Prevalence of aortic dilation in hypertrophic cardiomyopathy

Abstract

Recent studies have suggested that hypertrophic cardiomyopathy (HCM) is associated with increased stiffness of the aorta. However, a potential relationship between HCM and aortic dilation has not been established. Aorta size was characterized in 223 consecutive patients diagnosed with HCM. Aorta size was measured at the level of the sinuses (n = 223) and ascending aorta (n = 115) using the parasternal long-axis echocardiographic view. Hypertrophy pattern, maximum wall thickness, and left ventricular outflow tract gradient were measured. Aortic dilation was defined using previously published criteria that control for body surface area, age, and gender. Mean aorta size among the HCM cohort was 33.0 ± 5.0 mm at the sinuses and 34.0 ± 5.0 at the tubular aorta. Using the age-based nomogram controlling for body surface area, 10 (4.5%) of the study population had dilated aortas at the sinuses of Valsalva. Only gender (10/10 male in dilated group, 127/213 in non-dilated group, p = 0.008) was associated with dilation, while characteristics of HCM (LVOT obstruction, maximum wall thickness, hypertrophy pattern) were not. Use of other criteria for dilation did not result in an association with HCM characteristics. Aortic dilation in HCM does not seem to occur more frequently than in the general population and is not related to the extent of hypertrophy or LVOT obstruction.

Keywords: Aorta; dilation; hypertrophic cardiomyopathy.

Figure 1

Aorta size at the sinuses of Valsalva plotted against the 95% upper confidence limit regression line derived from Roman et al. 9 for age less than 40 (A) and greater than 40 (B).