Ultrasonographic assessment of aortic elasticity in hypertensive cats

Introduction: Feline systemic hypertension (SH) represents a widespread and commonly under-recognized condition that is frequently linked with kidney disease and endocrine diseases. Among the secondary complications chronic SH is the reduction of arterial elasticity. Objective: To compare the ultrasound-derived aortic elasticity (AoSt%) of the ascending aorta between hypertensive and normotensive cats and to establish an AoSt% cutoff value to discriminate between hypertensive and normotensive cats. Methods: A prospective, observational case-control study was conducted on 40 cats with diseases or clinical signs suggestive of systemic hypertension. Hypertensive and normotensive cats were established using averaged systolic blood pressure (SBP) measurements recorded using high-definition oscillometry. M-mode echocardiography was used to measure ascending aorta systolic (CrAoDs) and diastolic (CrAoDd) diameters. Aortic distensibility was estimated by the Aortic Strain with the following formula: AoSt% = [(CrAoDs - CrAoDd)/CrAoDd] X 100 Results: median AoSt% in hypertensive cats was significantly lower than in normotensive cats (AoSt%: 13.3 % vs 18.9 %, respectively, p < 0.01). The best AoSt% cutoff value to discriminate hypertensive status was ≤18.4%, (AUC = 0.81; sensitivity = 90%; specificity = 60%). Conclusion: Ultrasonographic evaluation of AoSt% can be considered a non-invasive index of vascular stiffness and could be used to detect systemic hypertension in cats. Keywords: Feline systemic hypertension, blood pressure cat, aortic strain, AoSt%, ultrasound, arterial stiffness, chronic kidney disease, cardiovascular biomarkers, veterinary echocardiography