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Medical Management of Chronic Rheumatic Heart Disease Benzathine Penicillin G Secondary prophylaxis, the continuous administration of benzathine penicillin G in the form of three to four weekly intramuscular injections, remains fundamental to RHD management.56,57 It prevents ARF recurrences and halts the progression of RHD; in some circumstances, it also allows for resolution Although benzathine penicillin G is one of the oldest and cheapest antibiotics, being on the World Health Organization's list of essential medicines, there continues to be a worldwide shortage.58 Manufacturing and quality assurance protocols are lacking or insufficient.58 Secondary prophylaxis is best delivered as part of a comprehensive registrybased RHD prevention program.56 Yet in much of the world where RHD remains endemic, no such programs exist; consequently the overall delivery of long-term antibiotics to prevent ARF recurrences remains suboptimal.59 The recommended duration of secondary prophylaxis is detailed in Table 55.1 Table 55.1 Duration of Secondary Prophylaxis for Rheumatic Fever and Rheumatic Heart Disease Duration of Prophylaxis WHO Patient Category Recommendations56 ARF only For 5 years after the last attack, or until 18 years old (whichever is longer) ARF with carditis For 5 years after the last but no residual heart attack, or until age 18 years disease (whichever is longer) Mild RHD For 10 years after the last attack, or at least until age 25 years Moderate RHD For 10 years after the last attack, or at least until age 25 years Severe RHD, Lifelong including those who Australian Recommendations53 Minimum of 10 years after most recent episode of ARF or until age 21 years (whichever is longer) Minimum of 10 years after most recent episode of ARF or until age 21 years (whichever is longer) Minimum of 10 years after most recent episode of ARF or until age 21 years (whichever is longer) Continue until age 35 years Continue until age 40 years or longer AHA/ACC Recommendations39 5 years or until patient is 21 years old (whichever is longer) 10 years or until patient is age 21 years (whichever is longer) 10 years or until patient is age 40 years (whichever is longer) 10 years or until patient is age 40 years (whichever is longer) 10 years or until patient is age 40 years are postintervention (whichever is longer) ACC, American College of Cardiology; AHA, American Heart Association; ARF, acute rheumatic fever; RHD, rheumatic heart disease; WHO, World Health Organization Medical Management of Chronic Valve Disease Patients with asymptomatic chronic RHD generally do not benefit from heart failure medications.39 Although medical therapy for heart failure, for example diuretics, angiotensin-converting-enzyme (ACE) inhibitors, and β-blockers May ameliorate symptoms, there is no evidence that they change the natural history of chronic RHD in the setting of normal contractility.39 In patients with symptomatic valvar disease, cardiac medications have only a temporizing role in optimizing the hemodynamic profile prior to surgical intervention In this setting, there may be a requirement to combine medications with fluid restriction as well as inotropic and/or ventilatory support.39 Atrial Arrhythmias The onset of AF is frequently associated with abrupt worsening of pulmonary congestive symptoms and may lead to pulmonary edema and/or cardiogenic shock This is the consequence of a shortened diastolic filling time and loss of atrial systole, which result in increased left atrial pressure, pulmonary venous congestion, and low cardiac output Patients presenting with pulmonary edema or with hemodynamic instability require prompt electric cardioversion More stable patients can be treated with β-blockers, calcium channel blockers, or amiodarone if the former two agents cannot be used or were ineffective Intravenous digoxin is less effective but is useful in patients with low blood pressure or poor ventricular function.39,60 In stable patients, rate control is usually the strategy of choice, as maintenance of sinus rhythm is frequently difficult to achieve, given the degree of left atrial hypertension, dilatation and fibrosis in these patients Oral β-blockers or calcium channel antagonists are the drugs of choice The latter, however, should be avoided in patients with depressed ventricular (right or left) function Digoxin is reserved for patients in whom β-blockers or calcium channel antagonists are contraindicated or when the ventricular rate remains uncontrolled.39,60 Although AF is the most common atrial tachyarrhythmia encountered, a minority of patients may suffer from atrial tachycardia or atrial flutter Medical treatment is similar to that for AF, but radiofrequency ablation may be considered in refractory cases On the other hand, the role of radiofrequency ablation for AF complicating rheumatic MV disease is often limited to a concomitant procedure at the time of MV surgery Anticoagulation with a vitamin K antagonist is mandatory in patients with MV disease and AF or flutter, given their very high risk of stroke Patients with a prior embolic event or with a left atrial/left atrial appendage thrombus are also indicated for anticoagulation Anticoagulation may be also beneficial in patients with significant left atrial dilatation or spontaneous echo contrast, but there is currently insufficient evidence to make this recommendation Newer oral anticoagulants have not been studied in patients with rheumatic MV disease, and vitamin K antagonists remain the only approved anticoagulant in this subset of patients.39,60 Pregnancy and Anticoagulation Pregnancy is associated with a physiologic increase in cardiac output, which results in an exponential increase in gradients across stenotic valves as predicted from the Gorlin equation Pregnancy is also associated with an increase in heart rate, which reduces the diastolic filling time Collectively these changes lead to worsening of symptoms, and adequate heart rate control is crucial to avoid clinical deterioration This can be achieved with the use of β-blockers (preferably with selective β-1 action) or digoxin Restriction of physical activity and diuretics are often necessary to mitigate symptoms, but overdiuresis should be avoided to prevent placental hypoperfusion Pregnancy is also a hypercoagulable state; therefore meticulous anticoagulation in patients with AF/flutter is required Approved regimens include unfractionated heparin or low-molecular-weight heparin (with daily monitoring of factor Xa levels) in the first trimester followed by warfarin until the 35th week of gestation, then switching back to heparin until delivery Low-dose warfarin (