Mitral regurgitation resident survival guide

❑ Most preferred

❑ Done in absence of papillary muscle necrosis

Acute mitral regurgitation

❑ In complex MR with extensive destruction

❑ Lateral LV wall motion abnormality

Reperfusion or revascularization:

❑ Early reperfusion for myocardial infarction can reduce localized LV remodeling and hence MR ❑ CABG or coronary angioplasty

Reperfusion or revascularization:

❑ For MR due to myocardial infarction ❑ CABG or coronary angioplasty

Cardiac transplantation:

❑ On some occasions with no contraindication for surgery
❑ In patients with severe LV dysfunction

Complete Diagnostic Approach to Mitral Regurgitation

A complete diagnostic approach should be carried out after a focused initial rapid evaluation is conducted and following initiation of any urgent intervention. Shown below is an algorithm summarizing the complete diagnostic approach to mitral regurgitation according to 2014 AHA/ACC guidelines for management of valvular heart disease.^[2].
Abbreviations: AF: Atrial fibrillation; MR: Mitral regurgitation; EKG: Electrocardiogram; EF: Ejection fraction; S1: First heart sound; S2: Second heart sound; S3: Third heart sound; LV: Left ventricle; MVP: Mitral valve prolapse

Characterize the symptoms:

Acute mitral regurgitation:

❑ Symptoms of shock and pulmonary edema:

❑ Shortness of breath

❑ Orthopnea

❑ Paroxysmal nocturnal dyspnea

❑ Cough

❑ Altered mental status

❑ Pedel edema

❑ Oliguria

❑ Cyanosis

❑ Pallor

❑ Diaphoresis

❑ Abdominal pain (may be suggestive of mesenteric ischemia)

❑ Symptoms suggestive of precipitating events:

❑ Chest pain (suggestive of myocardial ischemia)

❑ Fever (suggestive of infective endocarditis)

❑ Petechiae, Osler's nodes, Janeway lesions (suggestive of infective endocarditis)

Chronic mitral regurgitation:

❑ Asymptomatic

❑ Typical in isolated mild to moderate MR

❑ Severe MR until there is left ventricular failure, pulmonary hypertension or atrial fibrillation

❑ Symptoms associated with decreased forward flow and increased backflow across mitral valve:

❑ Exertional dyspnea

❑ Orthopnea

❑ Paroxysmal nocturnal dyspnea

❑ Exercise intolerance

❑ Fatigue

❑ Light-headedness

❑ Exertional syncope

❑ Exertional angina

❑ Cough

❑ Symptoms associated with complications:

❑ Palpitations (suggestive of atrial fibrillation)

❑ Hoarseness (recurrent laryngeal nerve compression due to left atrium enlargement)

❑ Fever (suggestive of infective endocarditis)

❑ Stroke (suggestive of thromboembolism)

❑ Hemoptysis (suggestive of thromboembolism)

❑ Flank pain and hematuria (suggestive of septic emboli or glomerulonephritis)

❑ Seizures (suggestive of thromboembolism)

❑ Symptoms of right heart failure:

❑ Ascites

❑ Pedel edema

❑ Abdominal pain (hepatomegaly)

❑ Other etiology associated symptoms:

❑ Joint pains (suggestive of rheumatic etiology)

❑ Skin lesions (suggestive of rheumatic etiology)

Obtain a detailed history:

❑ Past medical history:

❑ Congenital heart disease

❑ Rheumatic heart disease

❑ Ischemic heart disease

❑ Valvular heart disease

❑ Cardiomyopathy

❑ Cardiac surgery

❑ Hypertension

❑ Diabetes mellitus

❑ Radiation exposure

❑ Collagen vascular disease

❑ Chest trauma

❑ Family history:

❑ Valvular heart disease

❑ Medications:

❑ Anorectic drug combinations

❑ Ergotamine

❑ Pergolide

❑ Cabergoline

Examine the patient:

Vital signs:
❑ Pulse

❑ Rapid and thready (in acute MR)

❑ Low volume with brisk upstroke (in chronic MR)

❑ Irregularly irregular pulse (with onset of AF)

❑ Blood pressure

❑ Hypotension (in acute MR)

❑ Normotensive (in chronic MR with preserved ejection fraction)

❑ Temperature

❑ Fever (suggestive of infective endocarditis)

❑ Respiratory rate

❑ Tachypnea (typical)

Skin:
❑ Cool and clammy (in cardiogenic shock)
❑ Cyanosis
❑ Peripheral edema (suggestive of right heart failure)

Cardiovascular system:
Palpation:
❑ Apical impulse

❑ Leftward displacement (in chronic MR due enlargement of the left ventricle)

❑ Hyperdynamic but in normal location (in acute MR)

❑ Thrill (in acute MR and severe chronic MR)
❑ Elevated jugular venous pulse

❑ Sign of elevated right sided pressure

❑ Seen in acute MR and severe chronic MR

Auscultation:
❑ Heart sounds

❑ S1 is diminished (suggestive of MR)

❑ Wide splitting of S2 (low forward flow causing early A2)

❑ Loud and delayed P2 (suggestive of pulmonary hypertension)

❑ New S3 (suggestive of left ventricular dilation)

❑ Murmur

❑ High pitched and blowing holosystolic murmur (typical)

❑ Best heard over the apex radiating to the axilla and back

❑ Starts after S1 and continues up to and sometime beyond and obscuring A2

❑ Other types of murmur

❑ Silent (in cases of acute MR)

❑ Mid to late systolic murmur (in case of papillary muscle prolapse)

❑ Early diastolic murmur (due to large diastolic flow across severe MR)

❑ Mid systolic click (suggestive of mitral valve prolapse)

Respiratory system:
❑ Crackles or rales (suggestive of pulmonary edema)
❑ Tachypnea

Abdominal system:
❑ Hepatojugular reflex
❑ Hepatomegaly
❑ Ascites

Neurological system:
❑ Stroke (in case of thromboembolism)

Order electrocardiogram (urgent):

❑ In acute MR

❑ Mostly normal

❑ Findings of myocardial infarction

❑ In chronic MR

❑ Findings of left ventricular hypertrophy with strain

❑ Findings of left atrial enlargement

❑ Findings of pulmonary hypertension

❑ Findings of atrial fibrillation complication

Left atrial enlargement produces a broad, bifid P wave in lead II (**P mitrale**)

Order chest X-ray (urgent):

❑ Acute MR

❑ Normal size cardiac silhouette

❑ Signs of pulmonary edema

❑ Chronic MR

❑ Cardiomegaly

❑ Signs of pulmonary edema if left ventricle fails

❑ Calcification of the mitral valve annulus

Calcification of the mitral annulus around the margins of the posterior leaflet forming a “C”

Order transthoracic echocardiography (TTE) (urgent):

❑ Confirmatory
❑ To determine severity and assess hemodynamic consequences
❑ To establish etiology
❑ To determine prognosis and evaluate for timing of intervention

Order lab tests:

❑ CBC
❑ Electrolytes
❑ ESR
❑ Serum cardiac troponin I and T
❑ Creatine kinase (CK-MB)
❑ Serum urea and creatinine

Other tests

❑ Transesophageal echocardiography (TEE if TTE is equivocal)
❑ Cardiac catheterization:

❑ In stable acute MR to detect coronary obstruction

❑ To assess hemodynamic status in symptomatic patients when noninvasive tests are inconclusive

❑ To assess the severity when there is discrepancy between noninvasive testing and physical examination

❑ Exercise testing:

❑ Done in asymptomatic severe MR

❑ To confirm the absence of symptoms

❑ To assess the hemodynamic response to exercise

❑ Cardiac MRI

❑ To assess severity when there is a discrepancy between clinical findings and echocardiography

Cardinal findings that are suggestive of acute mitral regurgitation

❑ Sudden onset and rapid progression of pulmonary edema
❑ Signs and symptoms of cardiogenic shock
❑ Silent to holosystolic murmur on auscultation
❑ Normal ECG
❑ Normal size cardiac silhouette on chest X-ray
❑ Echocardiography findings:

❑ Acute severe mitral regurgitation

❑ Normal left ventricular size

❑ Reduced EF

❑ Ruptured mitral chordae tendinae (flail leaflet)

❑ Ruptured papillary muscle

Cardinal findings that are suggestive of chronic mitral regurgitation

❑ Asymptomatic to chronic symptoms
❑ Pre-existing heart disease
❑ Classic holosystolic murmur on auscultation
❑ ECG findings of left ventricular hypertrophy with strain and left atrial enlargement
❑ Cardiomegaly on chest X-ray
❑ Echocardiography findings:

❑ Mitral regurgitation

❑ Left ventricular dilation

❑ Preserved to decreased EF

Mitral valve anatomy

Normal

Abnormal

Chronic primary mitral regurgitation

Chronic secondary mitral regurgitation

Treatment

Treatment of Acute Mitral Regurgitation

Shown below is an algorithm summarizing the approach to the management of acute mitral regurgitation.^[1]^[2].
Abbreviations: IE: Infective endocarditis; LV: Left ventricle; LVEF: Left ventricular ejection fraction; MR: Mitral regurgitation;

Assess if the patient is hemodynamically stable?

❑ Hemodynamic instability

❑ Hypotension

❑ Cold extremities

❑ Peripheral cyanosis

❑ Altered mental status

Yes
(unstable)

No
(stable)

Initial resuscitative measures:

❑ Secure airway
❑ O2
❑ 2 wide bore IV access
❑ Arterial line
❑ ECG monitor
❑ Monitor vitals continuously
❑ ICU admission

Initiate medical therapy:

❑ Vasodilator therapy: IV nitroprusside
AND
❑ Inotropic agents: IV dobutamine

Consider the following:

❑ Mechanical ventilation

❑ Pulmonary artery catheterization

Initial resuscitative measures:

❑ O2
❑ 2 wide bore IV access
❑ Monitor vitals continuously

Initiate medical therapy:

❑ Vasodilator therapy: IV nitroprusside

Ischemic mitral regurgitation

Non-ischemic mitral regurgitation

MR due to heart failure exacerbation(functional MR)

MR due to IE (organic MR)

Initiate medical therapy:

❑ In cases of reduced LVEF (ischemic cardiomyopathy)
❑ Medications:

❑ Angiotensin converting enzyme inhibitors

❑ Angiotensin II receptor blockers

Intra-aortic balloon pump:

❑ To improve forward cardiac output
❑ To reduce the impact on regurgitant volume

Reperfusion or revascularization:

❑ CABG or coronary angioplasty
❑ Early reperfusion can reduce localized LV remodeling and hence MR

Mitral valve surgery:

❑ Papillary muscle rupture
❑ Moderate to severe ischemic MR who are undergoing CABG
❑ Mitral valve repair:

❑ Most preferred

❑ Done in absence of papillary muscle necrosis

❑ In complex MR with extensive destruction

❑ Lateral LV wall motion abnormality

Cardiac transplantation:

❑ On some occasions with no contraindication for surgery
❑ In patients with severe LV dysfunction

Heart failure management:

❑ Click here for acute heart failure resident survival guide

❑ ACE inhibitors or (ARBs) if LVEF is ≤ 40%

❑ Intravenous inotropic drugs (dobutamine)

❑ Diuretic therapy

❑ IV vasodilators

Mitral valve surgery:

❑ When there is no response to medical management

❑ Mitral valve replacement or mitral valve repair

Initiate medical therapy:

❑ Click here for infective endocarditis resident survival guide and antimicrobial treatment

Mitral valve surgery:

❑ Urgent surgery:

❑ Persistent heart failure

❑ Pulmonary hypertension

❑ Early mitral valve closure

❑ Mostly done

❑ Due to extensive tissue destruction

❑ If less mitral valve destruction

Treatment of Chronic Mitral Regurgitation

Chronic Primary Mitral Regurgitation

Shown below is an algorithm summarizing the approach to the management of chronic primary mitral regurgitation.^[2].
Abbreviations: AF: Atrial fibrillation; IE: Infective endocarditis; LVEF: Left ventricular ejection fraction; LVESD: Left ventricular end systolic dimension; MR: Mitral regurgitation; MVP: Mitral valve proplapse; PASP: Pulmonary artery systolic pressure; RHD: Rheumatic heart disease

Chronic primary mitral regurgitation

Severe MR:

❑ Etiologies:

❑ Severe MVP with loss of coaptation

❑ RHD with loss of central coaptation

❑ Prior IE

❑ Radiation induced leaflet thickening

❑ Left ventricular dilation
❑ Regurgitation fraction ≥ 50%
❑ Regurgitation volume ≥ 60ml
❑ Effective regurgitation orifice ≥ 0.4cm²
❑ Vena contracta ≥ 0.7cm

Progressive MR (Stage B):

❑ Etiologies:

❑ Severe MVP with normal coaptation

❑ RHD with loss of central coaptation

❑ Prior IE

❑ No Left ventricular dilation
❑ Regurgitation fraction < 50%
❑ Regurgitation volume < 60ml
❑ Effective regurgitation orifice < 0.4cm²
❑ Vena contracta < 0.7cm

Symptomatic (Stage D)

Asymptomatic (Stage C)

Initiate medical therapy:

❑ Vasodialators:

❑ Intravenous nitroprusside

❑ Hydralazine

❑ Beta blocker
❑ Diuretics
❑ Calcium channel blocker

Mitral valve surgery:

❑ Mostly preferred

❑ Initiate infective endocarditis antimicrobial prophylaxis after mitral valve surgery

❑ Mechanical valve in patients <65 years who have long-standing AF

❑ Bioprosthetic valves in patients with contraindications to warfarin

Revascularisation:

❑ Concurrent coronary artery disease
❑ Revascularized at the time of mitral valve surgery

Anticoagulation therapy:

❑ Warfarin:

❑ Target INR 2.5 (range 2.0 to 3.0)

❑ Rheumatic mitral valve disease who have a history of systemic embolism

❑ Left atrial thrombus

❑ Paroxysmal or chronic atrial fibrillation

❑ Aspirin:

❑ 75 to 100 mg/day

❑ Recurrent embolism despite adequate anticoagulation

Endocarditis prophylaxis:

Mitral valve surgery:

❑ Performed in the following patients:

❑ LVEF 30 to ≤60% OR LVESD ≥ 40mm (Stage C2)

❑ LVEF >60% AND LVESD < 40mm (Stage C1)

❑ With likelihood of successful repair > 95%

❑ With expected mortality < 1%

❑ New onset AF OR PASP > 50mmHg (Stage C1)

❑ With likelihood of successful repair > 95%

❑ With expected mortality < 1%

❑ Mostly preferred

❑ Mechanical valve in patients <65 years who have long-standing AF

❑ Bioprosthetic valves in patients with contraindications to warfarin

Revascularization:

❑ Concurrent coronary artery disease
❑ Revascularized at the time of mitral valve surgery

Periodic monitoring:

❑ In stage C1 patients with the following:

❑ With likelihood of successful repair < 95%

❑ With expected mortality > 1%

❑ Clinical evaluation:

❑ Every 3-6 months

❑ Initiate infective endocarditis antimicrobial prophylaxis for patients undergoing mitral valve surgery

❑ Every 6 months

Anticoagulation therapy:

❑ Warfarin:

❑ Target INR 2.5 (range 2.0 to 3.0)

❑ Rheumatic mitral valve disease who have a history of systemic embolism

❑ Left atrial thrombus

❑ Paroxysmal or chronic atrial fibrillation

❑ Aspirin:

❑ 75 to 100 mg/day

❑ Recurrent embolism despite adequate anticoagulation

Endocarditis prophylaxis:

Periodic monitoring:

❑ Clinical evaluation:

❑ Every 3-6 months

❑ Every 6 months

Anticoagulation therapy:

❑ Warfarin:

❑ Target INR 2.5 (range 2.0 to 3.0)

❑ Rheumatic mitral valve disease who have a history of systemic embolism

❑ Left atrial thrombus

❑ Paroxysmal or chronic atrial fibrillation

❑ Aspirin:

❑ 75 to 100 mg/day

❑ Recurrent embolism despite adequate anticoagulation

Chronic Secondary Mitral Regurgitation

Shown below is an algorithm summarizing the approach to the management of chronic secondary mitral regurgitation.^[2].

Abbreviations: AF: Atrial fibrillation; CAD: Coronary artery disease; HF: Heart failure; IE: Infective endocarditis; LV: Left ventricle; MR: Mitral regurgitation

Chronic secondary mitral regurgitation

Heart failure treatment:

❑ Click here for heart failure resident survival guide

❑ ACE inhibitors

❑ ARBs

❑ Intravenous inotropic drugs (dobutamine)

❑ Diuretictherapy

❑ IV vasodilators

CAD treatment:

❑ Click here for coronary artery disease medical therapy

❑ Aspirin

❑ ACE inhibitors

❑ Coronary angiography
❑ Click here for revascularization therapy

Cardiac resynchronization therapy:

❑ Cardiac resynchronization therapy with biventricular pacing:

❑ In functional MR patients with ventricular dyssynchrony

❑ Reduce LV end-systolic and end-diastolic dimensions

❑ Reduce mitral regurgitant jet area

Severe MR:

❑ Echo findings:

❑ Regional wall motion abnormalities with severe tethering of mitral leaflet

❑ Annular dilation with severe loss of central coaptation of the mitral leaflets

❑ LV dilation and systolic dysfunction due to primary myocardial disease
❑ Regurgitation fraction ≥ 50%
❑ Regurgitation volume ≥ 30ml
❑ Effective regurgitation orifice ≥ 0.2 cm²

Progressive MR (Stage B):

❑ Echo findings:

❑ Regional wall motion abnormalities with mild tethering of mitral leaflet

❑ Annular dilation with mild loss of central coaptation of the mitral leaflets

❑ LV dilation and systolic dysfunction due to primary myocardial disease
❑ Regurgitation fraction < 50%
❑ Regurgitation volume < 30ml
❑ Effective regurgitation orifice < 0.2 cm²

Stage D: Symptomatic (HF symptoms due to MR persist even after revascularization and medical therapy)

Stage C: Asymptomatic (HF and coronary ischemia symptoms respond to revascularization and medical herapy)

HF and coronary ischemia symptoms respond to revascularization and medical herapy

Mitral valve surgery:

❑ Mostly preferred

❑ Initiate infective endocarditis antimicrobial prophylaxis

❑ Mechanical valve in patients <65 years who have long-standing AF

❑ Bioprosthetic valves in patients with contraindications to warfarin

Anticoagulation therapy:

❑ Warfarin:

❑ Target INR 2.5 (range 2.0 to 3.0)

❑ History of systemic embolism

❑ Left atrial thrombus

❑ Paroxysmal or chronic atrial fibrillation

❑ Aspirin:

❑ 75 to 100 mg/day

❑ Recurrent embolism despite adequate anticoagulation

Endocarditis prophylaxis:

Periodic monitoring:

❑ Clinical evaluation:

❑ Every 3-6 months

❑ Every 6 months

Mitral valve surgery:

❑ Only in patients undergoing other cardiac surgery
❑ Mitral valve repair:

❑ Mostly preferred

❑ Initiate infective endocarditis antimicrobial prophylaxis for patients undergoing mitral valve surgery

❑ Mechanical valve in patients <65 years who have long-standing AF

❑ Bioprosthetic valves in patients with contraindications to warfarin

Anticoagulation therapy:

❑ Warfarin:

❑ Target INR 2.5 (range 2.0 to 3.0)

❑ History of systemic embolism

❑ Left atrial thrombus

❑ Paroxysmal or chronic atrial fibrillation

❑ Aspirin:

❑ 75 to 100 mg/day

❑ Recurrent embolism despite adequate anticoagulation

Endocarditis prophylaxis:

Periodic monitoring:

❑ Clinical evaluation:

❑ Every 3-6 months

❑ Every 6 months

Mitral valve surgery:

❑ Only in patients undergoing other cardiac surgery
❑ Mitral valve repair:

❑ Mostly preferred