ObjectiveTo evaluate myocardial segmental motion function in left ventricular of patients with rheumatic mitral stenosis by using the technology of real-time three-dimensional echocardiography (RT-3DE). MethodsWe retrospectively analyzed the clinical data of 14 patients with rheumatic mitral stenosis between October and November 2014 in our hospital as a trial group. There were 4 males and 10 females with a mean age of 50.9±9.0 years ranging from 34 to 64 years. We chose 11 healthy individuals as a control group. There were 7 males and 4 females with a mean age of 49.5±9.7 years ranging from 32 to 67 years. Both the two groups were subjected to myocardial performance evaluation using two-dimensional echocardiography (2DE) and real-time three-dimensional echocardiography (RT-3DE) to examine the left ventricular ejection fraction (LVEF), left ventricular end-diastolic volume (LVEDV), left ventricular end systolic volume (LVESV), longitudinal strain, circumferential strain, area strain, and lateral strain of each left ventricular myocardial segments. Result RT-3DE detected that the trial group had significantly lower values of LVEF, LVEDV and LVESV than those of the control group (P < 0.05). RT-3DE also revealed that the trial group had a significantly weaker longitudinal strain than the control group (P < 0.05). ConclusionRT-3DE is an accurate technology for assessing myocardial motion and function in patients with rheumatic mitral valve disease.
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.
Abstract： Objectives To determine the atrial expression of the collagen Ⅰ, collagen Ⅲ and the transforming growth factorbeta 1 (TGF-β1) in patients with rheumatic heart disease (RHD) and permanent atrial fibrillation(PAF) and to investigate the relationship between the extent of atrial fibrosis and the effectiveness of radiofrequency maze procedure in patients with RHD and PAF. Methods A total of 40 patients with RHD and PAF (≥6 months) who underwent a radiofrequency maze procedure with concomitant valvular surgery were collected for the experimental group. We acquired 100 mg of the left auricle tissue in each patient and followed up these patients after 3, 6 months of [CM(158mm]surgery. Then we assigned these patients to nonAF group and persistent AF group according to the results of the 6month followup. Another 10 patients with RHD and sinus rhythm(SR) who underwent valvular surgery alone were assigned to SR group and their left auricle tissue was also obtained. In order to determine the extent of atrial fibrosis, we observed the amount of collagen volume fraction Ⅰ，Ⅲ(CVF-Ⅰ,CVF-Ⅲ) by semiquantitative analysis with picrosirius red staining method. Using the β actin protein as the endogenous reference gene, we detected the expressions of TGF-β1 mRNA by semiquantitative reverse transcriptionpolymerase chain reaction(RT-PCR) technique. Results Each group has the same clinical baseline. At 6month follow-up, 28 among the 40 patients were categorized into the nonAF group and 12 into the AF group. (1) Patients in the nonAF group and the AF group had higher mRNA expressions of TGF-β1, CVF-Ⅰ and CVF-Ⅰ/CVF-Ⅲ compared with the SR group (F=6.487, P=0.003; F=3.711, P=0.032; F=3.697, P=0.032). The AF group had higher mRNA expressions of TGF-β1, CVF-Ⅰ and CVF-Ⅰ/CVF-Ⅲ than the nonAF group (t=4.372, P=0.043; t=4.603, P=0.038; t=4.776, P=0.035). But the CVFⅢ had no significant differences among the three groups (P＞0.05). (2) The patients whose left atrial function recovered after Maze procedure had lower mRNA expression than those patients whose left atrial function did not recover in the nonAF group (t=5.570, P=0.027). (3) The TGF-β1 mRNA expression has a positive correlation with both the contents of CVF-Ⅰ and left atrial diameter (r=0.786, Plt;0.05; r=0.858, Plt;0.05). Multiple logistic regression analysis revealed that the mRNA expression levels of TGF-β1, CVF-Ⅰ and left atrial diameter were independently associated with the postoperative persistence of atrial fibrillation. Conclusion The extent of atrial fibrosis in patients with RHD and PAF may be related to the sinus rhythm restoration and maintenance after AF surgical radiofrequency ablation and the resumption of atrial function.
Objective To evaluate the value of preoperative B-type natriuretic peptide （BNP） level in predicting new onset atrial fibrillation （AF） in patients after coronary artery bypass grafting （CABG）. Methods We electronically searched PubMed，EMbase，Cochrane library，CNKI and VIP databases from the establishment of those databases to November 2012. Evaluation standard of diagnostic tests was used to identify and screen literatures which investigated correlations between preoperative BNP levels and new onset AF of patients after CABG. Quality Assessment of Diagnostic Accuracy Studies （QUADAS） was used to evaluate study quality of included literatures. RevMan 5.0 was used for heterogeneity test. Meta-Disc 1.4 software was used for meta-analysis. Included studies were weighted and then combined. Sensitivity，specificity，diag- nostic odds ratio （DOR），positive likelihood ratio，negative likelihood ratio and corresponding 95% confidence interval（95% CI）were calculated. Summary receiver operating characteristic （SROC） curve was drawn，and the area under the SROC curve （AUC） was analyzed. Results A total of 236 studies were identi?ed，and 5 studies met the eligibility criteria including 802 patients for analysis. There were 228 patients with postoperative new onset AF，and 574 patients without postoperative AF. The quality of the included literature was relatively high. DOR of preoperative elevated BNP level with postoperative new onset AF was 4.15 with 95% CI 2.90 to 5.95. Pooled sensitivity was 0.78 with 95% CI 0.72 to 0.83，pooled specificity was 0.58 with 95% CI 0.54 to 0.58，pooled positive likelihood ratio was 1.91 with 95% CI 1.42 to 1.56，pooled negative likelihood ratio was 0.42 with 95% CI 0.32 to 0.54，and the AUC of SROC was 0.79 （Q=0.72）. Conclusion Preoperative elevated BNP level is significantly correlated with new onset AF after CABG，is a powerful predictor of postoperative AF，and can be used to predict new onset AF after CABG to a certain extent of reliability.
Objective To evaluate the therapeutic effectiveness and safety of ibutilide versus amiodarone in the treatment of atrial fibrillation and atrial flutter. Methods An electronic search in databases including PubMed, Embase, CNKI, WanFang Data, VIP Database, and The Cochrane Library (Issue 2, 2011), published from January 1994 to January 2011,was conducted to include both English and Chinese randomized controlled trials (RCTs) about ibutilide versus amiodarone in treating atrial fibrillation and atrial flutter. Two reviewers independently screened the studies according to the inclusive and exclusive criteria, extracted the data, assessed the methodological quality, and then performed Meta-analysis by using RevMan 5.0 software. Results Eight RCTs involving 506 patients were finally included. The results of Meta-analysis showed: a) The total effective rate of alleviating atrial fibrillation and atrial flutter in the ibutilide group was superior to that of the amiodarone group (OR=2.27, 95%CI 1.19 to 4.33, P=0.01); b) Four RCTs showed that ibutilide was similar to amiodarone for alleviating atrial fibrillation (OR=1.61, 95%CI 0.96 to 2.71, P=0.07), but the former was superior to the latter for alleviating atrial flutter (OR=8.97, 95%CI 4.51 to 17.84, Plt;0.000 01); c) Five RCTs showed that ibulitide took shorter time to alleviate atrial fibrillation and atrial flutter compared with amiodarone (WMD= –126.55 min, 95%CI –202.35 to –50.76, P=0.001); d) Four RCTs showed that the total adverse effect rates in the two groups had no significant difference (OR=1.13, 95%CI 0.37 to 3.43, P=0.83), but there were more cardiovascular side-effects in the ibutilide group (OR=2.36, 95%CI 1.40 to 4.01, P=0.001). Conclusion Compared with amiodarone, ibutilide has a higher total effective rate in cardioversion of atrial fibrillation and atrial flutter, and it obviously takes shorter time to alleviate atrial fibrillation and atrial flutter, but there is no significant difference in the cardioversion rate of atrial fibrillation between them. There is no significant difference in total side-effect rates between the two groups, but the cardiovascular adverse reaction in the ibutilide group is significantly higher than that of the amiodarone group. Because of the limited quantity and quality of the included studies, this conclusion has to be further proved by more high-quality RCTs.
Objective To analyze the risk factors of atrial fibrillation (AF) after radical esophagectomy, providing the basis for prevention and treatment of AF after radical esophagectomy. Methods We conducted a retrospective analysis of 335 patients' clinical data, who accepted laparoscopic combined thoracic or open radical esophagectomy in the same treatment group at Department of Thoracic Surgery of Shengjing Hospital of China Medical University between January 2014 and August 2016. There were 262 males and 73 females at age of 65.1 (43-78) years. Results There were 48 of 335 patients with AF within 1 week after surgery. By univariate analysis: age, gender, history of peripheral vascular disease and cardiac stents or angina pectoris, preoperative brain natriuretic peptide (BNP), preoperative left ventricular diastolic dysfunction, operation pattern, intraoperative blood transfusion and lymph nodes and pericardial adhesion were possible risk factors. By multivariate analysis: age, gender, history of cardiac stents or angina pectoris, preoperative BNP, operation pattern, intraoperative blood transfusion and lymph nodes and pericardial adhesion were risk factors. Conclusion The risk factors of AF after radical esophagectomy are age, gender, history of cardiac stents or angina pectoris, preoperative BNP, operation pattern, intraoperative blood transfusion and lymph nodes and pericardial adhesion. Perioperative positive intervention to above factors may reduce the incidence of postoperative AF.
Atrial fibrillation (AF) is a common arrhythmia, which can lead to thrombosis and increase the risk of a stroke or even death. In order to meet the need for a low false-negative rate (FNR) of the screening test in clinical application, a convolutional neural network with a low false-negative rate (LFNR-CNN) was proposed. Regularization coefficients were added to the cross-entropy loss function which could make the cost of positive and negative samples different, and the penalty for false negatives could be increased during network training. The inter-patient clinical database of 21 077 patients (CD-21077) collected from the large general hospital was used to verify the effectiveness of the proposed method. For the convolutional neural network (CNN) with the same structure, the improved loss function could reduce the FNR from 2.22% to 0.97% compared with the traditional cross-entropy loss function. The selected regularization coefficient could increase the sensitivity (SE) from 97.78% to 98.35%, and the accuracy (ACC) was 96.62%, which was an increase from 96.49%. The proposed algorithm can reduce the FNR without losing ACC, and reduce the possibility of missed diagnosis to avoid missing the best treatment period. Meanwhile, it provides a universal loss function for the clinical auxiliary diagnosis of other diseases.
Objective Through analyzing BKCa channel expression in atrial fibroblasts in patients with sinus rhythm and atrial fibrillation (AF), to explore the mechanism of myocardial fibrosis and provide new therapeutic strategies for the treatment and reversal of AF structure reconstruction. Methods We selected 10 patients of rheumatic heart valvular disease who underwent valve replacement surgery. They were 5 patients with sinus rhythm (a sinus rhythm group, 2 males and 3 females with an average age of 49.1±8.3 years) and 5 with AF (an AF group, 3 males and 2 females with an average age of 50.3±5.8 years). About 100 mg tissue was obtained from the right auricula dextra, and the atrial fibroblasts were cultured by tissue block adherence method, and the expression of BKCa channel genes and proteins in cultured fibroblasts was detected by quantitative real-time polymerase chain reaction (qRT-PCR) and western blotting methods. Results (1) The general data of 10 patients between the AF group and the sinus rhythm group were compared. There was no significant difference between the two groups in age (t=1.21, P=0.67) and sex (t=2.56, P=0.75). There was statistical difference in the left atrial diameter and the right atrium diameter between the two groups (t=19.45, P=0.01; t=23.52, P=0.06); (2) the mRNA expression of BKCa subunit was detected by qRT-PCR method, and there was no significant difference in the mRNA expression of BKCa α and BKCa β1 between the two groups (t=3.14, P=0.79; t=2.88, P=0.69); (3) the expression of BKCa protein was detected by western blotting method, and there was no significant difference in the protein expression of BKCa α and BKCa β1 between the two groups (t=0.55, P=0.31; t=0.73, P=0.46). Conclusion BKCa pathway may not be involved in the pathogenesis and maintenance of AF, but it may play an important role in the process of myocardial fibrosis.
Predicting the termination of paroxysmal atrial fibrillation (AF) may provide a signal to decide whether there is a need to intervene the AF timely. We proposed a novel RdR RR intervals scatter plot in our study. The abscissa of the RdR scatter plot was set to RR intervals and the ordinate was set as the difference between successive RR intervals. The RdR scatter plot includes information of RR intervals and difference between successive RR intervals, which captures more heart rate variability (HRV) information. By RdR scatter plot analysis of one minute RR intervals for 50 segments with non-terminating AF and immediately terminating AF, it was found that the points in RdR scatter plot of non-terminating AF were more decentralized than the ones of immediately terminating AF. By dividing the RdR scatter plot into uniform grids and counting the number of non-empty grids, non-terminating AF and immediately terminating AF segments were differentiated. By utilizing 49 RR intervals, for 20 segments of learning set, 17 segments were correctly detected, and for 30 segments of test set, 20 segments were detected. While utilizing 66 RR intervals, for 18 segments of learning set, 16 segments were correctly detected, and for 28 segments of test set, 20 segments were detected. The results demonstrated that during the last one minute before the termination of paroxysmal AF, the variance of the RR intervals and the difference of the neighboring two RR intervals became smaller. The termination of paroxysmal AF could be successfully predicted by utilizing the RdR scatter plot, while the predicting accuracy should be further improved.
Objective To explore the effect of aortic root perfusion of amiodarone when intractable ventricular fibrillation occurs during valve replacement. Methods Totally 42 patients were selected as a drug group, who underwent intractable ventricular fibrillation following ascending aortic opening in valve replacement in Beijing Anzhen Hospital from October 2006 to October 2016. There were 26 males and 16 females with an average age of 56.31±12.56 years. The aorta was re-blocked when intractable ventricular fibrillation occured, amiodarone (150 mg diluted to 20 ml) through the aortic root perfusion tube was applicated, and suction was repeated 8-10 times with the cumulative amount of 150-200 ml, and then the ascending aorta was opened and fast compressed with a frequency of 200 times/min. While 53 patients with the same condition during the same period were selected as a control group. There were 35 males and 18 females with an average age of 58.79±19.81 years. The commonly used clinical treatment method of intractable ventricular fibrillation was adopted, such as continuous intravenous injection of 1 mg/kg lidocaine, while ascending aortic was re-blocked. The warm blood perfusion was given until the heart re-beated. The clinical outcomes were compared between the two groups. Results There was one perioperative death in the drug group and two deaths in the control group during perioperative period. Defibrillation frequency (3.11±0.59 times vs. 4.91±1.34 times, t=–2.917, P=0.000), heart rate 5 min after re-beating (91.65±9.81 beats/min vs. 98.32±10.21 beats/min, t=–2.019, P=0.032), cardiopulmonary bypass time (71.68±10.21 min vs. 81.59±12.93 min, t=–2.512, P=0.032), dopamine dosage (4.32±1.28 μg·kg–1·min–1 vs. 5.79±1.98 μg·kg–1·min–1, t=–2.781, P=0.015), epinephrine dosage (0.03±0.01 μg·kg–1·min–1 vs. 0.06±0.02 μg·kg–1·min–1, t=–3.996, P=0.000) and norepinephrine dosage (0.01±0.01 μg·kg–1·min–1 vs. 0.03±0.01 μg·kg–1·min–1, t=–4.163, P=0.000) of the drug group were significantly shorter or lower than those of the control group. The rate of cardiac rhythm 5 min after re-beating (42.8% vs. 9.4%, χ2=11.211, P=0.000) of the drug group was higher than that of the control group. Conclusion During intractable ventricular fibrillation following ascending aortic opening in valve replacemen, re-blocking the aorta and amiodarone reperfusion of the aortic root can significantly improve the heart re-beating rate and avoid ventricular re-fibrillation, shorten the cardiopulmonary bypass time and reduce the dosage of inotropic drugs.