(P47) Obstructive Shock Caused by Morgagni Hernia

Chief Complaint : syncope

History of Present Illness : A 77-year-old female with a history of hypertension visited to the emergency room after syncope for 1 minute accompanied by transient loss of consciousness while eating. It was first episode of syncope she had ever experienced. She had intermittent chest discomfort since a year ago.

Pertinent Physical Exam: The initial vital sign in the emergency room was 91/69mmHg-73/min-20/min-35.6’c. After 1 hour, blood pressure was elevated to 118/59 without any intervention. There was no significant drop in systolic and diastolic blood pressure on 3-position blood pressure test.

Pertinent Laboratory Data: The chest x-ray showed a large fatty mass in the right cardiophrenic angle area.Laboratory test results for glucose, electrolytes, hematocrit, BNP and troponin were within the normal reference range. The initial electrocardiogram presents as normal sinus rhythm without electrical change. On the bedside transthoracic echocardiography, normal left ventricular systolic function and collapse of right atrium (RA) in the late diastole due to mass like lesion from the outside of pericardium were observed. The chest computed tomography (CT) showed Morgagni hernia containing omental fat in the right cardiophrenic angle.

Case Discussion: The patient was admission for transthoracic surgery part and underwent elective laparoscopic operation by general surgery surgeon few days later. There was 5*2cm of omental hernia above the mediastinum, that underwent reduction and was applied by mesh repair.
At one year follow-up of the patient, chest discomfort and syncope does not recur which were considered symptoms due to Morgagni hernia.

The RA is at its lowest pressure in late diastole at the onset of atrial relaxation. During this period, RA is most susceptible to collapse from increased surrounding pressure. Late diastolic RA collapse is therefore the earliest echocardiographic sign of tamponade. As with tamponades, end-diastolic RA collapse was also observed by echocardiography in this case. However, the cause is presumed to be due to the omental hernia, not the pericardial effusion. Therefore, we hypothesized that Morgagni hernia may cause a mass effect in the adjacent heart, which may induce obstructive shock.

References and Acknowledgements (Optional): not applicable