1. Khalid Swenia MBBCH FRCSC Cardiac Surgeon TMC Libyan Cardiac Society Valve working group day Sept. 21 /2010 2. Long term survival 5 year survival Normal LV function: 96% Overall 80% @ 5 years 60% @ 10 years Depressed LV function: 63% Valve related morbidity responsible for >50% late deaths Bioprosthetic valve - Reoperation: 25% @ 10 years 65% @ 15 years 3. Risk Factors for Survival after AVR Advanced age Functional status (NHYA class) Depressed LV function (aortic incompetence) Coronary artery disease Presence of endocarditis Aneurysm of ascending aorta Mismatch of prosthesis and body size 4. Risk Factors for Survival after AVR Advanced age Functional status (NHYA class) Depressed LV function (aortic incompetence) Coronary artery disease Presence of endocarditis Aneurysm of ascending aorta Mismatch of prosthesis and body size 5. The important Question ?? Labelled Area ?? The effective Orifice Area EOA 6. Comparison of EOAs for commonly implanted prosthetic valves. EOA 7. Manufacturers Numbers Valve sizes may be indicated according to: the labelled valve size the external diameter, including the sewing ring the external diameter, without the sewing ring the internal diameter the in vitro effective orifice area* the in vivo effective orifice area* (* = measured by doppler US) 8. Some Observations Valve sizing Stented valves: label size = diameter of stent without sewing ring! Stentless valve: label size = outer diameter of the graft b/c stentless valves do not have sewing rings, labelled size may more closely approximate size of valve which may be implanted However, stentless valves in vitro measurements EOAgrossly overestimate in vivo 9. The Question of EOA The problem is that there is no clear direction in terms of a best approach for the small aortic root Stentless? Bioprosthetic? (Edwards pericardial or mitroflow) Mechanical? Homograft? Aortic root enlargement? 10. Patient prosthesis mismatch *Defines aortic patient-prosthesis mismatch as arising when the valve area of the inserted prosthesis is less than that of the native valve *HOWEVER, the actual clinical definition takes into account the patients BSA, and is defined as and EOA Index < 0.85 0.9 cm2/m2 Because EOAI < 0.9 in a native aortic valve is considered to be moderate AS 11. Also, EOAI (in vivo) < 0.85cm2 is associated with a rapid rise in gradient with exercise (steep portion of performance curve) 12. EOAI vs Gradient There is a relationship between EOAI and trans- valvular gradient: EOAI > 0.85: gradient ~ 15mmHg EOAI 0.65 0.85: gradient ~ 22mmHg EOAI < 0.65: gradient ~ 33mmHg There are further increases in gradient with exercise! 13. EOAI vs LV mass regression There may be a relationship between EOAI and LV mass regression over time At 3 years (from Dusmesnil, et al) EOAI > 0.8: mean 23% reduction in LV mass EOAI < 0.8: mean 5% reduction in LV mass However, other studies (Jin, et al) show that factors other than EOAI are important determinants of LV mass regression: Gender, functional status, sinus rhythm, hypertension 14. The question remains: what is the clinical significance of LV mass regression? One abstract of 2500 pts (by Rao and WREJ showed 75 vs 84% 12-year survival for an EOAI of < 0.75 vs > 0.75, respectively) In non-aortic stenosis/AVR patients, LVM index is correlated to risk of sudden death, CHF, and long- term cardiac mortality. 15. Effect of Patient-Prosthesis Mismatch on 30-Day Mortality Blais, et al Circulation 2003 16. Patient-Prosthesis Mismatch: St Jude Bileaflet Valves Milano, Ann Thorac Surg 2002 17. Choosing the Appropriate Valve 18. Because the gradient is affected strongly by the level of activity (C.O.), it is important (valid) to take into account the patients likelihood of exercising post-operatively ie. A small prosthesis with a certain amount of patient-prosthesis mismatch is probably acceptable in a frail elderly patient 19. Cohen, et al Only randomized trial of stented vs stentless. 99 patients only! 53 CE pericardial vs 46 SJM Toronto SPV Measurements: Annular diameters with calipers Annular size using CE and SJM valve sizers Exclusions (b/c SJM Toronto valve C/Is) Heavy calcification of root STJ larger than annulus 20. RESULTS No difference in operative death (4% each) Bypass/XC times significantly longer for SPV SPV label size significantly larger than CE 26.3mm vs 22.9mm, p=0.0001 Measured annular dimension not different! 22.3mm vs 21.9mm No difference in EOAI (< 0.85cm2/m2) 14% SPV vs 11% CE EOA increased to same degree in both groups over time 21. RESULTS (cont) Peak and mean transvalvular gradients were no different between groups at 3 and 12 months 12 14mmHg, and ~6mmHg LVMI regressed significantly in both groups and to a similar degree (ie. No difference) This was the primary end-point! Note: Although maximum external diam of CE sig larger than SPV, supra-annular position of CE valve accomodates for the difference! 22. Root Enlargement Procedures 23. Manougian Procedure Nicks Procedure Konno Procedure 24. Konno Procedure 25. Conclusion 26. Patient Prosthesis Mismatch Goal is indexed AVA 0.9 cm2/m2 Indexed AVA 0.6 m2/m2 unacceptable Carefully consider valve type/size to be implanted