Background: Dilated cardiomyopathy (DCM) is often complicated by the appearance of functional mitral regurgitation (FMR). Although mitral ring annuloplasty (MAP) is the most widely used surgical procedure for the surgical treatment of FMR, there are still reports of patients who suffer recurrent FMR at later follow-ups. We sought to investigate the efficacy of papillary muscle approximation (PMA) combined with MAP in preventing the recurrence of FMR in high-risk patients.
Methods: One hundred patients with ischaemic (74%) or non-ischaemic (26%) DCM along with severe (4+/4+) or moderately severe (3+/4+) FMR were enrolled in this prospective, cross-sectional study. According to the interpapillary muscle distance (iPMD) and coaptation depth (CD), the patients were risk stratified as low (iPMD + CD 30 mm, n= 69) and high-risk (iPMD + CD > 30 mm, n= 31) groups. The low-risk patients underwent only MAP, whereas the high-risk patients underwent MAP plus PMA.
Results: After a mean +/- SD follow-up of 40.8 +/- 12.5 months, recurrence of 3+ to 4+ MR was observed in 8 (8.7%) and 7 (11.1%) patients in the annuloplasty group (MAP-only) and one (3.4%) patient in the combination group (MAP plus PMA) (P= 0.428). At the final follow-up, the New York Heart Association (NYHA) function class was 1.57 +/- 0.62 in the annuloplasty group and 1.45 +/- 0.57 in the combination group; there was no significant difference in NYHA function class between the first and final follow-ups (P> 0.05).
Conclusion: iPMD is a valuable index in the riskstratification of the recurrence of post-MAP MR in patients with DCM complicated by FMR.The patients treated with MAP plus PMA had more favourable outcomes and lower recurrence rates than those treated via the traditional route of MAP only.