19 - Valvular Heart Disease

Valve stenosis and regurgitation Thai names

ลิ้นหัวใจตีบ vs ลิ้นหัวใจรั่ว

Stenosis causes _ overload of the upstream chamber while regurgitation causes _ overload of the upstream chamber

Stenosis → pressure overload

Regurgitation → volume overload

2 most common valvular heart diseases

1. Aortic stenosis

2. Mitral regurgitation

Aortic stenosis most common cause

Degeneration from calcification

Rheumatic heart disease can cause what diseases?

All of the main 4: Aortic stenosis, regurgitation, mitral stenosis, regurgitation

• It is also the main cause of mitral stenosis

What are the 2 main kinds of degenerative valve disease, and how do they work?

1. Calcification: Typically, calcium deposits at the cusps of the aortic valve, or at the annulus of the mitral valve

2. Myxomatous: A soft, floppy and large valve due to an increase in proteoglycan while collagen/elastic fibers break down, usually affecting the mitral valve

Which one of calcific aortic stenosis and myxomatous mitral valve is asymptomatic?

Myxomatous mitral valve

What condition is associated with myxomatous mitral valve, and what is something we can see in gross?

Marfan syndrome

In myxomatous mitral valve, we can see hooding of the mitral leaflets

Non-bacterial thrombotic endocarditis

Vegetations along the closure lines of valve leaflets that aren’t from bacteria, often in patients with hypercoagulable states like advanced cancers, hyperestrogenic patients or chronic DIC

Libman-Sacks endocarditis

Endocarditis found in SLE that can form vegetations on valve leaflets on either side

What flow causes murmurs, and what factors affect that?

1. Turbulent flow, boosted by density, velocity, diameter, and decreased by viscosity

Aortic stenosis

• Driving cause

• LV pressure

• Wall stress

• LVEDP

• Stroke volume

• Increased LV afterload from stenosis

  • LV pressure: Increased

  • Wall stress: Increased

  • LVEDP: Increased

  • Stroke volume: Decreased

Aortic stenosis

• Compensation

• Concentric hypertrophy, LA hypertrophy

Aortic stenosis classic symptoms and their reasons

Usually asymptomatic for a really long time

1. Angina: Because hypertrophied muscle demands more O2, decreased stroke volume due to stenosis can’t meet that

2. Exertional syncope: Vasodilation by exercise causes MAP = CO x TPR equation to decrease bc TPR decreases

3. Heart failure: Because less blood is ejected

What condition is bad to have with AS, and why?

Atrial fibrillation because the quivering atria can’t “kick” to provide the boost of blood into the LV

Aortic regurgitation

• Driving cause

• LV volume

• LVEDP

• Stroke volume

• Diastolic back flow from aorta

• LV volume: Increased

• LVEDP: Increased

• Stroke volume: Increased

Acute vs chronic aortic regurgitation

• Acute: Sudden destruction of valve → LV can’t handle all of the fluid → LVEDP goes up, fluid goes back into lungs and causes pulmonary edema while forward output fails

• Chronic: Occurs over years, ventricle remodels via eccentric hypertrophy to boost compliance

Chronic aortic regurgitation symptoms

• Usually asymptomatic, but when symptoms show:

  • Dyspnea on exertion

  • Fatigue

  • Decreased exercise tolerance

  • Paroxysmal nocturnal dyspnea

  • Orthopnea

  • Widened pulse pressure

Pulsus parvus et tardus is associated with?

Aortic stenosis

Patients who have aortic stenosis are split into what groups?

1. Under 70: Usually a unicuspid/bicuspid congenital valve issue

2. Over 70: Senile degeneration

Aortic regurgitation main causes

1. Primary valve disease: Rheumatic heart disease, infective endocarditis, congenital bicuspid

2. Root(aortic root, contains the annulus) disease: Congenital like Marfan/Ehler Danlos, acquired dilated aorta like takayasu arteritis or degenerative causes(hypertension, atherosclerosis)

What chambers dilate in AR?

LV, then LA if the left ventricle fails or causes secondary MR

Corrigan’s pulse

• What is it

• Found in?

• Forceful distention of carotid arteries

• Chronic AR

Mitral stenosis main cause

Many years after acute rheumatic carditis

What are serious mitral stenosis consequences?

1. Atrial fibrillation due to abnormal conduction of dilated LA

2. Thrombi due to the atrail fibrillation

Mitral stenosis symptoms

1. Dyspnea on exertion

2. Reduced exercise capacity

3. Fatigue

4. Pulmonary congestion

5. Hoarseness

6. Hemoptysis

Why does hemoptysis happen in MS?

Pulmonary hypertension → increased flow to bronchial circulation → rupture

When does the leak happen in MR?

Systole

EF in mitral regurgitation

Increased because of contractility boosted but also because the blood is leaving back to the LA

Is chronic or acute MR more dangerous, and why?

Acute MR is more dangerous because the LA hasn’t had time to dilate and adapt to become more compliant, so it pushes back into the lungs → Pulmonary edema

Acute MR cause

• Papillary muscle rupture after MI

MR causes

1. Primary: Myxomatous degeneration, rheumatic disease, IE, papillary/chordal muscle rupture

2. Myocardial issue(Like remodeling after MI)

MR murmur

• Duration

• Pitch

• Holosystolic(pansystolic)

• High

What symptoms are found in all of MS, MR, AS, AR?

Symptoms of a failing left heart:

• Forward symptoms: Fatigue, weakness, reduced exercise tolerance

• Backward symptoms: Dyspnea on exertion, orthopnea, PND, pulmonary edema

Which of stenosis or regurgitation is always chronic?

Stenosis

Key symptom of acute regurgitation

Pulmonary edema