Timolol 0.5% ophthalmic solution influences cardiac function in healthy cats.

Objectives: The aim of this study was to ascertain the effect of a drop of timolol 0.5% ophthalmic solution on the systolic function of the left ventricle (LV) and left atrium (LA), and to confirm if timolol helped appraisal of diastolic function by reducing heart rate (HR) and separating the transmitral outflow waves from tissue Doppler imaging (TDI).

Methods: A total of 41 client-owned healthy cats underwent two echocardiograms 20 mins apart.

Tissue motion annular displacement to assess the left ventricular systolic function in healthy cats.

The tissue motion annular displacement (TMAD) measures the longitudinal displacement of the mitral annulus during systole, using speckle-tracking echocardiography (STE). The main objective was to determine the TMAD means in healthy cats, exploring the correlations with systolic surrogates. The influence of age, body surface area (BSA), heart rate, and systemic blood pressure on the indices was also analyzed.

Assessment of heart rate turbulence in dogs with myxomatous mitral valve disease.

Background: Myxomatous mitral valve degeneration (MMVD) is the most common heart disease affecting small dogs, it reduces cardiac output resulting in compensatory adaptation of the autonomic nervous system. Chronically, it leads to reduced heart rate variability (HRV) which is an accurate marker for autonomic balance. More than two decades ago in human medicine an indicator of autonomic balance that happens after a premature ventricular beat, it was described as heart rate turbulence (HRT).