Valvular Heart Disease

Part 2: Aortic Valve

Aortic stenosis (AS)

AS-Etiology

• Senile calcification

-CAD risk factors, ? use of statins

• Congenital

- bicuspid most common, presents in adulthood

- true congenital• Rheumatic heart disease

- mitral always involved as well

AS-Pathophysiology

• Pressure overload wall stress LV hypertrophy

• LVH leads to:

1. increased oxygen demand

2. reduced LV compliance, higher diastolic pressure at same volume

3. lower aortic pressure with reduced systemic perfusion and coronary blood flow

AS-Symptoms

AS-Symptoms

• Angina

Increased O2 demand, decreased supply

Mainly exertional

• Syncope

Exertional- vasodilatation with fixed output

• Congestive heart failure Reduced compliance, eventually systolic

dysfunction

AS-Physical diagnosis

AS-Physical diagnosis

• PMI is sustained and laterally displaced

• Fourth heart sound

• Systolic murmur at base radiating to carotids, crescendo-decrescendo

• Time to peak of murmur, reduced second heart sound, pulsus parvus et tardus correlate with AS severity

AS-Diagnosis

AS-Diagnosis

AS-Medical therapy

AS-Surgical intervention

• Any appearance of symptoms

• Asymptomatic pts can be followed-– Consider ETT to evaluate FC

• In general, AVR

AS-surgical intervention

Almost 100% restenosis at 6 mos.

Percutaneous valve replacement

• Symptomatic AS

• Not candidates/high-risk for surgery

AR-Etiology

Diseases of the valve

1. Rheumatic heart disease

2. Calcific/degenerative

3. Rheumatoid arthritis, ankylosing spondylitis, SLE

4. Congenital-bicuspid, VSD, DSS

AR-Etiology

Diseases of the aorta

1.Marfan’s, other connective tissue disorders

2. Hypertension

3. Tertiary syphillis

4. Aortic aneurysm\dissection (acute)

AR-Pathophysiology

Extreme volume overload LV dilatation

As in MR, LV function initially preserved but gradually decreases

Unlike MR, no reduced afterload and only compensation is dilatation

AR-Pathophysiology

Increased LV mass increases O2 demand

Reduced aortic diastolic pressure leads to decreased coronary perfusion and reduced O2 supply

AR-Symptoms

• Long latent, asymptomatic period

• Symptoms generally appear after significant LV dilatation has already occurred.

• Congestive heart failure

• Rarely, angina due to decreased coronary perfusion

AR-Physical diagnosis

• Peripheral wide pulse pressure

“waterhammer” or “pistol-shot” pulses head-bobbing, “dancing” uvula

• CardiacPMI laterally and downwardly displacedDecrescendo diastolic murmur (sitting up) -duration correlated with severityApical diastolic murmur (“Austin-Flint”)

AR-Medical therapy

• Afterload reduction- ACEI, hydralazine, nifedipine

Unlike MR, randomized trials available

• Acute-immediately to OR

AR-Surgical intervention