Is it effective SGLT2 inhibitors for every AF patients?

We have read with the article “Effect of SGLT2 inhibitors on cardiovascular events in patients with atrial fibrillation: A systematic review and meta- analysis of randomized controlled trials ” by Zheng et al.1 The meta-analysis included six randomized controlled studies to evaluate the effects of Sodium-glucose cotransporter-2 inhibitors (SGLT2i) on cardiovascular (CV) events in patients with atrial fibrillation (AF): [CANVAS (Canagliflozin Cardiovascular Evaluation Study), CREDENCE (Canagliflozin and Renal Events in Diabetes with Established nephropathy Clinical Evaluation), DAPA-HF (Dapagliflozin And Prevention of Adverse outcomes in Heart Failure trial), DELIVER (Dapagliflozin Evaluation to Improve the LIVEs of Patients with PReserved ejection Fraction Heart Failure), EMPEROR-Preserved(Empagliflozin Outcome Trial in Patients with Chronic Heart Failure with preserved ejection Fraction), EMPA-REG OUTCOME (Empagliflozin Cardiovascular Outcome Event Trial in Type 2 Diabetes Mellitus Patients)]. According to meta-analysis, SGLT2i reduce the incidence of CV events, particularly hospitalization for heart failure (HF), in patients with and without AF. The meta-analysis was derived from randomized clinical trials; however, access to personal data of patients in the included studies was limited. Since the patients could not be evaluated individually, whether the patients had AF and the duration and etiology of AF could not be categorized. In addition, echocardiographic examination of the patients was not specified, and it cannot be clearly distinguished whether the patients had AF due to structural heart disease. It has been shown that the etiology of AF affects CV events,2, 3 and as a result, the approach to AF patients may change. A further concern is the lack of the rates of usage of medications that can prevent AF, such as beta-blockers, antiarrhythmic agents, angiotensin-converting enzyme inhibitors, and mineralocorticoid receptor antagonists. In this case, it cannot be clearly distinguished whether the reduction in CV events is due to SGLT2i or other than SGLT2i. The study demonstrates the effectiveness of the SGLT2 inhibitor in reducing the incidence of CV events in patients with AF according to the meta-analysis. However, in order to better categorize AF, it does not provide a detailed examination of the etiology of AF based on structural or conduction system disorders. Therefore, we believe that more comprehensive studies on etiology are needed in the future.