The main risks of chronic atrial fibrillation include reduced quality of life, heart failure, and disability due to stroke, but of course there are also risks to many physiological functions. Heart failure is often unsatisfactorily controlled and the prognosis is poor if the heart fails to revert to sinus rhythm. Since both heart failure and atrial fibrillation are more frequent, have similar etiology and are mutually causative, they can easily be present in the same patient, posing a serious health risk. This confirmed the unparalleled efficacy of catheter ablation in these patients. In 2004, our center also performed catheter ablation of atrial fibrillation in patients with heart failure in parallel with international practice, and the miraculous results have strengthened our confidence. The atrial diameters before and after ablation were 56 mm and 38 mm, the left ventricular end-diastolic diameters were 61 mm and 48 mm, and the left ventricular ejection fractions were respectively. the NYHA cardiac function class was IV and I (normal), and it was a completely normal heart. Comment: This patient had a poor prognosis and short life expectancy without restoration of sinus rhythm by catheter ablation, whereas he became a completely healthy person after restoration of sinus rhythm by catheter ablation. The figure below shows ablation of the left atrial annulus pulmonary vein, ablation of CFAE, and ablation of the tricuspid annular isthmus.