Atrial fibrillation （AF） as a most frequent arrhythmia has a high incidence of 79% in patients with mitral valve disease. Thrombosis, embolization and serious arrhythmia can be caused by AF. There is the recrudescent tendency in using drugs to recover the sinus rhythm, surgery and radio frequency ablation can only cure a part of patients. By now the pathogenesis of AF is not known clearly. The pathogenesis of AF from virulence gene, cardiac electrophysiology, connecxins, cell ultramicrostructure and cell signaling system are reviewed in this article.
The patients with mechanical prosthetic valve replacement need anticoagulant therapy for all their life. The incidence of thromboembolism and anticoagulation-related bleeding events still account for major postoperative complications after mechanical heart valve replacement. Most of the complications happen in the first half year after operation. Therefore, early anticoagulation therapy is very important. Of course, so far most guidelines focus stating their opinions on long-term anticoagulant therapy. However, there is no consensus about anticoagulant therapy in the early period of postoperation. In this review, we summarize early anticoagulant therapy of the patients with mechanical heart valve replacement through consulting domestic and abroad relevant research in recent years and give an overview of the present situations of early anticoagulant therapy.
Objective To report the preliminary results of intraoperative saline-irrigated radiofrequency modified maze procedure for chronic atrial fibrillation (AF) in mitral valve diseases. Methods From May 2003 to April 2004 forty-one patients underwent intraoperative saline-irrigated modified maze procedure. The patients included 13 male and 28 female. Their age ranged from 27-65 years (46±10 years). The duration of AF varied from 5 months to 15 years (4.5±3.6 years).The left atrial diameter varied from 37-93 mm (54±11mm). There were mitral stenosis 20, mitral regurgitation 1 and mitral stenosis with regurgitation 20 cases. Cardiopulmonary bypass (CPB) was established as usual. Ablation lines were made with Cardioblate (Medtronic, 25-30 W, 180-240ml/h). Having finished right-sided maze procedure, the aorta was cross-clamped and cold crystalloid or blood cardioplegia were used for myocardial protection. Left atrial incision was performed through the interatrial groove. The ablation lines were created to encircle the orifices of the left and right pulmonary veins respectively. The ablation lines were also performed from the left encircling line to the posterior mitral valvular annulus and to the orifice of left atrial appendage respectively. A ablation line was used to connect left and right pulmonary veins circumferential line. Concomitant procedures were performed (there were double valve replacement 10 cases, mitral valve replacement 31 cases, tricuspid annuloplasty 6 cases, removing the left atrial thrombi 6 cases). Results CPB time varied from 71-160 min (105±24 min) and cross-clamping time varied from 32-106 min (62±20 min). The ablation time varied from 4-22 min (11±4 min). One patient died during hospitalization and the death was caused by acute mechanic valve obstruction. During follow-up at discharge and 3 months 35% patients (14/40) were free of AF and the others were not. But at 6 months 67% patients (10/15) were free of AF. Conclusion The intraoperative saline-irrigated radiofrequency modified maze procedure is comparatively simpler and its efficacy is satisfactory.
Objective To investigate the correlation between the left atrial hydrodynamic change and atrial fibrillation (AF) in the patients with rheumatic mitral stenosis. Methods According to cardiac rhythm before operation, 49 patients with rheumatic mitral stenosis accompanying chronic AF were divided into two groups,group A: AF, 25 cases; group B: sinus rhythm, 24 cases. Control group : 29 healthy volunteers were examined. By using echocardiography, left atrial hydrodynamics were tested, and repeated 6-8 months after the operation. Results Left atrial stress (LAS), left atriala area (LAA) and left atrial volume(LAV) in group A after operation was much lower than before operation, LAS after operation in group B was also lower than before operation(Plt;0.01). Before operation, LAS in group A was significantly lower than that in group B, LAA and LAVwere larger. After operation, LAA and LAV in group A were significantly larger than those in group B(Plt;0.01). LAS, LAA and LAV in group A and group B before and after operation were higher than those in control group. Conclusion Left atrial hydrodynamic enviroment in patients with mitral stenosis has not reached normal even after valve replacement, LAS may be an important factor of causing AF.
The main purpose of this study is to observe and analyze the characteristics and the clinical significance of long-term echocardiogram data in patients after mechanical aortic valve replacement operation. Fifty-five cases were recruited over 5 years after mechanical aortic valve replacement operation, with complete echocardiogram examination profiles. The 55 subjects were divided into predominate aortic stenosis group and predominate aortic regurgitation group, based on preoperative examinations. And another way of division was also carried out that according to the effective orifice area index (EOAI), the subjects were divided into three groups, i.e., severe prosthesis-patient mismatch (PPM) group, moderate PPM group, and non PPM group. Characteristics of long-term echocardiogram data of the subjects were analyzed. Patients with aortic stenosis showed significantly decreased thickness of intraventricular septum and left ventricular posterior wall about half a year after operation (P<0.05). Half a year after operation, patients with aortic regurgitation showed decreased left ventricular internal dimension diastole and left ventricular internal dimension systole, and increased ejection fraction (P<0.05). Differences in mean aortic valve pressure gradient, forward blood flow across the aortic valves, and ejection fraction were not significant among those with severe PPM, moderate PPM, and non PPM groups (P>0.05). Number of cases of ascending aorta dimension increased as time goes on and pathogenesis of other valve diseases. A conclusion could be drawn that the heart function of patients with aortic valve disease could be improved after mechanical aortic valve replacement operation, but pathologies in other valves and ascending aorta might be increased, and therefore periodical postoperative echocardiogram evaluation with long tem pharmaceutical therapy could be necessary.