Current use of oral anticoagulation therapy and influencing factors among coronary artery disease patients with nonvalvular atrial fibrillation in China / 中华心血管病杂志

Objective: To investigate current use of oral anticoagulant (OAC) therapy and influencing factors among coronary artery disease (CAD) patients with nonvalvular atrial fibrillation (NVAF) in China. Methods: Results of this study derived from "China Atrial Fibrillation Registry Study", the study prospectively enrolled atrial fibrillation (AF) patients from 31 hospitals, and patients with valvular AF or treated with catheter ablation were excluded. Baseline data such as age, sex and type of atrial fibrillation were collected, and drug history, history of concomitant diseases, laboratory results and echocardiography results were recorded. CHA2DS2-VASc score and HAS-BLED score were calculated. The patients were followed up at the 3rd and 6th months after enrollment and every 6 months thereafter. Patients were divided according to whether they had coronary artery disease and whether they took OAC. Results: 11 067 NVAF patients fulfilling guideline criteria for OAC treatment were included in this study, including 1 837 patients with CAD. 95.4% of NVAF patients with CAD had CHA2DS2-VASc score≥2, and 59.7% of patients had HAS-BLED≥3, which was significantly higher than NVAF patients without CAD (P<0.001). Only 34.6% of NVAF patients with CAD were treated with OAC at enrollment. The proportion of HAS-BLED≥3 in the OAC group was significantly lower than in the no-OAC group (36.7% vs. 71.8%, P<0.001). After adjustment with multivariable logistic regression analysis, thromboembolism(OR=2.48,95%CI 1.50-4.10,P<0.001), left atrial diameter≥40 mm(OR=1.89,95%CI 1.23-2.91,P=0.004), stain use (OR=1.83,95%CI 1.01-3.03, P=0.020) and β blocker use (OR=1.74,95%CI 1.13-2.68,P=0.012)were influence factors of OAC treatment. However, the influence factors of no-OAC use were female(OR=0.54,95%CI 0.34-0.86,P=0.001), HAS-BLED≥3 (OR=0.33,95%CI 0.19-0.57,P<0.001), and antiplatelet drug(OR=0.04,95%CI 0.03-0.07,P<0.001). Conclusion: The rate of OAC treatment in NVAF patients with CAD is still low and needs to be further improved. The training and assessment of medical personnel should be strengthened to improve the utilization rate of OAC in these patients.

The relationship between fasting blood glucose level and thromboembolism events in patients with non-valvular atrial fibrillation / 中华心血管病杂志

Objective: To explore the relationship between fasting blood glucose level and thromboembolism events in patients with non-valvular atrial fibrillation (NVAF). Methods: This was an observational study based on data from a multicenter, prospective Chinese atrial fibrillation registry cohort, which included 18 703 consecutive patients with atrial fibrillation (AF) in 31 hospitals in Beijing from August 2011 to December 2018. Patients were divided into 5 groups according to status of comorbid diabetes and fasting glucose levels at admission: normal blood glucose (normal glucose group), pre-diabetes group, strict glycemic control group, average glycemic control group and poor glycemic control group. Patients were followed up by telephone or outpatient service every 6 months. The primary follow-up endpoint was thromboembolic events, including ischemic stroke and systemic embolism. The secondary endpoint was the composite endpoint of cardiovascular death and thromboembolic events. Kaplan-Meier survival analysis and multifactorial Cox regression were used to analyze the correlation between fasting glucose levels and endpoint events. Results: The age of 18 703 patients with NVAF was (63.8±12.0) years, and there were 11 503 (61.5%) male patients. There were 11 877 patients (63.5%) in normal blood glucose group, 2 023 patients (10.8%)in pre-diabetes group, 1 131 patients (6.0%) in strict glycemic control group, 811 patients in average glycemic control group and 2 861 patients(4.3%) in poor glycemic control group. Of the 4 803 diabetic patients, 1 131 patients (23.5%) achieved strict glycemic control, of whom 328 (29.0%) were hypoglycemic (fasting blood glucose level<4.4 mmol/L at admission). During a mean follow-up of (51±23) months (up to 82 months), thromboembolic events were reported in 984 patients (5.3%). The survival curve analysis of Kaplan Meier showed that the incidence rates of thromboembolic events in normal glucose group, pre-diabetes group, strict glycemic control group, average glycemic control group and poor glycemic control group were 1.10/100, 1.41/100, 2.09/100, 1.46/100 and 1.71/100 person-years, respectively (χ²=53.0, log-rank P<0.001). The incidence rates of composite endpoint events were 1.86/100, 2.17/100, 4.08/100, 2.58/100, 3.16/100 person-years (χ²=72.3, log-rank P<0.001). The incidence of thromboembolic events and composite endpoint events in the other four groups were higher than that in the normal blood glucose group (P<0.001). Multivariate Cox regression analysis showed that compared with normal glucose group, the risk of thromboembolism increased in pre-diabetes group(HR=1.23, 95%CI 1.00-1.51, P=0.049), strict glycemic control group(HR=1.32, 95%CI 1.06-1.65, P=0.013) and poor glycemic control group(HR=1.26, 95%CI 1.01-1.58, P=0.044). Conclusion: Both high or low fasting glucose may be an independent risk factor for thromboembolic events in patients with NVAF.

Feasibility and safety of intracardiac ultrasound-assisted atrial septal puncture during radiofrequency ablation for atrial fibrillation / 中华心血管病杂志

Objective: To explore the feasibility and safety of intracardiac ultrasound-assisted atrial septal puncture (ASP) during radiofrequency ablation for atrial fibrillation. Methods: We enrolled 241 consecutive patients scheduled to radiofrequency ablation for atrial fibrillation in Beijing Anzhen Hospital from July to September 2020. Inclusion criteria: patients aged over 18 years with a clear electrocardiogram record of atrial fibrillation. Patients were divided into 2 groups: ASP with ultrasound-assisted X-ray (ultrasound group, n=123), ASP under X-ray alone (X-ray group, n=118). Clinical features of patients including age, sex, percent of paroxysmal atrial fibrillation, and repeat ablation, CHA2DS2-VASc score and past history (hypertension, diabetes mellitus, coronary artery disease, stroke/transient ischemic attack (TIA), valve diseases) and echocardiographic parameters (left atrial dimension, left ventricular ejection fraction, left ventricular end-diastolic dimension) were obtained and compared. The first-pass rate, radiation exposure time, duration of ASP, and complications of ASP were also compared between the two groups. Results: The age of patients in this cohort was (62.5±8.0) years, and the proportion of males was 57.0% (n=138). Among them, the proportion of paroxysmal atrial fibrillation was 56.0% (n=135), and the ratio of repeat ablation was 17.8% (n=43). Age, sex, percent of paroxysmal atrial fibrillation, history of hypertension, diabetes mellitus were similar between the two groups. The first-pass rate was significantly higher in the ultrasound group than in the X-ray group (94.3% (116/123) vs. 79.7% (94/118), P=0.001); the exposure time of X-ray was significantly shorter in the ultrasound group than in the X-ray group ((31.3±7.9) s vs. (124.8±35.7) s, P<0.001), while the duration of ASP was longer in the ultrasound group ((10.1±1.8) minutes vs. (8.2±1.3) minutes, P<0.001). In terms of complications, the incidence of puncture into the pericardium was lower in the ultrasound group (0 vs.3.4% (4/118), P=0.039); the rate of transient ST-segment elevation post ASP was similar between the ultrasound group and X-ray group (2.4% (3/123) vs. 1.7% (2/118), P=0.999). Conclusion: Intracardiac ultrasound-assisted atrial septal puncture can effectively improve the accuracy of atrial septal puncture, shorten the radiation exposure time, and reduce the complications related to atrial septal puncture.

Causes of death and influencing factors of atrial fibrillation patients undergoing anticoagulation therapy / 中华心血管病杂志

Objective: To investigate the causes of death and predictors in patients with nonvalvular atrial fibrillation (AF) undergoing anticoagulation therapy. Methods: Consecutive anticoagulated nonvalvular AF patients were recruited from the China Atrial Fibrillation Registry (China-AF) Study from August 2011 to December 2018. After exclusion of patients with hypertrophic cardiomyopathy, dilated cardiomyopathy, or loss of follow-up within 1 year, 2 248 patients were included in this analysis. Enrolled patients were followed up were followed up for 3 and 6 months, and then every 6 months. The primary endpoint was death, including cardiovascular death, non-cardiovascular death and undetermined death. The patients were divided into survival group and death group according to the survival status after follow-up. Clinical information such as age and sex was collected. Cox proportional hazards regression was performed to identify associated risk factors for all-cause mortality, and Fine-Gray competing risk model was used to identify associated risk factors for cardiovascular mortality. Results: A total of 2 248 patients with atrial fibrillation receiving anticoagulant therapy died over a mean follow-up of (42±24) months, mean age was (67±10) years old and 41.1% (923/2 248) patients were female. The mortality rate was 2.8 deaths per 100 patient-years. The most common cause of death was cardiovascular deaths, accounted for 55.0% (120/218). Worsening heart failure was the most common cause of cardiovascular deaths (18.3% (40/218)), followed by bleeding events (12.9% (28/218)) and ischemic stroke (8.7% (19/218)). Multivariate Cox regression analysis showed that age (HR = 1.05, 95%CI 1.04-1.07, P<0.001), anemia (HR = 1.81, 95%CI 1.02-3.18, P = 0.041), heart failure (HR=2.40, 95%CI 1.75-3.30, P<0.001), ischemic stroke/transient ischemic attack (TIA)(HR = 1.59, 95%CI 1.21-2.13, P = 0.001) and myocardial infarction (HR = 2.93, 95%CI 1.79-4.81, P<0.001) were independently associated with all-cause death. Fine-Gray competing risk model showed that age (HR=1.05, 95%CI 1.02-1.08, P<0.001), heart failure (HR=2.81, 95%CI 1.79-4.39, P<0.001), ischemic stroke/TIA (HR=1.50, 95%CI 1.02-2.22, P=0.041) and myocardial infarction (HR=3.31, 95%CI 1.72-6.37, P<0.001) were independently associated with cardiovascular death. Conclusions: In anticoagulated nonvalvular AF patients, ischemic stroke represents only a small subset of deaths, whereas worsening heart failure is the most common cause of cardiovascular deaths. Heart failure, ischemic stroke/TIA, and myocardial infarction are associated with increased mortality.

Efficacy and safety of catheter ablation in patients with new-onset atrial arrhythmia after surgical excision of left atrial myxoma / 中华心血管病杂志

Objective: To evaluate the safety and efficacy of catheter ablation in patients with new-onset atrial arrhythmia after surgical excision of left atrial myxoma. Methods: Nine patients with new onset atrial arrhythmia and a prior history of left atrial myxoma, who received surgical myxoma excision and catheter ablation between September 2014 and November 2019, were included in the present study. Baseline characteristics, procedural parameters during catheter ablation, severe perioperative adverse events, recurrence rate of arrhythmia and clinical prognosis were analyzed. Kaplan Meier survival analysis was used to define the maintenance rate of sinus rhythm after catheter ablation in this patient cohort. Results: Nine patients were included. The average age was (55.8 ± 9.1) years old (3 male), there were 3 patients (3/9) with paroxysmal atrial fibrillation (PAF) and 6 patients (6/9) with atrial flutter or atrial tachycardia (AFL or AT). Ablation was successful in all patients, there were no perioperative complications such as stroke, pericardial effusion, cardiac tamponade, vascular complications or massive hemorrhage. During a mean follow-up time of 40.0 (27.5, 55.5) months, sinus rhythm was maintained in six patients (6/9) after the initial catheter ablation. The overall sinus rhythm maintenance rate was 2/3. In addition, 1 out of the 3 AF patients (1/3) developed recurrence of AF at 3 month after ablation, and 2 out of the 6 AFL or AT patients (2/6) developed late recurrence of AF or AFL (19 months and 29 months after ablation), two out of three patients with recurrent AFs or AFL received repeated catheter ablation and one patient remained sinus rhythm post repeat ablation. Meanwhile, there was no recurrence of atrial myxoma, no death, stroke, acute myocardial infarction and other events during the entire follow-up period. Conclusions: Catheter ablation is a safe and feasible therapeutic option for patients with new-onset atrial arrhythmia after surgical excision of left atrial myxoma.

The thromboembolism risk of low-risk atrial fibrillation patients with different clinical characteristics / 中华心血管病杂志

Objective: This study explored the thromboembolism risk of low-risk atrial fibrillation (AF) patients (CHA2DS2-VASc score of 0 or 1 for male and 1 or 2 for female) with different clinical characteristics to provide the basis for anticoagulation decision-making in these patients. Methods: We prospectively enrolled consecutive 2 862 nonvalvular low-risk AF patients between August 2011 to December 2018 in China-AF (China Atrial Fibrillation Registry) Study, their CHA2DS2-VASc score was 0 or 1 for male and 1 or 2 for female. According to their age, sex, presence or absence of hypertension, diabetes mellitus, congestive heart failure, and vascular disease at the time of enrolling, patients were divided into CHA2DS2-VASc score 0 score group, 1 score group, and 2 score group. Patients were followed up every 6 months by outpatient clinic visit or telephone interview. The outcome was a thromboembolic event, including ischemic stroke and systemic embolism. Univariate Cox regression analysis was used to compare the thromboembolism risk between the patients with different risk factors and CHA2DS2-VASc score 0 group. Results: A total of 2 862 low-risk atrial fibrillation patients were enrolled in this study. 915 patients (32.0%) were female, and age was (55.0±10.7) years old. There were 933 patients (32.6%) in CHA2DS2-VASc score 0 group, 1 401 patients (49.0%) in score 1 group and 528 patients (18.5%) in score 2 group. During follow-up (median 1.5 years, 5 811.82 person-years), 33 cases of thromboembolic events were recorded, the annual rate of thromboembolism was 0.57% (95%CI 0.40%~0.80%). The number of thromboembolic events in patients with CHA2DS2-VASc score 0, 1 and 2 were 8, 11 and 14, respectively, and the annual thromboembolism event rates were 0.40% (95%CI 0.20%-0.81%), 0.39% (95%CI 0.22%-0.71%) and 1.34% (95%CI 0.80%-2.27%), respectively. The risk of thromboembolism of CHA2DS2-VASc score 2 group (HR=3.53, 95%CI 1.48-8.44; P=0.005), especially female patients aged 65-74 years in CHA2DS2-VASc score 2 group (HR=2.67, 95%CI 1.63-4.38; P<0.000) was significantly higher than that in patients of CHA2DS2-VASc score 0 group. Conclusion: Low-Risk Atrial Fibrillation patients with CHA2DS2-VASc score 2, especially female patients aged 65-74 years old with CHA2DS2-VASc score 2 are at higher risk of thromboembolism in low-risk AF patients. For such patients, intensified oral anticoagulant therapy might be helpful to reduce the risk of thrombolism.

Whether Warfarin Therapy is Associated with Damage on Renal Function in Chinese Patients with Nonvalvular Atrial Fibrillation / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Warfarin is the most common oral anticoagulant to decrease the stroke risk associated with atrial fibrillation (AF). There are very few prospective studies that have explored whether warfarin has an association with damage on renal function in Chinese patients with nonvalvular AF (NVAF). The aim of this study was to evaluate the effects of warfarin on renal function and study the factors associated with kidney dysfunction in Chinese adult NVAF patients without dialysis therapy.</p><p><b>METHODS</b>From January 2011 to December 2013, a total of 951 NVAF patients from 18 hospitals were enrolled. The estimated glomerular filtration rate (eGFR) was calculated from baseline and follow-up serum creatinine levels. Kaplan-Meier survival curves compared the survival of a ≥25% decline in eGFR (hereafter, endpoint), while Cox models estimated hazard ratios (HR s) and 95% confidence intervals for this event after adjustment for age, gender, and selected potential risk factors for renal dysfunction. Cox regression analysis of the various clinical potential variables was performed to identify the predictors of a ≥25% decline in eGFR.</p><p><b>RESULTS</b>After a 58-month follow-up, 951 NVAF patients were divided by observation into warfarin (n = 655) and no anticoagulation groups (n = 296) and 120 (12.6%) patients experienced renal endpoint. Kaplan-Meier survival curves showed that the survival period was not different in the two groups (χ2 = 0.178, log-rank P= 0.67), but patients with systolic blood pressure (SBP) <140 mmHg have significant difference with patients with SBP ≥140 mmHg (χ2 = 4.903, log-rank P= 0.03). Multivariate Cox regression analysis revealed baseline eGFR and SBP as independent predictors of the endpoint, with HR s of 1.00, and 1.02, respectively.</p><p><b>CONCLUSION</b>In patients with NVAF, eGFR and SBP are associated with the deterioration of kidney function while Warfarin is not the risk factor of the ≥25% decline in eGFR.</p><p><b>TRIAL REGISTRATION</b>Chinese Clinical Trial Registry (No. ChiCTR-OCH-13003729); http://www.chictr.org.cn/showproj.aspx?proj = 5831.</p>

Impact of the origin of sinus node artery on recurrence after pulmonary vein isolation in patients with paroxysmal atrial fibrillation / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Major atrial coronary arteries, including the sinus node artery (SNA), were commonly found in the areas involved in atrial fibrillation (AF) ablation and could cause difficulties in achieving linear block at the left atrial (LA) roof. The SNA is a major atrial coronary artery of the atrial coronary circulation. This study aimed to determine impact of the origin of SNA on recurrence of AF after pulmonary vein isolation (PVI) in patients with paroxysmal AF.</p><p><b>METHODS</b>Seventy-eight patients underwent coronary angiography for suspected coronary heart disease, followed by catheter ablation for paroxysmal AF. According to the origin of SNA from angiographic findings, they were divided into right SNA group (SNA originating from the right coronary artery) and left SNA group (SNA originating from the left circumflex artery). Guided by an electroanatomic mapping system, circumferential pulmonary vein ablation (CPVA) was performed in both groups and PVI was the procedural endpoint. All patients were followed up at 1, 3, 6, 9 and 12 months post-ablation. Recurrence was defined as any episode of atrial tachyarrhythmias (ATAs), including AF, atrial flutter or atrial tachycardia, that lasted longer than 30 seconds after a blanking period of 3 months.</p><p><b>RESULTS</b>The SNA originated from the right coronary artery in 34 patients (43.6%) and the left circumflex artery in 44 patients (56.4%). Freedom from AF and antiarrhythmic drugs (AADs) at 1 year was 67.9% (53/78) for all patients. After 1 year follow-up, 79.4% (27/34) in right SNA group and 59.1% (26/44) in left SNA group (P = 0.042) were in sinus rhythm. On multivariate analysis, left atrium size (HR = 1.451, 95%CI: 1.240 - 1.697, P < 0.001) and a left SNA (HR = 6.22, 95%CI: 2.01 - 19.25, P = 0.002) were the independent predictors of AF recurrence.</p><p><b>CONCLUSIONS</b>The left SNA is more frequent in the patients with paroxysmal AF. After one year follow-up, the presence of a left SNA was identified as an independent predictor of AF recurrence after CPVA in paroxysmal AF.</p>

Serum uric acid levels correlate with recurrence of paroxysmal atrial fibrillation after catheter ablation / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Recently there has been a great deal of interest in the role of serum uric acid (SUA) in atrial fibrillation (AF). The objective of this study was to establish whether there is a relationship between levels of SUA and recurrence of paroxysmal AF after catheter ablation.</p><p><b>METHODS</b>Three hundred and thirty patients diagnosed with paroxysmal AF were analyzed. Patients were categorized into quartiles on the basis of their pre-operative SUA measurement and follow-up, and Kaplan-Meier estimation with a Log-rank test was used for the analysis of the influence of SUA on the recurrence of AF. Pre-procedural clinical variables were correlated with the clinical outcome after ablation using multivariate Logistic analysis. A Cox proportional hazards model was used to estimate the relationship between SUA and the recurrence of AF.</p><p><b>RESULTS</b>After a mean follow-up of (9.341 ± 3.667) (range 3.0 - 16.3) months, recurrence rates from the lowest SUA quartile to the highest SUA quartile were 16.0%, 26.4%, 28.3%, and 29.3% respectively (P = 0.014). After adjustment for gender, body mass index (BMI), hypertension, serum levels of high sensitivity C-reactive protein (hsCRP), triglyceride (TG), left atrial diameter (LA), estimated glomerular filtration rate (eGFR), and SUA, there was an increased risk of recurrence in subjects in the highest SUA quartile compared with those in the lowest quartile (hazard ratio 2.804, 95% confidence interval 1.466 - 5.362, P = 0.002). Following multivariate Logistical analysis, SUA was found to be an independent predictor of recurrence (hazard ratio 1.613, 95% confidence interval 1.601 - 1.625, P = 0.014).</p><p><b>CONCLUSION</b>In a retrospective study of patients with paroxysmal AF undergoing catheter ablation, elevated preoperative SUA levels were associated with a higher rate of recurrence of AF.</p>

Outcome of catheter ablation of atrial fibrillation in patients with prior ischemic stroke / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Catheter ablation for atrial fibrillation (AF) has been demonstrated to be effective in a subsets of patients with AF. However, very few data are available in regard to patients with prior history of stroke undergoing catheter ablation. This study aimed to investigate the outcome of catheter ablation in AF patients with prior ischemic stroke.</p><p><b>METHODS</b>Between January 2008 and December 2011, of 1897 consecutive patients who presented at Beijing An Zhen Hospital for treatment of drug-refractory AF, 172 (9.1%) patients in the study population had a history of ischemic stroke. All patients underwent catheter ablation and were followed up to assess maintenance of sinus rhythm and recurrence of symptomatic stroke.</p><p><b>RESULTS</b>Among these 1897 patients, 1768 (93.2%) who had complete follow-up information for a minimum of six months were included in the final analysis. Patients in the stroke group (group I) and the no-stroke group (group II) were similar in regards to gender, body mass index (BMI), history of diabetes, type of AF, and left atrial size. The patients in group I were older than those in group II, and had a higher incidence of hypertension, chronic heart failure, lower left ventricular ejection fraction (LVEF), and higher CHADS2 scores. Six months after ablation, 107 (68.6%) patients in group I and 1403 (87.1%) in group II had discontinued warfarin treatment (P < 0.001). During a median follow-up of (633 ± 415) days, 65 patients in the group I and 638 in group II experienced AF recurrence, and five patients in group I and 28 in group II developed symptomatic stroke. The rates of AF recurrence and recurrent stroke were similar between group I and group II (41.7% vs. 39.6%, P = 0.611; 3.2% vs. 1.7%, P = 0.219; respectively).</p><p><b>CONCLUSION</b>Catheter ablation of AF in patients with prior stroke is feasible and efficient.</p>

Transient ST-segment elevation after transseptal puncture for atrial fibrillation ablation in two cases / 中华医学杂志(英文版)

The present report demonstrates two cases of transient inferior ST-segment elevation accompanied by profound hypotension and bradycardia immediately after transseptal puncture for catheter ablation of atrial fibrillation. This rare complication of transseptal puncture was resolved quickly within several minutes. The most likely mechanism of this phenomenon is coronary vasospasm, although coronary embolism can not be ruled out completely. This complication is characterized as follows: (1) The right coronary artery might be the most likely involved vessel and therefore myocardial ischemia usually occurs in the inferior wall of left ventricular; (2) Reflex hypotension and bradycardia by the Bezold-Jarisch reflex secondary to inferior ischemia often occur at the same time. Though it appears to be a transient and completely reversible phenomenon, there are still potential life-threatening risks because of myocardial ischemia and profound haemodynamic instability. Clinical cardiologists should be aware of this rare complication and properly deal with it.

Catheter ablation of persistent atrial fibrillation with and without a history of paroxysmal atrial fibrillation / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>It is unclear whether a history of paroxysmal atrial fibrillation (PAF) would impact the effect of catheter ablation on persistent atrial fibrillation (AF). This study aimed to compare the effect of catheter ablation on persistent AF with and without a history of PAF.</p><p><b>METHODS</b>One hundred and eighty-three patients underwent catheter ablation of persistent AF lasting for > 1 month and were reviewed. Patients were divided into two groups according to whether they had a history of PAF or not. Group I consisted of persistent AF patients with a history of PAF, and group II consisted of persistent AF patients without such a history. All patients received catheter ablation focused on pulmonary vein isolation and were observed for arrhythmia recurrences, which were defined as documented episodes of AF or atrial tachycardia after a blanking period of 3 months.</p><p><b>RESULTS</b>One hundred and three patients (60.9%) in group I and sixty-six patients (39.1%) in group II were successfully followed and included in analysis. There were no significant differences in clinical and echocardiographic characteristics between both groups except for a younger age and more male patients in group II. After (15.5 ± 10.7) months of follow-up, 59 (57.3%) patients in group I and 49 (74.2%) patients in group II maintained sinus rhythm free of anti-arrhythmia drugs (P = 0.025). Multivariate analyses found left atrial anteroposterior diameter (P = 0.006) and persistent AF with a history of PAF (OR 1.792, 95%CI 1.019 - 3.152; P = 0.043) as the only independent statistical predictors of arrhythmia recurrences.</p><p><b>CONCLUSION</b>The arrhythmia recurrence rate of catheter ablation based on pulmonary vein isolation in persistent AF with a history of PAF was higher than those without a history of PAF.</p>

Impact of different termination modes on atrial fibrillation termination in catheter ablation of persistent atrial fibrillation / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The optimal endpoint for catheter ablation of persistent atrial fibrillation (AF) remains ambiguous. This study investigated the impact of AF termination as a procedural endpoint and the termination mode on long-term clinical outcome.</p><p><b>METHODS</b>Two hundred and ninety-three patients who underwent stepwise ablation for persistent AF were categorized into the AF termination by ablation group and into the electrical cardioversion (CV) group. Subgroups were also analyzed based on different termination modes. Follow-up assessment included early recurrence and sinus rhythm (SR) maintenance.</p><p><b>RESULTS</b>During initial ablation, 33 patients (11.3%) were directly converted to SR, 166 patients (56.7%) were converted to atrial tachycardia (AT) that subsequently restored SR with further ablation in 98 patients (33.4%), and a total of 162 patients (55.3%) underwent cardioversion due to persistent atrial arrhythmias. Comparison between termination by ablation and termination by cardioversion in patients exhibiting AF or AT revealed that no significant difference was observed in early recurrence (38.2% vs. 43.8%, P = 0.328) and SR maintenance (67.2% vs. 59.8%, P = 0.198) during the (23 ± 7) months follow-up. Even after repeat ablation, the SR maintenance continued to exhibit no statistical difference in above two groups (72.5% vs. 70.4%, P = 0.686). Further analysis of subgroups, however, demonstrated that patients with AF terminated directly to SR experienced better clinical outcomes than other subgroups (P < 0.05). Furthermore, atrial arrhythmias present during ablation have been implicated in prediction of recurrence mode: AF or AT (P < 0.05).</p><p><b>CONCLUSIONS</b>Termination as a procedural endpoint is not associated with favorable long-term SR maintenance in persistent AF. AF methods that convert arrhythmia directly to SR have, however, been linked with improved clinical outcomes, although conversions to AT may not be correlated. Atrial arrhythmias observed during the ablation may be used to predict the recurrence mode.</p>

Efficacy of catheter ablation of atrial fibrillation beyond HATCH score / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>HATCH score is an established predictor of progression from paroxysmal to persistent atrial fibrillation (AF). The purpose of this study was to determine if HATCH score could predict recurrence after catheter ablation of AF.</p><p><b>METHODS</b>The data of 488 consecutive paroxysmal AF patients who underwent an index circumferential pulmonary veins (PV) ablation were retrospectively analyzed. Of these patients, 250 (51.2%) patients had HATCH score = 0, 185 (37.9%) patients had HATCH score = 1, and 53 (10.9%) patients had HATCH score ≥ 2 (28 patients had HATCH score = 2, 23 patients had HATCH score = 3, and 2 patients had HATCH score = 4).</p><p><b>RESULTS</b>The patients with HATCH score ≥ 2 had significantly larger left atrium size, the largest left ventricular end systolic diameter, and the lowest ejection fraction. After a mean follow-up of (823 ± 532) days, the recurrence rates were 36.4%, 37.8% and 28.3% from the HATCH score = 0, HATCH score = 1 to HATCH score ≥ 2 categories (P = 0.498). Univariate analysis revealed that left atrium size, body mass index, and failure of PV isolation were predictors of AF recurrence. After adjustment for body mass index, left atrial size and PV isolation, the HATCH score was not an independent predictor of recurrence (HR = 0.92, 95% confidence interval = 0.76 - 1.12, P = 0.406) in multivariate analysis.</p><p><b>CONCLUSION</b>HATCH score has no value in prediction of AF recurrence after catheter ablation.</p>

Epicardial isolation of pulmonary veins with ethanol in open chest dogs / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Radiofrequency (RF) ablation has become a widely accepted treatment for atrial fibrillation (AF). This study aimed to identify the efficacy and safety of pulmonary vein (PV) ablation with ethanol and to explore an alternative energy source for catheter ablation of AF.</p><p><b>METHODS</b>Twelve open-chest mongrel dogs were randomized into ethanol ablation group and control group. Both the injections and electrophysiological mapping procedures were performed epicardialy. In ethanol ablation group (n = 6), injections were performed to circumferentially ablate the root of each PV (0.2 ml each site, 3 mm apart) with 95% ethanol using an 1 ml injector. In control group (n = 6), saline was injected other than ethanol. PV isolation was confirmed with a circular catheter immediately after the procedure and at follow up of 30 days. PV isolation was defined as the absence of PV potentials at each electrode of the circular catheter positioned at the PV side of the lesions, as well as complete conduction block into left atrium (LA) during PV pacing.</p><p><b>RESULTS</b>PV electrical isolation with complete bidirectional conduction block was achieved with ethanol immediately and at 30 days in 95% of PVs, while saline injection caused only transient conduction changes between LA and PVs. In ethanol group, histologic analysis showed transmural lesions at 30 days. And there was no evidence of PV stenosis or thrombus formation. Mean LA diameter was not significantly different between baseline and 30 days.</p><p><b>CONCLUSION</b>Ethanol is a safe energy source to effectively isolate PV in canine model and may be promising in endocardial ablation procedure of AF patients in the future.</p>

Cigarette smoking inhibits the anti-platelet activity of aspirin in patients with coronary heart disease / 中华医学杂志(英文版)

<p><b>OBJECTIVE</b>Tobacco smoking results in increased platelet aggregability, which suggests that low-dose aspirin used in common clinical practice may not effectively inhibit platelet activity in smokers with coronary heart disease (CHD). This review was performed to assess the effect of aspirin on platelet aggregation in patients with CHD.</p><p><b>DATA SOURCES</b>We performed an electronic literature search of MEDLINE (starting from the beginning to March 15, 2009) using the term "smoking" or "tobacco" paired with the following: "platelet", "aspirin" or "coronary heart disease".</p><p><b>STUDY SELECTION</b>We looked for review articles regarding the effect of tobacco smoking on platelet activity and on the anti-platelet efficacy of aspirin in healthy people and patients with CHD. The search was limited in "core clinical journal". In total, 1321 relevant articles were retrieved, and 36 articles were ultimately cited.</p><p><b>RESULTS</b>Tobacco smoking results in increased platelet aggregability, which can be inhibited by low-dose aspirin in the healthy population. However, in patients with CHD, the increased platelet aggregability can not be effectively inhibited by the same low-dose of aspirin. A recent study indicated that clopidogrel or an increased dose of aspirin can effectively inhibit the increased platelet aggregability induced by tobacco smoking in patients with CHD.</p><p><b>CONCLUSIONS</b>It is important for patients with CHD to quit smoking. For the current smoker, it may be necessary to take larger doses of aspirin than normal or take an adenosine diphosphate receptor inhibitor along with aspirin to effectively inhibit the increased platelet activity.</p>

Mechanisms of organized atrial tachycardia during catheter ablation of chronic atrial fibrillation by stepwise approach / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Extensive atrial fibrillation (AF) ablation is associated with an increased success rate of catheter ablation in chronic AF patients and an increased rate of atrial tachycardia (AT) during the procedure. The mechanism of these ATs varies in previous studies. Our study aimed to report the mechanism of organized AT occurring during the stepwise ablation procedure of chronic AF.</p><p><b>METHODS</b>A prospective cohort of 86 consecutive patients who underwent an ablation procedure for chronic atrial fibrillation (CAF) was investigated. The stepwise procedure was performed in the following order: circumferential pulmonary vein ablation, complex fractionated atrial electrograms ablation, mapping and ablation of AT. The endpoint was noninducibility of AF/AT after sinus rhythm (SR) was restored or the procedure time was beyond 6 hours.</p><p><b>RESULTS</b>Sixty-nine (80%) of patients converted to SR via AT. A total of 179 sustained ATs were observed in 69 patients during the procedure. There were 81% (n = 145) macroreentrant ATs which included 65 perimitral circuits, 48 peritricuspid tachycardia and 32 roof dependent circuits, 12% (n = 21) localized reentrant and 7% (n = 13) focal ATs. Thirty (15%) patients experienced significant left atrium (LA) and LA appendage (LAA) conduction delay or dissociation in the procedure or during the follow-up period.</p><p><b>CONCLUSIONS</b>Most CAF patients converted to SR via ablation of organized AT occurring during the stepwise procedure. The mechanism of most of these ATs was macro-reentry.</p>

Metabolic syndrome in patients with atrial fibrillation in the absence of structural heart disease from a tertiary hospital in China / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Metabolic syndrome (MetS) and atrial fibrillation (AF) are causally related. This study aimed to determine the prevalence of MetS in patients with AF in the absence of structural heart disease from a tertiary hospital in China.</p><p><b>METHODS</b>In a single center, 741 inpatients with AF in the absence of structural heart disease prior to catheter ablation were retrospectively reviewed. Among them, 588 (79.4%) patients had paroxysmal AF. Subgroup analyses were performed in paroxysmal AF and persistent/permanent AF.</p><p><b>RESULTS</b>MetS was found in 343 (46.3%) patients (200 males, 143 females); 0, 1, 2, 3, 4, 5 components of the MetS were found in 59 (8.0%), 140 (18.9%), 199 (26.9%), 203 (27.4%), 103 (13.9%) and 37 (5.0%) patients, respectively. The prevalences of overweight/obesity, high blood pressure, high glucose level, high triglyceride level and low high density lipoproteins cholesterol level were 53.8%, 47.6%, 23.2%, 40.6% and 72.1%, respectively. The prevalence of MetS was not significantly different between the paroxysmal AF group and the persistent/permanent AF group (44.6% vs 52.9%, P = 0.064). The five components of MetS except overweight/obesity (69.3% vs 49.8%, P < 0.001) were not significantly different between the aforementioned two groups. The left atrium diameter increased with the sum of the MetS components. The left atrium diameter in the MetS group was significantly higher than that in the non-MetS group both in patients with paroxysmal AF and in patients with persistent/permanent AF.</p><p><b>CONCLUSIONS</b>The prevalence of MetS in patients with AF prior to catheter ablation is high. Further study and prevention are needed.</p>

Clinical efficacy of irbesartan and amiodarone in elderly patients with paroxysmal atrial fibrillation / 中南大学学报(医学版)

OBJECTIVE@#To investigate the effect of combination of irbesartan and amiodarone in elderly patients with paroxysmal atrial fibrillation.@*METHODS@#Ninety-one patients with paroxysmal atrial fibrillation were randomly divided into 2 groups: Group I (amiodarone group, n=45) and Group II (amiodarone plus Irbesartan group, n=46).After 18 month follow-up, the maintenance rate of sinus rhythm was measured in the 3rd, 6th, 9th, 12th, and 18th months, and the left atrial diameter (LAD) was measured before the treatment and 6th, 12th, and 18th months after the treatment.@*RESULTS@#There was no difference in the maintenance rate of sinus rhythm between Group I and Group II in the 3rd month. The maintenance rate of sinus rhythm in Group I was 72.1%, 65.1%, 60.5%, and 55.8% in the 6th, 9th, 12th, and 18th months, and the rate in the Group II was 88.6%, 86.4%, 81.8%, and 79.5%. They both had significant difference (P<0.05). At 12 months after the treatment, LAD in Group I was significantly larger than that of Group II (P<0.05).@*CONCLUSION@#The combination of irbesartan and amiodarone is more effective than amiodarone alone for sinus rhythm maintenance, and may restrain the enlargement of the left atrium.

Pulmonary vein tachycardia after pulmonary vein isolation in patients with atrial fibrillation / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Pulmonary vein (PV) isolation has been developed to treat patients with atrial fibrillation (AF), and the electrophysiological endpoint of PV isolation is the disappearance or dissociation of pulmonary vein potentials (PVPs). Pulmonary vein tachycardia (PVT) is the dissociated PV rhythm with a rapid rate. However, the characteristics and significance of PVT after pulmonary vein isolation in patients with AF remains unclear.</p><p><b>METHODS</b>From June 2003 to June 2005, a total of 285 consecutive patients with drug refractory AF were included in this study, and they underwent segmental pulmonary vein ablation (SPVA) or circumferential pulmonary vein ablation (CPVA). PV isolation was the initial endpoint for both approaches with documenting disappearance or dissociation of PVPs. PVT was characterized as dissociated activities within PVs with a circle length (CL) of < 300 ms, and was classified into organized PVT or disorganized PVT according to the variance of CL. Systematic follow-up was conducted after initial procedures. Continuous variables were analyzed by Student's t test and categorical variables were analyzed by chi-square test.</p><p><b>RESULTS</b>Three hundred and fifteen PVs were ablated in 85 patients underwent SPVA approach, 400 circular lesions surrounding ipsilateral PVs (including 790 PVs) were produced in the rest of 200 patients received CPVA approach. Electrical isolation was achieved in all of these PVs. Of these, PVPs were abolished in 89.8% (992/1105) of the ablated PVs, dissociated PV rhythms were documented in the rest 10.2 % (113/1105) of the treated PVs. Among the 113 dissociated PV rhythms, 28 met the criteria of PVT with mean CL of (155 +/- 43) ms (2 PVTs in 2 patients received SPVA, 26 PVTs in 18 patients underwent CPVA). PVT was more frequently documented in patients underwent CPVA approach [9.0% (18/200) vs 2.3% (2/85), P = 0.04]. During the 6-month follow-up, it was indicated that no significant difference existed in AF free rate between patients with PVT and those without PVT (P = 0.75).</p><p><b>CONCLUSIONS</b>PVT dissociated from LA activations can be documented after PV isolation, especially in patients underwent CPVA approach. However, PVT does not affect the follow-up results.</p>