Echocardiography
Echocardiographic examinations were performed by one experienced
physician. The diameter of the cardiac chambers was expressed as the
maximum value of the anteroposterior diameter in cardiac cycles. The
diameter of the ascending aorta was approximately 4 cm greater than that
of the aortic valve during diastole. The thicknesses of the
interventricular septum (IVS) and ventricular wall were determined
during diastole. Aside from the maximum thickness, the representative
thickness of the IVS, which is usually the thickness of the point 25 mm
under the right coronary sinus nadir, was also recorded to indicate the
overall thickness. The LVOT gradient was calculated using the simplified
Bernoulli equation. The ventricular ejection fraction measurements were
determined according to the American Society of Echocardiography
recommendations. These methods have been provided in greater detail in
our previous publication.8