant human erythropoietin may eliminate the need for transfusion [15]. Reoperation may be required, especially if hemolysis is due to regurgitation from a paravalvular leak or valve failure. It is important to note that the degree of regurgitation does not have to be severe to cause hemolysis, as it is mainly secondary to shear forces from the high velocity jet hitting adjacent structures. (See "Clinical manifestations and diagnosis of surgical aortic and mitral prosthetic valve regurgitation", section on 'Blood tests'.)

ANTITHROMBOTIC THERAPY — Antithrombotic therapy with vitamin K antagonist (eg, warfarin) and/or aspirin is recommended in patients with prosthetic heart valves to prevent valve thrombosis and thromboembolic events. Recommendations for therapy vary with the type of valve (the risk is much greater with mechanical valves), the site of valve replacement (the risk is greater with mitral than aortic valves), and the presence or absence of underlying risk factors for thrombus formation. The benefits of anticoagulation therapy must be weighed against the risks of anticoagulant therapy, including bleeding. These issues are discussed in detail separately. (See "Antithrombotic therapy for mechanical heart valves".)

Specific recommendations apply to management of antithrombotic therapy during pregnancy and during invasive procedures. (See "Management of antithrombotic therapy for a prosthetic heart valve during pregnancy" and "Anticoagulation for prosthetic heart valves: Management of bleeding and invasive procedures", section on 'Planning for invasive procedures'.)

ENDOCARDITIS PROPHYLAXIS — Patients with prosthetic valves are among those at highest risk of an adverse outcome from infective endocarditis. Patient education should include instruction regarding the risk of infective endocarditis, the importance of optimal dental hygiene and regular dental care, the need for endocarditis prophylaxis at the time of relevant procedures, and the importance of seeking medical attention, including blood cultures promptly if symptoms of endocarditis develop. Antimicrobial prophylaxis is recommended in the setting of relevant procedures likely to result in bacteremia with a microorganism that has the potential ability to cause endocarditis (eg, dental procedures that involve manipulation of gingival tissue or the periapical region of the teeth, or perforation of the oral mucosa, such as tooth extraction and routine dental cleaning). Relevant procedures and recommended regimens are discussed in detail separately. (See "Prevention of endocarditis: Antibiotic prophylaxis and other measures" and "Prosthetic valve endocarditis: Epidemiology, clinical manifestations, and diagnosis".)

The importance of antibiotic prophylaxis was illustrated in a study of 533 patients with prosthetic heart valves [16]. Antibiotics were administered to 304 patients prior to undergoing invasive procedures thought to be capable of causing bacteremia with organisms known or likely to cause endocarditis, while 229 similar patients did not receive antimicrobial therapy. Endocarditis developed in 6 of the 229 (2.7 percent) untreated patients versus none of the 304 treated patients. (See "Prosthetic valve endocarditis: Epidemiology, clinical manifestations, and diagnosis".)

EXERCISE RECOMMENDATIONS — Regular moderate exercise to maintain cardiovascular fitness is encouraged. Limited data are available to guide exercise recommendations for patients following valve replacement or repair. We agree with the following recommendations included in the 2015 American Heart Association/American College of Cardiology Scientific Statement of Eligibility and Disqualification Recommendations for Competitive Athletes with Cardiovascular Abnormalities [17]:

It is reasonable for athletes with aortic or mitral bioprosthetic valves, not taking anticoagulant agents, who have normal valvular function and normal left ventricular function to participate in low-intensity and some moderate-intensity competitive sports (classes IA, IB, IC, and IIA) (figure 1).

Athletes with aortic or mitral mechanical valves taking anticoagulant agents with normal valvular function and normal left ventricular function can reasonably participate in low-intensity competitive sports if there is low likelihood of bodily contact (classes IA, IB, and IIA) (figure 1 and table 2).

Athletes who have undergone mitral valve repair for MR or surgical aortic valve repair have no or mild residual aortic or mitral regurgitation, and have normal left ventricular systolic function may be considered for participation in sports at the discretion of the managing physician if there is low likelihood of bodily contact (classes IA, IB, and IIA) (figure 1 and table 2)

The scientific statement suggests exercise stress testing (in some cases with assessment of prosthetic valve function during exercise) to at least the level of activity performed in the competitive sport as a means of assessing the athlete’s exercise capacity.

The increased cardiac output that occurs during exercise produces increased transvalvular pressure gradients that are of uncertain clinical significance. Limited data are available on the effects of vigorous exercise on prosthetic valve function [18].

PREGNANCY — Pregnancy presents a unique set of issues for women with prosthetic valves. Pregnancy in women with mechanical heart valves is complicated by the need for anticoagulant therapy to prevent valve thrombosis and thromboembolism. While warfarin is the most effective therapy to prevent valve thrombosis and thromboembolism, warfarin use is associated with an increased risk of fetal anomalies and a high risk of late fetal loss. These and other issues related to prosthetic valves during pregnancy and the peripartum period are discussed in detail separately. (See "Management of risks of prosthetic valves during pregnancy" and "Management of antithrombotic therapy for a prosthetic heart valve during pregnancy".)

SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Cardiac valve disease".)

INFORMATION FOR PATIENTS — UpToDate offers two types of patient education materials, “The Basics” and “Beyond the Basics.” The Basics patient education pieces are written in plain language, at the 5th to 6th grade reading level, and they answer the four or five key questions a patient might have about a given condition. These articles are best for patients who want a general overview and who prefer short, easy-to-read materials. Beyond the Basics patient education pieces are longer, more sophisticated, and more detailed. These articles are written at the 10th to 12th grade reading level and are best for patients who want in-depth information and are comfortable with some medical jargon.

Here are the patient education articles that are relevant to this topic. We encourage you to print or e-mail these topics to your patients. (You can also locate patient education articles on a variety of subjects by searching on “patient info” and the keyword(s) of interest.)

Basics topic (see "Patient education: Prosthetic valves (The Basics)")

SUMMARY AND RECOMMENDATIONS

The goals of serial follow-up of patients with prosthetic valves include identification of changes in clinical status, management of antithrombotic therapy, monitoring for complications, identification of changes in valve function, and provision of patient education. (See 'Goals' above.)

Patients should receive education reinforcing the importance of seeking prompt medical attention for any new sign or symptom that might be related to a valve complication such as fever, change in mechanical valve clicks, change in exercise tolerance, stroke symptoms, palpitations, or chest pain.

Serious complications of prosthetic heart valves occur at the rate of approximately 3 percent per year. The complications include thromboembolism, bleeding (particularly in patients receiving anticoagulation), prosthetic heart valve obstruction (caused by valve thrombosis, pannus formation, bioprosthetic valve fibrosis, prosthesis-patient mismatch, and/or calcification), valvular and paravalvular regurgitation, infective endocarditis, and prosthesis related hemolysis. (See 'Complications' above.)

Antithrombotic therapy with warfarin (or other vitamin K antagonist) and/or aspirin is recommended in patients with prosthetic heart valves to prevent valve thrombosis and thromboembolic events. Recommendations for therapy vary with the type of valve (the risk of thrombosis is much greater with mechanical valves), the site of valve replacement (the risk is greater with mitral than aortic valves), and the presence or absence of thrombotic risk factors, including atrial fibrillation. Specific recommendations apply to management of antithrombotic therapy during pregnancy and during invasive procedures. (See 'Antithrombotic therapy' above and "Antithrombotic therapy for mechanical heart valves".)

For all patients receiving a prosthetic heart valve, a baseline echocardiogram is recommended at first postoperative follow-up visit six weeks to three months after prosthetic valve implantation. (See 'Serial follow-up' above.)

In asymptomatic patients with mechanical valves without evidence of left ventricular or valve dysfunction, routine annual echocardiography is not indicated. Surgical bioprosthetic valves should be imaged annually starting 10 years after implantation with earlier evaluation in those at risk of more rapid valve deterioration. Transcatheter bioprosthetic valves should be imaged annually. (See 'Echocardiography' above.)

Repeat evaluation with echocardiography should be performed any time there is a change in clinical status or examination findings. (See 'Serial follow-up' above.)

Patients with prosthetic valves are among those at highest risk of an adverse outcome from infective endocarditis and thus optimal dental care is essential, and antimicrobial prophylaxis is recommended in the setting of procedures likely to result in bacteremia with a microorganism that has the potential ability to cause endocarditis. (See "Prevention of endocarditis: Antibiotic prophylaxis and other measures".)

Hemolysis associated with prosthetic heart valves is more common with mechanical than bioprosthetic valves. It is usually mild and subclinical but is severe in certain patients with paravalvular regurgitation. (See 'Hemolytic anemia' above.)

Regular moderate exercise to maintain cardiovascular fitness is encouraged in patients with prosthetic valves. Recommendations for competitive sports vary depending upon valve type and need for anticoagulation. All patients treated with anticoagulation should not participate in sports associated with risk of bodily contact or other types of trauma (table 2). (See 'Exercise recommendations' above.)

Pregnancy in women with prosthetic mechanical heart valves is complicated by the need for antithrombotic therapy. While warfarin is the most effective therapy to prevent valve thrombosis and thromboembolism, warfarin use is associated with an increased risk of fetal anomalies and a high risk of late fetal loss. These and other issues related to prosthetic valves during pregnancy and the peripartum period are discussed in detail separately. (See "Management of risks of prosthetic valves during pregnancy" and "Management of antithrombotic therapy for a prosthetic heart valve during pregnancy".)

ACKNOWLEDGMENTS — The UpToDate editorial staff acknowledges Gerard P Aurigemma, MD, who contributed to earlier versions of this topic review.

The UpToDate editorial staff acknowledges William Gaasch, MD (deceased), who contributed to an earlier version of this topic review.

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