Clinical usefulness of cardiac event recording in dogs and cats examined because of syncope, episodic collapse, or intermittent weakness: 60 cases (1997-1999)

Objective-To determine the clinical usefulness of cardiac evens recording i n evaluating dogs and cats with unexplained syncope, episodic collapse, or intermittent weakness. Design-Retrospective study. Animals-58 dogs and 2 cats. Procedure-Medical records and electrocardiographic rhythm strips obtained b y cardiac event recordings were reviewed. Cardiac rhythm data from the even t recordings were classified as diagnostic or nondiagnostic. Diagnostic yie ld was calculated by dividing the number of animals for which cardiac event recording was diagnostic by the total number of animals undergoing cardiac event recording. Results-For 51 animals, cardiac event recording was classified as diagnosti c; therefore, overall diagnostic yield was 85%. Diagnostic yield was lower for animals without underlying structural heart disease (75.5%) than for an imals with structural heart disease (95.6%). A specific arrhythmia was iden tified as the cause of clinical signs in 18 of the 51 (35%) animals for whi ch cardiac event recording was diagnostic. Cardiac arrhythmia was definitiv ely excluded as the cause of clinical signs in the remaining 33 (65%) anima ls in which cardiac event recording was diagnostic. Conclusions and Clinical Relevance-Results indicate that cardiac event reco rding had a high diagnostic yield in dogs and cats examined because of unex plained syncope, episodic collapse, or transient weakness and ataxia, regar dless of whether animals did or did not have an underlying structural heart disease. Diagnostic yield of cardiac event recording was higher than that reported previously for Holter monitoring.