Atrial fibrillation is one of the most common arrhythmia. Cardiac mapping technology, an important method to study the electrophysiological mechanism of atrial fibrillation, can determine the abnormal origin and record the distribution and transmission way of these atrial electrical signals. This technology offers a new way for research the electrophysiological mechanism of atrial fibrillation. The purpose of this study is to review the research progress of cardiac mapping in the electrophysiological mechanism of atrial fibrillation and clinical application.
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.
Objective To explore the impact of the women taking warfarin throughout pregnancy after mechanical valve replacement on the children’s physical and mental development.Methods A total of 12 children whose mothers had taken mechanical valve replacement before pregnancy were enrolled in the experimental group in this study, for determination of their physical and mental development. The following indicators were measured: a) Physical development indexes: height, weight, sitting height, head circumference, chest circumference; b) Mental development indexes: intelligence quotient (IQ), and development quotient (DQ) which included adaptability, big movement, fine motor, language, and individual-society. According to the 1?∶?2 matching ratio, 24 children of the healthy women were selected in the control group, and then the difference of each index between the two groups was analyzed. Results In the aspects of both physical development indexes and mental development indexes, there were no significant differences in the children aged 0 to 3 yrs, 4 to 6 yrs, and 6 to 12 yrs in the two groups (Pgt;0.05). Conclusion After mechanical valve replacement, women taking oral anticoagulant warfarin in daily dose not exceeding 5mg are safe, and there are no negative effects on children’s physical and mental development.
Objective To investigate long-term echocardiography characteristics and their clinical significance of patients after mitral valve replacement （MVR）. Methods We retrospectively analyzed clinical data of 204 patients who underwent prosthetic MVR and finished echocardiography examination at least 5 years after surgery in West China Hospital of Sichuan University. There were 44 male patients and 160 female patients with their age of 23 to 73 （50.9±10.6）years. Postoperatively， all the patients were followed up for 5-15 （7.9±2.3）years and regularly received echocardiography examination at the outpatient department. Analysis variables included left atrium （LA） dimension， left ventricle （LV） dimension，right atrium （RA） dimension， right ventricle （RV） dimension， left ventricular ejection fraction （LVEF） and effective orificearea （EOA） of the mitral valve. Results Long-term echocardiography showed that LA and LV dimensions were signifi-cantly smaller than preoperative dimensions （P＜0.05）， while RA and RV dimensions were not statistically different from preoperative dimensions （P＞0.05）. Long-term LVEF was significantly higher than preoperative value （P＜0.05）. Long-term EOA was 1.1-4.8 （2.3±0.5）cm2， including EOA of 1.1-1.4 cm2 in 7 patients （3.4%，7/204），and 1.6-1.9 cm2in 42 patients （20.6%，42/204）. During long-term follow-up， 7 patients underwent their second heart surgery， including2 patients with prosthetic valve dysfunction， 1 patient with prosthetic perivalvular leak and severe hemolytic anemia，3 patients with severe tricuspid regurgitation which were not improved after medication treatment， and 1 patient with moderateaortic valve stenosis and regurgitation. Two patients had left atrial thrombosis during follow-up， including 1 patient who died of endocarditis 7 years after surgery， and another patient who was still receiving conservative therapy and further follow-up. Conclusion Concomitant tricuspid or aortic valve disease should be actively treated during MVR， and postoperative patients need better follow-up. Many patients after MVR need long-term cardiovascular medication treatment during follow-up in order to improve their heart function and long-term survival rate.
ObjectiveTo evaluate the reasonableness of anticoagulation management strategy in patients after mechanical heart valve replacement. MethodsAll patients were followed and registered continually at outpatient clinic from July 2011 to February 2013, with a minimum of 6 months after surgery. Targeted international normalized rate (INR) 1.60 to 2.20 and warfarin weekly dosage adjustment were used as the strategy of anticoagulation management. Except bleeding, thrombogenesis and thromboembolism, time in therapeutic range (TTR) and fraction of TTR (FTTR) were adopted to evaluate the quality of anticoagulation management. ResultsA total 1 442 patients and 6 461 INR values were included for data analysis. The patients had a mean age of 48.2±10.6 years (14-80 years) and the following up time were 6 to 180 months (39.2±37.4 months) after surgery. Of these patients, 1 043 (72.3%) was female and 399 (27.7%) was male. INR values varied from 0.90-8.39 (1.85±0.49) and required weekly doses of warfarin were 2.50-61.25 (20.89±6.93 mg). TTR of target INR and acceptable INR were 51.1% (156 640.5 days/306 415.0 days), 64.9% (198 856.0 days/306 415.0 days), respectively. FTTR of target INR and acceptable INR were 49.4% (3 193 times/6 461 times), 62.6% (4 047 times/6 461 times). There were 8 major bleeding events, 7 mild bleeding events, 2 thromboembolism events, and 2 thrombogenesis in the left atrium. ConclusionIt is reasonable to use target INR 1.60-2.20 and warfarin weekly dosage adjustment for patients after mechanical heart valve replacement.