1. Jeff Macemon MBChB, PDMSM Advanced Trainee, CTS
Two-Year Outcomes of Surgical Treatment of Moderate Ischaemic Mitral Regurgitation
Jeff Macemon
MBChB, PDMSM
Advanced Trainee, CTS

3. BACKGROUND

9. A patient who is undergoing CABG had Moderate Ischaemic Mitral Regurgitation. Should repair or replacement of the Mitral Valve be performed? No
Repair
Replacement

10. Background ~10% of patient develop Mitral Regurgitation following MI
Caused by
Papillary muscle displacement
Leaflet tethering
Reduced closing forces
Annular dilatation
MR had an adverse effect on heart failure
Available evidence for Severe MR supports surgical management at the time of CABG
Management of Moderate iMR remains controversal

11. Background Some experts advocate revascularisation alone
Others support restrictive annuloplasty
The addition of Mitral surgery at the time of CABG necessitates
Opening of the heart
Longer CPB
Leading to increased perioperative risk

12. Background Cardiothoracic Surgical Trials Network
CABG alone vs CABG + MV repair
At 1 year there was no significant difference in LV reverse remodelling or MACCE
Combined procedure significantly reduced prevalence of moderate or severe MR at the expense of higher postoperative AV arrhythmias and serious neurological events
The current study reports the 2 year outcomes for the same cohort

13. Hypothesis MV repair at time of CABG:
Positive influence on reverse ventricular remodelling
i.e. reduces LVESVI
And hence improvement on MACCE and survival

14. Patient cohort 26 centres
Adults with moderate iMR and multivessel CAD undergoing CABG
Patients with structural MR excluded
Verified by independent lab
Approved rigid or semirigid annuloplasty ring to downsize the MV annulus
CPB supported CABG

15. Trial end points Primary: Secondary endpoints
Degree of left ventricular reverse remodelling
As measured by LVESVI
Secondary endpoints
Findings on TTE
MACCE (composite of death/stroke/subsequent MV surgery/hospitalisation for heart failure/worsening NYHA class/worsening MR/worsening quality of life/re hospitalisation.

16. LV regional wall motion
Motion at each of the 17 segments was assessed at
6, 12, and 24 months

17. Results 301 patients (151 CABG vs 150 CABG/MVR)
Similar baseline characteristics
“Concomitant procedures were performed in 19%”
In CABG/MVR group average MVA 31.4+/- 5.0mm
93% patients received ring of 30mm or less

18. Results X-clamp time 8 CABG patients underwent combined procedure
74.7 +/ min vs / min (P<0.001)
8 CABG patients underwent combined procedure
3 MVR/CABG patients underwent CABG alone
2 patients in CABG alone underwent redo for MVR

19. Results At 2 years LVESVI Mod or severe MR
42.2 +/- 20.0ml vs /- 20.6ml (P=0.71)
Mod or severe MR
11.2% vs 32.3% (P<0.001)

20. Results MACCE Quality of life
No difference at 2 years
Quality of life
No difference
Combined procedure group had higher DASI (cardiac physical function) scores P=0.02

24. Conclusion
Findings imply that patient enrolled in this trial had iMR caused by reversible ischaemia rather than nonviable scar formation
Addition of MV repair to CABG had no incremental effect on LV remodelling at 2 years
Patients who underwent CABG alone had higher postop mod/severe MR but did not translate into MACCE
Addition of MVR associated with longer cross clamp and bypass times, longer post op length of stay and higher serious neurological and SVA events

25. Strengths of the study Good follow on from original design
100% patient follow up

26. Limitations of the study
Self reported
Primary end point was echo finding, not MACCE
Did not specify preop evaluation of myocardial viability
Short observation period

27. CABG or MVR/CABG??