Integrated Assessment of Coronary Physiology Based on Coronary Angiography in Heart Transplant Patients

Simone Fezzi1,2, Gabriele Pesarini1, Ludovica Guerrieri1

  • 1Division of Cardiology, Department of Medicine, University of Verona, Verona, Italy.

Insights

Computational analysis of coronary flow (μFR) and microvascular resistance (AMR) from angiography improves risk assessment in heart transplant recipients. These techniques enhance early detection of cardiac allograft vasculopathy, aiding in better patient management.

Area of Science:

  • Cardiology
  • Transplant Medicine
  • Medical Imaging Analysis

Background:

  • Early detection of cardiac allograft vasculopathy (CAV) post-heart transplant (HTx) using invasive coronary angiography is difficult.
  • CAV poses a significant challenge to long-term graft survival.

Purpose of the Study:

  • To evaluate if computational techniques assessing epicardial lesions (μFR) and microvascular function (AMR) improve risk stratification in HTx patients.
  • To determine the utility of quantitative flow ratio (μFR) and angiography microvascular resistance (AMR) in predicting clinical events.

Main Methods:

  • Retrospective analysis of 86 HTx patients with <50% coronary stenosis.
  • Calculation of quantitative flow ratio (μFR) based on Murray's law for epicardial assessment.
  • Measurement of angiography microvascular resistance (AMR) for microvascular assessment.
  • Correlation of μFR and AMR with target vessel failure (TVF) and heart failure (HF) hospitalizations over 43 months.

Main Results:

  • A significant association was found between lower μFR values and TVF.
  • A μFR threshold of ≤0.93 predicted TVF with 76.0% accuracy.
  • Microvascular dysfunction (AMR ≥ 2.5) was significantly associated with increased HF hospitalizations (HR: 7.36).

Conclusions:

  • Angiography-derived computational analysis of epicardial and microvascular physiology can enhance risk stratification in heart transplant patients.
  • These non-invasive computational methods offer a promising approach for early detection and management of CAV.
Abstract