Rheumatic Heart Disease (RHD)

What is the immunological classification and the primary bacterial driver of chronic Rheumatic Heart Disease?

Type II antibody-mediated cytotoxic hypersensitivity reaction, Group A Streptococcal pharyngitis

Rheumatic Heart Disease is driven by a process called [...], where host antibodies generated against the streptococcal [...] cross-react with cardiac myosin and valvular endothelial cells.

molecular mimicry, M protein

List the 3 main environmental and socioeconomic risk factors that disproportionately drive the prevalence of Rheumatic Heart Disease in South Africa.

systemic poverty, domestic overcrowding, limited antibiotic access

Describe the classic triad of auscultatory findings that define severe, uncomplicated rheumatic mitral stenosis.

loud first heart sound, opening snap, low-pitched rumbling diastolic murmur loudest at the apex

Describe the murmur of rheumatic mitral regurgitation, including its type, location of maximum intensity, and classic direction of radiation.

harsh blowing pansystolic murmur, loudest at the apex, radiates directly to the left axilla

What physical sign on precordial palpation indicates the development of secondary right ventricular hypertrophy in a patient with advanced Rheumatic Heart Disease?

parasternal heave

List the 3 structural hallmarks seen during chronic low-grade tissue remodeling of the heart valves in chronic Rheumatic Heart Disease.

commissural fusion, thickening and shortening of chordae tendineae, dystrophic calcification

What are the 2 primary diagnostic components used to differentiate myxomatous Mitral Valve Prolapse from rheumatic mitral regurgitation on physical exam and history?

presence of a mid-systolic click with late-systolic murmur, absence of childhood rheumatic fever history or overcrowding risk factors

How does degenerative calcific valvular disease differ from Rheumatic Heart Disease regarding patient age, history, and echocardiographic calcification pattern?

occurs in geriatric patients, lacks a history of childhood streptococcal pharyngitis, calcification is isolated to the valve bases or annulus without commissural fusion

What is the first-line diagnostic investigation used to establish Rheumatic Heart Disease, and what is the gold-standard modality used to exclude left atrial appendage thrombi?

transthoracic echocardiography, transoesophageal echocardiography

State the diagnostic threshold for an Antistreptolysin O titer in adults that confirms a recent preceding Group A Streptococcal infection.

greater than 200 IU/mL

What measured valve orifice area value on echocardiography explicitly confirms severe mitral stenosis in a patient with Rheumatic Heart Disease?

1.5 cm² or less

Severe rheumatic mitral regurgitation is characterized by a regurgitant fraction threshold of [...] or a regurgitant volume threshold of [...] per beat.

50 percent or higher, 60 mL or greater

What specific electrocardiogram (ECG) finding indicates severe left atrial enlargement secondary to chronic rheumatic mitral stenosis?

broad notched P waves or p-mitrale

What is the definitive first-line secondary antibiotic prophylaxis regimen, including dose, route, and frequency, used to arrest progressive Rheumatic Heart Disease?

Benzathine Penicillin G 1.2 million units, deep intramuscular injection, strictly every 3 to 4 weeks

State the required duration for secondary penicillin prophylaxis in an RHD patient with uncomplicated disease versus one with severe, persistent structural valvular disease.

at least 10 years or until age 21 whichever is longer, until age 40 or lifelong

Why must all patients with Rheumatic Heart Disease who develop Atrial Fibrillation receive long-term anticoagulation with Warfarin over standard scoring models?

they carry an extreme risk of thromboembolic stroke from left atrial appendage mural thrombi

What is the target International Normalized Ratio (INR) threshold range that must be tightly maintained for an RHD patient on Warfarin anticoagulation therapy?

2.0 to 3.0

What are the 3 precise prerequisite anatomical and clinical criteria required before a patient can safely undergo a Percutaneous Mitral Balloon Valvotomy?

mitral valve area of 1.5 cm² or less, complete absence of left atrial thrombi, absence of significant subvalvular calcification

State the exact empirical antibiotic regimen and timing used to prevent infective endocarditis in an RHD patient undergoing a high-risk dental procedure.

Amoxicillin 2 g orally, strictly 30 to 60 minutes before the commencement of the procedure

For which 2 systemic procedural categories is infective endocarditis antibiotic prophylaxis explicitly not recommended or indicated in an RHD patient?

routine gastrointestinal procedures, routine genitourinary procedures

Sudden heart rate acceleration in a patient with severe rheumatic mitral stenosis can cause a catastrophic loss of diastolic filling time, precipitating which acute life-threatening complication?

acute pulmonary edema

On a two-dimensional transthoracic echocardiogram parasternal long-axis view, what classic structural restriction pattern is pathognomonic for the anterior mitral leaflet in RHD?

hockey-stick or doming configuration

Gross pathological visualization of an explanted rheumatic mitral valve from a superior atrial view reveals a classic slit-like aperture known as a [...] or [...] deformity.

fish-mouth, buttonhole

In an integrated MCQ vignette, a young patient from an overcrowded background presents with a low-pitched diastolic apical rumble and an irregular pulse; what are the 2 immediate next steps in management?

order a transthoracic echocardiogram, initiate Warfarin anticoagulation