Cardiac Auscultation

Cardiac Auscultation and Valvular Disease

• Cardiac auscultation helps identify:
  • Valvular heart disease
  • Heart failure
  • Dysrhythmias
  • Presence of clinically significant vs. insignificant murmurs
• Goals of cardiac evaluation:
  • Identify severity of cardiac disease
  • Identify degree of impaired myocardial contractility
  • Identify other organ involvement (kidneys, liver, brain, pancreas)

Mitral Stenosis

• Most common cause: rheumatic fever
• Females > Males
• Pathology:
  • Diffuse thickening of leaflets
  • Calcification of annulus
• Slow process (20-30 years) leading to:
  • CHF
  • Pulmonary hypertension
  • RV failure
• Symptoms:
  • DOE
  • Orthopnea
  • PND
  • AF (dilated LA)
• Diastolic murmur
• Normal orifice: 4-6 cm2
• Symptoms develop at about 1.5 cm2
• Severe/critical disease: 0.6-1.0 cm2
• Transvalvular gradient of 10 mmHg
• Early- to mid-diastolic murmur at the apex
• Opening snap, low-pitched rumble radiating to axilla
• Findings warrant further workup:
  • Gold standard: echo
  • Looking for valve area, LV function, transvalvular pressure gradient, pulmonary hypertension
  • Evaluated with EKG as well
  • POCUS: classic sign is "doming" of anterior valve leaflet

Mitral Regurgitation

• Associated with MS if rheumatic in origin
• If isolated MR, assume ischemic disease until proven otherwise
• Can be ruptured chordae tendineae
• Decreased forward LV stroke volume and CO
• Portion of every stroke volume regurgitated through incompetent mitral valve back into LA
• Insidious progression, symptoms often not elicited or are nonspecific
• Long-term enlargement of LV to compensate
• Compensation of increase LA compliance/LVH accommodate increased volume
• If acute rupture: pulmonary edema/cardiogenic shock
• Holosystolic murmur at apex
• High-pitched, blowing, loud S3 radiating to axilla
• Cardiomegaly on physical exam or CXR
• EKG changes: LA/LV enlargement
• Gold standard: echo
  • LA size
  • Pressure
  • LV wall thickness
  • LV function
• Cardiac cath if severity cannot be confirmed

Mitral Valve Prolapse

• Leaflets prolapse back into LA with or without MR (during systole)
• Most common lesion: 1-2.5% of population
• Associated with:
  • Marfan's Syndrome
  • Rheumatic carditis
  • Myocarditis
  • Lupus
• Usually benign but can lead to:
  • CVA (embolic)
  • Dysrhythmias
• Mid- to late-systolic click and late-systolic murmur (crescendo)
• Symptoms:
  • Anxiety
  • Orthostatic hypotension
  • Palpitations
  • Dyspnea
  • Fatigue
  • Atypical chest pain
• Echo to determine degree of prolapse and associated LV involvement

Aortic Stenosis

• Most common valvular lesion in the US
• Degeneration and calcification of leaflets (aging)
• Bicuspid v. tricuspid valve (congenital, younger)
• Associated with risk factors similar to ischemic heart disease
• Symptoms:
  • Angina (without CAD)
  • Syncope
  • CHF
• 75% of patients with symptoms die within 3 years without replacement
• Mid-systolic murmur in 2nd right and left parasternal spaces
• Crescendo-decrescendo diamond pattern, radiates to carotid(s), S3 and S4 if significant
• Contour of diamond relates to severity of pressure gradient across valve
• MANY PATIENTS ARE ASYMPTOMATIC, so ALL old people are at risk until ruled out
• EKG may show LVH
• Echo to determine:
  • Valve morphology
  • LV function
  • Aortic valve area & pressure gradient measurements
• Cardiac cath may be necessary if echo is not diagnostic
• Symptoms when pressure 25-40 mmHg & valve area### Cardiac Auscultation
• Cardiac auscultation helps identify valvular heart disease, heart failure, dysrhythmias, and the presence of clinically significant murmurs.
• The technique starts with an interview and involves auscultating the heart and lungs for all patients.

Heart Valves and Murmurs

• Heart murmurs are graded on a scale of I to VI, with VI being the loudest and requiring no stethoscope.
• Mitral stenosis is the most common cause of heart murmurs, often resulting from rheumatic fever, and more common in females than males.

Mitral Stenosis

• Mitral stenosis is characterized by diffuse thickening of leaflets and calcification of the annulus, leading to a slow process (20-30 years) that eventually develops into congestive heart failure (CHF) and pulmonary hypertension.
• Symptoms of mitral stenosis include dyspnea, orthopnea, and paroxysmal nocturnal dyspnea (PND) and are often precipitated by pregnancy or illness.
• The normal mitral orifice is 4-6 cm², and symptoms develop when the orifice area is reduced to around 1.5 cm², with severe disease occurring at an orifice area of 0.6-1.0 cm².
• A transvalvular gradient of 10 mmHg is indicative of severe disease.

Mitral Regurgitation

• Mitral regurgitation is often associated with mitral stenosis if rheumatic in origin, but if isolated, it is assumed to be ischemic disease until proven otherwise.
• Ruptured chordae tendineae can also cause mitral regurgitation.
• Decreased forward left ventricular (LV) stroke volume and cardiac output are characteristic of mitral regurgitation, with a portion of every stroke volume regurgitating through the incompetent mitral valve back into the left atrium (LA).
• Long-term LV enlargement can compensate for the increased volume.

Mitral Valve Prolapse

• Mitral valve prolapse is characterized by leaflets prolapsing back into the LA with or without mitral regurgitation during systole.
• It is the most common lesion, affecting 1-2.5% of the population, and is associated with Marfan's syndrome, rheumatic carditis, myocarditis, and lupus.
• The condition is usually benign but can lead to cerebrovascular accidents (CVAs) and dysrhythmias.

Aortic Stenosis

• Aortic stenosis is the most common valvular lesion in the US, resulting from degeneration and calcification of leaflets, often due to aging or congenital bicuspid valve.
• Associated risk factors include those similar to ischemic heart disease.
• Symptoms of aortic stenosis include angina, syncope, and CHF, with 75% of patients dying within 3 years without valve replacement.
• The condition often goes undiagnosed until symptoms appear, putting all older adults at risk until ruled out.