Department of Pediatrics, Division of Pediatric Cardiology, Oregon Health and Science University, Portland, OR 97239, USA.
Europace. 2010 Sep;12(9):1341-3. doi: 10.1093/europace/euq169. Epub 2010 Jun 1.
Cardiac resynchronization therapy can improve cardiac function in children with heart failure. The optimal method of assessing dyssynchrony has not been established. Newer tissue Doppler techniques such as strain assessment and speckle tracking appear to be promising for optimization of resynchronization. Two children aged 7 weeks and 4 months, with transposition of the great arteries and ventricular septal defect, and double outlet right ventricle with pulmonary stenosis, developed heart block after surgery. Conventional epicardial pacing resulted in heart failure in both. Upgrade to cardiac resynchronization therapy was not associated with normalization of function by echo, necessitating optimization. Baseline ventriculo-ventricular delay was 4 ms. Speckle tracking strain assessment was performed while adjusting ventriculo-ventricular delay. In Patient 1, synchrony was best with left ventricular (LV) activation preceding right ventricular (RV) by 30 ms. In Patient 2, it was best with RV preceding LV by 20 ms. At follow-up, both patients had normalization of function. In each case, optimization and reprogramming could be done live with no need for offline analysis. Speckle tracking strain analysis appears to be successful in the live, on-site optimization of cardiac resynchronization therapy in children. Further studies may help refine this process further.
心脏再同步治疗可改善心力衰竭儿童的心脏功能。尚未确定评估不同步的最佳方法。新型组织多普勒技术，如应变评估和斑点追踪，似乎有望优化再同步。两名分别为 7 周和 4 个月大的儿童，患有大动脉转位和室间隔缺损，以及双出口右心室伴肺动脉瓣狭窄，术后发生心脏传导阻滞。传统的心外膜起搏在两者中均导致心力衰竭。升级为心脏再同步治疗并未通过超声心动图使功能正常化，需要进行优化。基础心室-心室延迟为 4ms。在调整心室-心室延迟的同时进行斑点追踪应变评估。在患者 1 中，左心室（LV）激活比右心室（RV）提前 30ms 时同步性最佳。在患者 2 中，RV 比 LV 提前 20ms 时同步性最佳。随访时，两名患者的功能均正常化。在每种情况下，均无需离线分析即可现场进行优化和重新编程。斑点追踪应变分析似乎成功地用于儿童心脏再同步治疗的现场实时优化。进一步的研究可能有助于进一步完善这一过程。
