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There are four heart valves each of which can have essentially two problems.

Heart valves

• Aortic valve
  • Blood flows from LV into Aorta
• Pulmonary valve
  • Blood flow from RV into pulmonary arteries
• Mitral valve
  • Blood flows from left atrium into the LV
• Tricuspid valve
  • Blood flow from right atrium into the RV

Heart sounds

• Aortic valve heart sounds
  • May be heard on the left or the right sternal border
  • 2-4 intercostal space
• Pulmonary valve
  • Left sternal border
  • 2 intercostal space
• Mitral Valve
  • Left midclavicular line
  • 5^th intercostal space
• Tricuspid
  • Left sternal border
  • 4^th intercostal space

The only two real problems each of them can have is stenosis or regurgitation.  They are either stiff and don’t open well or they allow backflow.

Aortic Valve

The aortic valve lies between the the left ventricle of the heart and the aorta.  Therefore it is a high pressure system carrying oxygenated blood out to the body.

Aortic Stenosis

Aortic stenosis is believed to be similar to atherosclerosis.  The most common valvular heart disease in the U.S.

Causes

• A congenital bicuspid or unicuspid valve. Symptoms of this usually occur in middle age.
• Rheumatic fever
• Degenerative or calcific aortic stenosis. Upwards of 25% of patients over 65 have some degree of aortic stenosis.

Clinical Presentation

• Routine medical exam
• Exertional dyspnea
• Syncope
• Angina – secondary to poor perfusion of coronary arteries
• CHF

Physical Exam Findings

• Murmur
  • RIGHT 2^nd interspace
  • Harsh crescendo-decrescendo mid systolic ejection murmur
  • Very commonly radiates to the right neck
  • Hear best with patient sitting and leaning forward.

Labs & Studies

• ECG – left ventricular hypertrophy
• Chest x-ray – Calcified aortic valve
• Echo with Doppler is diagnostic

Treatment

• Medication
  • Angina
    • Beta blockers
    • Calcium Channel Blockers
    • Avoid Nitrates due to risk of severe hypotension
• Aortic Valve replacement
  • Prosthetic – last longer but require anticoagulation
  • Pericardial and porcine valves do not require anticoagulation but have a shorter lifespan
  • Ross procedure – replacement of aortic valve with patient’s own pulmonary valve and a cadaver valve replaces the pulmonary valve.
  • Balloon valvuloplasty not effective long term
• Generally recommended to avoid arterial vasodilators in patients with severe left ventricular outflow obstruction
  • ACEI
  • Beta Blockers
  • Nitroglycerin

Aortic Insufficiency (Regurgitation)

• The leaky valve allows the back flow of blood during diastole.
• Males more commonly 3:1

Causes

• Aortic root dilation
  • 80% idiopathic
  • Aging
  • HTN
  • etc
• Rheumatic fever is historically relevant, but is now less common due to widespread antibiotic use.
• Congenital bicuspid aortic valve
• Diseases
  • Marfan syndrome
  • Ehlers-Danlos syndrome
  • Ankylosing spondylitis
  • Systemic Lupus
  • Syphilis
• Acute setting
  • Endocarditis
  • Aortic dissection

Clinical Presentation

• Routine medical exam – asymptomatic until middle aged
• Exertional dyspnea
• Orthopnea
• Angina
• Paroxysmal nocturnal dyspnea
• Palpitations

Physical Exam Findings

• Murmur
  • 2^nd to 4^th LEFT interspace
  • Early diastolic decrescendo
  • Heard best with patient sitting and leaning forward
  • Isometric exercise will increase systemic vascular resistance and increase the murmur
• High arterial pulse pressures with a quick drop in pressure during diastole

Labs & Studies 

• Chest x-ray – left ventricular hypertrophy
• ECG – left ventricular hypertrophy
• Echo with Doppler is diagnostic
• Cardiac cath may also be used

Treatment

• Blood pressure control focusing on decreasing after load
• Valve replacement