Patient-Prosthesis Mismatch Has No Influence on In-Hospital Mortality after Aortic Valve Replacement
Chaiwut Yottasurodom MD*, Kriengkrai Namthaisong MD*, Pramote Porapakkham MD*, Choosak Kasemsarn MD*, Taweesak Chotivatanapong MD*, Pradistchai Chaiseri MD*, Suwannee Wongdit RN**, Suwanna Yasotarin RN**
Affiliation : * Department of Cardiothoracic Surgery, Central Chest Institue of Thailand, Nonthaburi, Thailand ** Cardiopulmonary Bypass Unit, Central Chest Institue of Thailand, Nonthaburi, Thailand
Objective : To analyze the relationship between prosthetic aortic valve orifice and body surface area (Effective Orifice Area
Index, EOAI) and in-hospital mortality after aortic valve replacement.
Material and Method: A prospective study was conducted between October 2007 to September 2010, 536 patients underwent
isolated aortic valve replacement (AVR) was recorded on preoperative, operative and postoperative data. Patient Prosthesis
Mismatch (PPM) was classified by Effective Orifice Area Indexed (EOAI) by prosthetic valve area divided by body surface
area as mild or no significance if the EOAI is greater than 0.85 cm2/m2, moderate if between 0.65 cm2/m2 and 0.85 cm2/m2,
and severe if less than 0.65 cm2/m2. Statistical differences were analyzed by Chi-square and student t-test with p-value less
than 0.05 considered significant.
Results : There were 304 men, mean age was 60.98 years, mean valve orifice area 1.69 cm2, body surface area 1.60 m2, cross
clamp time 1.13 hrs., bypass time 1.67 hrs. Mechanical valves were used in 274 patients (51.2%) and Bioprosthesis were
used in 181 patients (48.8%). PPM was found in 33.7%, 6.7% was severe PPM, 27% was moderate PPM and 66.3% has no
significant PPM. Over all in-hospital mortality was 1.5%. There was no significant difference in hospital mortality between
no PPM group, moderate PPM and severe PPM group (1.4% vs. 1.4% vs. 5.4%, p-value = 0.86).
Conclusion : In a large aortic valve surgery population, moderate and severe patient prosthesis mismatch occurred in
35.6% of patients but had no influence on in-hospital mortality.
Keywords : Patient-prosthesis mismatch, Effective orifice area indexed, Aortic valve surgery
