The Primary Observation Of The Left Atrial Hemodynamics Of Mitral Stenosis Patients With Different Heart Rhythm Undergoing Mechanic Heart Valve Replacement

ObjectiveTo observe the changes of left atrial hemodynamics of mitral stenosis patients with different heart rhythm undergoing mechanic heart valve replacement and explore the inter-connection between left atrial hemodynamics and atrial fibrillation (AF).MethodsThe 38 mitral stenosis patients are divided into 2 groups depending on different heart rhythms. Group A: 23 cases with atrial fibrillation (AF), Group B: 15 cases with sinus rhythm (SR), and a Control group: 29 healthy volunteers. The ratios of gender and age are controlled within a similar range. All the patients in Groups A and B were given echocardiography examination preoperatively at 6 months and 1 year or more. Then at 1 year postoperative to get the relative measurements of left atrial hemodynamics, left heart function and the heart structure.Results1. There is no significant difference in either gender or age among Groups A,B, or C (P>0.05). 2. The comparison of LAS among Groups A, B, and C:(1) Preoperatively, the LAS of Group A, and B are all significantly higherthan those of C Group (Control Group) (P<0.01); (2) Preoperatively, the LASof Group A is significantly lower than those of Group B (PO.01); (3)Postoperative LAS of Groups A, and B are all significantly lower than thepreoperatively LAS (P<0.01); (4) There are no significant differences of theLAS of Groups A, and B between 6 months and 1 year after the operation. 3.Comparison of the LAA and LAV in Groups A, B, and C: (1)Preoperatively, LAA and LAV of Groups A, and B are all significantlyhigher than those of Group C (Control Group) (P<0.01); (2) Preoperatively,LAA and LAV of Group A are all significantly larger than Group B(PO.01); (3) Postoperative LAA and LAV of Group A are all significantlysmaller than preoperative LAA and LAV (P<0.05); (4) Postoperative LAAand LAV of Group B are not significantly smaller than preoperative LAAand LAV (P>0.05); (5) There are no significant differences of LAA and LAVof Groups A, and B between 6 months and 1 year after operation. 4.Comparison of EOA among Groups A, B, and C: (1) Preoperatively, EOAof Groups A, and B are all significantly smaller than the Group C (ControlGroup) (P<0.01); (2) Postoperative LAA and LAV of Groups A, and B are allsignificantly smaller than preoperative LAA and LAV (PO.05); (3) There areno significant differences of EOA of Groups A, and B between 6 monthsand 1 year after the operation. 5. Comparison of left atrialhemodynamic indexes among Groups A, B, and C: (1) Preoperatively, PG,mPG, PHT and VTI of Groups A, and B are all significantly higher than the Group C (Control Group) (P<0.01); (2) Preoperatively, PG and mPG of Group A are all significantly larger than Group B (PO.05); (3) Postoperative PG, mPG, PHT, VTI of Groups A, and B are all significantly lower than preoperative ones (P<0.01); (4) There are no significant differences of PG, mPG, PHT, VTI of Groups A, and B between 6 months and 1 year after the operation. 6. Through the logistic regression statistics, preoperatively the occurrence of AF is related with LAV and EOA, with LAA and PG 6 months postoperatively, and only with LAA 1 year or more than 1 year postoperatively.ConclusionThe left atrial hemodynamic is not significantly improved after the mitral valve replacement (MVR).especially the patients with AF. The left atrial stress (LAS) is still lower than the patients with SR and the left atrial volume (LAV) is still larger than the SR patients. Therefore, the changes of LAS are possibly a contribution to the occurrence of AF, and the enlarged LAV is another histological element for the occurrence and sustainability of AF.