Aortic Regurgitation Flashcards
What is the underlying pathology of aortic regurgitation?
Inadequate closure of the aortic valve leaflets, leading to regurgitation and increased left ventricular diastolic pressure and volume.
What type of left ventricular hypertrophy occurs in aortic regurgitation?
Eccentric hypertrophy due to increased preload and the need to maintain cardiac output via Starling forces.
What is the long-term consequence of untreated aortic regurgitation?
Progressive left ventricular dilation, systolic dysfunction, and eventual heart failure.
What are the main causes of acute aortic regurgitation?
Infective endocarditis and aortic dissection.
Which heart valve is most commonly affected by infective endocarditis?
The mitral valve, followed by the aortic valve, with the tricuspid valve third.
What are the high-risk factors for aortic dissection?
- Hypertension
- Bicuspid aortic valve (Turner syndrome)
- Marfan syndrome
- Ehlers-Danlos syndrome
- Syphilitic aortitis
- Prior cardiac surgery
What is the classic presentation of an aortic dissection?
Severe, tearing chest pain radiating to the back, pulse or blood pressure deficits between right and left arm, and a widened mediastinum on chest X-ray.
What are the major causes of chronic aortic regurgitation?
- Bicuspid aortic valve
- Rheumatic heart disease
- Marfan syndrome
- syphilitic aortitis
- other connective tissue disorders
What is the most common cause of aortic regurgitation in immigrants from developing countries?
Rheumatic heart disease.
What are the common symptoms of aortic regurgitation?
Exertional dyspnea, orthopnea, paroxysmal nocturnal dyspnea, and palpitations due to increased stroke volume.
How does acute aortic regurgitation differ from chronic in presentation?
Acute presents with severe heart failure and cardiogenic shock, while chronic progresses gradually with compensatory dilation.
What type of murmur is heard in aortic regurgitation?
A early diastolic decrescendo murmur, best heard at the left lower sternal border.
How does increased afterload alter the murmur associated with aortic regurgitation?
Increases in intensity.
What is an Austin Flint murmur?
A low-pitched, mid-diastolic murmur caused by regurgitant flow impinging on the anterior mitral leaflet, mimicking mitral stenosis.
Where is the murmur of aortic regurgitation best heard?
At Erb’s point (left third intercostal space) with the diaphragm while the patient is leaning forward and exhaling.
What is a water hammer pulse?
A rapid rise and fall of the pulse due to increased stroke volume and rapid diastolic runoff.
What is a wide pulse pressure in aortic regurgitation?
A high systolic and low diastolic pressure due to increased stroke volume and rapid diastolic runoff.
What is de Musset’s sign?
Head bobbing with each heartbeat, seen in severe aortic regurgitation. The uvula can also pulsate.
What is the best initial test for diagnosing aortic regurgitation?
Transthoracic echocardiogram (TTE).
What imaging modality is used for further evaluation of the aortic root?
Cardiac MRI or CT angiography.
What is the treatment for acute aortic regurgitation?
Emergent aortic valve replacement (AVR) due to hemodynamic instability.
What medications are used for chronic aortic regurgitation?
Afterload-reducing agents (ACE inhibitors, nifedipine) to reduce regurgitant volume.
What are the indications for aortic valve replacement in chronic aortic regurgitation?
Symptomatic patients, left ventricular ejection fraction <55%, or significant left ventricular dilation.
