Pericardial effusions in pulmonary arterial hypertension: characteristics, prognosis, and role of drainage.

BACKGROUND: The presence and size of a pericardial effusion in pulmonary arterial hypertension (PAH) and its association with outcome is unclear.
METHODS: In this single-center cohort study of 577 patients with group 1 PAH seen between January 1, 1995, and December 31, 2005, all patients underwent transthoracic echocardiography and were followed for ≥ 5 years. Echocardiography-guided pericardiocentesis was performed as needed.
RESULTS: Pericardial effusions on index echocardiography occurred in 150 patients (26%); 128 patients had small and 22 had moderate-sized or larger effusions. Most of the moderate or greater effusions occurred in patients who had connective tissue disease (82%). Mean right atrial pressure was 13.4 ± 4.4 mm Hg (no effusion), 15.1 ± 4.4 mm Hg (small effusion), and 17.0 ± 4.0 mm Hg (moderate or greater effusion) (P < .0001). Median survival for patients with moderate or greater effusion, mild effusion, or no effusion was 11.3 months, 42.3 months, and 76.5 months, respectively. Four of the 22 patients with moderate or greater pericardial effusions eventually required echocardiography-guided pericardiocentesis because of clinical and echocardiographic evidence of hemodynamic impact. When drained, the effusions were large (858 ± 469 mL) and generally serous. All pericardiocenteses were performed cautiously under echocardiographic guidance by a highly experienced echocardiologist, with low immediate morbidity and mortality.
CONCLUSIONS: Pericardial effusions are relatively common but rarely of hemodynamic significance in patients with PAH. However, even modest degrees of pericardial fluid are associated with a significant increase in mortality and appear to reflect the presence of associated collagen vascular disease and high right atrial pressure.