Left and right atrial speckle tracking: Comparison of three methods of time reference gating.

BACKGROUND: Atrial function has a close interdependence with ventricular function and plays a central role in maintaining optimal cardiac function. There are two well-defined timing methods used to determine the start point. The aim of this prospective study was to objectively assess the influence of gating method selection on reported left and right strain values within the same group of healthy subjects. METHODS: 101 volunteers (44 male, 57 female) had adequate tracking for analysis on TomTec Imaging Systems (Unterschleissheim, Germany). The median age was 41 years (range 19-79 years, interquartile range 30-52 years). Atrial strain by 2D-speckle tracking echocardiography was evaluated using two commonly applied zero baseline time reference methods: R-R gating and P-P gating, in addition to volume gating (defining end-systole at the atrial maximum and end-diastole at the atrial minimum). RESULTS: True atrial minimum occurred prior to the onset of the QRS in most healthy volunteers. There was a significant difference for LA and RA reservoir strain between volume gating and R-R gating (mean difference, 4.63%; P < .001 for LA; mean difference, 4.23%; P < .001 for RA), as well as volume gating and P-P gating (mean difference, 5.26%; P < .001 for LA; mean difference, 6.24%; P < .001 for RA). Noticeably, reservoir strain was comparable between R-R gating and P-P gating (mean difference, 0.58%, P = .06) in LA, but not on RA (mean difference, 2.02%, P < .001). CONCLUSIONS: There was variability in atrial strain values depending on the zero baseline time reference method used.

Atrial function and geometry differences in transthyretin versus immunoglobulin light chain amyloidosis: a cardiac magnetic resonance study.

To determine the differences in left atrial (LA) function and geometry assessed by cardiac magnetic resonance (CMR) between transthyretin (ATTR) and immunoglobulin light chain (AL) cardiac amyloidosis (CA). We performed a retrospective analysis of 54 consecutive patients (68.5% male, mean age 67 ± 11 years) with confirmed CA (24 ATTR, 30 AL) who underwent comprehensive CMR examinations. LA structural and functional assessment including LA volume, LA sphericity index, and LA strain parameters were compared between both subtypes. In addition, 15 age-matched controls were compared to all groups. Patients with ATTR-CA were older (73 ± 9 vs. 62 ± 10 years, p < 0.001) and more likely to be male (83.3% vs. 56.7%, p = 0.036) when compared to AL-CA. No significant difference existed in LA maximum volume and LA sphericity index between ATTR-CA and AL-CA. LA minimum volumes were larger in ATTR-CA when compared with AL-CA. There was a significant difference in LA function with worse strain values in ATTR vs AL: left atrial reservoir [7.4 (6.3-12.8) in ATTR vs. 13.8 (6.90-24.8) in AL, p = 0.017] and booster strains [3.6 (2.6-5.5) in ATTR vs. 5.2 (3.6-12.1) in AL, p = 0.039]. After adjusting for age, LA reservoir remained significantly lower in ATTR-CA compared to AL-CA (p = 0.03), but not LA booster (p = 0.16). We demonstrate novel differences in LA function between ATTR-CA and AL-CA despite similar LA geometry. Our findings of more impaired LA function in ATTR may offer insight into higher AF burden in these patients.

Abnormal ventricular contractile pattern associated with late systolic mitral prolapse: a two-dimensional speckle tracking study.

We sought to study the mechanics of ventricular contraction in patients with and outward basal movement. Using echocardiographic parasternal long-axis views we retrospectively screened 760 echocardiograms to enroll 50 individuals with late systolic bileaflet prolapse, papillary muscle traction, and outward movement of the sub-annular base and posterior mitral annulus in late systole. Two-dimensional speckle tracking echocardiography was used to analyze the mechanics of contraction. Global and regional longitudinal strain values between the study group and 45 healthy control subjects were compared. The study group's global strain was lower compared to the control group. We identified a pattern of weak contraction of the inferior and lateral walls in the late systolic bileaflet prolapse group. The weakest segment in the study group was the basal-inferolateral segment (- 15.8% vs. - 21.5%, p < 0.001). There was no relationship between the mitral annular size, degree of leaflet prolapse, or degree of basal weakness. Late systolic bileaflet mitral prolapse and papillary muscle traction are accompanied by an outward movement of the sub-annular base and posterior mitral annulus in late systole. We demonstrated an abnormal contractile pattern in these ventricles characterized by a weaker contraction of the base, most significant at the inferolateral segment. This weakness of contraction may contribute to the outward movement of the base and posterior annulus.

Right Atrial Deformation Using Cardiovascular Magnetic Resonance Myocardial Feature Tracking Compared with Two-Dimensional Speckle Tracking Echocardiography in Healthy Volunteers.

Speckle tracking echocardiography (STE), and more recently, cardiovascular magnetic resonance myocardial feature tracking (CMR-FT) provides insight into all phases of atrial function. The aim of our study was to compare all phases of RA strain using CMR-FT and STE and also assess the relationship between RA and LA strain. A total of 61 healthy volunteers with mean age of 45 ± 13 years had adequate tracking for analysis on CMR-FT and 2D-STE. Females had larger RA reservoir strain (39 ± 15% vs. 32 ± 13%, p = 0.046) and conduit strain (26 ± 12% vs. 20 ± 9%, p = 0.03) when compared to males, but was not the case with booster strain (14 ± 7% vs. 12 ± 6%, p = 0.45). In comparison with STE derived strain, the RA reservoir and conduit strain were not significantly different between CMR-FT and the three echocardiography gating methods (p > 0.05 for all). Noticeably, there were no significant differences in strain and strain rate between RA and LA function using CMR-FT (p > 0.05 for all). RA strain and strain rate using CMR-FT had fair and good intra- and inter-observer reproducibility and had superior reproducibility compared to STE derived strain.

Normal left atrial strain and strain rate using cardiac magnetic resonance feature tracking in healthy volunteers.

AIMS: The aim of our study was to establish normal ranges for left atrial (LA) strain and strain rate using cardiac magnetic resonance feature tracking (CMR-FT), LA sphericity index, and to compare LA strain using CMR-FT with 2D-speckle tracking echocardiography (STE) in a healthy population. METHODS AND RESULTS: A total of 112 volunteers (45 male, 67 female) had adequate tracking for analysis on CMR-FT (Circle Cardiovascular Imaging, Calgary, Canada). The median age was 42 years (range 19-79 years, interquartile range 30-53 years). LA reservoir, conduit, booster strain, strain rate using CMR-FT, and sphericity index were evaluated. Of the 112 volunteers, 91 patients had adequate tracking on 2D-STE using three commonly applied zero-baseline time reference methods: R-R gating, P-P gating, and volume gating (defining end-systole at the LA maximum and end-diastole at the LA minimum). The LA strain, strain rate using CMR-FT, and sphericity index were reported and comparable between both genders (P > 0.05 for all). The LA booster function including strain and strain rate increased significantly with age (P < 0.001 for all), while the LA conduit function gradually decreased. In comparison with STE, the LA reservoir strain was comparable between CMR and volume-gating methods (38.48 ± 9.31 vs. 36.77 ± 6.46; P = 0.13) but not with R-R and P-P gating methods (P < 0.001 for all). LA strain, strain rate, and sphericity index using CMR-FT had good intraobserver and interobserver reproducibility. CONCLUSION: LA strain, strain rate using CMR-FT, and sphericity index can be quickly assessed with good intraobserver and interobserver reproducibility.