The Use of Contrast May Improve Aortic Valve Assessment During Transesophageal Echocardiography.

OBJECTIVES: The Doppler profile that quantifies the degree of aortic stenosis is essential, as an inaccurate measurement can alter the surgical plan. The authors aimed to examine the level of agreement between the contrast and noncontrast methods of aortic valve sizing during intraoperative transesophageal echocardiography (TEE).

SETTING: At a tertiary hospital.

PARTICIPANTS: A total of 30 patients undergoing surgical aortic valve replacement for a stenotic valve.

INTERVENTIONS: Perflutren lipid microsphere contrast injection.

MEASUREMENTS AND MAIN RESULTS: The authors reviewed Doppler studies of 30 consecutive patients undergoing aortic valve replacement in whom a contrast agent was given (perflutren lipid microsphere). They measured the peak and/or mean aortic valve gradients and velocity time integral readings through the left ventricular outflow tract (LVOT), and the aortic valve before and after administering the contrast agent. The aortic valve area was then calculated using both methods. Paired t tests and Bland-Altman analyses were used to examine the bias and the level of agreement between the 2 processes. By not using a contrast agent, the aortic valve area was overestimated by 0.26 cm2 compared to those measured by transthoracic echocardiography (TTE) (p < 0.001). Using a contrast agent, TEE measurements were comparable to those obtained by TTE. Moreover, the peak and mean aortic valve gradients were underestimated by 19 and 11 mmHg, respectively (p value <0.001). Adding contrast did not affect the pulse-wave Doppler readings of the V1 velocity of the LVOT.

CONCLUSION: This discrepancy is significant and could affect the decision to replace the aortic valve. When evaluating the aortic valve with TEE, the authors recommend using a contrast agent to improve the Doppler profile and to obtain a more accurate measurement of the aortic valve area.