Department of Clinical Physiology, Sahlgrenska University Hospital, Gothenburg, Sweden; Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
Department of Clinical Physiology, Sahlgrenska University Hospital, Gothenburg, Sweden; Department of Cardiology, Sahlgrenska University Hospital, Gothenburg, Sweden; Department of Radiology, Sahlgrenska University Hospital, University of Gothenburg, Gothenburg, Sweden; Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
J Am Soc Echocardiogr. 2018 Mar;31(3):304-313.e3. doi: 10.1016/j.echo.2017.11.011. Epub 2017 Dec 29.
The pulsed-wave Doppler recording in the descending aorta (PWD) is one of the parameters used in grading aortic regurgitation (AR) severity. The aim of the present study was to investigate the assessment of chronic AR by PWD with insights from cardiovascular magnetic resonance (CMR).
This prospective study comprised 40 patients investigated with echocardiography and CMR within 4 hours either prior to valve surgery (n = 23) or as part of their follow-up (n = 17) due to moderate or severe AR. End-diastolic flow velocity (EDFV) and the diastolic velocity time integral (dVTI) were measured. The appearance of diastolic forward flow (DFF) was noted. Phase-contrast flow rate curves were obtained in the DAO.
Twenty-five patients had severe and eight had moderate AR by echocardiography (seven were indeterminate). The EDFV was below the recommended threshold (>20 cm/sec) in 13 patients (52%) with severe AR. Lowering the EDFV threshold (>13 cm/sec) and with a dVTI threshold >13 cm showed negative likelihood ratios of 0.27 and 0.09, respectively. Detection of DFF with PWD identified a nonuniform velocity profile by CMR with positive and negative likelihood ratios of 7.0 and 0.19, respectively. The relation between EDFV and DAO regurgitant volume (DAO-RVol) was strong in patients without (R = 0.88) and weak in patients with DFF (R = 0.49). The DAO-RVol as a percent of the total RVol decreased with increasing ascending aorta (AAO) size and increased with increasing AR severity.
Our findings suggest that PWD provides semiquantitative parameters useful to assess chronic AR severity. The limitations are related to nonuniform velocity contour and variable degree of lower body contribution, which depends on AR severity but also on the AAO size.
降主动脉的脉冲波多普勒记录（PWD）是用于分级主动脉瓣反流（AR）严重程度的参数之一。本研究旨在通过心血管磁共振（CMR）深入了解 PWD 评估慢性 AR。
这项前瞻性研究纳入了 40 例患者，这些患者在接受瓣膜手术前 4 小时内（n=23）或因中重度 AR 进行随访时（n=17）接受了超声心动图和 CMR 检查。测量舒张末期血流速度（EDFV）和舒张速度时间积分（dVTI）。注意到存在舒张期前向血流（DFF）。在降主动脉（DAO）获得相位对比流速曲线。
25 例患者经超声心动图诊断为重度 AR，8 例为中度 AR（7 例为不确定）。13 例（52%）重度 AR 患者的 EDFV 低于推荐阈值（>20cm/s）。降低 EDFV 阈值（>13cm/s）和 dVTI 阈值>13cm 显示出的阴性似然比分别为 0.27 和 0.09。PWD 检测到 DFF 可识别出 CMR 上非均匀速度轮廓，其阳性和阴性似然比分别为 7.0 和 0.19。在没有 DFF 的患者中，EDFV 与 DAO 反流容积（DAO-RVol）之间的关系较强（R=0.88），而在有 DFF 的患者中较弱（R=0.49）。DAO-RVol 占总 RVol 的百分比随升主动脉（AAO）大小的增加而降低，随 AR 严重程度的增加而增加。
我们的研究结果表明，PWD 提供了有用的半定量参数来评估慢性 AR 严重程度。局限性与非均匀速度轮廓和下半身贡献程度有关，其程度取决于 AR 严重程度，但也取决于 AAO 大小。
