Atrial fibrillation seriously affects the quality of life of patients, and its resultant heart failure, stroke and other thromboembolic events are the main causes of death or disability in patients. This not only affects patients’ life treatment, but also undoubtedly increases the risk of falls and fractures in the elderly population, and in more severe cases, ventricular tachycardia and ventricular fibrillation secondary to slow arrhythmias may occur after a long R-R interval, which is seriously life-threatening. Patients with atrial fibrillation with long RR intervals are commonly seen in the following two types: severe sinus arrest, sinus bradycardia or sinus block only after the termination of an episode of atrial tachyarrhythmia represented by paroxysmal atrial fibrillation, i.e., fast-slow syndrome (paroxysmal atrial fibrillation and post-atrial fibrillation recorded by ECG and/or Holter; long intervals of 2s with dizziness, blackness and/or syncope during the conversion of definite atrial fibrillation to sinus rhythm ); the other type is a long RR interval that occurs during an AF episode. Atrial fibrillation combined with a long R-R interval has a different pathogenesis. We know that atrial fibrillation is a progressive disease. Atrial fibrillation has a significant effect on sinus node function. Atrial fibrillation causes a constant rhythmic reorganization of the sinus node by ectopic excitation, which interferes with the normal release of impulses from the sinus node. In addition, prolonged atrial fibrillation causes fibrosis of the atrial muscle, which in turn affects impulse delivery and conduction in the sinoatrial node. On the other hand, atrial fibrosis with increasing age and other comorbidities (e.g., hypertension, diabetes mellitus, etc.) can itself lead to functional changes in the sinus node and atrioventricular node, impaired electrical conduction of the heart, and long R-R intervals on the ECG. For patients with different types of atrial fibrillation with long RR intervals, no clear recommendation is made in the relevant guidelines. In the case of patients with fast-slow syndrome, the presence of an underlying sinus node lesion and the need for a permanent pacemaker are more controversial. It is currently believed that for a select group of patients, who may undergo catheter ablation to eradicate atrial fibrillation and long R-R intervals, a pacemaker implantation is not required. Let’s look at a patient admitted to our center: This patient had a long RR interval associated with paroxysmal atrial fibrillation, which disappeared after successful catheter ablation to maintain sinus rhythm. Catheter ablation of atrial fibrillation to maintain sinus rhythm can reduce the effect of rapid atrial fibrillation on sinus node function, promote the recovery of sinus node function, reduce the rhythm reorganization effect on the sinus node, and reduce the occult conduction to the atrioventricular node; reduce the electrical activity of atrial disturbance and contain the further development of electrical remodeling. In addition, catheter ablation eliminates the influence of the vagus nerve, which can induce atrial fibrillation with increased vagal tone, reduces the role of the vagus node, and maintains sinus rhythm with relatively enhanced sympathetic action. The treatment of AF with long RR intervals still lacks data from large-scale studies to justify it. Whether pacing or catheter-based radiofrequency ablation should be used is still controversial. However, theoretically, for those without clear lesions in the sinus node and atrioventricular node, catheter radiofrequency ablation can be performed first, and the rhythm and heart rate can be closely followed after the procedure; for those with clear organic lesions causing abnormalities in the sinus node and atrioventricular node, pacing therapy can be considered; if economic conditions allow, radiofrequency ablation can be performed first and then pacing therapy can be performed, and the recovery time of the sinus node can be measured intraoperatively. In clinical practice, the characteristics of different patients’ conditions should be combined with the individual conditions of the patients, concomitant underlying diseases, the experience and technology of the operators, economic costs and other factors, and the patients should be allowed to participate in the formulation of treatment decisions on the basis of effective communication with the patients, so as to carry out treatments that meet the clinical treatment objectives, economic benefits and improve the quality of life.