Abstract: Objective To evaluate myocardial protection effect of different myocardial protective strategies for patients undergoing double valve replacement （DVR） . Methods From Jun. 2005 to Dec. 2005, 32 patients with predominant aortic valve stenosis undergoing DVR in Xinqiao Hospital were included in this study. These patients were randomly divided into four groups with 8 patients in each group： （1） antegrade perfusion group：Cold-blood cardioplegia was delivered antegradely through aortic root, and mitral valve replacement （MVR）was performed. Then cold-blood cardioplegia was delivered antegradely through left and right coronary ostia, and aortic valve replacement （AVR） was performed； （2）retrograde perfusion group：Cold-blood cardioplegia was delivered retrogradely and intermittently through coronary sinus, and DVR was performed； （3）antegrade＋retrograde perfusion group：The route of cold-blood cardioplegic infusion was antegrade during MVR procedure first and then retrograde during AVR procedure；and （4）beating heart group：Oxygenated blood from cardiopulmonary bypass machine was delivered retrogradely and continuously through coronary sinus, and DVR was performed with beating heart. Early clinical outcomes were observed. Serum cardiac troponin I （cTnI） was measured by enzyme-linked immunosorbent assay（ELISA）. Serum creatine kinase-MB （CK-MB） and myocardial lactic acid release rate were measured by Hitachi7150 Automatic Chemistry Analyzer. Myocardial mitochondria malondialdehyde （MDA） level was measured through thiobarbituric acid reagent species analysis. Results All the 32 patients survived their surgery and were discharged successfully. Myocardial lactic acid release rate at 80 min after aortic cross-clamping, serum cTnI and CK-MB on the first postoperative day, myocardial mitochondria MDA levels of beating heart group were 13.59%±6.27%,（1.17±0.25） ng/ml, （56.43±16.50） U/L and（2.18±1.23） nmol/（ng.prot）respectively, all significantly lower than those of retrograde perfusion group ［（33.49%±8.29%, （1.82±0.58 ）ng/ml, （78.31±21.27） U/L （5.07±2.35） nmol/（ng.prot），P＜0.05］ and antegrade＋retrograde perfusion group［20.87%±7.22%, （1.49±0.23） ng/ml,（66.67±19.13） U/L,（4.34±1.73） nmol/（ng.prot），P＜0.05］, but not statistically different from those of antegrade perfusion group ［18.83%±5.97%, （1.41±0.32） ng/ml, （63.21±37.52） U/L, （3.46±1.62） nmol/ （ng.prot），P＞0.05］. Conclusion All the four myocardial protective strategies are effective myocardial protection methods for DVR patients. Continuous retrograde perfusion with beating heart and intermittent antegrade perfusion can provide better myocardial protection, and therefore are preferred for DVR patients. The combination of antegrade and retrograde perfusion is easy to administer and does not negatively influence surgical procedures. Retrograde perfusion is also effective as it takes only a short time.
ObjectiveTo investigate long-term echocardiographic outcomes of patients after mitral and aortic valve replacement and their clinical significance. MethodsA total of 204 patients who underwent mitral and aortic valve replacement from January 1999 to June 2008 in West China Hospital of Sichuan University, and had been followed up with echocardiography for longer than 5 years were enrolled in this study. There were 60 male and 144 female patients with their age ranging from 15 to 74 (48.42±11.00)years. Postoperative follow-up time was 5 to 13 (6.34±2.05)years. Preoperative and follow-up echocardiographic results were compared. ResultsCompared with preoperative results, postoperative left atrial diameter (LA)and left ventricular diameter (LV)significantly decreased (P < 0.05), while right ventricular diameter (RV), left ventricular ejection fraction (LVEF)and left ventricular fractional shortening (LVFS)significantly increased (P < 0.05). Right atrial diameter (RA)did not change significantly (P > 0.05). In the patients mainly with mitral stenosis preoperatively, postoperative LA, LV, left atrial area (LAA), left atrial volume (LAV), mitral mean pressure gradient (MPGmv), velocity time integral (VTImv)and pressure half time (PHTmv)significantly decreased (P < 0.05), while mitral effective orifice area (EOAmv)and effective orifice area index (EOAImv)increased significantly (P < 0.05), but peak E velocity (Emv)did not change significantly (P > 0.05). In the patients mainly with mitral regurgitation preoperatively, postoperative LA and LV decreased significantly (P < 0.05), while LAA, LAV, MPGmv, VTImv, PHTmv, EOAmv and EOAImv did not change significantly (P > 0.05). In the patients mainly with aortic stenosis preoperatively, postoperative LV, interventricular septal thickness (IVS), left ventricular mass (LVM), left ventricular mass index (LVMI), aortic peak forward flow velocity(Vav)and mean pressure gradient (MPGav)significantly decreased (P < 0.05), while aortic effective orifice area (EOAav)and effective orifice area index (EOAIav)significantly increased (P < 0.05), but left ventricular posterior wall thickness (LVPW)did not change significantly (P > 0.05). In the patients mainly with aortic regurgitation preoperatively, postoperative LV, LVM, LVMI, EOAav and EOAIav decreased significantly (P < 0.05), while Vav and MPGav increased significantly (P < 0.05), but IVS and LVPW did not change significantly (P > 0.05). In mitral position, compared with patients with 25 mm prosthesis, Emv, MPGmv and VTImv of patients with 27 mm prosthesis were significantly smaller (P < 0.05), but there was no statistical difference in PHTmv, EOAmv or EOAImv between the 2 groups (P > 0.05). In aortic position, compared with patients with 21mm prosthesis, Vav, MPGav and VTIav of patients with 23 mm prosthesis were significantly smaller (P < 0.05), while EOAav and EOAIav were significantly larger (P < 0.05). In mitral position, 38 patients (21.3%)had moderate prothesis-patient mismatch (PPM)and 4 patients (2.3%)had severe PPM. In aortic position, 50 patients (24.5%)had moderate PPM and 43 patients (21.1%)had severe PPM. Consti-tuent ratio of long-term tricuspid regurgitation (TR)degree of patients after tricuspid valvuloplasty (TVP)significantly improved (P < 0.05), but constituent ratio of long-term TR degree of patients without TVP significantly deteriorated (P < 0.05). ConclusionsLeft ventricular function and hemodynamic outcomes in the long term are significantly better than preoperative results after double valve replacement, but they are still far from normal. PPM in aortic position is more severe than that in mitral position. Since residual or aggravated TR is very common in the long term, concomitant TVP should be considered more positively for patients undergoing surgery for left-sided valvular disease.