CT-derived 3D longitudinal strain showed strong agreement with TTE, but TTE-derived LV-GLS was superior to CT for detecting high-probability pulmonary hypertension (AUC 0.94 vs 0.85, p=0.013).
Observational (n=93)
Does multi-phase cardiac computed tomography (CT) angiography provide comparable multi-chamber longitudinal strain assessment to 2D transthoracic echocardiography in patients with severe aortic stenosis?
CT-derived 3D longitudinal strain shows strong agreement with TTE and is a valuable adjunct for quantifying extra-valvular remodelling associated with aortic stenosis progression to pulmonary hypertension.
Effect estimate: AUC (95% CI CT: 0.78-0.93, TTE: 0.89-0.99)
Absolute Event Rate: 0.85% vs 0.94%
p-value: p=0.013
Background Myocardial strain imaging is a robust tool for evaluating extra-valvular remodelling in aortic stenosis (AS). Multi-phase cardiac computed tomography (CT) angiography acquired for transcatheter aortic valve implantation (TAVI) planning enables a novel three-dimensional (3D), geometry-independent strain assessment beyond two-dimensional (2D) transthoracic echocardiography (TTE). This study evaluates the agreement and reproducibility of CT- and TTE-derived longitudinal strain and examines its association with pulmonary hypertension (PH) in significant AS. Methods Left ventricular global longitudinal strain (LV-GLS), left atrial global longitudinal reservoir strain (LA-LS), right ventricular global longitudinal strain (RV-GLS), and RV free-wall longitudinal strain (RV-FWLS) were determined using 2D TTE and CT-based 3D motion tracking in patients with severe AS undergoing TAVI evaluation. Patients with PH were defined using guideline-directed TTE criteria for high probability PH (H-PH: n = 43, 46.2%) and compared with those at low probability (L-PH: n = 50, 53.8%). Results Agreement between CT and TTE was strong for LV-GLS (r = 0.837), RV-GLS (r = 0.853), and RV-FWLS (r = 0.780) and moderate for LA-LS (r = 0.677) (all p 0.001). Peak longitudinal strain on both TTE and CT was significantly reduced in H-PH compared with L-PH ( p 0.001). Optimal strain cutoff values for identifying H-PH were lower on CT than on TTE (LV-GLS: −16.6% vs. −17.9%; LA-LS: 10.2% vs. 14.4%; RV-GLS: −15.3% vs. −20.1%; RV-FWLS: −18.0% vs. −21.1%). In an inter-modality comparison, it was found that TTE-derived LV-GLS was superior to CT-derived LV-GLS for detecting H-PH AUC: 0.94 [95% CI 0.89–0.99 vs. 0.85 95% CI 0.78–0.93, p = 0.013], whereas differences for LA-LS, RV-GLS, and RV-FWLS were non-significant (all p 0.05). TTE- and CT-derived strain measurements showed excellent reproducibility (ICC 0.9). Conclusion TAVI CT is a promising tool for 3D longitudinal strain assessment and a valuable adjunct to TTE for quantifying extra-valvular remodelling associated with AS progression to PH. Further studies are warranted to evaluate the prognostic value of multi-chamber CT-derived 3D strain in AS.
Androshchuk et al. (Wed,) conducted a observational in Severe aortic stenosis (n=93). Multi-phase cardiac computed tomography (CT) angiography vs. Two-dimensional (2D) transthoracic echocardiography (TTE) was evaluated on Detection of high probability pulmonary hypertension using LV-GLS (AUC, 95% CI CT: 0.78-0.93, TTE: 0.89-0.99, p=0.013). CT-derived 3D longitudinal strain showed strong agreement with TTE, but TTE-derived LV-GLS was superior to CT for detecting high-probability pulmonary hypertension (AUC 0.94 vs 0.85, p=0.013).