# When STEMI Isn’t STEMI: Cardiac Arrest from Aortic Valve Papillary Fibroelastoma – A Case Report

## TL;DR

A rare heart tumor caused a cardiac arrest, mimicking a heart attack, but was successfully treated with surgery.

## Contribution

Highlights papillary fibroelastoma as a rare but treatable cause of cardiac arrest, emphasizing the need for advanced imaging in atypical cases.

## Key findings

- A 61-year-old woman's cardiac arrest was caused by a tumor on the aortic valve, not a heart attack.
- The tumor intermittently blocked a coronary artery and was confirmed as papillary fibroelastoma through surgery.
- Early use of advanced imaging can identify rare causes of cardiac arrest when standard tests are inconclusive.

## Abstract

Cardiac arrest remains a major global cause of mortality, with both structural and non-structural cardiac abnormalities implicated. While ischemic heart disease is a common etiology, rare conditions such as papillary fibroelastoma can also result in life-threatening events through embolization or coronary obstruction. Timely recognition and advanced cardiac imaging, particularly transesophageal echocardiography, are essential in such atypical presentations.

A 61-year-old female with a history of ischemic heart disease presented to the emergency department following an out-of-hospital cardiac arrest. Initial electrocardiogram (ECG) demonstrated anterior ST-elevation myocardial infarction, which resolved on repeat ECG, prompting reconsideration of the underlying cause. The patient achieved return of spontaneous circulation twice and eventually self-extubated. Further investigation, including cardiac imaging, revealed a mobile mass on the aortic valve intermittently obstructing the left main coronary artery. The mass was surgically resected and histologically confirmed as a papillary fibroelastoma. The patient recovered fully with no neurological or cardiac complications.

This case highlights the importance of maintaining a broad differential diagnosis in patients presenting with cardiac arrest, especially when ischemic changes are transient or unexplained. Although benign, papillary fibroelastoma can lead to sudden death due to embolization or coronary obstruction. Emergency physicians should be aware of such rare but treatable causes and consider early use of advanced cardiac imaging when standard presentations do not align with the clinical picture.