Department of Physics and Medical Technology, VU University Medical Center, Amsterdam, the Netherlands.
J Card Fail. 2009 Oct;15(8):717-25. doi: 10.1016/j.cardfail.2009.04.007. Epub 2009 Jun 13.
Normal left ventricular (LV) torsion is caused by opposite basal and apical rotation. Opposite rotation can be lost in heart failure, but might be restored by pacing; therefore, the predictive value of the loss of opposite base-apex rotation in heart failure patients for the response to cardiac resynchronization therapy (CRT) was studied.
In 34 CRT candidates and 12 controls, basal and apical LV rotations were calculated using magnetic resonance image tagging. Loss of opposite rotation was quantified by the correlation between both rotation curves: a negative correlation indicates normal, opposite rotation and a positive correlation indicates that base and apex rotate in the same direction. In patients, LV pressure was measured invasively during biventricular stimulation. Acute response to CRT was defined by >10% increase in dP/dt(max) relative to baseline. LV volume was determined at baseline and 8 months follow-up using echocardiography. The base-apex rotation correlation (BARC) was significantly higher in acute responders (n=22) than in nonresponders (n=12) and controls (0.64+/-0.51, -0.23+/-0.67, and -0.68+/-0.22, respectively; P=.001). The sensitivity and specificity for prediction of acute response were 82% and 83%, respectively, at a cutoff value of 0.5. At follow-up, volumes could be analyzed in 18 patients. In the group with BARC >0.5, end-diastolic volume decreased by 7% (NS), end-systolic volume by 16%, and ejection fraction increased by 28% (both P=.02), whereas in the group with BARC <0.5, no significant changes were observed.
The loss of opposite base-apex rotation in patients eligible for CRT is an excellent predictor of acute response and is associated with LV reverse remodeling.
正常左心室（LV）扭转是由基底和心尖相反旋转引起的。心力衰竭时可能会失去相反的旋转，但起搏可能会恢复；因此，研究了心力衰竭患者相反基底-心尖旋转丧失对心脏再同步治疗（CRT）反应的预测价值。
在 34 名 CRT 候选者和 12 名对照者中，使用磁共振图像标记计算基底和心尖 LV 旋转。通过两个旋转曲线之间的相关性来量化相反旋转的丧失：负相关表示正常，相反的旋转，正相关表示基底和心尖以相同的方向旋转。在患者中，在双心室刺激期间通过心内压测量 LV 压力。将 CRT 的急性反应定义为与基线相比 dP/dt(max)增加>10%。使用超声心动图在基线和 8 个月随访时确定 LV 容积。急性反应者（n=22）的基底-心尖旋转相关性（BARC）明显高于无反应者（n=12）和对照组（分别为 0.64+/-0.51、-0.23+/-0.67 和-0.68+/-0.22；P=.001）。BARC 的截断值为 0.5 时，预测急性反应的敏感性和特异性分别为 82%和 83%。在随访时，可对 18 名患者进行体积分析。在 BARC >0.5 的组中，舒张末期容积减少 7%（无统计学意义），收缩末期容积减少 16%，射血分数增加 28%（均 P=.02），而在 BARC <0.5 的组中，未观察到明显变化。
适合 CRT 的患者相反基底-心尖旋转的丧失是急性反应的优秀预测指标，并与 LV 逆重构相关。
