Khurram Irfan M, Maqbool Farhan, Berger Ronald D, Marine Joseph E, Spragg David D, Ashikaga Hiroshi, Zipunnikov Vadim, Kass David A, Calkins Hugh, Nazarian Saman, Zimmerman Stefan L
From the Departments of Cardiology (I.M.K., F.M., R.D.B., J.E.M., D.D.S., H.A., D.A.K., H.C., S.N.) and Radiology and Radiological Sciences (S.L.Z.), The Johns Hopkins University School of Medicine, Baltimore, MD; and Departments of Biostatistics (V.Z.) and Epidemiology (S.N.), Johns Hopkins University, Baltimore, MD.
Circ Arrhythm Electrophysiol. 2016 Mar;9(3). doi: 10.1161/CIRCEP.115.003163.
Atrial fibrillation (AF) is associated with significant abnormalities of left atrial (LA) systolic and diastolic function. This study describes a novel measure, LA stiffness index, that estimates LA diastolic function and its association with clinical outcomes of catheter ablation.
A total of 219 AF patients referred for ablation (59% paroxysmal, mean CHA2DS2VASc score 1.7 ± 1.4) were enrolled. Atrial pressure and volume loops were prepared from invasive pressure measures and cardiac magnetic resonance imaging volumetric data during sinus rhythm for all patients. An LA stiffness index was created, defined by the ratio of change in LA pressure to volume during passive filling of LA (ΔP/ΔV). Patients were followed prospectively. Mean LA stiffness index for AF patients was 0.6 ± 0.5 mm Hg/mL (paroxysmal AF 0.51 ± 0.4 and persistent AF 0.73 ± 0.6; P < 0.001). Linear regression analysis showed a rise in the stiffness index with age, increasing at a rate of 0.02 mm Hg/mL per year (P < 0.001). The LA stiffness index was higher in patients with previous LA ablation(s) for AF (0.51 ± 0.35 versus 0.83 ± 0.70; P < 0.001). Forty of 160 patients had recurrence after AF ablation with a mean follow-up of 10.4 ± 7.6 months. Patients with recurrence had higher stiffness index than those without recurrence (0.83 ± 0.46 versus 0.40 ± 0.22; P < 0.001).
LA stiffness index, a novel measure to assess LA diastolic function, increases with age and is higher in persistent AF and in the setting of repeat AF ablation. Greater LA stiffness index was independently associated with recurrence of AF after LA ablation.
房颤（AF）与左心房（LA）收缩和舒张功能的显著异常相关。本研究描述了一种新的测量方法，即左心房僵硬度指数，用于评估左心房舒张功能及其与导管消融临床结果的关联。
共纳入219例接受消融治疗的房颤患者（59%为阵发性，平均CHA2DS2VASc评分为1.7±1.4）。根据所有患者窦性心律期间的有创压力测量和心脏磁共振成像容积数据制备心房压力和容积环。创建了一个左心房僵硬度指数，定义为左心房被动充盈期间压力变化与容积变化的比值（ΔP/ΔV）。对患者进行前瞻性随访。房颤患者的平均左心房僵硬度指数为0.6±0.5mmHg/mL（阵发性房颤为0.51±0.4，持续性房颤为0.73±0.6；P<0.001）。线性回归分析显示，僵硬度指数随年龄增长而升高，每年升高0.02mmHg/mL（P<0.001）。既往因房颤接受过左心房消融治疗的患者左心房僵硬度指数更高（0.51±0.35对0.83±0.70；P<0.001）。160例患者中有40例在房颤消融术后复发，平均随访时间为10.4±7.6个月。复发患者的僵硬度指数高于未复发患者（0.83±0.46对0.40±0.22；P<0.001）。
左心房僵硬度指数是一种评估左心房舒张功能的新方法，随年龄增长而升高，在持续性房颤和重复房颤消融的情况下更高。更大的左心房僵硬度指数与左心房消融术后房颤复发独立相关。
