Beta-Blockers for the Treatment of Arrhythmias: Which Drug for Which Arrhythmia? A State-of-the-Art Narrative Review.

Beta-blockers are among the most widely prescribed drugs in the management of both supraventricular and ventricular arrhythmias, and they are frequently regarded as a homogeneous pharmacological class. They are not. The agents in current use differ substantially in beta1-receptor selectivity, lipophilicity, half-life, route of administration, intrinsic sympathomimetic activity, and ancillary properties, and arrhythmias themselves differ in mechanism, adrenergic dependence, anatomical origin, and structural substrate. This narrative review examines whether these pharmacological differences translate into clinically meaningful differences in efficacy and utility, asking not only whether a beta-blocker should be used but which one should be used. Evidence was drawn from a targeted search of PubMed, Web of Science, Scopus, Ovid, Embase, and the Cochrane Library, with priority given to randomized controlled trials, meta-analyses, large registries, and contemporary society guidelines, and was synthesized qualitatively by arrhythmia type. A class effect is apparent for many indications, particularly rate control in atrial fibrillation and atrial flutter, where metoprolol, bisoprolol, and carvedilol perform broadly similarly and the choice is driven mainly by comorbidity and tolerability. Drug-specific differences emerge in three settings. In adrenergically mediated inherited syndromes, namely catecholaminergic polymorphic ventricular tachycardia and long QT syndrome, nonselective agents and especially nadolol are clearly superior to beta1-selective agents, and the same principle appears to extend to ventricular electrical storm, in which propranolol has outperformed metoprolol in a randomized comparison. In acute care, pharmacokinetics dominate, and the ultra-short-acting agents esmolol and landiolol permit a degree of titration that longer-acting drugs cannot match. In patients with heart failure and reduced ejection fraction, carvedilol, metoprolol succinate, and bisoprolol should be preferred irrespective of arrhythmia subtype because of their established mortality benefit. Conversely, beta1-selective agents, including the highly selective agent nebivolol, improve tolerability in bronchospastic disease, although this reflects respiratory tolerability rather than any demonstrated antiarrhythmic advantage, and beta-blockers have little role in Brugada syndrome or in bradycardia-dependent acquired torsades de pointes. Beta-blockers should therefore not be treated as interchangeable. Selection should integrate arrhythmic mechanism, structural substrate, and patient characteristics, and head-to-head trials remain conspicuously scarce.