Kaneshiro Takashi, Suzuki Hitoshi, Yamada Shinya, Kamiyama Yoshiyuki, Saitoh Shu-ichi, Takeishi Yasuchika
Department of Cardiology and Hematology, Fukushima Medical University, Japan.
Int Heart J. 2012;53(4):249-52. doi: 10.1536/ihj.53.249.
Intrathoracic impedance monitoring has been reported to be useful for prediction of worsening chronic heart failure (CHF). However, it has not revealed the relation between changes in intrathoracic impedance and improvement of cardiac function in CHF patients with cardiac resynchronization therapy (CRT) implantation. Therefore, we investigated whether intrathoracic impedance change reflects reverse left ventricular (LV) remodeling in response to CRT in patients with CHF. The study subjects consisted of 29 CHF patients (23 males, mean age 64 ± 12 years) with CRT-defibrillator (CRT-D) implantation. The patients were divided into two groups based on whether the Opti-vol Fluid Index® reached over 60 ohms (group A, n = 7) or not (group B, n = 22) within 6 months of observation after CRT-D implantation. Levels of plasma B-type natriuretic peptide (BNP) were measured, and LV end-diastolic volume (LVEDV), LV end-systolic volume (LVESV), and LV ejection fraction (LVEF) were evaluated before and 6 months after CRT-D implantation. In group B, BNP (556 ± 88 pg/mL versus 330 ± 70 pg/mL, P < 0.05), LVEDV (177 ± 18 mL versus 149 ± 14 mL, P < 0.01), and LVESV (128 ± 14 mL versus 100 ± 12 mL, P < 0.01) were significantly decreased 6 months after CRT-D implantation. LVEF (28 ± 2% versus 35 ± 2%, P < 0.01) was significantly increased after CRT-D implantation. On the other hand, no significant changes were detected in any parameters in group A. These data showed intrathoracic impedance changes reflected reverse LV remodeling in response to CRT in patients with CHF. Therefore, the monitoring of changes in intrathoracic impedance is useful for predicting CRT responders in patients with CHF.
据报道，胸腔内阻抗监测有助于预测慢性心力衰竭（CHF）的病情恶化。然而，对于植入心脏再同步治疗（CRT）的CHF患者，它尚未揭示胸腔内阻抗变化与心功能改善之间的关系。因此，我们研究了胸腔内阻抗变化是否反映了CHF患者对CRT的左心室（LV）逆向重构。研究对象包括29例植入CRT除颤器（CRT-D）的CHF患者（23例男性，平均年龄64±12岁）。根据CRT-D植入后6个月观察期内Opti-vol Fluid Index®是否达到60欧姆以上，将患者分为两组（A组，n = 7；B组，n = 22）。测量血浆B型利钠肽（BNP）水平，并在CRT-D植入前和植入后6个月评估左心室舒张末期容积（LVEDV）、左心室收缩末期容积（LVESV）和左心室射血分数（LVEF）。在B组中，CRT-D植入后6个月，BNP（556±88 pg/mL对330±70 pg/mL，P < 0.05）、LVEDV（177±18 mL对149±14 mL，P < 0.01）和LVESV（128±14 mL对100±12 mL，P < 0.01）显著降低。CRT-D植入后LVEF（28±2%对35±2%，P < 0.01）显著升高。另一方面，A组的任何参数均未检测到显著变化。这些数据表明，胸腔内阻抗变化反映了CHF患者对CRT的LV逆向重构。因此，监测胸腔内阻抗变化有助于预测CHF患者对CRT的反应。
