TY - JOUR

T1 - Changes in heart rate, arrhythmia frequency, and cardiac biomarker values in horses during recovery after a long-distance endurance ride

AU - Madsen, Mette Flethøj

AU - Kanters, Jørgen K.

AU - Haugaard, Maria Mathilde

AU - Pedersen, Philip Juul

AU - Carstensen, Helena

AU - Balling, Johanne D.

AU - Olsen, Lisbeth Høier

AU - Buhl, Rikke

PY - 2016/5/1

Y1 - 2016/5/1

N2 - OBJECTIVE: To evaluate heart rate, heart rate variability, and arrhythmia frequency as well as changes in cardiac biomarker values and their association with heart rate in horses before and after an endurance ride.DESIGN:Cross-sectional study.ANIMALS:28 Arabian horses competing in a 120- or 160-km endurance ride.PROCEDURES:ECG recordings were obtained from each horse before (preride) and after (recovery) an endurance ride to evaluate changes in heart rate and the SD of normal R-R intervals (SDNN) during the initial 12 hours of recovery. Frequencies of supraventricular and ventricular premature complexes before and after the ride were evaluated. Blood samples were obtained before the ride and twice during recovery. Hematologic analyses included measurement of serum cardiac troponin I concentration and creatine kinase isoenzyme MB activity.RESULTS:Heart rate was significantly increased and SDNN was decreased during the recovery versus preride period. Frequency of ventricular premature complexes increased during recovery, albeit not significantly, whereas frequency of supraventricular premature complexes was not significantly different between preride and recovery periods. Serum cardiac troponin I concentration and creatine kinase isoenzyme MB activity were significantly increased in the recovery versus preride period. No associations were identified between cardiac biomarkers and velocity, distance, or mean heart rate.CONCLUSIONS AND CLINICAL RELEVANCE:Heart rate increased and SDNN decreased in horses after completion of an endurance ride. These and other cardiac changes suggested that prolonged exercise such as endurance riding might have cardiac effects in horses. Additional studies are needed to clarify the clinical relevance of the findings.

AB - OBJECTIVE: To evaluate heart rate, heart rate variability, and arrhythmia frequency as well as changes in cardiac biomarker values and their association with heart rate in horses before and after an endurance ride.DESIGN:Cross-sectional study.ANIMALS:28 Arabian horses competing in a 120- or 160-km endurance ride.PROCEDURES:ECG recordings were obtained from each horse before (preride) and after (recovery) an endurance ride to evaluate changes in heart rate and the SD of normal R-R intervals (SDNN) during the initial 12 hours of recovery. Frequencies of supraventricular and ventricular premature complexes before and after the ride were evaluated. Blood samples were obtained before the ride and twice during recovery. Hematologic analyses included measurement of serum cardiac troponin I concentration and creatine kinase isoenzyme MB activity.RESULTS:Heart rate was significantly increased and SDNN was decreased during the recovery versus preride period. Frequency of ventricular premature complexes increased during recovery, albeit not significantly, whereas frequency of supraventricular premature complexes was not significantly different between preride and recovery periods. Serum cardiac troponin I concentration and creatine kinase isoenzyme MB activity were significantly increased in the recovery versus preride period. No associations were identified between cardiac biomarkers and velocity, distance, or mean heart rate.CONCLUSIONS AND CLINICAL RELEVANCE:Heart rate increased and SDNN decreased in horses after completion of an endurance ride. These and other cardiac changes suggested that prolonged exercise such as endurance riding might have cardiac effects in horses. Additional studies are needed to clarify the clinical relevance of the findings.

U2 - 10.2460/javma.248.9.1034

DO - 10.2460/javma.248.9.1034

M3 - Journal article

C2 - 27074612

VL - 248

SP - 1034

EP - 1042

JO - Journal of the American Veterinary Medical Association

JF - Journal of the American Veterinary Medical Association

SN - 0003-1488

IS - 9

ER -