Page 73 - Critical Care Notes

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Pathophysiology
■ Mitral stenosis: Usually results from rheumatic fever (which can cause
valve thickening), atrial myxoma (tumor), calcium accumulation, or throm-
bus formation → valve becomes stiff. The valve opening narrows → pre-
vention of normal blood flow from left atrium to left ventricle → pulmonary
congestion → right-sided heart failure.
■ Mitral valve regurgitation: Fibrotic and calcific changes prevent mitral
valve from closing completely during systole → incomplete closure of
the valve → backflow of blood into left atrium when left ventricle contracts
→ increased volume ejection with next systole → increased pressure → left
ventricular hypertrophy.
■ Mitral valve prolapse: The valvular leaflets enlarge and prolapse into left
atrium during systole → usually benign but may lead to mitral valve regur-
gitation.
■ Aortic stenosis: Aortic valve orifice narrows and obstructs left ventricle
outflow during systole → increased resistance to ejection or afterload
→ ventricular hypertrophy.
■ Aortic regurgitation: Aortic valve leaflets do not close properly → regurgita-
tion of aortic blood back into ventricle during diastole → left ventricular
hypertrophy.
Clinical Presentation
■ Mitral stenosis: Fatigue, dyspnea on exertion, heart palpitations, heavy
coughing, frequent respiratory infections, orthopnea, paroxysmal nocturnal
dyspnea, hemoptysis, hepatomegaly, JVD, pitting edema, atrial fibrillation,
apical diastolic murmur
■ Mitral valve regurgitation: Fatigue, dyspnea on exertion, orthopnea, palpi-
tations, atrial fibrillation, JVD, pitting edema, high-pitched holosystolic
murmur
■ Mitral valve prolapse: Atypical chest pain, dizziness, syncope, palpitations,
atrial tachycardia, ventricular tachycardia, systolic click
■ Aortic stenosis: Dyspnea on exertion, angina, syncope on exertion, fatigue,
orthopnea, paroxysmal nocturnal dyspnea, harsh systolic crescendo-
decrescendo murmur
■ Aortic insufficiency: Palpitations, dyspnea, orthopnea, paroxysmal nocturnal
dyspnea, fatigue, angina, sinus tachycardia, blowing decrescendo diastolic
murmur
Diagnostic Tests
■ Echocardiogram
■ ECG
■ Cardiac angiogram
■ Exercise tolerance test
■ Chest x-ray
CV