{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T14:42:05Z","timestamp":1788273725671,"version":"build-2803163510"},"reference-count":23,"publisher":"Oxford University Press (OUP)","issue":"2","license":[{"start":{"date-parts":[[2026,3,24]],"date-time":"2026-03-24T00:00:00Z","timestamp":1774310400000},"content-version":"vor","delay-in-days":23,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100032443","name":"The Hong Kong Jockey Club","doi-asserted-by":"crossref","id":[{"id":"10.13039\/100032443","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,3,2]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>The frequency, characteristics, and relationship with performance of arrhythmias occurring during high-intensity exercise in Thoroughbred racehorses remain poorly understood.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Hypothesis\/Objectives<\/jats:title>\n                    <jats:p>Describe the frequency, characteristics, and association with subsequent race performance of arrhythmias occurring during intense exercise.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Animals<\/jats:title>\n                    <jats:p>Seventy-one racehorses competing in races sanctioned by the Hong Kong Jockey Club.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>Risk-based case\u2013control study. Single-lead ECGs were recorded during high-intensity trials using wearable devices. Ectopic depolarizations identified during warm-up, maximal exercise, and fast and slow recovery were characterized by frequency and morphology. Horses with ECG recordings obtained before a race were included. Race performance was classified as poor (finishing in the last 3 positions) or good (finishing in the first 3 positions). Associations between ECG variables and race performance were assessed using odds ratios.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>A total of 405 ECGs were recorded within 21\u00a0days before 1 or more race starts (82 poor- and 142 good-performance starts). Arrhythmias were detected in 73% and 81% of ECGs preceding good and poor performances, respectively. Ectopic beats during maximal exercise occurred in 57% of ECGs before good and in 70% before poor performances. The odds of performing poorly increased with each additional ectopic beat (odds ratio [OR], 1.15; 95% confidence interval [CI], 1.04-1.28; P\u00a0=\u00a0.01), and horses with any ectopic beat were nearly twice as likely to underperform (OR, 1.8; 95% CI, 0.86-3.81; P\u00a0=\u00a0.02).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions and clinical importance<\/jats:title>\n                    <jats:p>Ectopic beats are common and adversely associated with athletic performance. Electrocardiographic monitoring during intense exertion might enable detection of clinically important arrhythmias.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1093\/jvimsj\/aalag044","type":"journal-article","created":{"date-parts":[[2026,3,24]],"date-time":"2026-03-24T11:00:36Z","timestamp":1774350036000},"source":"Crossref","is-referenced-by-count":2,"title":["Cardiac arrhythmias during intense exercise in Thoroughbred racehorses: frequency and association with subsequent race performance"],"prefix":"10.1093","volume":"40","author":[{"given":"Emmanuelle","family":"van Erck-Westergren","sequence":"first","affiliation":[{"name":"Equine Sports Medicine Practice , Waterloo ,","place":["Belgium"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stephen","family":"O\u2019Connor","sequence":"additional","affiliation":[{"name":"Hong Kong Jockey Club, Department of Veterinary Clinical Services, Sha Tin Equine Hospital , Sha Tin, New Territories ,","place":["Hong 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