MioAtlas
G1: Left-sided valves

Mitral annular calcification

Chronic non-inflammatory degenerative process characterized by deposition of calcium and lipids in mitral fibrous annulus (predominantly in posterior annulus).

Open in 3D simulator

Definition

Chronic non-inflammatory degenerative process characterized by deposition of calcium and lipids in the mitral fibrous annulus (predominantly in posterior annulus), which can extend to base of mitral leaflets limiting their diastolic excursion and producing increased transmitral gradients and/or mitral regurgitation without commissural fusion [V1] [G1-09].

Severity criteria

  • Single grade (Degenerative / Typical, Ú):
    • Calcified posterior annular thickness > 4–5 mm with marked echocardiographic hyperreflectivity and posterior acoustic shadowing [G1-09].
    • Mean transmitral gradient: typically 2–5 mmHg (in severe forms with luminal encroachment can reach 6–8 mmHg) [G1-09] [V1].
    • Associated mitral regurgitation: usually Mild (EROA < 0.20 cm², RV < 30 mL) or Moderate (EROA 0.20–0.39 cm²) [V1] [V3].
    • Absence of mitral commissural fusion (fundamental differentiation from rheumatic etiology) [V1] [G1-09].

Findings by layer

Hemodynamics

  • Mean transmitral gradient: Mild to moderate increase (2–5 mmHg) dependent on heart rate and degree of annular protrusion [G1-09].
  • Left atrial pressure: Normal or mildly elevated at rest, with disproportionate elevation during tachycardia or exertion [G1-09] [V1].

Rhythm

  • Normal sinus rhythm or atrial fibrillation frequent in older adults due to left atrial dilation and advanced age [V1] [G1-09].
  • Risk of AV or intraventricular conduction blocks due to calcium extension into conduction system of fibrous trigone [E2] [G1-09].

ECG

  • Left atrial enlargement, atrial fibrillation, or atrioventricular / intraventricular conduction disturbances [E1] [E2].

Heart sounds and murmurs

  • First heart sound (S1): Normal or mildly muffled (not accentuated as in rheumatic stenosis) [G1-10].
  • Opening snap (OS): ABSENT (absence of commissural fusion and preserved free-edge mobility prevents generation of opening snap) [G1-09] [G1-15].
  • Diastolic rumble: Weak and soft at apex if mean gradient is elevated [G1-09] [G1-15].
  • Systolic murmur: Apical holosystolic murmur of moderate mitral regurgitation or regurgitation due to malcoaptation secondary to posterior annular rigidity [G1-14] [V3].

Arterial pulse

  • Generally normal, or with signs of systemic arterial stiffness typical of advanced age [B4].

Jugular venous pulse

  • Normal, unless accompanying congestive heart failure [B3].

Maneuvers

  • Isometric handgrip: Increases mitral regurgitation murmur intensity [B1].
  • Valsalva: Decreases systolic murmur intensity [B1].

Simulator severity grades

Simulator severity grades: Single grade
Baseline rhythm: Normal Sinus Rhythm

Also known as: Mitral annular calcification · Calcification of the mitral annulus · Mitral ring calcification · MAC

Other pathologies in this group

Sources

  1. [B1] Bedside diagnosis of systolic murmurs . N Engl J Med (1988) . DOI: 10.1056/NEJM198806163182404 PubMed: 2897627
  2. [B3] The jugular venous pressure revisited . Cleve Clin J Med (2013) . DOI: 10.3949/ccjm.80a.13039 PubMed: 24085809
  3. [B4] The Carotid Pulse . Clinical Methods: The History, Physical, and Laboratory Examinations (1990) . PubMed: 21250154
  4. [E1] AHA/ACCF/HRS recommendations for the standardization and interpretation of the electrocardiogram: part V: electrocardiogram changes associated with cardiac chamber hypertrophy: a scientific statement from the American Heart Association Electrocardiography and Arrhythmias Committee, Council on Clinical Cardiology; the American College of Cardiology Foundation; and the Heart Rhythm Society: endorsed by the International Society for Computerized Electrocardiology . Circulation (2009) . DOI: 10.1161/CIRCULATIONAHA.108.191097 PubMed: 19228820
  5. [E2] AHA/ACCF/HRS recommendations for the standardization and interpretation of the electrocardiogram: part III: intraventricular conduction disturbances: a scientific statement from the American Heart Association Electrocardiography and Arrhythmias Committee, Council on Clinical Cardiology; the American College of Cardiology Foundation; and the Heart Rhythm Society: endorsed by the International Society for Computerized Electrocardiology . Circulation (2009) . DOI: 10.1161/CIRCULATIONAHA.108.191095 PubMed: 19228822
  6. [G1-09] Management of Patients With Severe Mitral Annular Calcification: JACC State-of-the-Art Review . J Am Coll Cardiol (2022) . DOI: 10.1016/j.jacc.2022.06.009 PubMed: 35953138
  7. [G1-10] The First Heart Sound . Clinical Methods: The History, Physical, and Laboratory Examinations (1990) . PubMed: 21250175
  8. [G1-14] Systolic Murmurs . Clinical Methods: The History, Physical, and Laboratory Examinations (1990) . PubMed: 21250186
  9. [G1-15] Diastolic Murmurs . Clinical Methods: The History, Physical, and Laboratory Examinations (1990) . PubMed: 21250187
  10. [V1] 2025 ESC/EACTS Guidelines for the management of valvular heart disease . Eur Heart J (2025) . DOI: 10.1093/eurheartj/ehaf194 PubMed: 40878295
  11. [V3] Recommendations for Noninvasive Evaluation of Native Valvular Regurgitation: A Report from the American Society of Echocardiography Developed in Collaboration with the Society for Cardiovascular Magnetic Resonance . J Am Soc Echocardiogr (2017) . DOI: 10.1016/j.echo.2017.01.007 PubMed: 28314623