Beyond Atrial Fibrillation and Heart Failure: Ibrutinib-induced Pericardial Effusion.

Ibrutinib, a Bruton's tyrosine kinase inhibitor, has transformed the management of various hematological malignancies. However, its association with cardiovascular toxicities, particularly atrial fibrillation (AF), hypertension, and heart failure (HF), has raised clinical concerns. Pericardial effusion, though rare, is an emerging complication warranting attention. We present the case of a 62-year-old male with lymphoplasmacytic lymphoma, initially treated with Bendamustine and Rituximab, which was discontinued due to significant neutropenia. Ibrutinib therapy was initiated, leading to a partial response at three months. Approximately ten months into ibrutinib treatment, the patient developed new-onset dyspnea, palpitations, and dizziness. ECG revealed AF with rapid ventricular response, and transthoracic echocardiogram (TTE) showed a reduced left ventricular ejection fraction of 40 % and a moderate pericardial effusion. Baseline assessments prior to ibrutinib had indicated normal cardiac function. Given the development of heart failure with reduced ejection fraction and pericardial effusion, ibrutinib was discontinued. The patient was initiated on guideline-directed medical therapy for heart failure. Over six months, the patient exhibited significant cardiac recovery, with normalization of ejection fraction and resolution of the pericardial effusion. While atrial fibrillation and heart failure are recognized as adverse effects of ibrutinib, pericardial effusion is less commonly reported. Given the increasing use of ibrutinib, clinicians should maintain vigilance for cardiovascular complications. Early recognition and management are crucial to mitigate morbidity and mortality associated with these adverse effects. This case highlights the importance of comprehensive cardiovascular monitoring in patients receiving ibrutinib and contributes to the growing body of literature on its cardiotoxic profile.