Background
Constrictive pericarditis (CP) results in reduced pericardial compliance, ventricular interdependence, and right heart failure. Patients with untreated CP may develop liver fibrosis and ultimately cirrhosis due to chronic venous congestion. Chronic venous congestion ± fibrosis may lead to increased liver stiffness. Magnetic Resonance Elastography (MRE) was used to evaluate whether patients with CP have increased hepatic stiffness.
Methods
Prospectively, patients with suspected CP underwent 2D transthoracic echocardiography, cardiac MRI, and liver MRE. An automated method was used to draw regions of interest (ROI) on the stiffness maps to calculate the mean liver stiffness in kilopascals (kPa). A t-test with α = 0.05 was performed between stiffness values of patients with positive and negative CP findings based on previously published echocardiography criteria.
Results
Nineteen patients met inclusion criteria with a mean ± SD age of 51 ± 16years. Nine patients (47%) had CP. Mean liver stiffness trended higher in patients with CP compared to those without CP (4.04 kPa vs. 2.46; p=0.045). Liver stiffness correlated with MRI septal bounce (p=0.04), inferior vena cava size (p=0.003), echo abnormal septal motion (p=0.04), and echo mitral inflow variation >25% (p=0.02). Only MRI septal bounce predicted CP by echocardiography (p<0.001).
Conclusion
CP was associated with increased liver stiffness. The increased stiffness is most likely secondary to chronic hepatic venous congestion and/or fibrosis. MRE may be useful for noninvasive liver stiffness assessment in CP.