Cardiac Sarcoidosis and a Likely Pathogenic TTN Variant in a Patient Presenting With Ventricular Tachycardia.

Rare variants in TTN are the most common monogenic cause of early-onset atrial fibrillation and dilated cardiomyopathy. Whereas cardiac sarcoidosis is very underdiagnosed, a common presentation can be ventricular arrhythmias. This report presents a patient with a likely pathogenic TTN variant and cardiac sarcoidosis. (Level of Difficulty: Intermediate.).

Antithrombotic therapy for atrial fibrillation in hereditary hemorrhagic telangiectasia.

Antithrombotic therapy reduces stroke risk in patients with atrial fibrillation but at the cost of increased bleeding risk. Patients with hereditary hemorrhagic telangiectasia (HHT) are at increased bleeding risk due to fragile mucocutaneous telangiectasias and visceral arteriovenous malformations. These patients are simultaneously at elevated thrombotic risk due to the vascular abnormalities of HHT. Managing atrial fibrillation in patients with HHT represents an understudied and challenging clinical scenario. We present a retrospective cohort study investigating antithrombotic therapy in patients with HHT and atrial fibrillation. We found that antithrombotic therapy was poorly tolerated, leading to premature dose-reduction or discontinuation of therapy in a majority of patients and in a majority of treatment episodes. Five patients undergoing left atrial appendage procedures did well despite difficulties completing the prescribed course of post-procedure antithrombotic therapy. Left atrial appendage occlusion or simultaneous administration of systemic anti-angiogenic therapy may represent alternatives but require additional study in patients with HHT.