Danielle N Smith1, Karsten E Schober. 1. Department of Veterinary Clinical Sciences, The Ohio State University College of Veterinary Medicine, 601 Vernon L Tharp St. Columbus, OH 43210, USA.
Abstract
BACKGROUND: Evaluation of left ventricular (LV) diastole is clinically important in cats with heart disease. Diastolic dysfunction is a main characteristic of feline cardiomyopathy and is associated with clinical signs and poor outcome. Numerous echocardiographic indices characterizing LV diastole exist, of which Doppler variables of transmitral flow and mitral annular motion are used most often. However, rapid heart rate (HR), a common finding in cats examined in the veterinary hospital environment, may cause summation of flow waves limiting interpretation of diastolic function. OBJECTIVE: To evaluate the effects of vagal maneuvers (gentle eyeball pressure and nasal planum massage) on HR and Doppler variables of LV diastolic filling. ANIMALS: Twenty-four healthy client-owned cats with summated transmitral flow waves at baseline. METHODS: Prospective observational study. Transthoracic echocardiography was performed and Doppler transmitral and mitral annular tissue Doppler velocities recorded both before and during vagal maneuvers. Data were compared using a paired t-test. RESULTS: Application of vagal maneuvers temporarily decreased HR in all cats (mean reduction ± SD; 42 ± 22 bpm). The duration of HR reduction (<5 s, 5-10 s, and >10-15 s) was evenly distributed among groups (8 cats in each). Summated Doppler transmitral flow and mitral annular tissue velocity waves were separated during vagal maneuvers in 71% and 72% of cats, respectively. No adverse effects were observed. CONCLUSIONS: Vagal maneuvers may be utilized as a simple non-pharmacologic tool in the Doppler evaluation of LV diastolic function in healthy cats.
BACKGROUND: Evaluation of left ventricular (LV) diastole is clinically important in cats with heart disease. Diastolic dysfunction is a main characteristic of feline cardiomyopathy and is associated with clinical signs and poor outcome. Numerous echocardiographic indices characterizing LV diastole exist, of which Doppler variables of transmitral flow and mitral annular motion are used most often. However, rapid heart rate (HR), a common finding in cats examined in the veterinary hospital environment, may cause summation of flow waves limiting interpretation of diastolic function. OBJECTIVE: To evaluate the effects of vagal maneuvers (gentle eyeball pressure and nasal planum massage) on HR and Doppler variables of LV diastolic filling. ANIMALS: Twenty-four healthy client-owned cats with summated transmitral flow waves at baseline. METHODS: Prospective observational study. Transthoracic echocardiography was performed and Doppler transmitral and mitral annular tissue Doppler velocities recorded both before and during vagal maneuvers. Data were compared using a paired t-test. RESULTS: Application of vagal maneuvers temporarily decreased HR in all cats (mean reduction ± SD; 42 ± 22 bpm). The duration of HR reduction (<5 s, 5-10 s, and >10-15 s) was evenly distributed among groups (8 cats in each). Summated Doppler transmitral flow and mitral annular tissue velocity waves were separated during vagal maneuvers in 71% and 72% of cats, respectively. No adverse effects were observed. CONCLUSIONS: Vagal maneuvers may be utilized as a simple non-pharmacologic tool in the Doppler evaluation of LV diastolic function in healthy cats.
Authors: Ingrid van Hoek; Hannah Hodgkiss-Geere; Elizabeth F Bode; Julie Hamilton-Elliott; Paul Mõtsküla; Valentina Palermo; Yolanda Martinez Pereira; Geoff J Culshaw; Jeremy Laxalde; Joanna Dukes-McEwan Journal: J Vet Intern Med Date: 2020-10-29 Impact factor: 3.333