L Ferasin1, M Faena, S M Henderson, K Langford, P G G Darke. 1. University of Bristol, Department of Clinical Veterinary Science, Division of Companion Animals, Langford House, Langford, Bristol BS40 5DU.
Abstract
OBJECTIVES: To assess the ventricular rate response of rate-adaptive (VVIR) pacemakers in dogs using a multi-stage exercise test. METHODS: The rate-responsiveness of VVIR pacemakers was assessed in seven dogs with complete atrioventricular (AV) block and implanted with various models of pulse generators (six motion sensors and one automatic dual-sensor rate-response pacemaker). Response activity was assessed with a multi-stage exercise test on a treadmill. Atrial and ventricular rate were analysed retrospectively at the end of the test and the AV ratio was calculated after each minute of exercise. RESULTS: During exercise, the mean (sd) AV ratio recorded in all paced dogs was 1.7 (0.5) (expected physiological ratio 1.0), although a variety of individual performances was observed. A poor response (AV ratio 2.8 [0.2]) was obtained with the automatic dual-sensor pacemaker, suggesting that this type of rate-responsive device may not be indicated for implantation in dogs with complete AV block. The overall AV ratio for the six dogs implanted with motion sensors was 1.4 (0.2), showing a better performance of these pacemakers during exercise. CLINICAL SIGNIFICANCE: This multi-stage exercise test represents an easy and repeatable method for assessing the accuracy of rate-responsive sensors and offers valuable information for the correct setting of VVIR pacemakers in dogs.
OBJECTIVES: To assess the ventricular rate response of rate-adaptive (VVIR) pacemakers in dogs using a multi-stage exercise test. METHODS: The rate-responsiveness of VVIR pacemakers was assessed in seven dogs with complete atrioventricular (AV) block and implanted with various models of pulse generators (six motion sensors and one automatic dual-sensor rate-response pacemaker). Response activity was assessed with a multi-stage exercise test on a treadmill. Atrial and ventricular rate were analysed retrospectively at the end of the test and the AV ratio was calculated after each minute of exercise. RESULTS: During exercise, the mean (sd) AV ratio recorded in all paced dogs was 1.7 (0.5) (expected physiological ratio 1.0), although a variety of individual performances was observed. A poor response (AV ratio 2.8 [0.2]) was obtained with the automatic dual-sensor pacemaker, suggesting that this type of rate-responsive device may not be indicated for implantation in dogs with complete AV block. The overall AV ratio for the six dogs implanted with motion sensors was 1.4 (0.2), showing a better performance of these pacemakers during exercise. CLINICAL SIGNIFICANCE: This multi-stage exercise test represents an easy and repeatable method for assessing the accuracy of rate-responsive sensors and offers valuable information for the correct setting of VVIR pacemakers in dogs.
Authors: Lisa De Lange; Glenn Van Steenkiste; Ingrid Vernemmen; Lisse Vera; Kristel M C Cromheeke; Ulla Walser; Hans Meert; Annelies Decloedt; Gunther van Loon Journal: J Vet Intern Med Date: 2021-11-06 Impact factor: 3.333