Comparison of Diagnostic Value Between STE+LDDSE and CMR-FT for Evaluating Coronary Microvascular Obstruction in Post-PCI Patients for STEMI

Abstract

Background: Coronary microvascular obstruction (CMVO) is closely associated with poor prognosis of ST-segment elevation myocardial infarction (STEMI) patients. However, data showing the comparison between cardiac magnetic resonance feature tracking (CMR-FT) and speckle tracking echocardiography (STE) combined with low-dose dobutamine stress echocardiography (LDDSE) in evaluating CMVO was scarcely available. We aimed to explore and compare the predictive value between CMR-FT and STE+LDDSE in detecting CMVO.

Methods: Sixty-one STEMI patients were executed cardiac magnetic resonance and echocardiography within the first 5-7 days after primary percutaneous coronary intervention (PCI). The myocardial strain analysis was performed in STE, STE+LDDSE, and CMR-FT, and strain parameters included radial strain (RS), circumferential strain (CS), and longitudinal strain (LS). ROC curves were performed to predict infarcted myocardium segments with CMVO.

Results: Finally, 324 infarcted myocardium segments were analyzed, including 100 infarcted segments with CMVO and 224 segments without CMVO by the gold standard assessment of late gadolinium-enhancement cardiac magnetic resonance imaging (LGE-CMR). The results showed that CS was generally superior to RS and LS in identifying CMVO. CS in CMR-FT facilitated the detection of CMVO, with a sensitivity, specificity, and accuracy of 78.00%, 81.25%, and 80.25%, respectively. The sensitivity, specificity, and accuracy of CS in STE combined with LDDSE were better than STE alone (76.00% vs 60.00%, 79.91% vs 64.29%, and 78.70% vs 62.96%, P < 0.05). In addition, CMR-FT is not superior to STE+LDDSE for detection of CMVO (P > 0.05).

Conclusion: Low-dose dobutamine can improve the clinical value of STE for evaluating CMVO in STEMI patients. Compared with CMR-FT, STE+LDDSE might be a better choice for STEMI patients because of its safety, convenience, and low-cost.

Keywords: ST-segment elevation myocardial infarction; coronary microvascular obstruction; low-dose dobutamine; magnetic resonance feature tracking; speckle tracking echocardiography.

Figure 1

Typical CMVO appearance on LGE-CMR images (A) and measurement of myocardial longitudinal peak systolic strain using CMR-FT (B) and STE+LDDSE (C). Red arrow represents CMVO within infarcted myocardium segment (Ai: basis, Aii: middle, Aiii: apex), (Bi and Ci) represent longitudinal peak systolic strain measurements of CMR-FT and LDDSE, respectively. (Bii and Cii) represent longitudinal peak systolic strain–time curve of CMR-FT and LDDSE, respectively. (Biii and Ciii) represents bull’s eye plot of CMR-FT and LDDSE, respectively.

Figure 2

The flow chart.

Figure 3

The ROC curves of myocardial deformation parameters in evaluating CMVO. (Ai–Aiii) represent ROC curves of RS, CS, and LS in STE, respectively; (Bi–Biii) represent ROC curves of RS, CS, and LS in STE+LDDSE, respectively; (Ci–Ciii) represent ROC curves of RS, CS, and LS in CMR-FT, respectively.