ObjectiveTo compare the therapeutic effect of dual-chamber pacing (DDD) and ventricular single-chamber pacing (VVI) on arrhythmia via systematic evaluation. MethodsWith the method of Cochrane system evaluation, we searched Medline, Embase, CNKI, PubMed and Wanfang database (the searching time was up to June 30, 2016) for randomized controlled trials comparing DDD with VVI treatingcardiac arrhythmias. Meta analysis was performed using RevMan5.3 software. ResultsWe collected 12 randomized controlled trials of DDD and VVI pacing treating cardiac arrhythmia including 1 704 patients, but the quality of the studies were not good. The results of Meta analysis showed that:compared with VVI pacing mode, DDD pacing mode reduced the risk of atrial fibrillation[RR=0.36, 95%CI (0.22, 0.59), P < 0.000 1]; besides, it reduced the left atrial diameter[SMD=-0.43, 95%CI (-0.68, -0.17), P=0.001], the left ventricular end diastolic dimension[SMD=-0.33, 95%CI (-0.61, -0.05), P=0.02] and increased the left ventricular ejection fraction[SMD=1.03, 95%CI (0.49, 1.57), P=0.000 2]. ConclusionsComparing DDD with VVI on the treatment of cardiac arrhythmia in patients with cardiac arrhythmia, DDD pacing can reduce the incidence of atrial fibrillation and thrombosis, enhance heart function and improve blood supply. But because of the low quality of the included studies, the curative effect cannot be confirmed, and more randomized controlled trials with high quality needs to be carried out in the future.
Objective To summary the clinical experiences of ventricular septal myotomymyectomy on hypertrophic obstructive cardiomyopathy(HOCM) and investigate the treatment strategies during perioperative period for better clinical results. Methods From October 1996 to June 2009, 62 patients with HOCM underwent surgical treatment. There were 41 male and 21 female, aged 668 years with mean 34.05 years. The ventricular septal myotomymyectomy operation (Morrow operation or modified Morrow operation) was performed through the aortic incision under general anesthesia and hypothermic cardiopulmonary bypass (CPB). The concomitant operations included coronary artery bypass grafting (5 cases), mitral valve replacement (12 cases), mitral valve plasty(9 cases), aortic valve replacement (4 cases), tricuspid valve plasty(2 cases) and ductus arteriosus closure (2 cases). During the perioperative period, the patients were examined by echocardiography or transesophageal echocardiograph(TEE), electrocardiogram or dynamic echocardiogram and chest radiography. Left atrial diameter，left ventricular enddiastolic [CM(159mm]diameter，left ventricular outflow tract (LVOT) pressuregradient，interventricular septal thickness, ejection fraction[CM)](EF), the changes of mitral valve construction and function were evaluated. Results The time of CPB and aortic occlusion were 104.23±47.14 min and 66.76±36.32 min, respectively. The endotracheal intubation time was 13.23±11.76 h and the postoperative intensive care unit(ICU) stay was 42.53±37.41 h. Four patients died and the mortality was 6.45％(4/62). The main causes of death included septic shock complicated with acute renal failure(1 case), refractory arrhythmia, ventricular fibrillation, atrial flutter complicated with severe low cardiac output syndrome (1 case), severe acute renal failure(1 case) and Ⅲ°atrioventricular(AV) block complicated with low cardiac output syndrome(1 case). Postoperative left atrial diameter (34.56±6.45 mm vs.43.46±7.21 mm，t=6.948,P=0.000), left ventricular enddiastolic diameter (37.14±6.31 mm vs.42.03±6.23 mm，t=3.145,P=0.020), LVOT pressure gradient (23.54±17.78 mm Hg vs. 103.84±44.04 mm Hg,t=13.618,P=0.000) and interventricular septal thickness (17.12±5.67 mm vs.26.93±5.23 mm, t=10.694,P=0.000) decreased significantly compared with those before operation. There was no mitral valve regurgitation, or only mild mitral valve regurgitation. No systolic anterior motion(SAM) was found. The main postoperative arrhythmias included complete left bundle branch block, intraventricular block, complete atrioventricular block and atrial fibrillation. All the 58 cases were cured and discharged. Fiftythree cases were followed up for 3 months12 years, and 5 cases were lost. No death, complication and reoperation were found. Symptoms relieved significantly. The cardiac function was in New York Heart Association grade Ⅰ-Ⅱ. The quality of life improved significantly. Conclusion Most patients with HOCM can achieve satisfactory relief of LVOT obstruction and SAM via ventricular septal myotomymyectomy. The main arrhythmias after operation are bundle branch block and atrial fibrillation. Satisfactory effects can be achieved by accurate surgical technique and effective drug treatments.
Objective To explore how to differentiate the epilepsy and syncope in order to minimize the misdiagnosis. Methods Retrospectively analyzed the medical record of 6 cases which were misdiagnosed as epilepsy or syncope during April 2008 to September 2012 and reviewed the literatures about the differential diagnosis. Results Among the clinical characteristics, the ictal positional tone and loss of consciousness as well as the duration of postictal confusion are very important to the differential diagnosis. The ictal EEG shows highly rhythmic abnormal discharges when epileptic seizures occur. However, the ictal EEG would become slower and flatler during syncope. Conclusions When the automomic disorder and signs such as chest distress, arrhythmia. appear, the causes should not be limited in the cardiac diseases, the functional or structural abnormalities of the nervous system innervating the heart should also be considered; on the contrary, convulsions might not only due to the abnormal electrical activity in the brain, but syncope.
Lorenz plot (LP) method which gives a global view of long-time electrocardiogram signals, is an efficient simple visualization tool to analyze cardiac arrhythmias, and the morphologies and positions of the extracted attractors may reveal the underlying mechanisms of the onset and termination of arrhythmias. But automatic diagnosis is still impossible because it is lack of the method of extracting attractors by now. We presented here a methodology of attractor extraction and recognition based upon homogeneously statistical properties of the location parameters of scatter points in three dimensional LP (3DLP), which was constructed by three successive RR intervals as X, Y and Z axis in Cartesian coordinate system. Validation experiments were tested in a group of RR-interval time series and tags data with frequent unifocal premature complexes exported from a 24-hour Holter system. The results showed that this method had excellent effective not only on extraction of attractors, but also on automatic recognition of attractors by the location parameters such as the azimuth of the points peak frequency (APF) of eccentric attractors once stereographic projection of 3DLP along the space diagonal. Besides, APF was still a powerful index of differential diagnosis of atrial and ventricular extrasystole. Additional experiments proved that this method was also available on several other arrhythmias. Moreover, there were extremely relevant relationships between 3DLP and two dimensional LPs which indicate any conventional achievement of LPs could be implanted into 3DLP. It would have a broad application prospect to integrate this method into conventional long-time electrocardiogram monitoring and analysis system.
Objective To improve the myocardial protection result, observe the effects of 11,12 epoxyeicosatrienoic acid (11,12 EET) on reperfusion arrhythmias in the isolated perfused immature rabbit hearts, which underwent long term preservation. Methods Sixteen isolated rabbit hearts were randomly assigned to two groups, 8 rabbits each group. Control group: treated with St.Thomas Ⅱ solution, experimental group: treated with St.Thomas Ⅱ solution plus 11,12 EET. By means of the Langendorff technique, these isolated rabbit hearts were arrested and stored for 16 hours with 4℃ hypothermia, and underwent 30 minutes of reperfusion(37℃). The mean times until the cessation of both electrical and mechanical activity were measured after infusion of cardioplegia. The heart rate (HR), coronary flow (CF), myocardial water content (MWC), value of creatine kinase (CK) and lactic dehydrogenase (LDH), myocardial calcium content and the arrhythmias score (AS) during the period and at the endpoint of the reperfusion were observed. Results The times until electrical and mechanical activity arrest in the experimental group were significantly shorter than those in control group ; HR, CF, MWC, CK, LDH, myocardial calcium content and AS were significantly better than those in control group. Conclusions These data suggest that 11,12 EET added to the cardioplegic solution of St.Thomas Ⅱ has lower incidence rate of reperfusion arrhythmias.
The cardiac conduction system (CCS) is a set of specialized myocardial pathways that spontaneously generate and conduct impulses transmitting throughout the heart, and causing the coordinated contractions of all parts of the heart. A comprehensive understanding of the anatomical characteristics of the CCS in the heart is the basis of studying cardiac electrophysiology and treating conduction-related diseases. It is also the key of avoiding damage to the CCS during open heart surgery. How to identify and locate the CCS has always been a hot topic in researches. Here, we review the histological imaging methods of the CCS and the specific molecular markers, as well as the exploration for localization and visualization of the CCS. We especially put emphasis on the clinical application prospects and the future development directions of non-destructive imaging technology and real-time localization methods of the CCS that have emerged in recent years.
Arrhythmia is a significant cardiovascular disease that poses a threat to human health, and its primary diagnosis relies on electrocardiogram (ECG). Implementing computer technology to achieve automatic classification of arrhythmia can effectively avoid human error, improve diagnostic efficiency, and reduce costs. However, most automatic arrhythmia classification algorithms focus on one-dimensional temporal signals, which lack robustness. Therefore, this study proposed an arrhythmia image classification method based on Gramian angular summation field (GASF) and an improved Inception-ResNet-v2 network. Firstly, the data was preprocessed using variational mode decomposition, and data augmentation was performed using a deep convolutional generative adversarial network. Then, GASF was used to transform one-dimensional ECG signals into two-dimensional images, and an improved Inception-ResNet-v2 network was utilized to implement the five arrhythmia classifications recommended by the AAMI (N, V, S, F, and Q). The experimental results on the MIT-BIH Arrhythmia Database showed that the proposed method achieved an overall classification accuracy of 99.52% and 95.48% under the intra-patient and inter-patient paradigms, respectively. The arrhythmia classification performance of the improved Inception-ResNet-v2 network in this study outperforms other methods, providing a new approach for deep learning-based automatic arrhythmia classification.
Objective To systematically review the health economic evaluations of using long-term rhythm-control antiarrhythmic drugs (AAD) for patients with paroxysmal or persistent atrial fibrillation (AF). Methods Databases including PubMed, EMbase, Scopus, CNKI, SinoMed, WanFang Data, and official websites of well-established health technology assessment (HTA) institutions were electronically searched to present the economic evaluations of AAD and the recommendations of HTA institutions based on drug economy from inception to April 23rd, 2022. Two reviewers independently screened the literature, extracted data and systematic review was then performed. Results A total of 19 studies were included, including 11 cost-effectiveness or cost-utility analysis studies and 8 official documents from HTA institutions. Only 5 (45.5%) economic evaluations were of relatively high quality, and English language studies were of higher quality than Chinese language studies ones. The included studies lacked elements that CHEERS 2022 concerns, such as health economics analysis plans, equity and distributional effects, engagement with patients and other stakeholders and the impact on the study. Dronedarone and amiodarone were the main focus of the evaluation, and the study results showed that dronedarone was cost-effective compared with other drugs in different study designs and national settings. However, there were differences between the recommendations of HTA agencies and the results of economic evaluation studies. Conclusion The completeness of health economics evaluations needs to be improved, along with the quality of clinical evidence in the field of AF-AAD for Chinese patients. Additionally, the informational value of drugs should be thoroughly investigated through budget impact analysis and distributional cost-effectiveness analysis to provide evidence of high-quality studies for decision-makers in China.