Aortic annular plane systolic excursion in cats with hypertrophic cardiomyopathy.

Abstract

BACKGROUND: Impairment of left ventricular (LV) longitudinal function is an early marker of systolic dysfunction in hypertrophic cardiomyopathy (HCM). Aortic annular plane systolic excursion (AAPSE) is a measure of LV longitudinal function in people that has not been evaluated in cats. HYPOTHESIS: Aortic annular plane systolic excursion is lower in cats with HCM compared to control cats, and cats in stage C have the lowest AAPSE. ANIMALS: One hundred seventy-five cats: 60 normal, 61 HCM stage B and 54 HCM stage C cats. MATERIALS: Multicenter retrospective case-control study. Electronic medical records from 4 referral hospitals were reviewed for cats diagnosed with HCM and normal cats. HCM was defined as LV wall thickness &#x2265;6&#x2009;mm and normal cats &#x2264;5&#x2009;mm. M-mode bisecting the aorta in right parasternal short-axis view was used to measure AAPSE. RESULTS: Aortic annular plane systolic excursion was lower in HCM cats compared to normal cats (3.9&#x2009;&#xb1;&#x2009;0.9&#x2009;mm versus 4.6&#x2009;&#xb1;&#x2009;0.9&#x2009;mm, P&#x2009;<&#x2009;.001) and was lowest in HCM stage C (2.4&#x2009;&#xb1;&#x2009;0.6&#x2009;mm, P&#x2009;<&#x2009;.001). An AAPSE <2.9&#x2009;mm gave a sensitivity of 83% (95% CI 71%-91%) and specificity of 92% (95% CI 82%-97%) to differentiate HCM stage C from stage B. AAPSE correlated with mitral annular plane systolic excursion (r&#x2009;=&#x2009;.6 [.4-.7], P&#x2009;<&#x2009;.001), and atrial fractional shortening (r&#x2009;=&#x2009;.6 [.5-.7], P&#x2009;<&#x2009;.001), but showed no correlation with LV fractional shortening. CONCLUSIONS AND CLINICAL IMPORTANCE: Aortic annular plane systolic excursion is an easily acquired echocardiographic variable and might be a new measurement of LV systolic performance in cats with HCM.