Usefulness of automatic assessment for longitudinal strain to diagnose wild-type transthyretin amyloid cardiomyopathy.

Background: Left ventricular (LV) apical sparing by transthoracic echocardiography (TTE) has not been widely accepted to diagnose transthyretin amyloid cardiomyopathy (ATTR-CM), because it is time consuming and requires a level of expertise. We hypothesized that automatic assessment may be the solution for these problems. Methods-and-Results: We enrolled 63 patients aged ≥70 years who underwent 99mTc-labeled pyrophosphate (99mTc-PYP) scintigraphy on suspicion of ATTR-CM and performed TTE by EPIQ7G, and had enough information for two-dimensional speckle tracking echocardiography at Kumamoto University Hospital from January 2016 to December 2019. LV apical sparing was described as a high relative apical longitudinal strain (LS) index (RapLSI). Measurement of LS was repeated using the same apical images with three different measurement packages as follows: (1) full-automatic assessment, (2) semi-automatic assessment, and (3) manual assessment. The calculation time for full-automatic assessment (14.7 ± 1.4 sec/patient) and semi-automatic assessment (66.7 ± 14.4 sec/patient) were significantly shorter than that for manual assessment (171.2 ± 59.7 sec/patient) (p < 0.01 for both). Receiver operating characteristic curve analysis showed that the area under curve of the RapLSI evaluated by full-automatic assessment for predicting ATTR-CM was 0.70 (best cut-off point; 1.14 [sensitivity 63%, specificity 81%]), by semi-automatic assessment was 0.85 (best cut-off point; 1.00 [sensitivity, 66%; specificity, 100%]) and by manual assessment was 0.83 (best cut-off point; 0.97 [sensitivity, 72%; specificity, 97%]). Conclusion: There was no significant difference between the diagnostic accuracy of RapLSI estimated by semi-automatic assessment and that estimated by manual assessment. Semi-automatically assessed RapLSI is useful to diagnose ATTR-CM in terms of rapidity and diagnostic accuracy.

Utility of left atrial and ventricular strain for diagnosis of transthyretin amyloid cardiomyopathy in aortic stenosis.

AIMS: To clarify the usefulness of left atrial (LA) function and left ventricular (LV) function obtained by two-dimensional (2D) speckle tracking echocardiography to diagnose concomitant transthyretin amyloid cardiomyopathy (ATTR-CM) in patients with aortic stenosis (AS). METHODS AND RESULTS: We analysed 72 consecutive patients with moderate to severe AS who underwent 99m Tc-pyrophosphate (PYP) scintigraphy at Kumamoto University Hospital from January 2012 to September 2020. We divided these 72 patients into 2 groups based on their 99m Tc-PYP scintigraphy positivity or negativity. Among 72 patients, 16 patients (22%) were positive, and 56 patients (78%) were negative for 99m Tc-PYP scintigraphy. In clinical baseline characteristics, natural logarithm troponin T was significantly higher in the 99m Tc-PYP scintigraphy-positive than scintigraphy-negative group (-2.9 ± 0.5 vs. -3.5 ± 0.8 ng/mL, P < 0.05). In conventional echocardiography, the severity of AS was not significantly different between these two groups. In 2D speckle tracking echocardiography, the relative apical longitudinal strain (LS) index (RapLSI) [apical LS/ (basal LS + mid LS)] was significantly higher (1.09 ± 0.49 vs. 0.78 ± 0.23, P < 0.05) and the peak longitudinal strain rate (LSR) in LA was significantly lower in the 99m Tc-PYP scintigraphy-positive than scintigraphy-negative group (0.36 ± 0.14 vs. 0.55 ± 0.20 s-1 , P < 0.05). Multivariable logistic analysis revealed the peak LSR in LA and RapLSI were significantly associated with 99m Tc-PYP scintigraphy positivity. Receiver operating characteristic analysis showed that the area under the curve (AUC) of the peak LSR in LA for 99m Tc-PYP scintigraphy positivity was 0.79 and that the best cut-off value of the peak LSR in LA was 0.47 s-1 (sensitivity: 78.6% and specificity: 72.3%). The AUC of RapLSI for 99m Tc-PYP scintigraphy positivity was 0.69, and the cut-off value of RapLSI was decided as 1.00 (sensitivity: 43.8% and specificity: 87.5%) according to the previous report. The 99m Tc-PYP scintigraphy positivity in patients with RapLSI ≥ 1.0 and the peak LSR in LA ≤ 0.47 s-1 was 83.3% (5/6), and the 99m Tc-PYP scintigraphy negativity in patients with RapLSI < 1.0 and the peak LSR in LA > 0.47 s-1 was 96.6% (28/29). CONCLUSIONS: Left atrial and LV strain analysis were significantly associated with 99m Tc-PYP scintigraphy positivity in ATTR-CM patients with moderate to severe AS. The combination of the peak LSR in LA and RapLSI might be a useful predictor of the presence of ATTR-CM in patients with moderate to severe AS.

Apical longitudinal strain can help predict the development of left ventricular thrombus after anterior myocardial infarction

Abstract Background: Left ventricular (LV) thrombus formation is a common complication of anterior myocardial infarction (ANT-MI). The aim of this study was to investigate the relationship between apical longitudinal strain (ALS) and LV apical thrombus after ANT-MI. Methods: The cross-sectional study included a total of 235 patients who were followed up after primary percutaneous coronary intervention performed for ANT-MI and had a reduced LV ejection fraction (LVEF) (≤40%). Of these patients, 24 were excluded from the study, and the remaining 211 patients were included in the analysis. Patients were divided into two groups based on the presence (n = 42) or absence (n = 169) of LV thrombus detected by echocardiography. ALS was measured using speckle-tracking echocardiography. Results: Thrombus was detected in 42 of 211 patients. There was no significant difference between the groups regarding age or gender. Apical strain (AS), global longitudinal strain (GLS), apical wall thickness (AWT), and EF were significantly lower in patients with LV apical thrombus when compared to those without LV apical thrombus (AS, –5.00 ± 2.30% vs. −8.54 ± 2.48%, p < 0.001; GLS, −10.6 ± 3.54% vs. −12.1 ± 2.84%, p = 0.013; AWT, 4.71 ± 1.11 vs. 6.33 ± 1.78 mm, p < 0.001; EF, 31.40 ± 4.10% vs. 37.75 ± 3.17%, p < 0.001). On univariate and multivariate analyses, aneurysm (AA), AS, and AWT were found to be independent predictors of LV apical thrombus (AA, odds ratio [OR] 4.649, p = 0.010; AS, OR 1.749, p < 0.001; AWT, OR 0.729, p = 0.042). Conclusion: ALS is highly sensitive and specific for predicting LV thrombus after ANT-MI. An early and accurate evaluation of LV thrombus may prevent embolic complications, particularly cerebrovascular events.

Relationship between longitudinal strain and symptomatic status in aortic stenosis.

BACKGROUND: Global longitudinal strain (GLS) and basal longitudinal strain (BLS) assessed using two-dimensional speckle-tracking imaging have been proposed as subtle markers of left ventricular (LV) systolic dysfunction with potential prognostic value in patients with aortic stenosis (AS). The aim of this study was to evaluate the relationship between longitudinal strain and symptomatic status in patients with AS. METHODS: GLS and BLS were measured in 171 patients with pure, isolated, at least mild AS prospectively enrolled at two institutions. The population was divided into four groups: asymptomatic nonsevere AS (n = 55), asymptomatic severe AS with preserved LV ejection fraction (LVEF; ≥50%) (n = 37), symptomatic severe AS with preserved LVEF (n = 60), and severe AS with reduced LVEF (<50%) (n = 19). RESULTS: GLS was significantly different among the four groups (P < .0001), but the difference was due mainly to patients with reduced LVEFs. In addition, there was an important overlap among the groups, and in multivariate analysis, after adjustment for age, gender, AS severity, and LVEF, GLS was not an independent predictor of symptomatic status (P = .07). BLS was also significantly different among the four groups (P < .0001) but in contrast was independently associated with symptomatic status (P < .0001). However, as for GLS, there was an important overlap between groups and differences were close to intraobserver or interobserver variability (1.3 ± 1.1% and 2.0 ± 1.6%, respectively). CONCLUSIONS: In this prospective multicenter cohort of patients with wide ranges of AS severity, symptoms, and LVEFs, BLS but not GLS was independently associated with symptomatic status. However, there was an important overlap among groups, and differences were close to measurements' reproducibility, raising caution regarding the use of longitudinal strain, at least as a single criterion, in the decision-making process for patients with severe asymptomatic AS.