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Principles of medical therapy for patients with valvular heart disease


Key points

  • Patients with valvular heart disease (VHD) are best cared for in the context of a multidisciplinary heart valve clinic.

  • Many adverse outcomes for adults with VHD are caused by sequelae of the disease process, including atrial fibrillation (AF), embolic events, left ventricular (LV) dysfunction, pulmonary hypertension, and endocarditis.

  • Medical treatment of adults with VHD focuses on prevention and treatment of complications because there are no specific therapies to prevent progression of valve disease.

  • Infective endocarditis (IE) prophylaxis guidelines recommend antibiotics before dental or other procedures associated with bacteremia for adults with prosthetic valves but not for patients with native valve disease.

  • Periodic evaluation of disease severity and the LV response to chronic volume and pressure overload allows optimal timing of surgical and percutaneous interventions.

  • General health maintenance is important, including evaluation and treatment of coronary disease risk factors, regular exercise, standard immunizations, and optimal dental care.

  • Management of concurrent cardiovascular disease follows standard approaches with modification as needed, based on the potential confounding effects of valve hemodynamics.

  • Standard guidelines for anticoagulation are appropriate in patients with AF and native aortic valve disease, tricuspid valve disease, or mitral regurgitation. In patients with AF and a bioprosthetic valve or mitral valve repair, anticoagulation is recommended regardless of risk score. Either a direct oral anticoagulant or a vitamin K antagonist is appropriate in these patients.

  • In AF patients with rheumatic mitral stenosis or a mechanical heart valve, vitamin K antagonists should be used for anticoagulation.

  • For patients with valvular disease undergoing noncardiac surgery, management focuses on an accurate assessment of disease severity and symptom status, with appropriate hemodynamic monitoring and optimization of loading conditions in the perioperative period.

  • Evaluation of coronary anatomy usually is needed before valve surgery because of the high prevalence of coronary disease and improved surgical outcomes with concurrent coronary revascularization.

The heart valve clinic

For patients with valvular heart disease (VHD), the basic principles of management include the following:

  • Obtain an accurate diagnosis of the specific valvular lesion and quantitative disease severity using the history, physical examination, Doppler echocardiography, and other advanced imaging modalities.

  • Monitor asymptomatic patients who have moderate or severe valve disease.

  • Prevent and manage complications of the disease process, such as endocarditis, atrial fibrillation (AF), and embolic events.

  • Periodically re-evaluate ventricular size and function to identify early ventricular dysfunction and optimize the timing of surgical or percutaneous intervention.

  • Provide optimal management of associated conditions.

  • Set and maintain standards for valve interventions, including surgical valve repair and replacement and percutaneous techniques.

  • Provide patient education regarding the disease process, expected outcomes, symptom surveillance, and potential medical or surgical therapies.

  • Assess before noncardiac surgery or pregnancy.

These goals are best met with an interdisciplinary health care team structured as a heart valve clinic. Many general cardiologists have little experience in managing these complex patients despite the fact that moderate or severe heart valve disease occurs in 13% of persons 75 years of age or older as a result of degenerative diseases reflecting increasing life spans. Data from the Euro Heart Surveys shows that many patients are not treated according to current guidelines. Some are inappropriately denied interventions that would improve survival and quality of life, whereas others undergo intervention earlier in the disease course than necessary.

Optimal decision making requires input from cardiologists with expertise in valve disease, interventional cardiologists, imaging specialists, and cardiovascular surgeons. Other experts, such as neurologists, anesthesiologists, and palliative care specialists, may also need to be involved with the heart team in certain circumstances ( Fig. 6.1 ). There is also an emerging role in the management of patients with cardiac implanted device infections for individuals with expertise in removal of pacemaker or defibrillator leads and generators. With the use of telemedicine, it may be reasonable to manage patients with lower-acuity VHD in a center without on-site multispecialty care through telecommunication with a heart valve team. The European Society of Cardiology published a position paper on the need for heart valve clinics, with specific recommendations for goals, patient population, clinic structure, and the tasks for each member of the heart valve clinic team.

Fig. 6.1, Functioning of the Advanced Heart Valve Clinic.

Diagnosis of valve disease

VHD may first be diagnosed in the setting of an acute medical event, such as heart failure, pulmonary edema, AF, or infective endocarditis (IE). More often, the diagnosis of VHD is suspected before the onset of overt symptoms, based on the physical examination finding of a cardiac murmur, screening of relatives in a family with a history of a genetic disorder, or abnormal findings on an electrocardiograph, chest radiograph, or echocardiogram requested for unrelated reasons ( Box 6.1 ). Worldwide, many patients are first diagnosed with VHD when a cardiac murmur is heard during an episode of acute rheumatic fever.

BOX 6.1
Modified from Nishimura RA, Otto CM, Bonow RO, et al. 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. J Am Coll Cardiol 2014;63:e57-e185.
Echocardiographic Indications for Adults With Suspected or Known Valvular Heart Disease

Suspected valvular disease

  • Cardiac murmur in a patient with cardiorespiratory symptoms

  • Murmur suggesting structural heart disease, even if asymptomatic

    • Diastolic murmur

    • Continuous murmur

    • Holosystolic or late systolic murmur

    • Murmur associated with an ejection click or irradiation of neck or back

    • Grade 3 or louder mid-peaking systolic murmur

Known native valve disease

  • Stenosis

    • Initial diagnosis and assessment of hemodynamic severity

    • Assessment of left and right ventricular size, function, and hemodynamics

    • Re-evaluation for changing signs or symptoms

    • Assessment of changes in valve or ventricular function during pregnancy

    • Periodic re-evaluation

    • Assessment of pulmonary pressures with exercise in mitral stenosis patients when there is a discrepancy between symptoms and resting hemodynamics

    • TEE before percutaneous valvotomy in patients with mitral stenosis

  • Regurgitation

    • Initial diagnosis and assessment of hemodynamic severity

    • Initial evaluation of left and right ventricular size, function, and hemodynamics

    • Assessment of aortic regurgitation in cases of aortic root enlargement

    • Re-evaluation with a change in symptoms

    • Periodic re-evaluation even in asymptomatic patients

    • Re-assessment of valve and ventricular function during pregnancy

  • Mitral valve prolapse

    • Assessment of leaflet morphology, hemodynamic severity, and ventricular compensation

  • Infective endocarditis a

    a TEE is usually required.

    • Detection of valvular vegetations with or without positive blood cultures

    • Characterization of hemodynamic severity with known endocarditis

    • Detection of complications such as abscesses, fistulas, and shunts

    • Re-evaluation of high-risk patients (e.g., virulent organism, clinical deterioration, persistent or recurrent fever, new murmur, persistent bacteremia)

Interventions for valvular disease

  • Selection of alternate therapies for mitral valve disease (e.g., balloon valvuloplasty, surgical valve repair vs. replacement, percutaneous approaches) a

  • Monitoring interventional techniques in the catheterization laboratory (i.e., 3D TEE, ICE, or TTE)

  • Intraoperative TEE for valve repair surgery

  • Intraoperative TEE for stentless bioprosthetic, homograft, autograft, or transaortic, transapical, or veno-aortic valve replacement interventions

  • Intraoperative TEE for valve surgery of infective endocarditis

Prosthetic valves

  • Baseline postoperative study (i.e., hospital discharge or 6–8 weeks)

  • Annual evaluation of bioprosthetic valves beginning 5 years after implantation

  • Changing clinical signs and symptoms or suspected prosthetic valve dysfunction a

  • Prosthetic valve endocarditis

    • Detection of endocarditis and characterization of valve and ventricular function

    • Detection of endocarditis complications and re-evaluation in complex endocarditis a

    • Persistent fever without bacteremia or a new murmur a

    • Bacteremia without a known source a

ICE , Intracardiac echocardiography; TEE , transesophageal echocardiography; TTE , transthoracic echocardiography; 3D , three-dimensional.

In patients with a cardiac murmur, the first step is clinical assessment based on the history and physical examination. If clinical evaluation indicates a high likelihood of significant valvular disease, the next step is echocardiography to confirm the diagnosis and evaluate valve anatomy and function.

For a patient with cardiac or respiratory symptoms and a cardiac murmur on auscultation, it is prudent to obtain an echocardiogram to evaluate for possible valvular disease. When symptoms exist, it is difficult to reliably exclude significant valvular disease by physical examination because the findings may be subtle. For example, some patients with severe aortic stenosis have only a grade 2 or 3 murmur on examination, and the carotid upstroke may appear normal due to coexisting atherosclerosis. With the growing prevalence of obesity and decline in physical examination skills in many societies, the examination has also lost some sensitivity. , Diagnosis can be even more difficult in other situations. For example, many patients with acute mitral regurgitation have no audible murmur.

Among asymptomatic patients with a murmur detected on physical examination, those with a benign flow murmur should be distinguished from those with a pathologic murmur. Although there are no absolutely reliable criteria for making this distinction, a reasonable estimate of the pretest likelihood of disease can be derived from the history and physical examination findings. Flow murmurs, defined as audible systolic murmurs in the absence of structural heart disease, are most common in younger patients and in those with high output states. A flow murmur is a normal finding in pregnancy and is appreciated in 90% of pregnant women. Flow murmurs also are likely in patients who are anemic or febrile.

Typically, a flow murmur is systolic, is of low intensity (grade 1 to 2), is loudest at the base with little radiation, ends before the second heart sound, and has a crescendo-decrescendo or ejection shape with an early systolic peak. These murmurs are related to rapid ejection into the aorta or pulmonary artery in patients with normal valve function, high flow rates, and good transmission of sound to the chest wall. The yield of echocardiography is very low for asymptomatic patients with a typical flow murmur on examination, no cardiac history, and no cardiac symptoms on careful questioning.

Echocardiographic examination usually is appropriate in asymptomatic patients who have a diastolic or continuous murmur, a systolic murmur of grade 3 or higher, an ejection click or mid-systolic click, a holosystolic (rather than ejection) murmur, or an atypical pattern of radiation, even if the patient is asymptomatic. To some extent, the loudness of the murmur correlates with disease severity, but this is not reliable for decision making about an individual patient. , Echocardiography allows differentiation of valve disease from a flow murmur, identification of the specific valve involved, definition of the cause of valve disease, and quantitation of the hemodynamic severity of the lesion along with left ventricular (LV) size and function. Based on these data, the expected prognosis, need for preventive measures, and timing of subsequent examinations (if any) can be determined.

Distinguishing a benign from a pathologic murmur is more difficult in older rather than younger patients; many older patients have some degree of aortic valve sclerosis or mild mitral regurgitation that can be appreciated on auscultation, and many have mild symptoms that may or may not be related to heart disease. , In this setting, a baseline echocardiogram may be prudent. The finding of aortic sclerosis is associated with an increased risk of adverse cardiovascular events, and some patients have progressive valve obstruction. A soft mitral regurgitant murmur is most likely associated with mild to moderate regurgitation due to mitral annular calcification, but establishing the diagnosis with a baseline echocardiogram and excluding other causes of mitral regurgitation, such as ischemic disease or mitral valve prolapse, is appropriate.

Although echocardiography is the primary diagnostic modality used for evaluation of valve disease, cardiac magnetic resonance (CMR) imaging and computed tomography (CT) are useful in some cases (see Chapters 8 and 15 ). Diagnostic cardiac catheterization continues to be useful in selected patients, particularly when echocardiographic data are nondiagnostic or discrepant with other clinical data.

Preventive measures

Diagnosis and prevention of rheumatic fever

Rheumatic fever is a multiorgan inflammatory disease that occurs 10 days to 3 weeks after group A streptococcal pharyngitis. The clinical diagnosis is based on the conjunction of an antecedent streptococcal throat infection and classic manifestations of the disease, including carditis, polyarthritis, chorea, erythema marginatum, and subcutaneous nodules. Clinical guidelines for the diagnosis of rheumatic fever provide increased specificity because many of the manifestations of rheumatic fever are also seen in other conditions ( Box 6.2 ). Although these guidelines are helpful in the initial diagnosis of rheumatic fever, exceptions do occur, and consideration of the diagnosis is important in the recognition of this disease. Poststreptococcal reactive arthritis has some overlap in symptoms and signs with acute rheumatic fever but is not associated with cardiac involvement.

BOX 6.2
Modified from Ferrieri P, Jones Criteria Working Group. Proceedings of the Jones Criteria workshop. Circulation 2002;106:2521-2523.
Updated Jones Criteria for the Diagnosis of Initial Rheumatic Fever Attacks

Major criteria

  • Carditis (may involve endocardium, myocardium, and pericardium)

  • Polyarthritis (most frequent manifestation, usually migratory)

  • Chorea (documentation of recent group A streptococcal infection may be difficult)

  • Erythema marginatum (distinctive, evanescent rash on trunk and proximal extremities)

  • Subcutaneous nodules (firm, painless nodule on extensor surfaces of elbows, knees, and wrists)

Minor criteria

  • Clinical findings (arthralgia, fever)

  • Laboratory findings (elevated erythrocyte sedimentation rate or C-reactive protein level)

  • Electrocardiography (prolonged PR interval)

Evidence of antecedent group A streptococcal infection

  • Positive throat culture or rapid streptococci antigen test

  • Elevated or rising streptococcal antibody titer

High probability of rheumatic fever

  • 2 major criteria or 1 major criterion plus 2 minor criteria

PLUS

  • evidence of preceding group A streptococcal infection

The carditis associated with rheumatic fever is a pancarditis; the pericardium, myocardium, and valvular tissue may be involved. Rheumatic disease preferentially affects the mitral valve; mitral regurgitation is characteristic of the acute episode, whereas mitral stenosis is characteristic of the long-term effect of the disease process. Although echocardiography can increase the sensitivity of an early diagnosis of rheumatic fever, a slight degree of mitral regurgitation is common in normal individuals, and this is therefore not a specific finding.

Primary prevention of rheumatic fever is based on treatment of streptococcal pharyngitis with appropriate antibiotics for a sufficient length of time ( Table 6.1 ). Patients with a history of rheumatic fever are at high risk for recurrent disease leading to repeated episodes of valvulitis and increased damage to the valvular apparatus. Because recurrent streptococcal infections may be asymptomatic, secondary prevention is based on the use of continuous antibiotic therapy ( Table 6.2 ). The risk of recurrent disease is related to the number of previous episodes, time interval since the last episode, risk of exposure to streptococcal infections (i.e., contact with children or crowded situations), and patient age. A longer duration of secondary prevention is recommended for patients with evidence of carditis or persistent valvular disease than for those with no evidence of valvular damage.

TABLE 6.1
Recommendations for Prevention of Rheumatic Fever.
Modified from Shulman ST, Bisno AL, Clegg HW, et al. Clinical practice guideline for the diagnosis and management of group A streptococcal pharyngitis: 2012 update by the Infectious Diseases Society of America. Clin Infect Dis 2012;55:1279-1282.
Medication Adults Children (≤27 kg)
For Primary Prevention (i.e., Treatment of Group A Streptococcal Tonsillopharyngitis)
Oral penicillin V a (phenoxymethyl penicillin) 500 mg two to three times daily for 10 days 250 mg two to three times daily for 10 days
IM penicillin, single dose Penicillin G benzathine and penicillin G procaine (Bicillin C-R) 2.4 million units or penicillin G benzathine (Bicillin L-A) 1.2 million units Penicillin G benzathine and penicillin G procaine (Bicillin C-R 900/300) 1.2 million units (consists of benzathine penicillin G 900,000 units mixed with procaine penicillin G 300,000 units) b
Amoxicillin c , d 875 mg orally twice daily or 500 mg three times daily for 10 days 50 mg/kg/day orally (maximum 1000 mg/day); may be administered once daily or in two or three equally divided doses; duration is 10 days
Cephalexin d , e 500 mg orally twice daily for 10 days 25–50 mg/kg/day orally in two equally divided doses (maximum 1000 mg/day) for 10 days
For Potentially Severe Hypersensitivity to β-Lactam Antibiotics (e.g., Penicillin, Cephalosporins)
Azithromycin f 500 mg orally on day 1 followed by 250 mg daily on days 2 through 5 12 mg/kg orally once daily for 5 days
Clarithromycin 250 mg orally twice daily for 10 days 7.5 mg/kg/dose twice daily for 10 days
Clindamycin 28–70 kg: 20 mg/kg/day orally in three equally divided doses for 10 days
>70 kg: 450–600 mg/day orally three times daily for 10 days		 20 mg/kg/day orally in three equally divided doses for 10 days
Cefadroxil — 30 mg/kg once daily (maximum 1000 mg/day) for 10 days

a Oral penicillin V is the drug of choice for group A streptococcal pharyngitis.

b Penicillin G benzathine and penicillin G procaine (Bicillin C-R 900/300) requires further study before routine use in adults or large adolescents is acceptable. Bicillin L-A (benzathine penicillin G 600,000 units IM) is an acceptable alternative regimen for patients < 27 kg.

c Although single-dose amoxicillin is recommended by the 2009 American Health Association guidelines, its superiority over the doses listed has not been proved definitively, and it is not approved for children younger than 12 years of age.

d Dose alteration needed for severe renal insufficiency.

e Other cephalosporins (i.e., cefadroxil, cefprozil, cefaclor, cefuroxime, loracarbef, cefdinir, cefpodoxime, cefixime, and ceftibuten) are acceptable. Cefpodoxime and cefdinir are U.S. FDA approved for 5 days of therapy; all other cephalosporins require 10 days of therapy.

f Erythromycin or clarithromycin is acceptable (10 days of therapy).

TABLE 6.2
Secondary Prevention of Recurrent Rheumatic Fever.
Modified from Gerber MA, Baltimore RS, Eaton CB, et al. Prevention of rheumatic fever and diagnosis and treatment of acute streptococcal pharyngitis: a scientific statement from the American Heart Association Rheumatic Fever, Endocarditis, and Kawasaki Disease Committee of the Council on Cardiovascular Disease in the Young, the Interdisciplinary Council on Functional Genomics and Translational Biology, and the Interdisciplinary Council on Quality of Care and Outcomes Research. Circulation 2009;119:1541-1551. Copyright © 2009 Lippincott Williams & Wilkins.
Drug Adults Children (≤27 kg)
Penicillin G benzathine 1.2 million units IM every 4 weeks (or every 3 weeks in high-risk situations) 600,000 units every 4 weeks a (or every 3 weeks in high-risk situations)
Penicillin V 500 mg twice daily 250 mg orally twice daily
Sulfadiazine 1000 mg orally once daily 500 mg orally once daily
For Patients Allergic to Penicillin and Sulfadiazine
Azithromycin 250 mg orally once daily b 5 mg/kg orally once daily (maximum 250 mg/day)
Duration of Secondary Prophylaxis (Whichever Is Longer) in Rheumatic Fever Patients
With carditis and residual valve disease (including after valve surgery): 10 years or until 40 years of age; sometimes lifelong
With carditis but no residual valve disease: 10 years or until 21 years of age
Without carditis: 5 years or until 21 years of age

a For small children and infants: 25,000 units/kg intramuscularly every 4 weeks (or every 3 weeks in high-risk situations).

b Macrolide susceptibility testing should be pursued before use of this drug class. Erythromycin is an acceptable alternative to azithromycin, although the latter has fewer adverse effects and permits once-daily dosing. Erythromycin dosing for adults: 250 mg orally twice daily. Erythromycin dosing for children: 20 mg/kg/day divided twice daily (maximum 500 mg/day).

There are gaps in the implementation of medical and surgical interventions of proven effectiveness for rheumatic heart disease in low- and middle-income countries. They include the suboptimal use of penicillin for secondary prophylaxis, inadequate monitoring and control of oral anticoagulant therapy, the dearth of reproductive services for women with rheumatic heart disease, and disparities in the use of percutaneous and surgical interventions between different countries.

Prevention of infective endocarditis

IE occurs when bacteremia results in bacterial adherence and proliferation at sites of platelet and fibrin deposition on disrupted endothelial surfaces. Patients with native or prosthetic VHD are at increased risk for IE due to endothelial disruption on the valve leaflets by high-velocity and turbulent blood flow patterns (see Chapter 22 ). About 50% of patients with endocarditis have underlying native valve disease, and endocarditis may precipitate the diagnosis of valve disease in a previously asymptomatic patient.

Prevention of bacterial endocarditis is based on short-term antibiotic therapy at times of anticipated bacteremia in patients who are at the highest risk for endocarditis. The American Heart Association and American College of Cardiology published revised guidelines for groups of patients at highest risk, the procedures for which IE prophylaxis is indicated ( Box 6.3 ), and the appropriate antibiotic regimens for dental procedures ( Table 6.3 ). Prophylaxis for other procedures should include antibiotics active against the most likely organisms, as detailed in the guidelines. Antibiotics also are recommended at the time of surgical implantation of prosthetic cardiac valves or other intracardiac material such as cardiac implantable electronic devices.

BOX 6.3
From Nishimura RA, Otto CM, Bonow RO, et al. 2017 AHA/ACC focused update of the 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 Clinical Practice Guidelines. J Am Coll Cardiol 2017;70:252-289.
Cardiac Conditions for Which Endocarditis Prophylaxis for Dental Procedures Is Reasonable

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