Images in cardiovascular medicine
The apical five-chamber view is the echocardiographic view most commonly used for the assessment of transvalvular aortic gradient, because it is the easiest to obtain1 and it allows an optimal imaging plane alignment for the assessment of aortic valve disease.2,3 Thus, it should guarantee an estimate of the maximum possible gradient across the valve. Many authors have stressed the importance of a really comprehensive echocardiographic assessment of patients with known or suspected aortic stenosis, with particular emphasis on the application of the less utilized right parasternal view (RPV).1,3,4 This view is obtained by positioning the probe from second to fifth intercostal space on the right side of the sternum, with the pointer oriented toward the left side of the patient.2,3 However, the difficulty of obtaining the RPV in middle-aged and elderly people is responsible for the common underemployment of this view in routine practice.
In an attempt to better evaluate patients in regular follow-up for aortic stenosis at our echocardiographic laboratory, we applied the RPV to some difficult cases in which the gradient from the five-chamber view seemed underestimated in respect to the indexed aortic valve area (AVA) measured from the zoomed visualization of the aortic valve in the parasternal short-axis view at the level of the great vessels.
As reported in the literature, transvalvular aortic velocity and gradient obtained from the RPV were similar to those from the five-chamber view.1 In one patient, though, the peak and mean gradients measured from the five-chamber view were underestimated for the corresponding indexed AVA (measuring 0.6 cm2/m2, Figs 1 and 2), and the grading of the stenosis was difficult when relying on these contrasting data. From the RPV, though, we obtained a notably higher gradient (Fig. 3), consistent with the indexed area calculated for the aortic valve. Thus, with these new and more comprehensive data, the stenosis was graded as severe.
In the RPV, the probe lies nearer to the aortic valve, aortic root and ascending aorta, and the higher gradient found can be explained by the almost perfect parallelism of the ultrasound beam with respect to these structures. Even though the two-dimensional visualization of cardiac structures from this view is not fair enough to permit an accurate assessment of valve morphology, the estimate of transvalvular aortic gradient is possible and valuable, especially when a final decision for the best management of patients must be taken relying on the measured gradients.
1. Williams GA, Labovitz AJ, Nelson JG, Kennedy HL. Value of multiple echocardiographic views in the evaluation of aortic stenosis
in adults by continuous-wave Doppler. Am J Cardiol
2. Luckie M, Buckley H, Khattar R. Echocardiographic detection of atrial septal defects: the forgotten view. Echocardiography
3. Marcella CP, Johnson LE. Right parasternal imaging: an underutilized echocardiographic technique. J Am Soc Echocardiogr
4. de Monchy CC, Lepage L, Boutron I, et al. Usefulness of the right parasternal view
and nonimaging continuous-wave Doppler transducer for the evaluation of the severity of aortic stenosis
in the modern area. Eur J Echocardiogr