# Atrial fibrillation is associated with increased in-hospitality mortality during Chimeric Antigen Receptor T-cell therapy hospitalizations: a retrospective cohort study in the United States

## TL;DR

Atrial fibrillation during CAR-T therapy is linked to higher in-hospital mortality and complications like heart failure and bleeding.

## Contribution

This study identifies atrial fibrillation as a risk factor for poor outcomes in CAR-T therapy, using a large U.S. hospital database.

## Key findings

- Patients with atrial fibrillation during CAR-T had 3.87 times higher odds of in-hospital mortality.
- Atrial fibrillation was associated with increased odds of acute heart failure (aOR: 10.2) and gastrointestinal bleeding (aOR: 5.46).
- Hospital stays were longer for patients with atrial fibrillation during CAR-T therapy.

## Abstract

Chimeric Antigen Receptor (CAR) T-cell therapy (CAR-T) has emerged as a promising treatment for specific hematological malignancies. While some studies suggest an association between CAR-T and atrial fibrillation (AF), more data are needed on the association of AF with CAR-T outcomes.

This retrospective cohort study utilized the National Inpatient Sample (NIS) 2017–2020 to explore in-hospital outcomes in cancer patients with AF while undergoing CAR-T. Comparisons were drawn between patients with and without AF during the hospitalization, assessing various parameters including mortality rates, length of hospital stay, and occurrences of acute heart failure, pulmonary edema, and gastrointestinal (GI) bleeding.

Of the 236,270 cancer-related hospitalizations, 1,030 cases (0.44%) received CAR-T. The average age of CAR-T recipients was 55.6 years ± 18.1 years, and females constituted 40.5% of the total CAR-T recipients. Of the 1030 patients receiving CAR-T, 97 (9.4%) had an associated diagnosis of AF during their hospitalization. A multivariable logistic regression analysis, adjusted for age, sex, race, comorbidity, and income, revealed that hospitalized cancer patients who underwent CAR-T therapy with AF had increased odds of in-hospital mortality (adjusted odds ratio, aOR: 3.87), acute pulmonary edema (aOR: 3.29), GI bleeding (aOR: 5.46), acute heart failure (aOR: 10.2), and extended hospital stays (Beta coefficient: 0.18) compared to hospitalizations with CAR-T but without AF. Similar results were observed in two sensitivity analyses: one limited to patients with diffuse B-cell lymphoma, and another excluding patients who had sepsis or respiratory failure while receiving CAR-T therapy.

In cancer patients receiving CAR-T, inpatient AF is independently associated with a higher risk of in-hospital mortality, acute pulmonary edema, gastrointestinal bleeding, acute heart failure, and prolonged hospitalization.

The online version contains supplementary material available at 10.1186/s40959-025-00334-5.

Hypotension and arrhythmias are common adverse cardiovascular events in hospitalized patients receiving Chimeric Antigen Receptor T-cell therapy (CAR-T).Atrial fibrillation was present in close to 10% of patients receiving CAR-T while hospitalized.Atrial fibrillation (at any time) was associated with increased in-hospital mortality, gastrointestinal bleeding, acute heart failure, pulmonary edema, and extended hospitalizations in cancer patients receiving CAR-T.

Hypotension and arrhythmias are common adverse cardiovascular events in hospitalized patients receiving Chimeric Antigen Receptor T-cell therapy (CAR-T).

Atrial fibrillation was present in close to 10% of patients receiving CAR-T while hospitalized.

Atrial fibrillation (at any time) was associated with increased in-hospital mortality, gastrointestinal bleeding, acute heart failure, pulmonary edema, and extended hospitalizations in cancer patients receiving CAR-T.

The online version contains supplementary material available at 10.1186/s40959-025-00334-5.