Serial Extracellular Volume by Coronary Computed Tomography After Acute Myocardial Infarction With Left-Main Vasospasm

A 59-year-old man with persistent chest pain presented to the emergency department in cardiogenic shock. The electrocardiogram showed sinus rhythm with ST-segment elevation in lead aVR (Figure A). Echocardiography revealed 35% ejection fraction with anteroseptal wall asynergy. Coronary angiography showed a tight left main stenosis that was relieved by nitrate (Figure B; Supplementary Movies 1,2), leading to a diagnosis of vasospasm-induced myocardial infarction. After Impella support, the patient was discharged on day 13 with anti-vasospastic therapy of calcium channel blockers and nitrates with an eventless clinical course. Cardiac biomarkers peaked at high-sensitivity troponin I of 32,814 ng/L and creatine kinase of 7,677 U/L at 9 h after angiography.

Figure.

(A) Electrocardiogram on arrival. (B) Coronary angiography of the left and right coronary artery. (C) Extracellular volume (ECV) at 2 and 7 months after discharge. (D) Late gadolinium enhancement in cardiac magnetic resonance.

Coronary computed tomography angiography (CCTA) post-discharge showed extracellular volume (ECV) of 53% in the anterior mid-apex at 2 months, decreasing to 40% at 7 months (Figure C). Cardiac magnetic resonance (CMR) imaging at 2 months indicated subendocardial late gadolinium enhancement (LGE) volume of 205 cm³ (24.4%; Figure D). ECV is a novel marker for stratifying cardiovascular risks and CCTA-derived ECV is increasingly used due to its accessibility.¹ Patients with myocardial infarction show high ECV values.²

LGE on CMR indicates myocardial fibrosis, while increased computed tomography (CT)-derived ECV may reflect irreversible myocardial fibrosis and inflamed or edematous myocardium.

The present case first documents serial ECV changes in vasospasm-induced myocardial infarction, suggesting reversible ECV increases from ischemia may indicate an acute phase risk. These serial CT-derived ECV changes may indicate myocardial recovery from the initial ischemic injury caused by coronary spasm.

Disclosures

None.

Data Availability

No.

Supplementary Files

Supplementary Movie 1. Coronary angiogram of left coronary artery before nitroglycerin administration.

Supplementary Movie 2. Coronary angiogram of left coronary artery after nitroglycerin administration.

Please find supplementary file(s);

https://doi.org/10.1253/circrep.CR-24-0094

References

• 1.   Gil K, Mikrut K, Mazur J, Black A, Truong V, Smart S, et al. Risk stratification in patients with structurally normal hearts: Does fibrosis type matter? PLoS ONE 2023; 18: e0295519.
• 2.   Sado D, Flett A, Banypersad S, White S, Maestrini V, Quarta G, et al. Cardiovascular magnetic resonance measurement of myocardial extracellular volume in health and disease. Heart 2012; 98: 1436–1441.