Two-dimensionally-guided M-mode and pulsed wave Doppler echocardiographic evaluation of the ventricles of apparently healthy cats

Abstract

Objective: To determine two-dimensionally-guided (2D-guided) M-mode and pulsed-wave (PW) Doppler echocardiographic reference intervals range of healthy non-sedated cats.

Animals: Fifty-three healthy, unsedated domestic cats.

Materials and methods: Cats were interrogated via standard imaging planes with 2D-guided PW Doppler, using 5.0 and 7.5 MHz duplex imaging transducers. Left ventricular (LV) M-mode measurements and intracardiac PW Doppler data were acquired using ACVIM guidelines for echocardiography. Doppler variables of the same region, measured from different views, were compared for agreement where appropriate. Descriptive statistics were provided for all measured variables. Statistical comparisons of selected M-mode and PW Doppler echocardiographic variables and correlations with weight or age were made, with significance set at P < 0.01.

Results: Most cats (42/51) had diastolic LV septal and posterior wall diastolic dimensions <4.5 mm (maximum = 5.7 mm). Only septal diastolic wall dimension correlated weakly with body weight (ρ = 0.36). Median peak transvalvular velocities (m/s) were: aorta 1.04 (range: 0.77-1.40); LV inflow 0.60 (range: 0.43-0.95) (E wave), 0.47 (range: 0.32-0.76) (A wave), RV inflow 0.56 (range: 0.37-0.85), pulmonic valve (right) 0.96 (range: 0.65-1.21). For mitral valve inflow, the E and A waves were usually separately measurable at heart rates ≈ <180/min, merging into a single diastolic wave (EA) at heart rates ≈ >190/min. Peak E wave velocity correlated with heart rate. No variables correlated with age.

Conclusions: Our study provides comprehensive 2D-guided echocardiographic M-mode and PW Doppler reference data for apparently healthy cats.