Impact of Obesity on Microvascular Obstruction and Area at Risk in Patients After ST-Segment-Elevation Myocardial Infarction: A Magnetic Resonance Imaging Study

Abstract

Background

Better survival for overweight and obese patients after ST-segment elevation myocardial infarction (STEMI) has been demonstrated. The association between body mass index (BMI), microvascular obstruction (MVO), and area at risk (AAR) after STEMI was evaluated.

Methods

A prospective observational study was performed to enrolled patients undergoing primary percutaneous coronary intervention (pPCI) for STEMI and cardiac magnetic resonance was performed within 5–7 days. Patients were classified as normal weight (18.5 ≤BMI <24.0 kg/m²), overweight (24.0 ≤BMI <28.0 kg/m²), or obese (BMI ≥28 kg/m²).

Results

Among 225 patients undergoing pPCI, 67 (30.00%) were normal weight, 113 (50.22%) were overweight, and 45 (20.00%) were obese. BMI ≥28 kg/m² was significantly associated with less risk of MVO when compared with a normal BMI after multivariable adjustment (overweight: HR 0.29, 95% CI 0.13–0.68, p = 0.004). Compared with normal weight patients, obese and overweight patients tend to have larger hearts (greater left ventricular end-diastolic volume [LVEDV] and left ventricular [LV] mass). In adjusted analysis, increased BMI was significantly associated with a smaller AAR. In addition, obese patients had a smaller AAR (β = −0.252, 95% CI −20.298- −3.244, p = 0.007) and AAR, % LV mass (β = −0.331, 95% CI −0.211- −0.062, p < 0.001) than normal weight patients.

Conclusion

Obesity (BMI ≥28 kg/m²) is independently associated with lower risks of MVO and a smaller AAR, % LV mass than normal weight patients among subjects undergoing pPCI for STEMI.

Keywords:

• ST-segment elevation myocardial infarction
• STEMI
• microvascular obstruction
• MVO
• cardiac magnetic resonance
• CMR
• body mass index
• BMI
• area at risk
• AAR

Data Sharing Statement

The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request.

Ethics Approval and Consent to Participate

The study data collections were approved by the Institutional Review Board of Beijing Friendship Hospital affiliated to Capital Medical University, and written informed consent was obtained from all patients.

Consent for Publication

All authors have participated in the work and have read and approved the content, and agree to submit for consideration for publication in the journal.

Acknowledgments

We sincerely thank all staffs who have contributed to this subject.

Author Contributions

All authors made a significant contribution to the work reported, whether that is in the conception, study design, execution, acquisition of data, analysis and interpretation, or in all these areas; took part in drafting, revising or critically reviewing the article; gave final approval of the version to be published; have agreed on the journal to which the article has been submitted; and agree to be accountable for all aspects of the work.

Disclosure

The authors declare that they have no competing interests.

Additional information

Funding

This work was supported by National Key R&D Program of China (2021ZD0111004), National Natural Science Foundation of China (Grant No. 82070357), Beijing Municipal Administration of Hospitals Incubating Program (Grant No. PX2018002) and Beijing Key Clinical Subject Program.