Combined epicardial and endocardial approach for redo radiofrequency catheter ablation in patients with persistent atrial fibrillation: a randomized clinical trial.

AIMS: An epicardial approach is an effective means to detect and eliminate residual potentials in non-transmural lesions created during prior endocardial ablation. We sought to determine the impact of a combined epicardial and endocardial approach compared with a conventional endocardial approach, on recurrence-free survival after redo ablation. METHODS AND RESULTS: Participants with recurred persistent atrial fibrillation after prior endocardial ablation were randomized (1:1) to undergo treatment with the combined approach (epicardial followed by endocardial ablation) for the treatment group or conventional approach (endocardial ablation only) for the control group. The primary outcome was the time to recurrence of atrial fibrillation or atrial tachycardia following a 90-day blanking period within 12 months after the procedure. The secondary safety outcome was the occurrence of procedure-related complications within 24 h after the procedure. Of 100 randomized participants {median age, 59.0 [(interquartile range (IQR): 53.8-64.3] years, including 16% women, with one prior ablation (IQR: 1-1)}, 93 (93%) completed the trial. Events relevant to the primary outcome occurred in 16 patients in the treatment group and in 21 patients in the control group {Kaplan-Meier estimator percentages, 32 vs. 42%; hazard ratio, 0.71 [95% confidence interval (CI): 0.37-1.37]}. The periprocedural complication rate was lower in the treatment group [2 vs. 16%; odds ratio, 0.11 (95% CI: 0.00-0.87)] with similar achievement of the procedural endpoint in the two groups. CONCLUSION: In the redo procedure for persistent atrial fibrillation, the combined approach had no significant difference of recurrence-free survival and a lower procedural complication rate compared with the conventional approach.

Frequent drinking is a more important risk factor for new-onset atrial fibrillation than binge drinking: a nationwide population-based study.

AIMS: Heavy consumption of alcohol is a known risk factor for new-onset atrial fibrillation (AF). We aimed to evaluate the relative importance of frequent drinking vs. binge drinking. METHODS AND RESULTS: A total of 9 776 956 patients without AF who participated in a national health check-up programme were included in the analysis. The influence of drinking frequency (day per week), alcohol consumption per drinking session (grams per session), and alcohol consumption per week were studied. Compared with patients who drink twice per week (reference group), patients who drink once per week showed the lowest risk [hazard ratio (HR) 0.933, 95% confidence interval (CI) 0.916-0.950] and those who drink everyday had the highest risk for new-onset AF (HR 1.412, 95% CI 1.373-1.453), respectively. However, the amount of alcohol intake per drinking session did not present any clear association with new-onset AF. Regardless of whether weekly alcohol intake exceeded 210 g, the frequency of drinking was significantly associated with the risk of new-onset AF. In contrast, when patients were stratified by weekly alcohol intake (210 g per week), those who drink large amounts of alcohol per drinking session showed a lower risk of new-onset AF. CONCLUSION: Frequent drinking and amount of alcohol consumption per week were significant risk factors for new-onset AF, whereas the amount of alcohol consumed per each drinking session was not an independent risk factor. Avoiding the habit of consuming a low but frequent amount of alcohol might therefore be important to prevent AF.

The impact of body weight and diabetes on new-onset atrial fibrillation: a nationwide population based study.

BACKGROUND: Being obese or underweight, and having diabetes are important risk factors for new-onset atrial fibrillation (AF). However, it is unclear whether there is any interaction between body weight and diabetes in regard to development of new-onset AF. We aimed to evaluate the role of body weight status and various stage of diabetes on new-onset AF. METHODS: This was a nationwide population based study using National Health Insurance Service (NHIS) data. A total of 9,797,418 patients who underwent national health check-ups were analyzed. Patients were classified as underweight [body mass index (BMI) < 18.5], normal reference group (18.5 ≤ BMI < 23.0), upper normal (23.0 ≤ BMI < 25.0), overweight (25.0 ≤ BMI < 30.0), or obese (BMI ≥ 30.0) based on BMI. Diabetes were categorized as non-diabetic, impaired fasting glucose (IFG), new-onset diabetes, diabetes < 5 years, and diabetes ≥ 5 years. Primary outcome end point was new-onset AF. New-onset AF was defined as one inpatient or two outpatient records of International Classification of Disease, Tenth Revision (ICD-10) codes in patients without prior AF diagnosis. RESULTS: During 80,130,161 patient*years follow-up, a total of 196,136 new-onset AF occurred. Obese [hazard ration (HR) = 1.327], overweight (HR = 1.123), upper normal (HR = 1.040), and underweight (HR = 1.055) patients showed significantly increased risk of new-onset AF compared to the normal reference group. Gradual escalation in the risk of new-onset AF was observed along with advancing diabetic stage. Body weight status and diabetes were independently associated with new-onset AF and at the same time, had synergistic effects on the risk of new-onset AF with obese diabetic patients having the highest risk (HR = 1.823). CONCLUSIONS: Patients with obesity, overweight, underweight, and diabetes had significantly increased risk of new-onset AF. Body weight status and diabetes had synergistic effects on the risk of new-onset AF. The risk of new-onset AF increased gradually with advancing diabetic stage. This study suggests that maintaining optimal body weight and glucose homeostasis might prevent new-onset AF.

Cardiac arrest due to coronary vasospasm after sugammadex administration -a case report.

BACKGROUND: Sugammadex is a widely used medication for the reversal of aminosteroid neuromuscular blockades. Although sugammadex is generally regarded to be safe, concerns about the risk of serious complications have emerged. CASE: A 57-year-old man without a history of coronary disease was scheduled for general anesthesia to undergo cardiac radiofrequency catheter ablation due to symptomatic persistent atrial fibrillation and flutter. At the end of the procedure, he was given 400 mg of sugammadex. A little later, the electrocardiogram showed a sudden ST elevation on the inferior leads, followed by cardiac arrest. The urgent coronary angiography demonstrated total collapse of the right coronary artery. After two injections of intra-coronary nitroglycerin, the vasospasm of the right coronary artery was completely resolved. The patient recovered without sequelae and was discharged on postoperative day 5. CONCLUSIONS: Clinicians should pay close attention to the potential risk of coronary vasospasm, even cardiac arrest, after sugammadex administration.

Impact of angiotensin-converting enzyme inhibitors versus angiotensin receptor blockers on clinical outcomes in hypertensive patients with acute myocardial infarction.

There has been a concern that angiotensin receptor blockers (ARB) may increase myocardial infarction (MI) in hypertensive patients compared with other classes of anti-hypertensive drugs. Angiotensin-converting enzyme inhibitor (ACEI) is recommended as a first-line inhibitor of renin-angiotensin system (RASI) in patients with acute MI (AMI), but ARB is also frequently used to control blood pressure. This study investigated the association of ARB vs. ACEI with the long-term clinical outcomes in hypertensive patients with AMI. Among patients enrolled in the nationwide AMI database of South Korea, the KAMIR-NIH, 4,827 hypertensive patients, who survived the initial attack and were taking ARB or ACEI at discharge, were selected for this study. ARB therapy was associated with higher incidence of 2-year major adverse cardiac events, cardiac death, all-cause death, MI than ACEI therapy in entire cohort. After propensity score-matching, ARB therapy was still associated with higher incidence of 2-year cardiac death (hazard ratio [HR], 1.60; 95% confidence interval [CI], 1.20-2.14; P = 0.001), all-cause death (HR, 1.81; 95% CI, 1.44-2.28; P < 0.001), and MI (HR, 1.76; 95% CI, 1.25-2.46; P = 0.001) than the ACEI therapy. It was concluded that ARB therapy at discharge in hypertensive patients with AMI was inferior to ACEI therapy with regard to the incidence of CD, all-cause death, and MI at 2-year. These data suggested that ACEI be a more appropriate RASI than ARB to control BP in hypertensive patients with AMI.

Sex-Related Differences in Left Atrial Low-Voltage Areas According to CHA2DS2-VA Scores among Patients with Atrial Fibrillation.

(1) Background: We hypothesized that female sex would have a differential impact on left atrial (LA) low-voltage areas (LVAs) according to CHA2DS2-VA scores. (2) Methods: This study included 553 patients who underwent radiofrequency catheter ablation (RFCA) for atrial fibrillation (AF). LVAs were defined as regions with bipolar peak-to-peak voltages of <0.5 mV. The proportion of LVAs was calculated by dividing the total LVA by the LA surface area. (3) Results: There was no sex-related difference in LA LVAs among patients with a CHA2DS2-VA scores ≤ 2. The proportion of LVAs was significantly higher in females among patients with CHA2DS2-VA scores of 3 or 4 (10.1 (4.7−15.1)% vs. 15.8 (9.2−32.1)%; p = 0.027). Female sex was significantly associated with extensive LVAs (LVA proportion ≥ 30%). Females had odd ratios of 27.82 (95% confidence interval (CI) 3.33−756.8, p = 0.01), and 1.53 (95% CI 0.81−2.83, p = 0.184) for extensive LAVs in patients with CHA2DS2-VA scores ≥ 3 and CHA2DS2-VA scores < 3, respectively. In the multiple regression model, female patients with a CHA2DS2-VA ≥3 were significantly associated with a higher proportion of LVAs (ß = 8.52, p = 0.039). (4) Conclusions: Female sex was significantly associated with extensive LVAs, particularly when their CHA2DS2-VA scores were ≥3. This result suggests that female sex has a differential effect on the extent of LVAs based on the presence of additional risk factors.

Therapeutic implications of galectin-3 in patients with atrial fibrillation.

Atrial fibrosis can present as an arrhythmogenic substrate that is correlated with higher recurrence after catheter ablation for atrial fibrillation. Galectin-3, a beta-galactoside-binding lectin, is highly expressed and secreted from macrophages and is important in inflammation and fibrosis. We assessed the clinical implications of serum galectin-3 in patients with atrial fibrillation. This was a prospective cohort study of consecutive patients who underwent radiofrequency catheter ablation in a tertiary referral center from February 2017 to September 2017. Intracardiac blood sampling, echocardiographic measurements, magnetic resonance imaging with late gadolinium enhancement, electrophysiologic testing, and endocardial voltage mapping were consistently implemented in 75 patients before the ablation. Serum galectin-3 level was higher in patients with diabetes mellitus and was correlated with values that indicated the left atrial size. During a median 14 months of follow-up, atrial tachyarrhythmia recurred in 27% of patients. In multivariable Cox regression analysis, non-paroxysmal atrial fibrillation (hazard ratio 6.8; 95% confidence interval 1.6-28.9) and higher galectin-3 levels (hazard ratio 1.3; 95% confidence interval 1.0-1.7) were associated with increased risk of recurrence. Serum galectin-3 may be a prognostic biomarker for risk stratification in patients with atrial fibrillation planned catheter ablation.

Association of the medical therapy with beta-blockers or inhibitors of renin-angiotensin system with clinical outcomes in patients with mildly reduced left ventricular ejection fraction after acute myocardial infarction.

In the era of the initial optimal interventional and medical therapy for acute myocardial infarction (AMI), a number of patients with mildly reduced left ventricular ejection fraction (EF) (41%-49%) have been increasing. This observational study aimed to investigate the association between the medical therapy with oral beta-blockers or inhibitors of renin-angiotensin system (RAS) and 2-year clinical outcomes in patients with mildly reduced EF after AMI. Among patients enrolled in the Korea Acute Myocardial Infarction Registry-National Institute of Health, propensity-score matched patients who survived the initial attack and had mildly reduced EF were selected according to beta-blocker or RAS inhibitor therapy at discharge. Beta-blocker therapy at discharge was associated with lower 2-year major adverse cardiac events which was a composite of cardiac death, myocardial infarction, revascularization and re-hospitalization due to heart failure (8.7 vs 12.8/100 patient-years; hazard ratio [HR] 0.68; 95% confidence interval [CI] 0.50-0.93; P = .015), and no significant interaction between EF ≤ 45% and > 45% was observed (Pinteraction = 0.354). This association was mainly driven by lower myocardial infarction in patients with beta-blockers (HR 0.50; 95% CI 0.26-0.95; P = .035). Inhibitors of RAS at discharge were associated with lower re-hospitalization due to heart failure (1.8 vs 3.5/100 patient-years; HR 0.53; 95% CI 0.33-0.86; P = .010) without a significant interaction between EF ≤ 45% and > 45% (Pinteraction = 0.333). In patients with mildly reduced EF after AMI, the medical therapy with beta-blockers or RAS inhibitors at discharge was associated with better 2-year clinical outcomes.

Association of changes of pulse wave velocity and augmentation index after isometric handgrip exercise with coronary lesion extent and revascularization.

BACKGROUND: Arterial stiffness is associated with myocardial ischemia and incident coronary artery disease (CAD), and indexes of arterial stiffness are usually increased in patients with CAD. However, these indexes are often increased in elderly without CAD. Arterial stiffness in patients with CAD may become more evident after isometric handgrip exercise which increases systolic pressure and ventricular afterload. We investigated the association of the change of stiffness indexes after isometric handgrip exercise with the lesion extent of CAD and the necessity for coronary revascularization. METHODS: Patients who were scheduled a routine coronary angiography via a femoral artery were enrolled. Arterial waveforms were traced at aortic root and external iliac artery using coronary catheters at baseline and 3 min after handgrip exercise. Augmentation index (AIx) was measured on the recorded aortic pressure waveform, and pulse wave velocity (PWV) was calculated using the ECG-gated time difference of the upstroke of arterial waveforms and distance between aortic root and external iliac artery. RESULTS: Total 37 patients were evaluated. Both PWV and AIx increased after handgrip exercise. ΔPWV was significantly correlated with ΔAIx (r = 0.344, P = 0.037). Patients were divided into higher and lower ΔPWV or ΔAIx groups based on the median values of 0.4 m/sec and 3.3%, respectively. Patients with higher PWV had more 2- or 3-vessel CAD (69% vs. 27%, P = 0.034), and underwent percutaneous coronary intervention (PCI) more frequently (84% vs. 50%, P = 0.038), but higher ΔAIx was not associated with either the lesion extent or PCI. Area under curve (AUC) of ΔPWV in association with PCI by C-statistics was 0.70 (95% confidence interval [CI] 0.51-0.88; P = 0.056). In multiple logistic regression analysis, ΔPWV was significantly associated with PCI (odds ratio 7.78; 95% CI 1.26-48.02; P = 0.027). CONCLUSIONS: Higher ΔPWV after isometric handgrip exercise was associated with the lesion extent of CAD and the necessity for coronary revascularization, but higher ΔAIx was not.

Early Recurrence Is Reliable Predictor of Late Recurrence After Radiofrequency Catheter Ablation of Atrial Fibrillation.

OBJECTIVES: This study aimed to compare the risk of late recurrence in patients with and without early recurrence. BACKGROUND: Early recurrence of atrial fibrillation (AF) or atrial tachycardia (AT) after radiofrequency catheter ablation (RFCA) in AF patients is known to be a transient phenomenon. The theoretical basis of the blanking period is based on such observations. However, the clinical implications of early recurrence need further validation. METHODS: Consecutive RFCA cases in a tertiary hospital were analyzed. Early recurrence was defined as any AT or AF event occurring within 90-days post-RFCA. Early recurrence as AT and AF were also analyzed separately. RESULTS: A total of 3,120 patients underwent RFCA. Early recurrence occurred in 751 patients (24.1%). Patients who experienced early recurrence had a larger left atrium, worse hemodynamics in the left atrial appendage, and a higher prevalence of nonparoxysmal AF and heart failure. Among patients who experienced early recurrence, 69.6% of patients eventually had late recurrence. Early recurrence was associated with a 4.3- and 3.6-fold increase in the risk of late recurrence after single and multiple procedures, respectively. After multivariate adjustment, early recurrence was an independent risk factor for late recurrence with 3.6- and 2.8-fold increase in the risk of late recurrence after single and multiple procedures, respectively. Early recurrence AT had a lower risk of late recurrence compared with early recurrence AF. CONCLUSIONS: Early recurrence was a reliable predictor for late recurrence. The clinical significance of the blanking period in the current guidelines may need to be revisited.

A novel predictive model for late recurrence after catheter ablation for atrial fibrillation using left appendage volume measured by cardiac computed tomography.

Larger left atrial appendage (LAA) volume is associated with a higher risk of late recurrence (LR) in patients undergoing radiofrequency catheter ablation (RFCA) for atrial fibrillation (AF). However, it is unclear whether LAA volume predicts LR, independent of established risk factors. We sought to evaluate the value of LAA volume in predicting LR after RFCA for AF and to develop a score prediction model including LAA volume for these patients. We retrospectively studied 992 patients who underwent RFCA for AF and cardiac computed tomography before RFCA at a single center. At 3 years after RFCA, 362 patients (36.5 %) experienced recurrence. The multivariate Cox regression model showed that age ≥ 75 years (10 points), non-paroxysmal AF (9 points), diabetes mellitus (4 points), left atrial volume index (1 point per 10 ml/m2 rounded to the nearest integer), and the second (4.7 to < 7 ml/m2; 4 points) and third (≥ 7 ml/m2; 5 points) tertiles of the LAA volume index were independent risk factors LR. The above-mentioned risk factors were included in the integrated score model, and the C-index of the proposed score model was 0.715 (95 % confidence interval [CI] 0.679-0.752). LAA volume is an independent predictor of LR and the predictive model including LAA volume showed good discrimination power. These findings provide evidence for the inclusion of LAA volume in the risk stratification for AF recurrence in patients undergoing RFCA for AF.

A successfully treated case of primary purulent pericarditis complicated by cardiac tamponade and pneumopericardium.

Acute pericarditis is caused by various factors, but purulent pericarditis is rare. Primary purulent pericarditis in immunocompetent hosts is very rare in the modern antibiotics era. We report a successfully treated case of primary purulent pericarditis complicated with cardiac tamponade and pneumopericardium in an immunocompetent host. A 69-year-old female was referred from another hospital because of pleuritic chest pain with a large amount of pericardial effusion. She was diagnosed with acute pericarditis accompanied by cardiac tamponade. We performed emergency pericardiocentesis, with drainage of 360 ml of bloody pericardial fluid. The culture grew Streptococcus anginosus, confirming the diagnosis of acute purulent pericarditis. We performed pericardiostomy because cardiomegaly and pneumopericardium were aggravated after removal of the pericardial drainage catheter. The patient received antibiotics for a total of 23 days intravenously and was discharged with oral antibiotic therapy. Purulent pericarditis is one of the rare forms of pericarditis and is lifethreatening. A multimodality approach is required for proper diagnosis and treatment of this disease.

Non-genetic risk factors for atrial fibrillation are equally important in both young and old age: A nationwide population-based study.

AIMS: There are several non-genetic risk factors for new-onset atrial fibrillation, including age, sex, obesity, hypertension, diabetes, and alcohol consumption. However, whether these non-genetic risk factors have equal significance among different age groups is not known. We performed a nationwide population-based analysis to compare the clinical significance of non-genetic risk factors for new-onset atrial fibrillation in various age groups. METHODS AND RESULTS: A total of 9,797,409 people without a prior diagnosis of atrial fibrillation who underwent a national health check-up in 2009 were included. During 80,130,090 person-years of follow-up, a total of 196,136 people were diagnosed with new-onset atrial fibrillation. The impact of non-genetic risk factors on new-onset atrial fibrillation was examined in different age groups. Obesity, male sex, heavy alcohol consumption, smoking, hypertension, diabetes and chronic kidney disease were associated with an increased risk of new-onset atrial fibrillation. With minor variations, these risk factors were consistently associated with the risk of new-onset atrial fibrillation among various age groups. Using these risk factors, we created a scoring system to predict future risk of new-onset atrial fibrillation in different age groups. In receiver operating characteristic curve analysis, the predictive value of these risk factors ranged between 0.556 and 0.603, and no significant trends were observed. CONCLUSIONS: Non-genetic risk factors for new-onset atrial fibrillation may have a similar impact on different age groups. Except for sex, these non-genetic risk factors can be modifiable. Therefore, efforts to control non-genetic risk factors might have relevance for both the young and old.

Slit-based irrigation catheters can reduce procedure-related ischemic stroke in atrial fibrillation patients undergoing radiofrequency catheter ablation.

Open irrigation ablation catheters are now the standard in radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF). Among various irrigation catheters, laser-cut slit-based irrigation system (Cool Flex and FlexAbility) has a unique design to cool the catheter tip more efficiently. We aimed to assess the safety of slit-based irrigation catheters regarding prevention of procedure-related ischemic complication in AF patients undergoing RFCA. The analysis was performed with Korea University Medicine Anam Hospital RFCA registry. Procedure-related ischemic complication was defined as ischemic stroke or transient ischemic attack (TIA) occurring within 30 days after RFCA. Patients were divided into 3 groups: non-irrigation, hole-based irrigation, and slit-based irrigation catheter groups. A total of 3,120 AF patients underwent first RFCA. Non-irrigation, non-slit-based irrigation, and slit-based irrigation catheters were used in 290, 1,539, and 1,291 patients, respectively. As compared with non-irrigation and non-slit-based irrigation catheter groups, slit-based irrigation catheter group had significantly older age, higher prevalence of non-paroxysmal AF, large left atrial size, and decreased left atrial appendage flow velocity. The CHA2DS2-VASc score was not different among the 3 groups. Procedure-related ischemic complication occurred in 17 patients (0.54%) with 16 ischemic strokes and 1 TIA event: 5/290 (1.72%), 11/1,539 (0.71%), and 1/1,291 (0.08%) events in non-irrigation, non-slit-based irrigation, and slit-based irrigation catheter groups, respectively (p = 0.001). Slit-based irrigation catheter was superior in direct comparison with non-slit-based irrigation catheter (0.71% vs. 0.08%; p = 0.009). Slit-based irrigation catheters were highly effective in preventing procedure-related ischemic complications.

Impact of age on thromboembolic events in patients with non-valvular atrial fibrillation.

BACKGROUND: Age is a well-established risk factor for thromboembolic events in patients with atrial fibrillation (AF). However, the mechanism underlying the association between age and thromboembolic events in AF remains unknown. METHODS: The prognostic value of age as a risk factor for thromboembolic events was analyzed using data from the Korean National Health Insurance Service (NHIS). In a large-scale single-center registry, cardiac hemodynamic parameters were examined to elucidate the cause of increased risk of thromboembolic events in older patients. RESULTS: NHIS sample cohort data including 5896 patients with AF revealed that the risk of thromboembolic complication differed significantly according to age despite equal CHA2 DS2 -VASc score. In the registry of 2801 patients, age showed significant correlations with left atrium (LA) diameter, LA volume, E/e', pulmonary artery pressure, and LA appendage flow velocity. Older patients had a significantly higher prevalence of spontaneous echocontrast (odds ratio [OR] = 1.030; P < .001). Age (OR = 1.031; P < .001), E/e' (OR = 1.065; P = .004), and LA appendage flow velocity (OR = .988; P = .009) were significant predictors for thromboembolic events in multivariate analyses. In data from the NHIS, CHA2 DS2 -VASc score did not outperform age to predict thromboembolic events. CONCLUSIONS: Age is a significant risk factor for thromboembolic events in patients with AF, and old age is associated with adverse cardiac hemodynamics. This study suggests that older patients with AF are at high risk of thromboembolic events regardless of CHA2 DS2 -VASc score.

Effectiveness and Safety of Off-label Dosing of Non-vitamin K Antagonist Anticoagulant for Atrial Fibrillation in Asian Patients.

Non-vitamin K antagonist anticoagulants (NOACs) have been used to prevent thromboembolism in patients with atrial fibrillation (AF) and shown favorable clinical outcomes compared with warfarin. However, off-label use of NOACs is frequent in practice, and its clinical results are inconsistent. Furthermore, the quality of anticoagulation available with warfarin is often suboptimal and even inaccurate in real-world data. We have therefore compared the effectiveness and safety of off-label use of NOACs with those of warfarin whose anticoagulant intensity was accurately estimated. We retrospectively analyzed data from 2,659 and 3,733 AF patients at a tertiary referral center who were prescribed warfarin and NOACs, respectively, between 2013 and 2018. NOACs were used at off-label doses in 27% of the NOAC patients. After adjusting for significant covariates, underdosed NOAC (off-label use of the reduced dose) was associated with a 2.5-times increased risk of thromboembolism compared with warfarin, and overdosed NOAC (off-label use of the standard dose) showed no significant difference in either thromboembolism or major bleeding compared with warfarin. Well-controlled warfarin (TTR ≥ 60%) reduced both thromboembolism and bleeding events. In conclusion, the effectiveness of NOACs was decreased by off-label use of the reduced dose.

Different influence of cardiac hemodynamics on thromboembolic events in patients with paroxysmal and non-paroxysmal atrial fibrillation.

Blood stasis in left atrium (LA) or LA appendage (LAA) is thought to be the main cause of thrombus formation and systemic embolism in atrial fibrillation (AF) patients. Paroxysmal and non-paroxysmal AF differ significantly in various aspects. Impact of cardiac hemodynamics on systemic embolism might also differ between the 2 distinct AF entities. This study was performed to evaluate the influence of cardiac hemodynamics on systemic embolism in both paroxysmal and non-paroxysmal AF. Consecutive AF patients undergoing radiofrequency catheter ablation (RFCA) in Korea University Medical Center Anam Hospital between June 1998 and February 2018 were analyzed. Among 2,801 patients who underwent first-time RFCA, a total of 231 patients had either previous ischemic stroke, transient ischemic attack, or arterial embolism. In paroxysmal AF, LA diameter, LA volume (measured with magnetic resonance imaging), left ventricular (LV) ejection fraction, E/e', LAA flow velocity, and prevalence of spontaneous echocontrast (SEC) and dense SEC were significantly different between patients with and without thromboembolic events. However, only E/e' was different between patients with and without thromboembolic events in non-paroxysmal AF. The influence of LA diameter, LA volume, LV EF, LAA flow velocity, and dense SEC on thromboembolic events was significantly moderated by the type of AF. In conclusion, paroxysmal and non-paroxysmal AF might have a different mechanism responsible for thrombus formation and consequent embolic events. Relative contribution of hemodynamic parameters and other factors such as atrial myopathy to thromboembolic events in paroxysmal versus non-paroxysmal AF needs further evaluation.

Comparison of Renal Function Estimation Formulae for Dosing Direct Oral Anticoagulants in Patients with Atrial Fibrillation.

The Cockcroft-Gault (CG) formula is recommended to guide clinicians in the choice of the appropriate dosage for direct oral anticoagulants (DOACs). However, the performance of the CG formula varies depending on the patient's age, weight, and degree of renal function. We aimed to compare the validity of the CG formula with that of Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) and Modification of Diet in Renal Disease (MDRD) formulae for dosing DOACs. A total of 6268 consecutive patients on anticoagulants for atrial fibrillation (AF) were retrospectively investigated. Among underweight and elderly patients, the CG formula underestimated renal function compared with the non-CG formulae. However, the concordant rate of drug indications between the CG and the non-CG formulae was approximately 94%. On-label uses under the three formulae were associated with a lower risk of major bleeding (but not thromboembolism) compared to warfarin. Although we found differences in estimating renal function and the proportions of drug indications between the CG and non-CG formulae, the risks of thromboembolism and major bleeding were similar to those with warfarin regardless of which formula was used.

Clinical and Echocardiographic Risk Factors Predict Late Recurrence after Radiofrequency Catheter Ablation of Atrial Fibrillation.

The benefits of radiofrequency catheter ablation (RFCA) for patients with atrial fibrillation (AF) significantly decrease with late recurrence (LR). We aimed to develop a scoring system to identify patients at high and low risk for LR following RFCA, based on a comprehensive evaluation of multiple risk factors for AF recurrence, including echocardiographic parameters. We studied 2,352 patients with AF undergoing first-time RFCA in a single institution. The LR-free survival rate up to 5 years was measured using a Kaplan-Meier analysis. The influence of clinical and echocardiographic parameters on LR was calculated with a Cox-regression analysis. Duration of AF ≥4 years (hazard ratio [HR] = 1.75; p < 0.001), non-paroxysmal AF (HR = 3.18; p < 0.001), and diabetes (HR = 1.34; p = 0.015) were associated with increased risk of LR. Left atrial (LA) diameter ≥45 mm (HR = 2.42; p < 0.001), E/e' ≥ 10 (HR = 1.44; p < 0.001), dense SEC (HR = 3.30; p < 0.001), and decreased LA appendage flow velocity (≤40 cm/sec) (HR = 2.35; p < 0.001) were echocardiographic parameters associated with increased risk of LR following RFCA. The LR score based on the aforementioned risk factors could be used to predict LR (area under curve = 0.717) and to stratify the risk of LR (HR = 1.45 per 1 point increase in the score; p < 0.001). In conclusion, LR after RFCA is affected by multiple clinical and echocardiographic parameters. This study suggests that combining these multiple risk factors enables the identification of patients with AF at high or low risk for having arrhythmia recurrence.