CHAPTER 10: Aortic Regurgitation

ETIOLOGIES OF VALVULAR REGURGITATION

• Infection.

• Calcification.

• Fibrosis.

• Degeneration (aging).

• Annular dilatation.

• Physiology (structurally normal valve).

• Note: Prolapse, vegetations, and calcifications may not cause significant regurgitation.

• Pitfall: Color Doppler display of valvular regurgitation is affected by the following instrument settings:

  • - Transducer frequency.

  • - Gain settings.

  • - Nyquist settings.

  • - Image sector size.

  • - Image sector depth.

• Momentum of blood flow affects color flow jet area.

  • - Flow rate × flow velocity = momentum.

• Practical example:

  • - The momentum of left ventricular systolic “driving” pressure affects color flow display of mitral regurgitation jet area. The “driving” pressure is equal to the systolic blood pressure (in the absence of aortic stenosis).

  • - This pressure-related variability in regurgitant jet size on color flow is a frequent problem during intraoperative TEE interpretations of mitral regurgitation severity.

MECHANISM OF AORTIC REGURGITATION

• Abnormal anatomy: Trileaflet, bicuspid, unicuspid, quadricuspid.

• Dilatation of the aortic root, normal cusps, inadequate coaptation.

• Cusp prolapse.

• Leaflet retraction (Fig. 10-1).

Sources

• Lansac E, Di Centa I, Raoux F, et al. A lesional classification to standardize surgical management of aortic insufficiency towards valve repair. Eur J Cardiothorac Surg. 2008;33:872–878.

• le Polain de Waroux JB, Pouleur AC, Goffinet C, et al. Functional anatomy of aortic regurgitation: accuracy, prediction of surgical repairability, and outcome implications of transesophageal echocardiography. Circulation. 2007;116:264–269.

EVALUATION OF AORTIC REGURGITATION

• Auscultation hallmark: early diastolic decrescendo murmur.

• The second heart sound may be increased due to hypertensive aortopathy. In some of these patients, the aortic component of the second heart sound can develop a musical quality called a “tambour” A2.

• The second heart sound may be decreased in patients with aortic regurgitation that is being caused by restricted leaflet motion in combined aortic stenosis and aortic regurgitation (AS/AR).

• AS/AR murmurs have a to-and-fro bellows quality with a decreased A2 between the harsh systolic ejection murmur and the blowing decrescendo diastolic regurgitation murmur.

• Chronic severe aortic regurgitation has numerous eponyms for physical findings caused by the wide pulse pressure:

  • - Corrigan pulse: prominent pulsations of the carotid arteries.

  • - Bisferiens pulse: double systolic arterial impulse—the so-called twice-beating heart.

  • - De Musset sign: head nodding with each heartbeat.

  • - Duroziez sign: systolic and diastolic femoral artery bruit.

  • - Hill sign: accentuated leg systolic pressure with >40 mm Hg difference from the brachial artery systolic pressure.

  • - Muller sign: pulsation of the uvula with each heartbeat.

  • - Palmar click: palpable systolic flushing ...