Atypical atrial flutter: Exploring the relationship between ibrutinib chemotherapy and atrial myopathy

Key Teaching Points•The incidence of atrial arrhythmia is 5%–16% in patients taking Bruton’s tyrosine kinase inhibitors, a class of chemotherapeutic agents that is used first line for many hematological malignancies. The main risk factors for developing arrhythmia on treatment are age >65 years, hypertension, prior cardiovascular disease, and a dilated left atrium.•Animal studies have shown ibrutinib leads to off-target kinase inhibition in the myocardium. This leads to increased proinflammatory signaling and impaired cardioprotective mechanisms in the atria, culminating in pathologic remodeling that promotes triggered activity and substrate for reentrant arrhythmias.•A rate control strategy is presently recommended as the first-line treatment option for atrial arrhythmias, with a rhythm control strategy reserved for those who remain symptomatic or develop a rate-related cardiomyopathy. Our case highlights atrial flutter on ibrutinib is amenable to an ablation strategy and should be considered in appropriately selected patients. •The incidence of atrial arrhythmia is 5%–16% in patients taking Bruton’s tyrosine kinase inhibitors, a class of chemotherapeutic agents that is used first line for many hematological malignancies. The main risk factors for developing arrhythmia on treatment are age >65 years, hypertension, prior cardiovascular disease, and a dilated left atrium.•Animal studies have shown ibrutinib leads to off-target kinase inhibition in the myocardium. This leads to increased proinflammatory signaling and impaired cardioprotective mechanisms in the atria, culminating in pathologic remodeling that promotes triggered activity and substrate for reentrant arrhythmias.•A rate control strategy is presently recommended as the first-line treatment option for atrial arrhythmias, with a rhythm control strategy reserved for those who remain symptomatic or develop a rate-related cardiomyopathy. Our case highlights atrial flutter on ibrutinib is amenable to an ablation strategy and should be considered in appropriately selected patients.