Right Ventricular Strain Analysis with PET-derived Feature Tracking: Direct Comparison with Magnetic Resonance using Hybrid PET/MR

UNLABELLED: Positron emission tomography (PET) provides robust assessment of cardiac function, whereas evaluation of the right ventricle (RV) remains challenging. Myocardial strain analysis has emerged as a sensitive marker for subtle wall dysfunction. We aimed to evaluate the feasibility of RV strain quantification using a newly developed PET feature tracking technique, with magnetic resonance (MR) strain as the reference standard. RESULTS: Mean GLS and GCS were -24.1±6.9% vs. -23.4±5.6% and -16.2±5.4% vs. -16.6±4.2% for PET and CMR, respectively. Both parameters showed strong correlations between the two modalities (r=0.77 and 0.74 for GLS and GCS, respectively; p<0.0001). Bland-Altman analysis demonstrated acceptable agreement, despite the presence of significant proportional bias (GLS: bias 0.1±4.4% [limits of agreement (LOA) -8.6 to 8.8], r=0.2, and p=0.01; GCS: bias -0.7±3.6% [LOA -7.8 to 6.4], r=-0.4, and p<0.0001, respectively). CONCLUSION: PET derived RV wall strain analysis demonstrated a significant correlation with MR strain. PET feature tracking has the potential as a useful tool to detect RV wall dysfunction in routine clinical practice.