NCLEX Focus - Heart Murmurs

The following are high yield points from the Heart Murmurs tutorial to help you prepare for the NCLEX. Review this Heart Murmurs flashcard for further details. Here's an NCLEX-focused summary of the Heart Murmurs tutorial, emphasizing high-yield facts directly derived from the provided material. This version highlights critical knowledge areas for test readiness and clinical reasoning.

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Heart murmurs = abnormal sounds from turbulent blood flow across defective valves. Though echocardiography confirms diagnosis, auscultation remains an essential bedside skill. Causes of murmurs include:

• Valvular calcification
• Infective endocarditis
• Rheumatic fever (post-streptococcal autoimmune)
• Congenital valve defects

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Left atrial pressure: ~10 mmHg Left ventricular pressure: 120 mmHg systolic / 10 mmHg diastolic Aortic pressure: 120/80 mmHg Murmurs result from abnormal pressure gradients and flow disruptions during the cardiac cycle.

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Murmur timing: Systole (holosystolic murmur from S1 to S2) Phonocardiogram: High-pitched, steady sound Hemodynamics:

• Blood leaks from LV to LA during systole
• ↑ LA pressure (high v-wave) → pulmonary congestion/edema
• ↑ LV preload due to increased return → LV dilation
• ↓ Aortic pressure (less forward stroke volume)

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Murmur timing: Diastole (after S2) Phonocardiogram: High-pitched, early diastolic murmur Hemodynamics:

• Blood leaks from aorta to LV during diastole
• ↑ LV preload → ↑ systolic pressure, ↓ diastolic pressure
• ↑ pulse pressure (wide gap between systolic/diastolic)
• ↑ LA pressure, risk of pulmonary congestion

Clinical sign: Corrigan’s sign (dancing carotids / head bobbing)

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Murmur timing: Diastole (after S2, with opening snap) Phonocardiogram: Low-pitched murmur following an opening snap Hemodynamics:

• Narrowed valve → ↑ LA pressure
• Atrial hypertrophy to push blood through stiff valve
• ↓ LV filling, ↓ preload, ↓ stroke volume
• ↓ Aortic pressure, ↓ cardiac output

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Murmur timing: Systole Phonocardiogram: Loud, harsh crescendo-decrescendo murmur Hemodynamics:

• Stiff valve → ↓ aortic pressure during systole
• ↑ LV pressure to overcome stenosis → LV hypertrophy
• ↑ LA pressure → LA hypertrophy

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Atrial hypertrophy from chronic pressure load → risk of atrial fibrillation Heart failure and pulmonary edema can result from elevated left-sided pressures Patent ductus arteriosus causes a continuous murmur, loudest at S2

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Murmur: Mid-systolic click + high-pitched systolic murmur Common in: Marfan syndrome, Ehlers-Danlos, young females Murmur increases with Valsalva (REDUCED preload accentuates leaflet prolapse) Etiology: Myxomatous degeneration of mitral valve leaflets Complications: Severe MVP can lead to mitral regurgitation, sudden cardiac death in athletes Often asymptomatic, but requires monitoring A patient with known Marfan syndrome is being monitored for aortic valve dysfunction. What clinical change would suggest development of aortic insufficiency? A nurse is auscultating a patient’s heart and hears a high-pitched, holosystolic murmur that lasts from S1 to S2, best heard at the apex. What condition is most likely causing this sound? Which of the following hemodynamic changes is expected in a patient with aortic regurgitation? A 15-year-old athlete presents with a mid-systolic click and high-pitched murmur that increases during the Valsalva maneuver. What is the most likely diagnosis?