Focus Topic: Myocardial Work
Clinical Investigations
Association Between Segmental Noninvasive Myocardial Work and Microvascular Perfusion in ST-Segment Elevation Myocardial Infarction: Implications for Left Ventricular Functional Recovery and Clinical Outcomes

https://doi.org/10.1016/j.echo.2023.04.017Get rights and content

Highlights

  • Segmental noninvasive MW can provide prognostic value in MI.

  • Segmental noninvasive MW is associated with MVP in MI.

  • Segmental MWE and MVP are associated with segmental LVR.

Background

Predicting left ventricular recovery (LVR) after acute ST-segment elevation myocardial infarction (STEMI) is of prognostic importance. This study aims to explore the prognostic implications of segmental noninvasive myocardial work (MW) and microvascular perfusion (MVP) after STEMI.

Methods

In this retrospective study, 112 patients with STEMI who underwent primary percutaneous coronary intervention and transthoracic echocardiography after percutaneous coronary intervention were enrolled. Microvascular perfusion was analyzed by myocardial contrast echocardiography, and segmental MW was analyzed by noninvasive pressure-strain loops. A total of 671 segments with abnormal function at baseline were analyzed. The degrees of MVP were observed following intermittent high-mechanical index impulses: replenishment within 4 seconds (normal MVP), replenishment >4 seconds and within 10 seconds (delayed MVP), and persistent defect (microvascular obstruction). The correlation between MW and MVP was analyzed. The correlation of the MW and MVP with LVR (normalization of wall thickening, >25%) was assessed. The prognostic value of segmental MW and MVP for cardiac events (cardiac death, admission for congestive heart failure, or recurrent myocardial infarction) was evaluated.

Results

Normal MVP was seen in 70 segments, delayed MVP in 236, and microvascular obstruction in 365. The segmental MW indices were independently correlated with MVP; 244 (36.4%) segments had segmental LVR at 3-month follow-up. Segmental MW efficiency and MVP were independently associated with segmental LVR (P < .05). The χ2 of combination of segmental MW efficiency and MVP was higher than either index alone for identifying segmental LVR (P < .001). At a median follow-up of 42.0 months, cardiac events occurred in 13 patients; all regional MW parameters, high sensitivity troponin I, regional longitudinal strain, and so on were associated with cardiac events.

Conclusions

Segmental MW indices are associated with MVP within the infarct zone following reperfused STEMI. Both are independently associated with segmental LVR, and regional MW is associated with cardiac events, providing prognostic value in STEMI patients.

Section snippets

Patient Population

A total of 138 patients admitted with an initial diagnosis of STEMI who underwent successful primary PCI at the First Affiliated Hospital of Dalian Medical University from September 2017 to December 2021 were included in this retrospective evaluation; furthermore, all culprit arteries achieved thrombolysis in myocardial infarction (TIMI) 3 flow. Within 72 hours after PCI, two-dimensional (2D) echocardiography and MCE were performed. Patients with known moderate or severe valvular heart disease,

Clinical and Echocardiography Characteristics

A total of 138 patients with STEMI who underwent primary PCI were reviewed. Twenty-six patients were excluded because of moderate or severe valvular heart disease (n = 6), primary cardiomyopathy (n = 2), congenital heart disease (n = 1), previous cardiac surgery (n = 1), previous myocardial infarction (n = 2), or poor-quality images (n = 14), which was defined as not analyzable by LS or MW (≥2 consecutive segments indistinct for MW analysis). Thus, 112 patients were included in the study. The

Discussion

This study indicated that in the contemporary era of primary successful PCI treatment of STEMI with TIMI 3 flow in the culprit vessel, segmental MVP and MW abnormalities were frequently found within 72 hours after PCI. Segments with MVO showed more impaired MW indices compared with those with normal MVP and dMVP segments. In addition, sMWI, sMWE, sMCW, and sLS were independently associated with MVP. Segments that did not recover at 3-month follow-up showed more impaired MW indices compared with

Conclusion

Segmental noninvasive MW is correlated with segmental MVP within the infarct zone following reperfused STEMI. Myocardial work efficiency and MVP are independently associated with segmental LVR. We demonstrated that all regional MW parameters are associated with cardiac events at follow-up. These noninvasive echocardiography parameters may improve the evaluation of myocardial viability and prognosis in patients with STEMI who undergo primary PCI.

Acknowledgments

We thank all those who helped us during the writing of this manuscript and members of the Department of Cardiac Ultrasound for their acquisition of data.

References (26)

Conflicts of Interest: None.

This work was supported by the Liaoning Provincial Natural Science Foundation (grant no. 2019-ZD-0629).

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