Asymptomatic mitral regurgitation When should you operate? Ben Bridgewater Cardiac surgeon and lead clinician, UHSM, Manchester Honorary Reader, Manchester University and Manchester Academic Health Science Centre Clinical Lead for SCTS, NICOR, UCL Chair SCTS database committee

Scope of talk Evidence base for surgery Current AHA/ACC guidelines Asymptomatic MR –Enriquez-Sarano 2005 operate if EROA> 40 mm Hg –Rosenhek 2006 Watchful waiting –Kang et al 2009 Better outcomes after early surgery

Changes in volume UK data 2001 to 2008 Approx. 26,000 AVRs –Increase in volume by 70% Approx. 13,000 mitral operations –More than doubled in volume Overall number of isolated mitral repairs –17 per million population per year – 4 fold regional variation –Gold standard of 30 per million per year –Likely to be at least a further doubling

Aetiology of Chronic MR Non Ischaemic –Degenerative – prolapse, flail leaflets –Rheumatic –Endocarditis –Dilated cardiomyopathy Ischaemic –Post MI

Impact of Severe MR Diastolic volume overload –Diastolic dilation –Normal or low end systolic volume –Large ejection fraction Insidious LV dysfunction –Further increase in diastolic volumes –Increased end systolic volume –Decrease in ejection fraction

Survival – medical treatment NYHA 1 or 2 –18 % dead at 5 years –33 % dead at 10 years NYHA 3 or 4 (even transient) –87 % dead at 5 years –i.e. 34 % per annum Ling NEJM 1996

Outcome - medical treatment By 10 years: –30% AF –63% CCF –90% dead or operated on Medical treatment is not a good option –Do not be fooled by an initial improvement

Outcomes from asymptomatic severe MR Enriquez Sarano 2005 –Estimated 5 year mortality 22% –5 year risk of combined cardiac endpoint 33%

Surgical Survival Pre Op Symptoms Tribouilloy 1999

IncidenceMortality

Survival

Surgical Survival Pre Op LVEF Enriquez-Sarano 1994

IncidenceMortality

Survival

Long Term Survival Mohty Circ 2001

Survival

Summary so far Severe mitral regurgitation is bad Symptomatic severe MR usually requires surgery Severe MR with impaired LV function usually requires surgery Mitral repair is better than replacement Patients are referred too late

What about asymptomatic MR? Intervene before adverse features develop Do not intervene unless it is necessary Avoid replacement in early stage disease

Ling et al 1997: observational study of early surgery vs conservative management -221 patients

Enriquez-Sarano 2005 Rosenhek 2006 Kang 2009

 456 patients  Asymptomatic organic MR  Quantitative echo-Doppler ●Mild: ERO <20mm 2 ●Moderate: ERO 20-39mm 2 ●Severe: ERO >40mm 2  Maximum FU 11.7 years ●Medical (49%) 2.7+/-2.9 yrs ●Medical/surgical 5.1+/-2.9 yrs N Engl J Med 2005;352: Mild (28%) Moderate (28%) Severe (44%) Age (yrs) 64+/-1465+/-1461+/-14 Male (%) MVP (%) LVSD (mm) 31+/-434+/-737+/-6 EF (%)68+/-970+/-8 ERO (mm 2 ) 11+/-531+/-564+/-21 MR vol (ml/beat) 21+/-1057+/ /- 29

Enriquez-Sarano New Eng J Med March year event rates with medical management –22% death from cardiac causes –14% heart failure –33% new atrial fibrillation

Enriquez-Sarano 2005 Independent predictors of mortality –Increasing age –Diabetes –Increasing EROA Patients with EROA>40 mmHg 5 years survival lower than expected Quantitative grading of MR powerful predictor of outcome Patients with EROA>40mmHg should promptly be considered for surgery

Operative mortality 0% 8 year survival 91% 38 patients of (132) underwent surgery

447 consecutive asymptomatic patients with severe MR1996 to 2005 Composite end point –Operative mortality –Cardiac death –Repeat mitral valve surgery –Urgent admission with heart failure Early surgery on 161 Conventional treatment 286 – ACC/AHA 1998 guidelines

Conventional group higher incidence of –Flail leaflet –>ERO –>LVESD –>LVEDD Undertook propensity matched comparison on 127 patients

No operative morality in operative group 94% repair rate –In follow up operative group –7 non cardiac deaths –No cardiac deaths Conventional group –12 cardiac deaths –5 non cardiac deaths

So – easy – operate on all patient with asymptomatic severe MR BUT!

Important factors Many patients in USA and Europe end up with mitral valve replacements for MR –EuroHeart Survey –Gammie, Circulation 2006

Important factors Many patients in USA and Europe end up with mitral valve replacements for MR –EuroHeart Survey –Gammie, Circulation 2006 Risk adjusted mortality following surgery for mitral regurgitation is lower in large centres –Gammie Circulation 2006 Chances of failed repair are higher in anterior leaflet/bileaflet disease –Suri et al, Ann thorac surg 2006

Many patients in USA and Europe end up with mitral valve replacements for MR –EuroHeart Survey –Gammie, Circulation 2006 Risk adjusted mortality following surgery for mitral regurgitation is lower in large centres –Gammie Circulation 2006

Degenerative disease Proportion Repair Annual centre average volume 48 cases NB - UNVALIDATED DATA

Summary Indications for mitral surgery are well defined for patients with degenerative valve disease in all but asymptomatic patients and those with very poor LV function Surgery in asymptomatic patients with normal LV size and function remains controversial but should be considered by experienced centres

‘We Must Do Better’ - Northrup 2005 Surgeon factor –Most surgeons do not routinely repair mitral valves –Non repair surgeons do not routinely refer to repair surgeons Cardiologist factor –Many cardiologists are indifferent whether a repair or a replacement is performed

What do we do? Cautious Asymptomatic mitral repair clinic –Cardiology led Exercise testing BNP measurement Detailed review of reparability Patient choice