Quantification of myocardial interstitial fibrosis and extracellular volume for the detection of cardiac allograft vasculopathy

AbstractIn search of a non-invasive alternative detection of early-stage cardiac allograft vasculopathy (CAV), in this preliminary study we tested the hypothesis that interstitial fibrosis quantified with cardiac magnetic resonance (CMR) can serve as a biomarker for the detection of CAV. Late-stage CAV was detected with routine X-ray coronary angiography (XRCA), while a coronary intima-media thickness ratio (IMTR)>  1 on optical coherence tomography (OCT) was used to detect early-stage CAV. Interstitial fibrosis was quantified in the endomyocardial biopsy (EMB) and indirectly with CMR as the T1 relaxation time and extracellular volume (ECV). CMR was performed within 48  h of a single invasive procedure with XRCA, OCT, and EMB procurement in stable HTx recipients (n = 27; age 54 ± 13 years, 5.4 ± 3.7 years post-transplant). XRCA-CAV and IMTR >  1 were present in 15% and 75% of study patients, respectively. The T1 relaxation times and ECV were increased in patients with XRCA-CAV (p  = 0.03 each), while IMTR and EMB interstitial fibrosis were not significantly different (both p >  0.05). ECV (ρ =  0.46, p = 0.02) and IMTR (ρ =  0.58; p = 0.01) correlated with the histological quantity of interstitial fibrosis, while the T1 relaxation time (p  = 0.06) did not. The correlation of the IMTR with the EMB interstitial fibrosis tentatively validates the hypothesis that interstitial fibrosis may serve as an early indicator of...
Source: The International Journal of Cardiovascular Imaging - Category: Radiology Source Type: research