Percutaneous Treatment of Left Side Cardiac Valves by Corrado Tamburino Marco Barbanti & Davide Capodanno

Author:Corrado Tamburino, Marco Barbanti & Davide Capodanno
Language: eng
Format: epub
Publisher: Springer International Publishing, Cham

Calibration of the gains and filters allows an accurate delineation of anatomical details of the valve, while the addition of colored tissue maps increases the perception of depth in 3D. The transesophageal approach with scans from the mid-upper portion of the esophagus affords a better spatial resolution and, therefore, a better image quality for a 3D evaluation of the aortic valve.

The addition of color Doppler imaging can help to overcome the inaccuracy of spectral Doppler ultrasound for SV calculation. By providing a direct measure of the actual flow, color 3DE does not need nonsimultaneous measurements of the time-velocity integral and cross-sectional area of the LV outflow tract, thereby reducing the potential for errors. The measurement of stroke volume with color 3DE has proven to be more accurate than the two-dimensional continuity equation, even in situations with altered geometry of the outflow tract, such as in basal septum hypertrophy in the elderly.

Another method for the 3D calculation of LV stroke volume is that derived from 3D volume calculation, by subtracting the end-systolic volume from end-diastolic volume and adding the result to the numerator of the usual CE.

3DE allows better identification of the minimum orifice, especially in the case of commissural fusion or a valve with dome-shaped appearance. The planimetric area, measured by transesophageal 3D (3D TEE), has been shown to have a high correlation with the AVA derived from the continuity equation or calculated with Gorlin formula at catheterization. Furthermore, direct planimetry at 3D TEE has shown a higher accuracy compared with 2D TEE, which significantly overestimates the AVA. The superior ability of 3D TEE to better outline aortic valve morphology and measure the contours of cusps and commissures is the real advantage to 3D TEE over 2D TEE imaging. Nevertheless, the presence of calcification may make it difficult to trace the planimetry of the orifice area, due to masking phenomena and glare caused by calcification. In addition, as for 2DE, planimetry can overestimate the severity of aortic stenosis in patients with low stroke volume, due to reduced opening of the valve’s anatomic area.

An exercise test is contraindicated in symptomatic patients with AS owing to a high risk of complications, including syncope, ventricular tachycardia, and death. In asymptomatic patients, it can be performed under close monitoring and has great prognostic value [21, 22]. Reduced tolerance to effort, onset of symptoms, and abnormal blood pressure response, such as an increase of less than 20 mmHg or a fall below baseline, are associated with an unfavorable outcome, so these patients should be considered symptomatic. In these cases, aortic valve replacement seems to be associated with a better outcome compared with medical treatment. ST segment depression is commonly seen and is nonspecific for CAD. Exercise stress echocardiography is challenging and seldom necessary. However, it may provide prognostic information in asymptomatic severe AS by assessing the increase in mean pressure gradient and the systolic pulmonary arterial pressure and change in LV function [23–25].

Multislice computed tomography (MSCT) and Cardiac magnetic resonance (CMR) imaging are increasingly used

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