SLC9A1 and Paroxysmal atrial fibrillation: For example, atrial fibrillation and diabetes are known to be associated with a (CaMKII-dependent) increase in late INa22,23,44–46 as well as NHE1 activity.47,48 Almost 30% of our HFpEF patient cohort were diagnosed with diabetes and 15% with paroxysmal AF.