What is occult constrictive pericarditis?

Classical constrictive physiology on cardiac catheterisation may not be evident in certain cases of occult constriction. This typically occurs in those who have been given excessive diuretic therapy. Such cases will show normal basal hemodynamics and left ventricular systolic function. With intravenous infusion of 1 litre of normal saline over 6-8 minutes, striking elevation of filling pressure are noted. Diagnostic features would be typical pressure wave pattern of constriction, loss or reversal of respiratory variation of right atrial pressure and equalisation of diastolic intracardiac pressures. In one study, 19 patients were identified over a period of 5 years [1]. They had unexplained fatigue, dyspnea and chest pain. There was dramatic response in the 11 patients who underwent pericardiectomy. Gross and microscopic evidence of pericardial pathology was established. Cardiac catheterization with fluid challenge showed near normal response after pericardiectomy.

A recent review suggested that detailed clinical evaluation and multimodality imaging to be considered in such cases and diagnosis should not depend on fluid challenge alone. The initial report cited was nearly half a century back and investigations like computed tomography and magnetic resonance imaging which have a great role in the evaluation of constrictive pericarditis are available now [2].

References

1. Bush CA, Stang JM, Wooley CF, Kilman JW. Occult constrictive pericardial disease. Diagnosis by rapid volume expansion and correction by pericardiectomy. Circulation. 1977 Dec;56(6):924-30. doi: 10.1161/01.cir.56.6.924. PMID: 923061.
2. Al-Kazaz M, Klein AL, Oh JK, Crestanello JA, Cremer PC, Tong MZ, Koprivanac M, Fuster V, El-Hamamsy I, Adams DH, Johnston DR. Pericardial Diseases and Best Practices for Pericardiectomy: JACC State-of-the-Art Review. J Am Coll Cardiol. 2024 Aug 6;84(6):561-580. doi: 10.1016/j.jacc.2024.05.048. PMID: 39084831.