❤️ What Is Mitral Regurgitation?
Mitral regurgitation is a state where the mitral valve of the heart does not close completely. When healthy, the mitral valve closes the moment the left ventricle contracts during a heartbeat, ensuring all oxygenated blood flows into the aorta. When mitral regurgitation occurs, the valve doesn't close completely, and some blood flows back into the left atrium — resulting in less blood reaching the aorta and the body's organs.
🏥 Causes of Mitral Regurgitation
Mitral regurgitation is typically a condition caused by underlying factors. We can differentiate chronic and acute mitral regurgitation.
Chronic causes:
- Rheumatic fever affecting the heart
- Degenerative lesions of the mitral valve (e.g., due to hypertension)
- Connective tissue disorders — Marfan's syndrome, Ehlers-Danlos syndrome, SLE
- Infective endocarditis
- Coronary artery disease
- Cardiomyopathies
- Genetic predispositions
- Drugs (e.g., ergotamine)
Acute causes:
- Infective endocarditis
- Injuries (e.g., during an intravenous procedure)
- Acute myocardial infarction
- Sudden exacerbation of chronic causes
🩺 Mitral Regurgitation Symptoms
Some mitral regurgitations show no symptoms and are found incidentally on echocardiography. Symptoms may include:
- Physical activity intolerance or easy tiredness
- Shortness of breath
- Heart palpitations or fast heartbeat
- Heart murmurs (heard with a stethoscope)
📸 What Does Mitral Regurgitation Look Like on ECHO?
On echocardiogram, mitral regurgitation shows:
- Regurgitant jet — the wave coming back into the left atrium (primary sign)
- Orifice in the mitral valve area — cusps not touching tightly
- The cause — vegetation, papillary muscle lesions, or chordae tendineae issues
- Aftereffects — heart disease or left ventricle remodeling
🧮 How to Use the EROA Calculator
From your ECHO examination, enter 4 parameters:
- Radius (r) — PISA radius in cm
- Aliasing velocity (Va) — in cm/s
- Max velocity (Vmax) — peak velocity of MR jet in cm/s
- VTI — velocity time integral of the MR jet in cm
The calculator computes:
EROA = VFR / Vmax
Rvol = EROA × VTI
📊 Degrees of Mitral Regurgitation — Grades A, B, C, D
| Grade | Stage | EROA | Rvol | Symptoms |
|---|---|---|---|---|
| A | At risk | — | — | None |
| B | Progressive | < 0.4 cm² | < 60 mL | None |
| C | Asymptomatic severe | ≥ 0.4 cm² | ≥ 60 mL | None |
| D | Symptomatic severe | ≥ 0.4 cm² | ≥ 60 mL | Yes |
❓ FAQs
What is the most common cause of mitral regurgitation?
The most common cause is mitral valve prolapse — the cusps (leaflets) bulge into the left atrium during heart contraction. It's fairly common and most people live their lives without even knowing about it.
How do I calculate EROA on ECHO?
- Find the PISA radius (r) and aliasing velocity (Va) on ECHO.
- Calculate VFR = 2π × r² × Va.
- Find Vmax on ECHO.
- EROA = VFR / Vmax.
How common is mitral regurgitation?
Up to 70% of adults may have some degree of mitral regurgitation. Most have trace, asymptomatic insufficiency. Significant (moderate to severe) MR occurs in 3–10% of the general population.
How do you treat mitral regurgitation?
The best treatment is cardiac surgery — repair or total replacement of the mitral valve. Medications can alleviate symptoms and treat underlying causes, but they cannot fix the mechanical defect of the valve.
🔄 Is Both Mitral and Tricuspid Regurgitation Possible?
Yes, it is possible to have both valve defects simultaneously. This is more common in patients with ischemic mitral valve regurgitation and those with rheumatic fever. Usually mitral regurgitation appears first, followed by tricuspid issues months or years later. The prognosis is poor, often leading to heart failure.