Boogers Mark M, Van Kriekinge Serge D, Henneman Maureen M, Ypenburg Claudia, Van Bommel Rutger J, Boersma Eric, Dibbets-Schneider Petra, Stokkel Marcel P, Schalij Martin J, Berman Daniel S, Germano Guido, Bax Jeroen J
Department of Cardiology, Leiden University Medical Center, Leiden, The Netherlands.
J Nucl Med. 2009 May;50(5):718-25. doi: 10.2967/jnumed.108.060657.
The significance of left ventricular (LV) dyssynchrony for the prediction of response to cardiac resynchronization therapy (CRT) has been demonstrated. Parameters reflecting LV dyssynchrony (phase SD, histogram bandwidth) can be derived from gated myocardial perfusion SPECT (GMPS) using phase analysis. The feasibility of LV dyssynchrony assessment with phase analysis on GMPS using Quantitative Gated SPECT (QGS) software has not been demonstrated in patients undergoing CRT. The aim of the present study was to validate the QGS algorithm for phase analysis on GMPS in a direct comparison with echocardiography using tissue Doppler imaging (TDI) for LV dyssynchrony assessment. Also, prediction of response to CRT using GMPS and phase analysis was evaluated.
Patients (n = 40) with severe heart failure (New York Heart Association class III-IV), an LV ejection fraction of no more than 35%, and a QRS complex greater than or equal to 120 ms were evaluated for LV dyssynchrony using GMPS and echocardiography with TDI. At baseline and after 6 mo of CRT, clinical status, LV volumes, and LV ejection fraction were evaluated. Patients with functional improvement were classified as CRT responders.
Both histogram bandwidth (r = 0.69, r(2) = 0.48, SEE = 25.4, P < 0.01) and phase SD (r = 0.65, r(2) = 0.42, SEE = 26.8, P < 0.01) derived from GMPS correlated significantly with TDI for assessment of LV dyssynchrony. At baseline, CRT responders showed a significantly larger histogram bandwidth (94 degrees +/- 23 degrees vs. 68 degrees +/- 21 degrees , P < 0.01) and a larger phase SD (26 degrees +/- 6 degrees vs. 18 degrees +/- 5 degrees , P < 0.01) than did nonresponders. Receiver-operating-characteristic curve analysis identified an optimal cutoff value of 72.5 degrees for histogram bandwidth to predict CRT response, yielding a sensitivity of 83% and a specificity of 81%. For phase SD, sensitivity and specificity similar to those for histogram bandwidth were obtained at a cutoff value of 19.6 degrees .
QGS phase analysis on GMPS correlated significantly with TDI for the assessment of LV dyssynchrony. Moreover, a high accuracy for prediction of response to CRT was obtained using either histogram bandwidth or phase SD.
左心室（LV）不同步对预测心脏再同步治疗（CRT）反应的意义已得到证实。反映LV不同步的参数（相位标准差、直方图带宽）可通过门控心肌灌注单光子发射计算机断层显像（GMPS）的相位分析得出。使用定量门控单光子发射计算机断层显像（QGS）软件对接受CRT治疗的患者进行GMPS相位分析评估LV不同步的可行性尚未得到证实。本研究的目的是通过与使用组织多普勒成像（TDI）评估LV不同步的超声心动图直接比较，验证GMPS相位分析的QGS算法。此外，还评估了使用GMPS和相位分析预测CRT反应的情况。
对40例严重心力衰竭（纽约心脏协会III-IV级）、左心室射血分数不超过35%且QRS波群大于或等于120毫秒的患者，使用GMPS和TDI超声心动图评估LV不同步情况。在基线和CRT治疗6个月后，评估临床状态、左心室容积和左心室射血分数。功能改善的患者被归类为CRT反应者。
GMPS得出的直方图带宽（r = 0.69，r² = 0.48，标准误 = 25.4，P < 0.01）和相位标准差（r = 0.65，r² = 0.42，标准误 = 26.8，P < 0.01）与TDI评估LV不同步显著相关。在基线时，CRT反应者的直方图带宽（94°±23° vs. 68°±21°，P < 0.01）和相位标准差（26°±6° vs. 18°±5°，P < 0.01）显著大于无反应者。受试者工作特征曲线分析确定直方图带宽预测CRT反应的最佳截断值为72.5°，灵敏度为83%，特异性为81%。对于相位标准差，在截断值为19.6°时获得了与直方图带宽相似的灵敏度和特异性。
GMPS的QGS相位分析与TDI评估LV不同步显著相关。此外，使用直方图带宽或相位标准差预测CRT反应具有较高的准确性。
