University:
Northwest College
Course:
VN 220 | Medical/ Surgical
Academic year:

2024
Views:

437

Pages:

3
Author:

Yesenia M.

Mitral Stenosis Results in reduced blood flow from the atrium into the ventricle. Usually caused by rheumatic endocarditis. Rheumatic endocarditis progressively thickens mitral valve leaflets and chordae tendinae, causing the leaflets to fuse together. Eventually, the mitral valve orifice narrows and obstructs blood flow into the ventricle. Pathophysiology: Normally, the mitral valve orifice is a wide as the diameter of 3 fingers. In severe mitral stenosis, the orifice narrows to the width of a pencil. Due to resistance through the narrowed valve orifice, the atrium is less able to push blood into the ventricle. This results in a residual blood volume in the atrium, which over time causes atrial hypertrophy and dilation. Blood flow into the ventricle leads to ventricular filling and decreased cardiac output. Results in congestion of the pulmonary circulation. Right ventricle: Must then contract against abnormally high pulmonary arterial pressure and is subjected to excessive strain. Right ventricle: Hypertrophy, enlarges and fails. Signs and Symptoms: Dyspnea on exertion (DOE) Progressive fatigue Decreased exercise tolerance (↓ VO) Dry cough/wheezing (↑ pressure on the bronchial tree) Blood expectoration (in severe cases) Palpitations Orthopnea Paroxysmal nocturnal dyspnea Repeated RR infections Dilation and hypertrophy of the right atrium Atrial arrhythmias Assessment and Diagnostic Findings: Low-pitched, rumbling diastolic murmur heard at the apex. Weak, irregular pulse. Echo: Used to diagnose and quantify severity of mitral stenosis. EKG, exercise test, cardiac catheterization (angiography): Help determine severity. Medical management: Anticoagulant meds: To ↓ risk of developing atrial thrombosis. Cardioversion: To treat atrial fibrillation if it develops. Beta-blockers, digoxin, calcium channel blockers. Avoid strenuous activity, competitive sports, and pregnancy (because these ↑ HR). SX: Valvuloplasty, commissurotomy.