Mitral Regurgitation: Pathogenesis and clinical findings Coronary Artery Disease
Authors: Juliette Hall, Victoria Nkunu
Reviewers: Raafi Ali, Jack Fu, Usama Malik, Sina Marzoughi, Jason Waechter* * MD at time of publication
(Ischemic Heart Disease & Myocardial Infarction)
Myocarditis
Left ventricular dilation displaces papillary muscles
Dilation of the Tethering of mitral valve annulus chordae tendineae
↑ Volume and pressure in left atrium
↑ Volume pushed back into left ventricle
Dilated left ventricle
Apical impulse on palpation and auscultation
↓ Forward flow of blood out of heart
Blood backs up into pulmonary circulation
↑ Intravascular hydrostatic pressure in pulmonary vessels
Fluid extravasates out of vessels and into the lungs
Papillary muscle rupture
Mitral valve leaflets flail
Mitral valve prolapse
Structurally abnormal valve
Connective tissue disorders
Weak valve leaflets
Rheumatic heart disease
Dilatation of the mitral valve annulus, inflammation of leaflets
Infective endocarditis
Vegetations form on valve leaflets
Mitral Regurgitation
Blood consistently flows backward throughout systole
Holosystolic murmur, radiates to axilla, ↑ with afterload (e.g. making a fist)
Backflow of blood from left ventricle to left atrium due to impaired mitral valve closure
S3 heart sound
Myocardial remodeling
↓ Muscle efficiency
↓ Left ventricle systolic function
↓ O2 saturation, tachypnea, wheeze, ↑ work of breathing, crackles, frothy sputum (if severe)
Congestive heart failure
↓ Stroke volume ejected into aorta
↓ Cardiac output
↓ Organ perfusion ↓ O2 to kidney
Activation of renin-angiotensin- aldosterone system
↑ Reabsorption of water by kidneys
↑ Intravascular hydrostatic pressure systemically
Peripheral edema
Injury to kidney parenchyma
↓ ability for kidney to clear creatinine
↑ Serum creatinine
Legend:
Pathophysiology
Mechanism
Sign/Symptom/Lab Finding
Complications
Published Feb 3, 2018, updated Oct 15, 2023 on www.thecalgaryguide.com