QTc interval and prolongation as predictors of atrial fibrillation in lung adenocarcinoma patients treated with osimertinib

Osimertinib has been established as an effective therapy for patients with lung adenocarcinoma. Several influences on heart rhythm have been discovered in recent years. However, the predictive factors for the development of atrial fibrillation (AF) have not been extensively researched. We aimed to investigate the survival and outcomes of patients with lung adenocarcinoma receiving osimertinib.

A retrospective single-center evaluation was conducted on patients with lung adenocarcinoma who were treated with osimertinib between 2016 and 2024. The primary outcome was the newly onset of atrial fibrillation following the use of osimertinib, while secondary endpoints included PR interval, QT, QTc, QTc prolongation, and ventricular rate recorded via electrocardiogram.

A total of 184 patients were enrolled for analysis. The incidence of newly developed AF was 5.43% (n=10). Patients with newly developed AF exhibited significantly longer QTc intervals after osimertinib use (472 [443–531] vs. 445.5 [384–638], p = 0.0157), a higher incidence of QTc prolongation prior to osimertinib use (37.5% vs. 6.35%, p = 0.0019) and after osimertinib use (70.0% vs. 33.98%, p = 0.0244), elevated ventricular rates after osimertinib use (132.5 [107–175] vs. 100.5 [55–154], p = 0.0002), and increased mortality (70.0% vs. 31.61%, p = 0.0125).

The incidence of newly developed AF after osimertinib use is statistically related to the QTc interval and QTc prolongation both prior to and after the treatment for lung adenocarcinoma. Various electrocardiographic parameters associated with patient outcomes in lung adenocarcinoma following osimertinib treatment can be assessed, and the development of a predictive scoring model for survival is warranted in the future.