Patient Patient, male, 35 years old. He was admitted to the hospital with “recurrent chest tightness and palpitations for 1 month”. The patient had recurrent ventricular tachycardia with electrical resuscitation several times before admission. No previous history of hypertension, diabetes mellitus or heart attack. Physical examination: BP 130/80 mmHg, clear breath sounds in both lungs. The heart rate was 80 beats/min, in rhythm, and no murmur was detected in each valve area. The ultrasound showed that the left ventricular end-diastolic internal diameter was 57 mm, the left ventricle was enlarged, the posterior inferior wall basal segment had ventricular wall tumor formation, the left ventricular EF was 51%, and the left atrium was enlarged with mild mitral regurgitation. The coronary angiogram did not show any abnormality. MRI showed thinning of the left ventricular inferior wall and ventricular wall tumor formation. After admission, he underwent catheter radiofrequency ablation for a second episode of ventricular tachycardia. During the marker test, a new point of origin of ventricular tachycardia appeared, which was of left ventricular apical origin, and was considered to be of multiple origin and associated with ventricular wall tumor. On October 28, 2008, a ventricular wall tumor resection and radiofrequency ablation of ventricular tachycardia were performed under general anesthesia outside the body. Intraoperatively, the posterior lateral and inferior walls of the left ventricle were seen to have localized ventricular wall dysplasia, which was clearly demarcated from the normal myocardium. Intraoperative electrophysiological markers showed ectopic pacing points in the posterior lateral wall and inferior wall, which were consistent with the site of dysplastic ventricular wall. The posterior lateral and inferior walls were resected separately, leaving 1 cm of tissue for the suture margin, and radiofrequency ablation was performed at the edge of the ventricular incision, and the incision was closed with 3/0 prolene tape felt suture. No new origin of ventricular tachycardia was detected by intraoperative electrophysiological markers. The postoperative recovery was uneventful and he was discharged in 7 days. The postoperative echocardiogram showed a left ventricular end-diastolic internal diameter of 52 mm and a left ventricular EF of 52%. 24-hour ambulatory electrocardiogram did not show any ventricular prematureness. The congenital sub mitral left ventricular wall tumor is a rare heart disease, which was first reported by Abrahams (1) in 1962 and has long been thought to be seen only in black Africans, but in recent years it has been reported in other races, with few sporadic cases reported in China. The etiology of congenital inferior mitral valve left ventricular wall tumor is unknown. The posterior mitral annulus is a congenital dysplasia with a congenital weak zone in the anatomy of the posterior mitral annulus. (2) Congenital sub mitral left ventricular wall tumors can also coexist with Takayasu arteritis and tuberculous pericarditis (3, 4), and are presumed to be related to immunity and infection, the pathogens of which are currently thought to be mostly syphilis and tuberculosis. Most patients have no clinical symptoms, and the main clinical symptoms reported are mitral valve closure insufficiency, arrhythmia, thromboembolism, congestive heart failure and coronary artery compression symptoms, and a few have pericardial tamponade or death due to rupture of the tumor. (3) Tachyarrhythmia is the most common cause of sudden death, and its formation is considered to be related to the folding of the neck of the tumor. This ventricular arrhythmia is generally ineffective with antiarrhythmic drugs, and most of them require radiofrequency ablation to terminate. Surgical procedures can be performed to remove the tumor with satisfactory results of radiofrequency ablation.