Assessment of Cardiac Functions in Patients With Keratoconus Using Two-Dimensional Speckle-Tracking Echocardiography and Three-Dimensional Echocardiography.

Background: Keratoconus (KC) is a multifactorial disease characterized by progressive corneal thinning and structural deformation. Despite being an ophthalmological disorder, KC is proposed to have systemic implications. The aim of this study was to evaluate cardiac functions in KC patients by two-dimensional (2D) speckle-tracking echocardiography (STE) and three-dimensional (3D) echocardiography.

Methods: The study included 45 consecutive patients with KC (mean age: 37.6 ± 12.6 years, 23 male) and 42 healthy controls (mean age: 38.1 ± 8.6 years, 23 male). All participants underwent standard transthoracic echocardiography, 3D echocardiography, and 2D STE to evaluate cardiac functions.

Results: Although there were no significant differences in the conventional echocardiographic markers regarding left ventricular (LV) and right ventricular (RV) functions except tricuspid annular plane systolic excursion; patients with KC had significantly lower LV global longitudinal strain (GLS) compared to controls (-17.75 ± 2.43% vs. -19.71 ± 1.97%, p < 0.001). They also had lower RV GLS, left and right atrial reservoir, and conduit strains, although the differences were not statistically significant. LV GLS negatively correlated with corneal densitometry in KC patients. Linear regression analysis showed that KC was independently associated with LV GLS when adjusted for age and sex.

Conclusions: Patients with KC had significantly lower LV GLS, suggesting the presence of a subclinical LV dysfunction in these patients, which supports that KC may be a component of a systemic disease.