Two-dimensional and M-mode echocardiographic methods for assessing left ventricular wall thickness cannot be used interchangeably, particularly in cats with hypertrophic cardiomyopathy (P < .001).
Cross-Sectional (n=280)
No
Does the choice of echocardiographic imaging view and mode affect left ventricular wall-thickness measurements in normal cats and cats with hypertrophic cardiomyopathy?
Two-dimensional and M-mode echocardiographic methods yield significantly different measurements of left ventricular wall thickness in cats with HCM and cannot be used interchangeably.
p-value: p=<.001
Abstract Background Echocardiographic measurements of left ventricular free wall (LVFW) and interventricular septum (IVS) thickness are essential for diagnosing hypertrophic cardiomyopathy (HCM). Hypothesis/Objectives To evaluate agreement between different imaging views and modes for assessing LV wall thickness in cats. We hypothesized that there is clinically relevant bias between methods, and that results cannot be used interchangeably. Animals Two-hundred eighty cats; 140 controls and 140 with subclinical HCM. Methods Retrospective, single-center, and cross-sectional study. End-diastolic IVS and LVFW thickness was evaluated by 2-dimensional (2D) and time-motion mode (M-mode) echocardiography, from right parasternal long-axis (RPLax) and right parasternal short-axis (RPSax) views: method-1 (M1), RPLax using 2D; M2, RPLax using M-mode; M3, RPSax using 2D; and M4, RPSax using M-mode. Using 2D images, the thickest portion of the LV wall was measured. Methods were compared using repeated measurement ANOVA on ranks and the Bland–Altman method with bias and 95% limits of agreement (95% LOA). Results In controls, IVS thickness was not different among the 4 methods (P = .67; bias 0.04-0.10 mm, 95% LOA −1.09 to 1.28 mm); whereas LVFW thickness was (P .001) using M-mode compared to 2D (bias 0.22-0.30 mm; 95% LOA −0.81 to 1.25 mm). In HCM cats, thickness of the IVS (bias −1.07 to −1.13 mm; 95% LOA −3.05 to 0.84 mm) and LVFW (bias 0.22 to −.27 mm; 95% LOA −2.09 to 2.03 mm) was different among methods (P .001). Conclusions and clinical importance Two-dimensional and M-mode echocardiographic methods in the assessment of LV wall thickness cannot be used interchangeably, particularly in cats with HCM.
Grosso et al. (Sun,) conducted a cross-sectional in Hypertrophic cardiomyopathy (n=280). 2-dimensional and M-mode echocardiography vs. Different imaging views and modes was evaluated on Agreement between different imaging views and modes for assessing left ventricular wall thickness (p=<.001). Two-dimensional and M-mode echocardiographic methods for assessing left ventricular wall thickness cannot be used interchangeably, particularly in cats with hypertrophic cardiomyopathy (P < .001).