Influence of heart rate on myocardial function using two-dimensional speckle-tracking echocardiography in healthy dogs.

Abstract

OBJECTIVE:

The objective of this study was to evaluate the influence of heart rate (HR) on myocardial function assessed by two-dimensional speckle-tracking echocardiography (2D-STE) in healthy dogs.

ANIMALS:

Thirteen healthy beagle dogs.

METHODS:

Animals were anesthetized and HR was controlled with right atrial pacing. Myocardial function of each dog was assessed using 2D-STE at pacing rates of 120, 140, 160, and 180 bpm.

RESULTS:

All strain and strain rate variables in the longitudinal, circumferential, and radial directions were not significantly different between pacing rates. Peak early diastolic torsion rate at 180 bpm was significantly increased compared with that at 120 bpm (P = 0.003).

CONCLUSION:

Torsion rate in early diastole was elevated at 180 bpm, which may reflect improved myocardial relaxation with higher HR. Changes in left ventricular torsion during tachycardia may play an important role in preserving stroke volume in the presence of shortened ejection and filling times.

• Authors: Ryohei Suzuki, Hirotaka Matsumoto, Takahiro Teshima, Hidekazu Koyama
• Journal: Journal of veterinary cardiology : the official journal of the European Society of Veterinary Cardiology (J Vet Cardiol) Vol. 15 Issue 2 Pg. 139-46 (Jun 2013) ISSN: 1875-0834 [Electronic] Netherlands
• PMID: 23643819 (Publication Type: Journal Article)
• Copyright: Copyright © 2013 Elsevier B.V. All rights reserved.

Topics

• Animals
• Dogs (physiology)
• Echocardiography (methods, veterinary)
• Heart Rate (physiology)