Cardiac Decompression by Pericardiectomy for Constrictive Pericarditis: Multimodality Imaging to Identify Patients at Risk for Prolonged Inotropic Support

Abstract

Background: Post-pericardiectomy right ventricular (RV) failure has been reported but it remains not well-studied. To investigate imaging parameters that could predict RV function and the outcome of patients post-pericardiectomy.

Methods: We analysed data from a total of 53 CP patients undergoing pericardiectomy. Preoperative, early and at 6 months postoperative echocardiographic (echo) imaging datasets were analysed and correlated with preoperative cardiac magnetic resonance (CMR), cardiac computed tomography scans and histology. The primary endpoint of the study was RV functional status early postoperatively and at 6 months. Secondary endpoint was the need for prolonged inotropic support.

Results: A cause of CP was identified in 26 patients (49%). Inotropic support ≥ 48 hours was required in n = 28 (53%) of patients and was correlated with lower preoperative RV areas by echo or RV volumes by CMR (p < 0.05 for all). A pericardial score based on pericardial thickness/calcification and epicardial fat thickness had good diagnostic accuracy to identify patients requiring prolonged use of inotropes (area under the curve, 0.825; 95% confidence interval, 0.674-0.976). Pericardiectomy resulted in RV decompression and impaired RV function early postoperatively (fractional area change: 40.5% ± 8.8% preoperatively vs. 31.4% ± 10.4% early postoperatively vs. 42.5% ± 10.2% at 6 months, p < 0.001).

Conclusions: We show that a smaller RV cavity size and a pericardial scoring system are associated with prolonged inotropic support in CP patients undergoing pericardiectomy. RV systolic impairment post decompression is present in most patients, but it is only transient.

Keywords: Constrictive pericarditis; Echocardiography; Magnetic resonance; Multislice computed tomography; Pericardiectomy.

Figure 1. Representative examples of cardiac computed tomography images with (A) thickened and calcified pericardium; (B) thickened but not calcified pericardium. Representative examples of CMR images showing positive (C) pericardial T2-STIR images and (D) pericardial late-gadolinium enhancement. Trans-axial slices from turbo spin echo CMR showing thick (E) compared to thin (F) epicardial fat pad (shaded in yellow).

CMR: cardiac magnetic resonance, echo: echocardiographic, T2-STIR: T2 weighted short tau inversion recovery.

Figure 2. (A) Histological findings of pericardial biopsy and (B) pericardial imaging by CT and CMR in 53 patients with constrictive pericarditis undergoing pericardiectomy. (C) Distribution of pericardial thickness by CT or CMR, and percentage of CP patients with a thickened pericardium. (D) Heatmap for the relationship between cause-specific CP and the prevalence of histological findings.

CMR: cardiac magnetic resonance, CP: constrictive pericarditis, CT: computed tomography, CTD: connective tissue disorder, LGE: late gadolinium enhancement, TB: tubercolosis.

Figure 3. (A) A pericardial score based on pericardial calcification/thickness and epicardial fat thickness could be used to assess the difficulty of surgical pericardial dissection and to predict the risk for heart failure and prolonged inotropic support postoperatively. (B) Prognostic accuracy of pericardial score to identify patients at risk for prolonged inotropic support (n = 28).

AUC:= area under the curve, CT: computed tomography, RV: right ventricular.

Figure 4. RV cavity size and function preoperatively, postoperatively and at 6 months. Data are shown for changes in (A) RVEDD, (B) RVEDA, (C) RVESA, (D) FAC and (E) TAPSE.

FAC: fractional area change, RV: right ventricular, RVEDA: right ventricular end-diastolic area, RVEDD: right ventricular end-diastolic diameter, RVESA: right ventricular end-systolic area, TAPSE: tricuspid annular plane systolic excursion. ^*p < 0.05; ^†p < 0.001; ^‡p < 0.0001 vs. baseline.