What is the clinical evidence from this study?

Study design: Cross-Sectional. Population: ST-elevated myocardial infarction (STEMI) (n=30). Intervention: Fast-strain encoding (fast-SENC) CMR vs. Feature tracking (FT) CMR. Primary outcome: Global circumferential strain (GCS) (MD 0.01%, 95% CI -0.92 to 0.95).

What does this research mean for the field?

While fast-strain encoding (fast-SENC) and feature tracking (FT) provide comparable global myocardial strain measurements in post-STEMI patients, fast-SENC demonstrates higher sensitivity and specificity for detecting infarcted myocardial segments. Novelty: ClaimNovelty.INCREMENTAL. Consensus alignment: ConsensusAlignment.NEUTRAL.

July 28, 2022Open Access

A head-to-head comparison of myocardial strain by fast-strain encoding and feature tracking imaging in acute myocardial infarction

Key Result

Fast-strain encoding and feature tracking CMR yielded nearly identical global circumferential strain measurements (mean difference 0.01%) in patients with acute ST-elevated myocardial infarction.

Study Design

Type

Cross-Sectional (n=30)

Multicenter

Structured PICO

Does fast-SENC provide comparable myocardial strain measurements to feature tracking and 2DEcho in post-STEMI patients?

Population

30 patients (mean age 69 years, 26.7% female) with ST-elevated myocardial infarction treated with primary percutaneous coronary intervention, evaluated with cardiac magnetic resonance and echocardiography within 2 days.

Exposure

Cardiac magnetic resonance (CMR) with fast-strain encoding (fast-SENC)

Comparator

CMR with feature tracking (FT) and 2D speckle tracking echocardiography (2DEcho)

Outcome

Head-to-head comparison of global circumferential strain (GCS) and global longitudinal strain (GLS)surrogate

Fast-SENC and feature tracking provide comparable global strain measurements in post-STEMI patients, with fast-SENC offering higher sensitivity and specificity for detecting infarcted segments.

Main Result

Mean Difference: 0.01 (95% CI -0.92–0.95)

Absolute Event Rate: -13.6% vs -13.6%

Limitations

Study limited to STEMI patients early after pPCI, results may not apply to all situations of reduced systolic LV function
Most infarcted segments had MI transmurality <25%, resulting in subtle lowering of strain
Relatively low number of participants (n=30)
Participating patients were somewhat younger and had a larger male proportion than average for STEMI patients in the catchment area
Limited to the acute phase of STEMI treatment without patient follow-up
Variation between left- and right-dominated coronary vessel anatomies may affect partition of segments

Abstract

Background: Myocardial infarction (MI) is a major cause of heart failure. Left ventricular adverse remodeling is common post-MI. Several studies have demonstrated a correlation between reduced myocardial strain and the development of adverse remodeling. Cardiac magnetic resonance (CMR) with fast-strain encoding (fast-SENC) or feature tracking (FT) enables rapid assessment of myocardial deformation. The aim of this study was to establish a head-to-head comparison of fast-SENC and FT in post-ST-elevated myocardial infarction (STEMI) patients, with clinical 2D speckle tracking echocardiography (2DEcho) as a reference. Methods: Thirty patients treated with primary percutaneous coronary intervention for STEMI were investigated. All participants underwent CMR examination with late gadolinium enhancement, cine-loop steady-state free precession, and fast-SENC imaging using a 1.5T scanner as well as a 2DEcho. Global longitudinal strain (GLS), segmental longitudinal strain (SLS), global circumferential strain (GCS), and segmental circumferential strain (SCS) were assessed along with the MI scar extent. Results: The GCS measurements from fast-SENC and FT were nearly identical: the mean difference was 0.01 (2.5)% (95% CI - 0.92 to 0.95). For GLS, fast-SENC values were higher than FT, with a mean difference of 1.8 (1.4)% (95% CI 1.31-2.35). Tests of significance for GLS did not show any differences between the MR methods and 2DEcho. Average strain in the infarct-related artery (IRA) segments compared to the remote myocardium was significantly lower for the left anterior descending artery and right coronary artery culprits but not for the left circumflex artery culprits. Fast-SENC displayed a higher area under the curve for detecting infarcted segments than FT for both SCS and SLS. Conclusion: GLS and GCS did not significantly differ between fast-SENC and FT. Both showed acceptable agreement with 2DEcho for longitudinal strain. Segments perfused by the IRA showed significantly reduced strain values compared to the remote myocardium. Fast-SENC presented a higher sensitivity and specificity for detecting infarcted segments than FT.

Bookmark

View Full Paper