Objective  To investigate the importance of standard operation of ECG examination for quality control of remote ECG network. Methods  We analyzed ECGs transmitted through the network from January 1,2022 to June 30,2023 at the ECG Network Center of the First People’s Hospital of Xianyang. During the time period, we took every six months as a stage, and performed targeted operation training of ECG examination at each stage. We compared the graphic quality problems and the number of ECGs with quality problems among different stages. Results  After regular ECG operation training for clinical medical staff and instrument maintenance, the quality of ECG graphics has been greatly improved. Conclusion  Standard operation of remote ECG network directly affects the diagnostic accuracy of ECGs. Regular standardized training of ECG operation for clinical medical staff could improve the accuracy of ECG examination results, and avoid the occurrence of medical adverse events.

Objective  To investigate the changes of serum creatine kinase isoenzyme (CK-MB), homocysteine (Hcy) and B-type natriuretic peptide (BNP) levels in patients with acute myocardial infarction (AMI), and to analyze their correlation with the severity of the disease and their predictive value on major adverse cardiovascular events (MACEs). Methods   A total of 102 patients with AMI were selected as the research group while another 102 healthy physical examinees during the same period were selected as the control group. The changes of serum CK-MB, Hcy and BNP levels were compared separately between different groups and among the enrolled patients with different numbers of coronary lesions. Spearman and Pearson correlation analysis was utilized to explore the correlation between serum indicators and the number of coronary lesions or Gensini score. Patients in the research group were treated by percutaneous coronary intervention (PCI). They were divided into subgroups with or without MACEs according to the presence or absence of MACEs 6 months after the surgery. The serum CK-MB, Hcy and BNP levels were analyzed in each group before PCI and one month after the surgery. The predictive value of each serum indicator level one month after operation on MACEs was analyzed by using ROC curve. ResultsThe serum levels of CK-MB, Hcy and BNP in the research group were higher than those in the control group (P<0.01); serum CK-MB, Hcy and BNP levels were positively correlated with the number of coronary lesions and Gensini score (P<0.05). One month after surgery, the serum CK-MB, Hcy and BNP levels of the patients with MACEs were higher than those of the patients without MACEs (P<0.05). The AUC value of the combination of serum CK-MB, Hcy and BNP levels one month after surgery for MACEs was 0.943, which was higher than the AUC value of single indicator (0.769, 0.847 and 0.794, respectively;P<0.05). Conclusion  The serum levels of CK-MB, Hcy and BNP in AMI patients are elevated, which are closely related to the severity of the disease. The combined detection of the above serum indicators has certain predictive value for the occurrence of MACEs.

Cancer is the second leading cause of mortality worldwide, and a quarter of global cancerrelated deaths occur in China. At present, cardiovascular disease has emerged as the second most common cause of death among cancer survivors subsequent to cancer recurrence and metastasis. Accurate prediction and early diagnosis of potential cardiovascular toxicity during cancer treatment could not only optimize patients clinical outcomes but also could alleviate the burden on the healthcare system. This article provides a comprehensive overview of recent research pertaining to predicting and early diagnosing cancer therapyrelated cardiovascular toxicity, offering valuable insights into identifying highrisk patients.

Objective   To explore the principles and clinical applications of CR lead ECGs. Methods   The CR lead system is a bipolar chest lead system with a common negative electrode. The right upper limb (R) is its common negative electrode,  the positive electrode is a point on the chest (C), and  each point of  V leads were multiply chosen. We can obtain CR lead ECGs by the following  two methods. The first method is to make direct acquisition by a conventional ECG machine, with all four limb electrodes connected to the right upper limb and the chest lead electrode connected normally. The second method is to obtain CR lead ECGs through lead conversion based on conventional ECG data. First, the original data of leads such as aVR, V1-V6, V3R-V5R and V7-V9 were retrieved, and then a fixed conversion coefficient CR-Vi=Vi－2/3aVR was used to calculate the target lead (the algorithm was implemented under the compiling environment of Pycharm in Python language); finally, the conversion is completed and plotted. ResultsBoth the direct acquisition method and the conversion method obtained the same CR lead ECGs. However, compared with the corresponding Wilson lead ECG,  CR lead ECG in the left chest lead had a similar morphology but slightly great wave amplitudes while  CR lead ECG in the right chest lead had similar wave amplitudes but distinctly different wave morphology. The CR lead ECG in the right chest lead had a clear P wave, an upward QRS complex with no wide or deep Q wave, and an upright T wave. Wilson lead ECG had a lower P wave, a downward QRS complex, and could exhibit noninfarctionrelated wide and deep Q waves and nonischemic T wave inversion, known as the socalled right ventricular blind zone. Conclusion  CR lead ECG opens up the right ventricular blind zone, and achieves equal detection of the left and right ventricles, providing more valuable ECG morphological information for clinical practice and compensating for the limitations of the Wilson chest lead system. It is worthy of being promoted and popularized.

患者男，28岁，因“突发心慌4 h”入院。入院时诊断为室上性心律失常。静脉推注普罗帕酮复律后，患者心电图提示室性心动过速(简称室速)，随即意识丧失，予以非同步电复律，抢救成功，后入院行心内电生理检查，证实为房室结折返性心动过速，行导管消融术，消融治疗成功。经反复心内电生理检查，未诱发室速，证实室速为普罗帕酮所致。本文对普罗帕酮导致的室速病例进行分析，旨在为该药的临床安全应用提供参考，同时提醒医疗人员注意：使用抗心律失常药物可能有促心律失常作用，使用时应进行严密心电监测。

Objective  To explore the diagnostic value of Peguero-Lo Presti index on heart failure with preserved ejection fraction (HFpEF). Methods  We selected patients with clinical symptoms of heart failure (HF) who had been hospitalized in the Department of Cardiology of Provincial Clinical Medical College, Fujian Medical University; their clinical data were complete, including ECGs, cardiac ultrasound, biochemistry, and NT-proBNP. Based on the HFA-PEFF score standard recommended by the Guidelines for the diagnosis and treatment of acute and chronic HF, 120 patients were enrolled in the HFpEF group (60 males and 60 females) while 100 cases without HF were divided into the control group (56 males and 44 females). The baseline data characteristics were compared between the two groups. Peguero-Lo Presti index, Cornell product index, and RomhiltEstes score were separately calculated and analyzed in the standard 12lead ECGs. We compared the area under the ROC curve, sensitivity and specificity of the above three indicators for diagnosing HFpEF. Results  Compared with the control group, there was no statistically significant difference in the baseline data such as sex, age, diabetes proportion, coronary heart disease, highdensity lipoprotein cholesterol, and serum creatinine in the HFpEF group (P>0.05); the proportion of hypertension, lowdensity lipoprotein cholesterol and hyperuricemia increased (P<0.05). In the male subgroup, the area under the ROC curve of the Peguero-Lo Presti index was 0.84 (0.76, 0.90), which was higher than that of the Cornell product index \[0.70 (0.61, 0.78)\] and that of the Romhilt-Estes score[0.62 (0.53, 0.71)\ (all P<0.05). The sensitivity of the PegueroLo Presti index was 6667%, which was higher than that of the Romhilt-Estes score (36.57%) and that of the Cornell product index (48.33%), with statistically significant differences (all P<0.05) while the difference of specificity was not statistically significant. In the female subgroup, the area under the ROC curve of the Peguero-Lo Presti index was 0.77 (0.69, 0.85), which was higher than that of the Cornell product index [0.68 (0.58, 0.77)] and that of the Romhilt-Estes score [0.57(0.47, 0.66)， all P<0.05］. The sensitivity of the Peguero-Lo Presti index was 68.33%, which was higher than that of the Romhilt-Estes score (26.67%), with statistically significant difference (P<0.01) while the difference of specificity was not statistically significant. Conclusion  The Peguero-Lo Presti index of ECG has high sensitivity and specificity for diagnosing HFpEF. The examination method is convenient, and could be used as an auxiliary diagnosis and screening index for HFpEF clinically.

Objective  To analyze the value of arteriosclerosis index combined with pulse pressure index in predicting the degree of coronary artery lesions in patients with coronary heart disease (CHD). Methods  Seventy-two patients with CHD were selected, and divided into singlebranch group (21 cases), double-branches group (34 cases) and threebranches group (17 cases) according to the number of lesioned coronary arteries. Arteriosclerosis index and pulse pressure index were compared among the three groups. Pearson correlation analysis was used to explore the relationship between the indexes and the degree of coronary artery lesions. ROC curve was drawn to analyze the predictive value of the combined index. Results  The arteriosclerosis index and Gensini score of the threebranches group were higher than those of the other two groups, and the pulse pressure index was higher than that of the singlebranch group. Arteriosclerosis index and Gensini score in the doublebranches group were higher than those in the singlebranch group (P<0.05). The arteriosclerosis index and pulse pressure index were both positively correlated with Gensini score. ROC curve was drawn taking the double and threebranches groups as a whole and the singlebranch group as the control. The results showed that arteriosclerosis index and pulse pressure index had certain predictive value for the degree of coronary artery disease in patients with CHD (AUC=0.897 and 0.697,respectively), and the combined detection had greater predictive value (AUC=0.924). Conclusion  Arteriosclerosis index and pulse pressure index are closely related to the degree of coronary artery disease in patients with CHD. The combined detection of the two indexes has greater predictive value for the degree of coronary artery disease.

Handheld ECG collector is a simple bipolar singlelead ECG recording device. A standard Ⅰlead ECG can be conveniently recorded just by pressing the positive and negative electrodes with both thumbs. It is mainly utilized in the monitoring of arrhythmias. As a household medical equipment, it is quite popular with the majority of middleaged and elderly friends. Based on the nature of unipolar  and bipolar leads, and their intrinsic connection, this paper derives a recording method of standard leads and augmented unipolar leads. Meanwhile, on the basis of further exploring the internal connection between CR lead and Wilson lead, the method of directly recording CR chest lead ECGs by handheld ECG collector is creatively proposed. Both theory and practice show that the equivalent recording method of augmented unipolar limb lead and the bipolar recording method of CR chest lead can not only meet the clinical needs, but also prove to be unique. This method can fully develop the medical value of household medical devices, which is worthy of be promoted and popularized.

Objective  To compare the effectiveness and safety of secondgeneration cryoballoon ablation and conventional drug therapy separately as the initial treatment for patients with paroxysmal atrial fibrillation (AF). Methods  We selected 44 patients with paroxysmal AF who had been initially treated by secondgeneration cryoballoon ablation as the ablation group. The operation time, ablation time, X-ray fluoroscopy time, pulmonary vein isolation rate, and surgical complications were observed. We selected another 44 inpatients with paroxysmal AF who had been initially treated by drug therapy during the same period as the medication group. The two groups were followed up separately one month, and 3, 6 and 12 months after discharge to observe the recurrence rate and complications of AF. The efficacy and safety of treatment were further compared between the two groups. Results  The operation time, ablation time and X-ray fluoroscopy time of the ablation group were (108.0±39.0) minutes, (35.0±11.7) minutes and (10.0±6.9) minutes, respectively; the immediate isolation rate of pulmonary vein was 100%; there were 3 cases (6.8%) of operationrelated complications, including one case of vagus reflex and 2 cases of transient phrenic nerve injury. In the medication group, drug-induced sinus bradycardia occurred in 2 cases, QTc was prolonged in one case, and thyroid function was decreased in one case. After a mean follow-up of (12.0±5.) months, the recurrence rate of AF was 11.4% in the ablation group while the rate was 20.5% in the medication group. The recurrence rate in the ablation group was significantly lower than that in the medication group (P=0.033). The incidence of complications or adverse reactions did not vary significantly from the ablation group to the medication group (6.8% vs 9.1%, P=0.108). Conclusion  Compared with drug therapy, the secondgeneration cryoballoon ablation has a higher success rate for paroxysmal AF without increased risk of complications. The secondgeneration cryoballoon ablation can be considered as one of the initial treatment strategies for paroxysmal AF.

Objective  To investigate the application value of 24hour ambulatory electrocardiography (AECG) in the diagnosis of silent myocardial ischemia (SMI). Methods  A total of 135 patients with suspected SMI were selected as the research subjects, and they underwent both routine ECG and 24-hour AECG. The detection rate of SMI was compared between the two examination methods. The diagnostic efficiency of SMI was analyzed by using coronary angiography (CAG) as the gold standard. Results  Among the 135 patients suspected with SMI, 107 cases were confirmed by CAG. Ninety-two cases were detected by routine ECG with a positive detection rate of 85.98% (92/107) while 24-hour AECG detected 102 cases with a positive rate of 95.33% (102/107). The positive rate of 24-hour AECG proves to be significantly higher than that of routine ECG (χ2=5.515, P=0.019). The diagnostic sensitivity, accuracy rate and negative predictive value of 24-ccuracy in the diagnosis of SMI.

Atrial fibrillation (AF) has become an important disease that endangers the health of middle-aged and elderly people in China, and it is related to the risk of stroke and death. At present, pathophysiological mechanisms such as atrial structural remodeling, electrical remodeling, inflammation, autonomic nervous system disorders, and non-coding RNA may explain the occurrence and development of AF. The treatment of AF mainly includes anticoagulation, conversion of sinus rhythm, and control of ventricular rate. In addition, antiinflammatory, autonomic nerve intervention and genomics intervention therapy may become  new types of therapies for AF. This article reviews the research progress in the   pathogenesis and treatment of AF.

In recent years, the combination of remote ECG monitoring and artificial intelligence (AI) technology has greatly assisted the diagnosis and treatment of cardiovascular diseases, and shows extremely broad development prospect. This paper summarizes the progress in the application of AIbased remote ECG monitoring technology in the intelligent diagnosis, hierarchical diagnosis and treatment, prognosis evaluation, and individualized management of acute coronary syndrome. It also introduces the active health intelligent management system of the heart which has been constructed and gradually improved in China on this basis.

同时发生前壁和下壁急性ST段抬高型心肌梗死较为少见，其梗死相关血管主要为包绕心尖型左前降支闭塞。本例患者男，57岁，因被发现神志不清2 h入院。急诊心电图检查示：窦性心律，V3—V6、Ⅱ、Ⅲ、aVF导联ST段抬高0.1~0.5 mV。急诊冠状动脉造影证实其梗死相关血管为右冠状动脉近段完全闭塞。

电张调整性T波的累积作用引起的T波改变属于功能性改变，对其充分认识并正确判断，可以避免一些不必要的特殊检查及治疗。特发性室性心动过速频繁发作时，可显示出电张调整性T波改变。  本文对典型的电张调整性T波改变患者前后相隔一周的两次动态心电图进行比较和分析，探讨电张调整性T波改变后的累积作用及其与特发性室性心动过速持续时间与次数的关系。

In the past, it has been generally accepted that tachyarrhythmias other than atrial fibrillation (AF) such as atrial premature beats (APB) and atrial tachycardia (AT) are not of great clinical significance. However, with the development of detection methods in recent years, more and more clinical studies have found that the atrial ectopic activities of APB and AT except for AF are associated with the risk of stroke, and may further contribute to increased mortality. Meanwhile, a positive association has also been revealed between the frequency of this kind of atrial yarrhythmias, and incidence of adverse events such as AF and ischemic stroke, which may be mediated by subclinical atrial cardiomyopathy. There is still no clear definition of the clinical threshold for this type of arrhythmia and its excessive supraventricular ectopic activities at present. Therefore, it is essential to make regular detection and management of tachyarrhythmia other than AF by means such as ambulatory electrocardiography and by following standardized process. This article describes the relationship between such atrial arrhythmias and cardiogenic stroke, and introduces the role of detecting such arrhythmias in the assessment of cardiogenic stroke.

Atrial fibrillation (AF) is one of the most common arrhythmias with high disability rate and mortality, which seriously affects the quality of patients  life. Thromboembolism is one of the most serious complications of AF, however, the mechanism of thromboembolism caused by AF has not been fully clarified at present. Some biomarkers and risk scores could be applied in predicting the occurrence and development of AF related thromboembolism. This paper reviews the research progress in risk factors of thromboembolism among patients with AF in terms of  patients  basic data, laboratory examinations, echocardiography, etc.

Many commonly used medications have the potential to induce QT interval or QTc prolongation, subsequently leading to torsade de pointes (TdP) and other arhythmias, which may further deteriorate into ventricular fibrillation and even sudden cardiac death. Therefore, it is crucial to  make identification, early warning and correction of risk factors in order to prevent and reduce the risk of druginduced QT interval prolongation and TdP. In recent years, clinical decision support systems and other early warning strategies have been widely employed for predicting QT interval or QTc prolongation by identifying various risk factors, and  warning to the highrisk population susceptible to TdP. This article summarizes drugs and related risk factors that contribute to prolonged QT interval and TdP risk, as well as concludes the existing warning measures, aiming to offer guidance for managing patients exposed to the related risks.

Atrial fibrillation (AF) is the most common arrhythmia and may easily lead to various complications. Therefore, precision medical methods are needed to identify and enhance AF detection to achieve early diagnosis and treatment. Artificial intelligencebased wearable devices are of great value for the screening and management of AF patients. This article reviews the relevant literature on recent applications of such devices for AF screening.

Objective  To evaluate the efficacy and safety of the domestic Columbus 2.0 three-dimension (3D) cardiac electrophysiological mapping system and its supporting catheter in the treatment of tachyarrhythmias through a prospective, multicenter and singlearm study. Methods  We selected 50 consecutive patients with tachyarrhythmias from 4 electrophysiological centers of Shanghai;  20 patients (40.0%) are males, the mean age of patients is (55.38±18.14) years old. Radiofrequency ablation was performed on these patients guided by Columbus 2.0 system and its supporting catheter. The immediate success rate, operation time, X-ray exposure time and dose, and adverse events were recorded. All the patients were followed up for 6 months. Results  There are 34 patients with atrioventricular nodal reentry tachycardia, 11 cases with atrioventricular reentry tachycardia, one with atrial tachycardia, one with typical  atrial flutter, and 3 patients with premature ventricular ntraction.  The immediate success rate of the procedure is 100%; no catheter ablation related adverse event occurs during the perioperative period. The average operation time is 114.00 (89.75, 166.25) min, the  average X-ray exposure time is 5.90 (3.78, 8.07) min, and the  average X-ray exposure dose is 23.96 (8.00, 50.00) mGy. There is no recurrence during 6 months of follow-up.  Conclusion  The efficacy and safety of Columbus  2.0 3D cardiac electrophysiological mapping system and its supporting catheter is satisfying in treating tachyarrhythmias, especially supraventricular arrhythmias.

本文报道1例中年患者，因心悸入院，既往无特殊病史，考虑预激综合征可能；入院拟择期行心内电生理检查±射频消融术，术中发现体内丝状异物。经仔细核查分析后，考虑该异物系穿刺时塑胶型导丝部分断裂并遗留于体内，顺血流漂至肺动脉处，经圈套器取出后继续完成消融手术，未造成不良后果，患者安全出院。

Objective  To analyze the ECG characteristics of patients with human immunodeficiency virus (HIV) infection and acquired immunodeficiency syndrome (AIDS) among Zhuang ethnic group in Guangxi Zhuang Autonomous Region so as to provide clinical basis for the diagnosis and treatment of this kind of population. Methods  We selected 200 cases infected with HIV and 200 AIDS patients from inhabitants of Guangxi Zhuang Autonomous Region who had been hospitalized in our hospital, separately as infection group and patient group. In addition, 200 healthy physical examinees during the same time period were selected as control group. Routine 12-lead ECG detection was performed on the three groups of research subjects. We compared active arrhythmia, passive arrhythmia, ST-T changes, QT interval/QTc prolongation and other abnormal ECG changes. Results  In the infection group and the patient group, the incidences of active arrhythmias, passive arrhythmias, QT interval/QTc prolongation were all significantly higher than those in the control group. The incidences of the above three abnormal ECG changes in the patient group were also significantly higher than those in the infection group (all P<0.05). Conclusion  Abnormal ECG changes are more common among patients with HIV infection and AIDS in Guangxi Zhuang population, mainly arrhythmias, ST-T changes and QT interval/QTc prolongation. Clinicians need to pay close attention to abnormal ECG changes of patients with HIV infection and AIDS patients among these population in order to prevent adverse cardiac events.

Objective  To evaluate the impact of pulmonary vein anatomical variations on the efficacy of cryoablation in patients with persistent atrial fibrillation. Method  A retrospective analysis was conducted on the clinical data of 98 patients with persistent atrial fibrillation who had undergone cryoballoon ablation. According to the presence or absence of pulmonary vein variations, they were divided into pulmonary vein variation group (variants group, 21 cases) and non-pulmonary vein variation group (normal group, 77 cases). The procedure time, duration and dose of X-ray exposure, intraoperative complications, procedure success rate of isolation, and each follow-up index were compared between the two groups. Results  Compared with the normal group, the ablation procedure time\[(35.1±13.4) min vs. (64.3±17.7) min] and X-ray exposure time [(22.3±5.8) min vs. (33.6±6.0) min] of the variants group were both longer (P<0.01) while the CD value of radiation exposure [(607.1±212.9) mGy vs. (1 018.5±280.8) mGy] significantly increased (P<0.01). In the normal group, the success rate of primary isolation was significantly higher than that in the variants group (75/77 vs. 16/21, P=0.01). However, both groups completed pulmonary vein isolation 100% at the end of procedure. The recurrence rate of the two groups did not vary significantly during one-year follow-up (19/77 vs. 6/21, P=0.726). Conclusion  For patients with persistent atrial fibrillation and pulmonary vein variations, the acute-stage and long-term success rates of cryoablation are similar to the rates in the patients without pulmonary vein variation. However, patients with pulmonary vein variations have prolonged procedure time and increased radiation exposure.

Objective  To observe the clinical efficacy and safety of left bundle branch pacing (LBBP) in patients with persistent atrial fibrillation (PAF) complicating slow ventricular rate. Methods  Fifty-six patients who had undergone pacing treatment due to PAF complicating slow ventricular rate were selected. The patients were divided into right ventricular septal pacing (RVSP) group (29 cases) and LBBP group (27 cases) based on the implantation site of ventricular pacing electrode. Each group was further divided into heart failure (HF) and non-HF subgroups according to clinical symptoms and related examination results. The changes of pacing parameters (such as threshold, perception and impedance), ECG, echocardiography, and plasma probrain natriuretic peptide (NT-proBNP) were observed during operation and 12 months after operation. Other conditions including pacing related complications, re-hospitalization due to HF, newly emerging cerebral infarction and all cause death were also observed. Results(ⅰ) There is no statistically significant difference in pacing parameters between the two groups (P>0.05). The NT-proBNP level of HF patients in both subgroups decreases 12 months after surgery compared with that before, however its reduction in the HF subgroup of the RVSP group is not significant (P>0.05). (ⅱ) In the RVSP group, there is no significant difference in LVEF or LVDd 12 months after surgery compared with that before (P>0.05); LAD signific antly increases (P<0.05) while mitral regurgitation is obviously worsened (P<0.05). In the LBBP group, there is no significant change in LAD or mitral regurgitation 12 months after surgery compared with that before (P>0.05); LVEF increases while LVDd decreases in those with HF 12 months after surgery (P<0.05). (ⅲ) Compared with that before operation, QRS complex duration is prolonged in both groups (P<0.05), and its value in the RVSP group is significantly greater than that in the LBBP group (P<0.05). (ⅳ) There is no significant difference in pacing related complications or cardiovascular and cerebrovascular events between the two groups (P>0.05); the re-hospitalization rate in the RVSP group is higher than that in the LBBP group (P<0.05).Conclusion  Among patients with PAF complicated by slow ventricular rate, LBBP  helps to delay or reverse left ventricular remodeling of those with HF, improve cardiac function, and reduce readmission rate due to HF. LBBP should be recommended as the preferred pacing treatment method for atrial fibrillation patients with slow ventricular rate.

Objective  To study the changes and significance of serum Hcy and NT-proBNP levels in patients with chronic heart failure. Methods  We selected 102 patients with chronic heart failure as the observation group while another 102 healthy physical examinees  during the same period were enrolled as the control group. The serum Hcy and NT-proBNP levels were separately tested in the two groups, and made comparison. Meanwhile, left ventricular ejection fraction (LVEF) was measured. The correlation between serum Hcy, NT-proBNP and LVEF was analyzed. Results  The serum Hcy and NT-proBNP levels of the observation group before and after treatment were higher than those of the control group while LVEF  was  lower than that of the control group with statistically significant differences (P<0.05). Before treatment, the levels of serum Hcy and NT-proBNP in the observation group increased with the upgraded NYHA grading while  LVEF decreased; there was a statistically significant difference of each index among the patients with different NYHA grades in pairwise comparison (P<0.05). The levels of serum Hcy and NT-proBNP were negatively correlated with LVEF (P<0.05) before treatment. Conclusion  The changes of serum Hcy and NT-proBNP levels could reflect the cardiac function grading and severity of patients with chronic heart failure.

Deceleration capacity of rate (DC) is one of the indicators reflecting the function of autonomic nervous regulation. Due to its noninvasiveness, and high sensitivity and specificity, it had been widely used in the prognosis and sudden death risk assessment of cardiovascular diseases at present. In recent years, domestic and foreign researchers have applied DC detection to research related to diseases other than heart diseases, and have made great progress. This article reviews the clinical research progress related to DC at home and abroad, aiming to further comprehensively and systematically sort out the clinical application value and potential  of DC.

大部分心房颤动（简称房颤）的散点图形状特征为扇形，其中为完全无规律的散点，面积大小不等，扇叶边缘锋利，与坐标轴保持一定的距离和夹角。房颤散点图呈规则矩形的较少见。本文报告1例老年阵发性房颤患者，心电散点图呈矩形，并探讨其形成机制，为分析动态心电报告提供更多诊断思路。

病理性Q波在心电学诊断中较为常见，可见于心肌梗死患者，也可由其他病因所致。本文就临床诊治的心电图均表现为病理性Q波的3例病例，从心电向量图特征、临床病史及相关检查等方面，对其病理性Q波的形成进行解析，以期为病理性Q波的诊断与鉴别诊断提供新的分析思路。

Atrial fibrillation (AF) is one of the most common arrhythmias. It is characterized by concealment, paroxysmal nature, complexity, and high mortality and disability rate; the prevalence rate of AF is on the rise. The new emergence of artificial intelligence technology breaks through the limitations of traditional methods of AF screening, showing unique advantages and broad application prospects in the screening, diagnosis and prediction of AF. Intelligent wearable devices have higher feasibility, specificity and sensitivity in the screening  of AF, with high cost-effectiveness in clinical application.