J Vet Intern Med. 2026 Sep 1;40(5):aalag224. doi: 10.1093/jvimsj/aalag224.
ABSTRACT
BACKGROUND: Consensus is lacking on which endocardial borders to include when measuring left ventricular wall thickness (LVWT) in cats.
HYPOTHESIS/OBJECTIVES: The number of endocardial borders included can influence whether an individual cat is classified as having hypertrophic cardiomyopathy (HCM) or not.
ANIMALS: Fifty-two cats that previously were diagnosed as either healthy, equivocal for HCM, or having an HCM phenotype.
METHODS: Single-center retrospective cross-sectional study. Three observers measured LVWT using 4 different LVWT measurement protocols: leading edge-to-leading edge (L-L); leading edge-to-trailing edge, trailing edge-to-leading edge, and trailing edge-to-trailing edge for the interventricular septum and L-L and trailing edge-to-leading edge methods for the left ventricular free wall (LVFW). Measurements were made using stored echocardiographic images on 2 occasions by 2 observers. A Friedman test and post-hoc Wilcoxon signed rank test with Bonferroni correction were performed to detect differences between measurement techniques.
RESULTS: Interventricular septum (IVS) wall thickness was significantly larger for leading-edge-to-trailing-edge measurement (median and [interquartile range (IQR)]: 5.5 [3.8-7.2] millimeters) compared with other methods (P < .001). The trailing-edge-to-leading-edge method produced significantly smaller results (4.3 [IQR, 3.4-6.2] millimeters for the interventricular septum and 4.8 [IQR, 3.4-6.2] millimeters for the LVFW) compared with other methods (P < .001). Median IVS thickness measured as leading-edge-to-trailing-edge was 1.2 millimeters larger than when measured as trailing-edge-to-leading-edge.
CONCLUSIONS AND CLINICAL IMPORTANCE: LVWT varies depending on the number of endocardial borders included. The number of endocardial borders included in LVWT measurements should be standardized.
PMID:42820725 | PMC:PMC13628518 | DOI:10.1093/jvimsj/aalag224