Automated analysis of strain rate and strain: Feasibility and clinical implications

Background: This study evaluated 3 new automated methods, based on a combination of speckle tracking and tissue Doppler, for the analysis of strain rate (SR) and strain. Feasibility and values for peak systolic strain rate (SRs) and end-systolic strain (S-es) were assessed. Methods: Thirty patients with myocardial infarction and 30 normal subjects were examined. Customized software with automatic definition of segments was used for automated measurements. SRs and SRes were measured over each segment simultaneously and identified automatically. The study compared tissue Doppler-based SR and strain measurements without (method 1) and with segment tracking (method 2) to speckle tracking-based measurements (method 3). For tracking, speckle tracking and tissue Doppler were used in combination. Standard manual analysis was used as a reference. Results: The automated analysis (16 segments, 3 apical views) required 2 minutes; manual analysis took 11 minutes. Accuracy was compared in 56 segments (28 mid-infarcted and 28 normal) from 28 patients and was 93.9% for method 1, 93.8% for method 2, 95.8% for method 3, and 96.2% for the manual method. In the normal group, mean SRs (0.27 s(-1)) was less with method 3 than with the other methods (P < .001). Conclusions: Our findings indicate that automated analysis of SR and strain, with some manual adjustment, is feasible and quicker than manual analysis. Diagnostic accuracy was similar with all methods. SR, was lower in the speckle tracking-based method than in the Doppler-based methods.