To drain, or not to drain: Diagnostic and therapeutic challenges associated with cardiac tamponade in Right heart sided heart failure and pulmonary hypertension

ABSTRACT

Background: In clinical practice, cardiac tamponade is not an all-or-none phenomenon, but rather a continuum of hemodynamic impairment. Diagnosis depends on an overall assessment of clinical and echocardiographic findings, hemodynamic measurements, and other corresponding patient-level variables must be considered to make a diagnosis to initiate timely intervention.1 The identification of cardiac tamponade in the presence of severe pulmonary hypertension and right ventricular failure can be even more challenging, because the classic findings are often not observed. Our patient clearly had hemodynamic compromise (orthostatic collapses and then persistent hypotension from a large pericardial effusion but did not exhibit the common features of tamponade on ECHO. This can be explained by the preexisting, markedly elevated right-sided pressures, which prevented typical findings of pulsus paradoxus, right atrial and ventricular diastolic collapse, and equalization of diastolic pressures.1 Case presentation 44 Years old lady background of Interstitial lung disease, pulmonary artery hypertension, Right heart failure and anti-synthetase syndrome. Recently required Intensive care admission for COVID pneumonitis and was discharged on home oxygen. Now admitted to hospital after she boarded the flight without oxygen and became unwell. She was treated on lines of exacerbation of interstitial lung disease, Right heart failure and moderate pericardial effusion without signs of tamponade in ECHO and was given adequate diuresis and responded very well to it. Her oxygen requirement came down and she clinically improved. Few days after, she developed diarrhea and prerenal Acute kidney injury while in ward and became borderline hypotensive which improved after her diuretic doses were reduced and then held. She then after few days started to develop orthostatic collapses with hypotension and then became persistently hypotensive. Her CT Pulmonary angiogram showed unchanged moderate circumferential pericardial effusion, and no Pulmonary embolism. She was reviewed by Critical care outreach team and an urgent bedside Echocardiogram was performed to rule out features of tamponade which showed moderate pericardial effusion, severely dilated Right heart with massive Right ventricular pressures compressing her Left ventricle. She was urgently reviewed by cardiology and was taken to Intensive care unit for invasive hemodynamic monitoring, where she was given inotropes and inhaled pulmonary artery vasodilators. The decision was taken to cautiously diurese and not to drain the pericardial effusion due to risk of developing further instability by increasing right ventricular expansion causing further collapse and pressure on Left ventricle. Discussion and conclusion: Our case stresses on the importance of Bedside Echocardiogram in timely identifying the atypical features of cardiac tamponade and to understand the different hemodynamics and mechanism of obstructive shock in patients with pre-existing right sided heart failure. After the establishing that patient was in obstructive cardiogenic shock with atypical findings of tamponade, the next most important step was to decide whether to drain the pericardial effusion or not. In our literature search, we found that the drainage of a large pericardial effusion in patients with pulmonary hypertension has been accompanied by catastrophic, sudden hemodynamic collapse and it has been postulated that the presence of pericardial fluid limits right ventricular distension in response to pressure and volume overload. When the pericardial fluid is removed, rapid enlargement of the right ventricle causes (1) reduced right ventricular systolic function due to muscle fiber distension;and (2) compression of the left ventricle, which leads to impaired diastolic filling and left ventricular outflow track obstruction.1.