Disparity in spatial distribution of pericardial calcifications in constrictive pericarditis

BACKGROUND: Pericardial calcification is seen among patients with constrictive pericarditis (CP). However, the pattern of pericardial calcium distribution and the association with clinical outcomes and imaging data are not well described. METHODS: This was a retrospective study from 2007 to 2013 to evaluate the pattern of pericardial calcium distribution by CT in CP using a semiquantitative calcium scoring system to calculate total pericardial calcium burden and distribution. Calcium localisation was allocated to 20 regions named after the corresponding heart structure. Baseline clinical data, imaging data and clinical outcomes were collected and compared between the calcified pericardium and non-calcified pericardium groups. We assessed the effect of pericardial calcium on clinical outcomes and echocardiographic data between the two groups. RESULTS: Of the 123 consecutive patients with CP (93 male; mean age 61±13 years) between 2007 and 2013, 49 had calcified pericardium and 74 had non-calcified pericardium. Distribution of calcium on the left ventricle (LV) basal anterior, mid-anterior and apical segments in addition to right ventricle (RV) apical segment was involved in <30% of the cases with the remaining segments involved in >35% of cases. A potential protective role of RV calcium on regional myocardial mechanics was noted. CONCLUSION: Preferential distribution of calcium in CP in a partial band-like pattern (from basal anterolateral LV going inferiorly and then encircling the heart to reach the RV outflow tract) with extension into the mitral and tricuspid annuli was noted. Pericardial calcium was not significantly associated to clinical outcomes.