Coronary disease & ACSCohort study

Myocardial Fibroblast Activation After Acute Myocardial Infarction

J Am Coll CardiolPublished

  • Prospective observational imaging study
  • hybrid PET-CMR
  • matched controls

Authors' conclusion

Myocardial fibroblast activation peaks within a week of acute myocardial infarction and extends beyond the infarct region. It declines slowly with time, persists for years, and is associated with subsequent left ventricular remodeling.

Study context

Population
Patients with acute MI
Participants
40 / 19 / 20
Exposure
Acute MI vs chronic MI vs matched controls
  • Acute MIn = 40
  • Controln = 19reference
  • Chronic MIn = 20
Outcome
Intensity, distribution and time-course of fibroblast activation ([68Ga]FAPI-46 TBRmax; burden as % myocardial involvement)

Main finding

As reported in the abstract

[68Ga]FAPI-46 burden vs late gadolinium enhancement burden (acute MI)

27.8% ± 12.4% vs 15.2% ± 10.6%; P < 0.001

Right ventricular involvement

One-third of patients

TBRmax at 1, 2, 4 and 12 weeks

4.0 ± 1.1, 3.7 ± 1.0, 3.1 ± 0.8, and 2.7 ± 0.7; P < 0.001

TBRmax Controls vs Chronic MI vs Acute MI

1.2 ± 0.1 vs 1.7 ± 0.5 vs 4.0 ± 1.1; P < 0.001

Observational data: associations, not effects.

Further findings

Baseline [68Ga]FAPI-46 burden vs remodelling · 1 year

Correlation with lower LVEF
r = −0.606
Correlation with higher indexed LV end-diastolic volume
r = 0.572
Correlation with higher scar burden
r = 0.871
  • P < 0.001 for all

Remote myocardial [68Ga]FAPI-46 uptake

Increased remote uptake associated with LV dilatation and systolic dysfunction

Original publication

Myocardial Fibroblast Activation After Acute Myocardial Infarction. J Am Coll Cardiol. Published 8 January 2025. doi:10.1016/j.jacc.2024.10.103

Summarised from the published abstract; every number is checked against it