Hemodynamic Findings of Severe Subacute Aortic Regurgitation

J INVASIVE CARDIOL 2017;29(6):E74.

Key words: hemodynamics, acute aortic regurgitation

A 42-year-old woman with a history of cocaine abuse presented with a 1-month history of worsening exertional dyspnea and intermittent chest pain at rest. Transthoracic echocardiography revealed mildly reduced left ventricular systolic function, severe aortic regurgitation, and eccentric moderate-to-severe mitral regurgitation. Left heart catheterization demonstrated severe subacute aortic regurgitation with equalization of the left ventricular end-diastolic pressure and the aortic diastolic pressure, a mildly increased pulse pressure, and systemic hypotension. She was referred for surgical repair. During surgical exploration, she was found to have a structurally intact trileaflet aortic valve and a circumferential piece of tissue above the sinuses of Valsalva consistent with a chronic type A aortic dissection. Her dissection was successfully repaired without any complications.

This case demonstrates the classic hemodynamic findings of acute aortic regurgitation, which differ from those of chronic aortic regurgitation. During diastole, acute aortic regurgitation leads to a rapid decline in aortic pressure. In a normal left ventricle without compensatory remodeling, the large regurgitant volume leads to a rapid increase in the left ventricular filling pressure.¹ As seen in Figure 1, during diastole, the left ventricular end-diastolic pressure approaches or equals the aortic diastolic pressure. There is a small transvalvular systolic gradient (because of the increased flow across the aortic valve), which increases after an ectopic beat because of a prolonged diastolic filling period. Also seen in Figure 1, the decreased effective cardiac output typically leads to systemic hypotension.² Finally, in contrast to chronic aortic regurgitation, the pulse pressure in acute aortic regurgitation is typically normal or mildly increased.^1-3

References

1.    Stouffer GA, Uretsky BF. Hemodynamic changes of aortic regurgitation. Am J Med Sci. 1997;314:411-414.

2.    Bekeredjian R, Grayburn PA. Valvular heart disease: aortic regurgitation. Circulation. 2005;112:125-134.

3.    Kern MJ, Aguirre FV. Interpretation of cardiac pathophysiology from pressure waveform analysis: aortic regurgitation. Cathet Cardiovasc Diagn. 1992;26:232-240.

From the University of North Carolina Hospitals, Division of Cardiology, Chapel Hill, North Carolina.

Disclosure: The authors have completed and returned the ICMJE Form for Disclosure of Potential Conflicts of Interest. The authors report no conflicts of interest regarding the content herein.

Manuscript accepted November 29, 2016.

Address for correspondence: George A. Stouffer, MD, University of North Carolina Hospitals, 160 Dental Circle, CB #7075, Chapel Hill, NC 27599-7075. Email: Rick_Stouffer@med.unc.edu