# A Case of Cyanamide-Ethanol Reaction Leading to Atrial Fibrillation and Heart Failure

## TL;DR

A 65-year-old man developed heart issues after drinking alcohol while on cyanamide therapy, highlighting a rare but dangerous drug-alcohol interaction.

## Contribution

First reported case of cyanamide-ethanol reaction causing atrial fibrillation and heart failure.

## Key findings

- A 65-year-old male developed atrial fibrillation and heart failure after alcohol consumption during cyanamide therapy.
- Cyanamide-ethanol reaction can lead to severe cardiovascular complications beyond previously known vasodilatory shock.
- This case emphasizes the need to consider cyanamide-ethanol reaction in diagnosing acute circulatory or respiratory failure.

## Abstract

The cyanamide-ethanol reaction (CER) is a rare but potentially life-threatening adverse event caused by the inhibition of aldehyde dehydrogenase (ADLH), leading to the accumulation of acetaldehyde after alcohol intake. This reaction is characterized by facial flushing, hypotension, tachycardia, nausea, and vomiting. We report the case of a 65-year-old male who developed new-onset atrial fibrillation (AF) and congestive heart failure (CHF) following moderate alcohol consumption while on cyanamide therapy for alcohol dependence. About twelve hours after taking cyanamide, he consumed alcohol equivalent to 32 grams of ethanol and soon experienced tachycardia, dyspnea, and nausea. Electrocardiography revealed AF, and subsequent imaging and laboratory tests confirmed the diagnosis of CHF. While vasodilatory shock related to CER has previously been documented, to our knowledge, this is the first reported case of CER-induced AF and CHF. This case underscores the necessity of including CER as a differential diagnosis in patients presenting with acute circulatory or respiratory failure while undergoing cyanamide therapy.