Mitral Regurgitation (MR)

What is Mitral Regurgitation (MR) according to the summary?

The leakage of blood from the left ventricle into the left atrium due to incomplete closure of the mitral valve during systole. Summary 1

How is Mitral Regurgitation (MR) categorized according to the summary?

Categorized according to onset (acute vs. chronic forms) and etiology (primary vs. secondary). Summary / Definitions 2

What is the difference between primary and secondary Mitral Regurgitation (MR)?

Primary MR involves the mitral valve structure itself, whereas secondary MR results from other pathologies (e.g., cardiomyopathy) causing valvular incompetence. Summary / Etiology 3

What are examples of causes for ischemic Mitral Regurgitation (MR) mentioned in the summary?

Ischemic MR can be acute (e.g., papillary muscle rupture in MI) or chronic (in coronary artery disease). Summary / Etiology 4

How do symptoms differ between acute and chronic Mitral Regurgitation (MR) according to the summary?

Acute MR can present with cardiogenic shock and flash pulmonary edema; chronic MR may have milder symptoms like cough and dyspnea. Summary / Clinical 5

What is the diagnostic modality of choice for Mitral Regurgitation (MR)?

Echocardiography is the diagnostic modality of choice. Summary / Diagnosis 6

What is the definitive treatment for primary Mitral Regurgitation (MR) according to the summary?

The definitive treatment in primary MR is surgical repair or valve replacement. Summary / Treatment 7

What is the mainstay of therapy for secondary Mitral Regurgitation (MR) according to the summary?

Therapy of the underlying condition (e.g., PCI in coronary artery disease) is the mainstay of therapy in secondary MR. Summary / Treatment 8

What is the aim of pharmacological treatment for Mitral Regurgitation (MR) according to the summary?

Pharmacological treatment aims to reduce the degree of heart failure. Summary / Treatment 9

What causes primary (organic) Mitral Regurgitation (MR)?

Primary MR is caused by direct involvement of the valve leaflets or chordae tendinae. Etiology 10

List three causes of primary (organic) Mitral Regurgitation (MR).

Degenerative disease (MVP, MAC, ruptured chordae), rheumatic fever, infective endocarditis, or ischemic MR (papillary muscle rupture post-MI). (Any 3) Etiology 11

What causes secondary (functional) Mitral Regurgitation (MR)?

Secondary MR is caused by changes of the left ventricle that lead to valvular incompetence. Etiology 12

List two causes of secondary (functional) Mitral Regurgitation (MR).

Coronary artery disease or prior MI causing papillary muscle involvement, or dilated cardiomyopathy (e.g., peripartum cardiomyopathy) and left-sided heart failure. (Any 2) Etiology 13

What is the immediate pathophysiological consequence of acute Mitral Regurgitation (MR)?

Increased left atrial volume with normal LA compliance and increased LV end-diastolic volume leads to a rapid increase in LA and pulmonary pressures causing pulmonary edema. Pathophysiology 14

How does the heart initially compensate for chronic Mitral Regurgitation (MR)?

Progressive dilation of the LV (eccentric hypertrophy) increases volume capacity, allowing preload/afterload to normalize initially and maintaining stroke volume (normal EF). Pathophysiology 15

What happens during the decompensated phase of chronic Mitral Regurgitation (MR)?

Progressive LV enlargement and myocardial dysfunction lead to decreased stroke volume, increased end-systolic/diastolic volumes, increased LA/LV pressure, and pulmonary congestion/HTN. Pathophysiology 16

What are the typical signs and symptoms of acute Mitral Regurgitation (MR)?

Dyspnea, symptoms/signs of left-sided heart failure and pulmonary edema (crackles), potentially cardiogenic shock (hypotension, poor perfusion), and palpitations. Clinical Features 17

Describe the typical murmur of acute Mitral Regurgitation (MR).

A soft, decrescendo systolic murmur (or potentially no murmur in severe cases with LV dysfunction/hypotension). Clinical Features 18

What symptoms characterize chronic Mitral Regurgitation (MR)?

Dyspnea (including exertional), dry cough, fatigue, palpitations, and symptoms of left-sided (and potentially right-sided) heart failure. Clinical Features 19

Describe the classic murmur of chronic Mitral Regurgitation (MR).

Holosystolic, high-pitched, blowing murmur heard best over the apex, radiating to the left axilla. Clinical Features 20

What maneuvers increase the intensity of the chronic Mitral Regurgitation (MR) murmur?

Maneuvers that increase preload (e.g., leg raise) or afterload (e.g., handgrip). Clinical Features 21

What associated heart sounds might be heard in chronic Mitral Regurgitation (MR)?

A quiet S1 heart sound and an S3 heart sound in advanced stages. Clinical Features 22

What physical exam finding related to the point of maximal impulse (PMI) occurs in chronic MR?

Lateral displacement of the apical impulse. Clinical Features 23

What does Stage C Mitral Regurgitation (MR) represent according to AHA staging?

Asymptomatic severe MR. Classification 24

How is Stage C primary Mitral Regurgitation (MR) further divided based on LV function/size?

C1: LVEF > 60% and LVESD < 40 mm. C2: LVEF ≤ 60% and/or LVESD ≥ 40 mm. Classification 25

What does Stage D Mitral Regurgitation (MR) represent according to AHA staging?

Severe symptomatic MR. Classification 26

What is the diagnostic modality of choice for the initial assessment of Mitral Regurgitation (MR)?

Transthoracic echocardiography (TTE). Diagnosis 27

When is Transesophageal echocardiography (TEE) indicated for Mitral Regurgitation (MR)?

Indicated prior to surgery or if TTE findings are inadequate for diagnostic workup. Diagnosis 28

How does left atrial size typically differ between acute and chronic Mitral Regurgitation (MR) on echo?

In acute MR, the left atrium is typically normal size. In chronic MR, the left atrium is typically dilated. Diagnosis 29

How does left ventricular size typically differ between acute and chronic Mitral Regurgitation (MR) on echo?

In acute MR, the left ventricle size is typically normal. In chronic MR, the left ventricle is typically increased/remodeled (dilated). Diagnosis 30

How does LVEF typically differ between acute and chronic (compensated vs. decompensated) MR on echo?

Acute MR: normal LVEF. Chronic compensated MR: normal or increased LVEF. Chronic decompensated MR: decreased LVEF. Diagnosis 31

Why might BNP levels be normal in acute Mitral Regurgitation (MR)?

BNP levels are typically normal because of the acute onset of symptoms, not allowing time for significant elevation. Diagnosis 32

What ECG findings might suggest chronic Mitral Regurgitation (MR)?

Signs of left ventricular hypertrophy (LVH), P mitrale (LA enlargement), or atrial fibrillation. Signs of right heart strain (P pulmonale) may occur in later stages. Diagnosis 33

What might a chest x-ray show in acute or decompensated chronic Mitral Regurgitation (MR)?

Signs of pulmonary congestion or pulmonary edema. Diagnosis 34

What might a chest x-ray show specifically in chronic Mitral Regurgitation (MR)?

Signs of LV enlargement (laterally displaced border) and LA enlargement (straightening of left border, double density sign); possibly annular calcification. Diagnosis 35

What is the general principle for managing acute primary Mitral Regurgitation (MR)?

All patients should undergo urgent surgical repair or valve replacement. Treatment 36

What medical therapies are used as a temporizing measure for acute Mitral Regurgitation (MR) while awaiting surgery?

Management of acute heart failure symptoms with vasodilators (nitroprusside, nitrates) to reduce afterload and diuretics (furosemide) for pulmonary edema. Treatment 37

What bridging devices might be used for patients with acute Mitral Regurgitation (MR) deteriorating despite medical therapy?

Intra-aortic balloon pump (IABP); consider Left Ventricular Assist Device (LVAD) or ECMO in refractory cases. Treatment 38

What is the preferred surgical option for acute primary Mitral Regurgitation (MR), and why?

Valve repair is the preferred option because of the reduced risk of mortality and complications compared to replacement. Treatment 39

What guides the management of chronic Mitral Regurgitation (MR)?

Management is guided by symptoms, extent of heart failure, and the cause of MR (primary vs. secondary). Treatment 40

What medical therapies are used for heart failure management in chronic Mitral Regurgitation (MR)?

Diuretics (e.g., furosemide), ACE inhibitors (e.g., lisinopril), and beta blockers (e.g., metoprolol tartrate). Treatment 41

When is surgery indicated for severe chronic primary Mitral Regurgitation (MR)?

Indicated if symptomatic (irrespective of LV function) OR if asymptomatic with LV systolic dysfunction (LVEF ≤ 60% and/or LVESD ≥ 40 mm). Treatment 42

When is surgery considered for severe chronic secondary Mitral Regurgitation (MR)?

Consider for patients with persistent symptomatic heart failure (NYHA classes III-IV) despite optimal medical management. Treatment 43

What are the major complications associated with Mitral Regurgitation (MR)?

Heart failure, pulmonary edema, cardiogenic shock, atrial fibrillation (increasing stroke risk), endocarditis, and pulmonary artery hypertension. Complications 44