Background

The pulsed-wave Doppler recording in the descending aorta (PWD_DAO) 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_DAO with insights from cardiovascular magnetic resonance (CMR).

Methods

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.

Results

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_DAO 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_CMR) was strong in patients without (R = 0.88) and weak in patients with DFF (R = 0.49). The DAO-RVol_CMR as a percent of the total RVol_CMR decreased with increasing ascending aorta (AAO) size and increased with increasing AR severity.

Conclusions

Our findings suggest that PWD_DAO 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.

中文翻译：

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慢性主动脉瓣关闭不全患者近端降主动脉中的脉冲波多普勒记录：心血管磁共振的见解。

背景

降主动脉中的脉冲多普勒记录（PWD _DAO）是用于对主动脉瓣反流（AR）严重程度进行分级的参数之一。本研究的目的是利用心血管磁共振（CMR）的研究来研究PWD _DAO对慢性AR的评估。

方法

这项前瞻性研究包括40例在瓣膜手术前（n  = 23）或 由于中度或重度AR进行随访的患者（n = 17）在4小时内接受了超声心动图和CMR的研究。测量舒张末期流速（EDFV）和舒张末期时间积分（dVTI）。注意到舒张期前向血流（DFF）的出现。在DAO中获得了相衬流速曲线。

结果

通过超声心动图检查，有25例重症患者和8例中度AR（7例不确定）。13例严重AR患者（52％）的EDFV低于建议阈值（> 20 cm / sec）。降低EDFV阈值（> 13 cm / sec）和dVTI阈值> 13 cm分别显示负似然比为0.27和0.09。用PWD _DAO检测DFF时，通过CMR识别出的速度分布不均匀，正似然比和负似然比分别为7.0和0.19。EDFV与DAO返流量（DAO-RVol _CMR）之间的关系在无（R  = 0.88）的患者中很强，而在DFF的患者中（R  = 0.49）很弱。DAO-RVol _CMR占总RVol _CMR的百分比 随着升主动脉（AAO）大小的增加而减少，而随着AR严重程度的增加而增加。

结论

我们的发现表明，PWD _DAO提供了可用于评估慢性AR严重程度的半定量参数。局限性与不均匀的速度轮廓和下半身的贡献程度有关，这取决于AR的严重程度，也取决于AAO的大小。