Quantification of mitral valve regurgitation with color flow Doppler using baseline shift

3D vena contracta area after MitraClip© procedure: precise quantification of residual mitral regurgitation and identification of prognostic information

BACKGROUND

Percutaneous mitral valve repair (PMVR) is increasingly performed in patients with severe mitral regurgitation (MR). Post-procedural MR grading is challenging and an unsettled issue. We hypothesised that the direct planimetry of vena contracta area (VCA) by 3D-transoesophageal echocardiography allows quantifying post-procedural MR and implies further prognostic relevance missed by the usual ordinal scale (grade I-IV).

METHODS

Based on a single-centre PMVR registry containing 102 patients, the association of VCA reduction and patients' functional capacity measured as six-minute walk distance (6 MW) was evaluated. 3D-colour-Doppler datasets were available before, during and 4 weeks after PMVR.

RESULTS

Twenty nine patients (age 77.0 ± 5.8 years) with advanced heart failure (75.9% NYHA III/IV) and severe degenerative (34%) or functional (66%) MR were eligible. VCA was reduced in all patients by PMVR (0.99 ± 0.46 cm² vs. 0.22 ± 0.15 cm², p < 0.0001). It remained stable after median time of 33 days (p = 0.999). 6 MW improved after the procedure (257.5 ± 82.5 m vs. 295.7 ± 96.3 m, p < 0.01). Patients with a decrease in VCA less than the median VCA reduction showed a more distinct improvement in 6 MW than patients with better technical result (p < 0.05). This paradoxical finding was driven by inferior results in very large functional MR.

CONCLUSIONS

VCA improves the evaluation of small residual MR. Its post-procedural values remain stable during a short-term follow-up and imply prognostic information for the patients' physical improvement. VCA might contribute to a more substantiated estimation of treatment success in the heterogeneous functional MR group.

Value of transesophageal echocardiography (TEE) guidance in minimally invasive mitral valve surgery

The role of intraoperative transesophageal echocardiography (TEE) has increased tremendously since its first use in 1979. Today intraoperative TEE is a class I indication for surgical mitral valve reconstruction for evaluation of mitral valve pathology, graduation of mitral regurgitation and detection of potential risk factors as well as post-repair assessment. Real-time three-dimensional TEE offers anatomical visualization of the mitral valve apparatus, fundamental for virtual surgical planning of proper annuloplasty ring size. As minimally invasive and even off-pump techniques for mitral valve repair become more popular, image guidance by intraoperative TEE will play an essential role.