Author + information
- Yufan Yang, MD,
- Qiming Liu, MD, PhD∗ (, )
- Shenghua Zhou, MD, PhD and
- Yichao Xiao, MD
- ↵∗Second Xiangya Hospital attached to Central South University, Cardiac Catheterization Lab and Department of Cardiology, Second Xiangya Hospital attached to Central South University, 139 Middle Renmin Road, Changsha, Hunan, 410011, P.R. China
We read with great interest the paper by Liao et al. (1), wherein they proposed the novel concept of ventricular arrhythmias originating from pulmonary sinus cusp and used reversed U curve catheter method for successful ablation. It is a new method for treating complicated and hard-to-ablate ventricular arrhythmias in the clinic. However, we have some reservations about this paper.
First, this study (1) showed that the site of pulmonary left sinus was the lowest, but the electrocardiographic characteristics (Table 2) illustrated that R wave amplitude in the leads II, III, and aVF of patients with ventricular arrhythmias originating from left pulmonary sinus were higher than those originating from right and front sinuses. Theoretically, the lower the originating site, the lower would be the R wave amplitude of the inferior lead, which was opposite in this paper.
Second, in previous reports, pulmonary artery-derived ventricular arrhythmias were believed to originate mostly from pulmonary sinus cusp. In 17% of the patients with ventricular arrhythmias, mean ventricular myocardial extensions (VME) 3.25 ± 1.3 mm long and 0.83 ± 0.71 mm thick could be observed. This was pathological anatomy basis for pulmonary artery-derived ventricular arrhythmias (2) and could also explain that most such arrhythmias originated from the pulmonary root, that is, the pulmonary sinus cusp. The study by Liao et al. (1) also demonstrated that 24 cases of pulmonary artery-derived ventricular arrhythmias originated from pulmonary sinus cusp.
Third, we believe that not all ventricular arrhythmias originating from pulmonary sinus cusp need reversed U curve catheter method for ablation. Pulmonary valve is composed of left, right, and front cusp. The right and front sinuses attach to the free lateral wall of pulmonary conus in the right ventricle, and the left one attaches to the interventricular septum (3,4). The activity of right ventricle and pulmonary free lateral wall is higher than that of interventricular septum, and the reversed U curve catheter method for ablation can increase the stability and attachment degree of ablation catheter. Therefore, for patients with ventricular arrhythmias originating from right and front pulmonary sinuses, using reversed U curve catheter method can increase the efficiency and success rate of ablation. The left pulmonary sinus attached to interventricular septum has lower activity and is easy to attach with good stability. Currently, at our institute, conventional method (nonreversed U curve catheter method) is used to successfully ablate ventricular arrhythmias originating from left pulmonary sinus cusp. Sekiguchi et al. (5) also used nonreversed U curve catheter method to ablate such arrhythmias. Left sinus is closer to coronary artery than right and front sinuses. The ablation by reversed U curve catheter method will make the tip of the catheter closely attach to the arterial wall. It makes ablation energy passing through the arterial wall stronger, which increases the risk of coronary artery damage. Therefore, how to use or whether to choose reversed U curve catheter method to perform ablation for ventricular arrhythmias originating from pulmonary sinus cusp and avoid the occurrence of complications is an important issue that needs further study.
Please note: The authors have reported that they have no relationships relevant to the contents of this paper to disclose.
- American College of Cardiology Foundation
- Liao Z.,
- Zhan X.,
- Wu S.,
- et al.
- Sekiguchi Y.,
- Aonuma K.,
- Takahashi A.,
- et al.