Impact of ABO blood type on the risk of atrial fibrillation recurrence after catheter ablation.

Background: Blood types are classified based on the specific antigenic characteristics they possess. Despite documented associations between antigens and inflammation, a scarcity of data exists concerning the impact of antigens on atrial fibrillation (AF). Methods: OSHOH-rhythm study is a multi-center, prospective observational study of 601 patients who underwent catheter ablation for AF. We examined the correlation between blood type groups and both the incidence and recurrence of AF. Additionally, we analyzed the recurrence of AF across antigenic profiles. Results: The frequencies of individual blood types were 239 (39.8 %), 190 (31.6 %), 122 (20.3 %), and 50 (8.3 %) for A, O, B, and AB, respectively, aligning closely with the prevalent blood type distribution among the Japanese populace. During follow-up period (18.8 months, median), AF recurrence occurred in 96 patients (22.4 %) lacking the B antigen (A and O), and 26 patients (15.1 %) possessing B antigen (B and AB), respectively (Log-rank test: P = 0.034). A multivariate analysis demonstrated that blood types lacking the B antigen (hazard ratio [HR], 1.55; 95 % CI, 1.01 to 2.42; P = 0.037), hypertension (HR, 1.51; 95 % CI, 1.05 to 2.17; P = 0.026) and non-paroxysmal AF (HR, 1.70; 95 % CI, 1.17 to 2.47; P = 0.005) were independently associated with the recurrence of AF. Conclusions: This study elucidates that, despite the absence of direct correlation between blood types and the occurrence of AF, blood types devoid of the B antigen exhibit an enhanced predisposition to AF recurrence. Nonetheless, the intricate mechanism linking blood type to recurrence remains elusive, warranting further comprehensive foundational research on blood types.

Prolonged PR intervals are associated with epicardial adipose tissue and recurrence after catheter ablation in persistent atrial fibrillation.

Epicardial adipose tissue (EAT) has been reported to promote myocardial fibrosis and to affect intracardiac conduction. The PR interval reflects the conduction from the atria to the Purkinje fibers and may be associated with the EAT volume, especially in persistent atrial fibrillation (AF) patients. We aimed to investigate the relationship between the EAT and PR interval in patients with persistent AF. We enrolled 268 persistent AF patients who underwent catheter ablation (CA) and divided the patients into two groups: the normal PR interval group (PR interval less than 200 ms: Group N) and long PR interval group (PR interval 200 ms or more: Group L). We then analyzed the association between the total EAT volume around the heart and PR interval and calculated the ratio of the duration of the P wave (PWD) to the PR interval (PWD/PR interval). Moreover, we investigated whether a long PR interval was associated with the outcomes after ablation. The total EAT volume was significantly larger in Group L than Group N (Group N: 131.4 ± 51.8 ml vs. Group L: 151.3 ± 63.3 ml, p = 0.039). A positive correlation was also observed between the PWD/PR interval and EAT volume in Group L (r = 0.345, p = 0.039). A multivariate analysis also revealed that a long PR interval was independently associated with AF recurrence after CA (hazard ratio [HR] 2.071, p = 0.032). The total EAT volume was associated with a long PR interval, and a long PR interval was a significant risk factor for recurrence after ablation in persistent AF patients.

Devastating Worsening Renal Function Following the Initiation of Sacubitril/Valsartan: Falling Between Two Stools.

Previously prescribed antihypertensive agents were switched to the maximum dose of sacubitril/valsartan, without any upward titration, in two elderly hypertensive patients with chronic kidney disease who were hospitalized for treatment of congestive heart failure, in the hope of its decongestive, antihypertensive, and potential renoprotective actions. However, they quickly fell into oliguria and finally required hemodialysis. Sacubitril/valsartan should be initiated with careful attention in elderly patients with advanced renal dysfunction.

A Novel Hemostatic Belt Allowing Ambulation Soon After Atrial Fibrillation Ablation.

We aimed to develop a hemostatic device with physiological evidence that allows ambulation soon after atrial fibrillation (AF) ablation. We measured right femoral vein pressure in 57 participants to clarify why groin post-venipuncture rebleeding often occurs during the transition from supine to sitting under compression bandage application and found that it increased more than threefold when raising the upper body (8.6 ± 4.1 to 27.6 ± 6.9 mmHg; P < 0.001). Based on that data, we created a novel hemostatic belt. Its capability test including 25 participants demonstrated that the belt gave much higher compression pressures on the right groin while sitting than the compression bandage (59.5 ± 14.9 vs. 8.1 ± 4 mmHg; P < 0.001), achieving pressures above the maximum femoral vein pressure in 92% of participants. A randomized trial comparing the belt with compression bandage in 74 AF patients demonstrated that the belt reduced time to ambulation without any rebleeding (340 [92.5-360] vs. 360 [360-360] min; P < 0.001) and satisfied more patients. The novel hemostatic belt provided a much higher compression pressure on the right groin during the sitting position than the conventional compression bandage, achieving a pressure above the maximum femoral vein pressure in 92% of the participants.

Impact of Lipoprotein (a) on Long-Term Outcomes in Patients With Acute Myocardial Infarction.

BACKGROUND: Lipoprotein (a) (Lp(a)) is a complex circulating lipoprotein, and there is increasing evidence it is a risk factor for atherosclerotic cardiovascular disease (ASCVD). This study aimed to investigate the influence of Lp(a) serum levels on long-term outcomes after acute myocardial infarction (AMI).Methods and Results: Between January 2015 and January 2018, we enrolled 262 patients with AMI who underwent coronary angiography within 24 h of the onset of chest pain and had available Lp(a) data enabling subdivision into 2 groups: high Lp(a) (≥32 mg/dL: n=76) and low Lp(a) (<32 mg/dL: n=186). The primary endpoint was major adverse cardiac events (MACE), which was defined as a composite of cardiac death, nonfatal MI, and readmission for heart failure. Multivariate Cox regression analysis was performed to identify the predictors of MACE. The incidence of MACE was significantly higher in the high Lp(a) group than in the low Lp(a) group (32.8% vs. 19.6%, P=0.004). Multivariate analysis showed that Lp(a) ≥32 mg/dL was an independent predictor of MACE (hazard ratio 2.84, 95% confidence interval 1.25-6.60, P=0.013). CONCLUSIONS: High Lp(a) levels were associated with worse long-term outcomes after AMI, so Lp(a) may be useful for risk assessment.

Progression from paroxysmal to persistent atrial fibrillation in pacemaker patients with tachycardia-bradycardia syndrome: a multicenter study.

Progression from paroxysmal to persistent atrial fibrillation (AF) is occasionally encountered in patients with previous pacemaker implantation (PMI) for the treatment of tachycardia-bradycardia syndrome (TBS). We aimed to determine the rate of its incidence occurring within the early years after PMI and the predictors. We studied TBS patients who received PMI at 5 core cardiovascular centers. The end point was a conversion from paroxysmal to persistent AF. We extracted 342 TBS patients out of 2579 undergoing PMI. During 5 ± 3.1 years of follow-up, 114 (33.3%) reached the end point. The time to the end point was 2.9 ± 2.7 years. The event rates within a year and 3 years after the PMI were 8.8% and 19.6%, respectively. In the multivariate hazard analyses, hypertension (hazard ratio [HR] 3.2, P = 0.03) and congestive heart failure (HR 2.1, P = 0.04) were found to be independent predictors of the end point occurring within a year after the PMI. Congestive heart failure (HR 1.82, P = 0.04), left atrial diameter of ≥ 40 mm (HR 4.55, P < 0.001), and the use of antiarrhythmic agents (HR 0.58, P = 0.04) were independently associated with the 3-year end point. Prediction models including combinations of those 4 parameters for the 1- and 3-year incidence both exhibited a modest risk discrimination (both c-statistics 0.71). In conclusion, early progression from paroxysmal to persistent AF was less frequent than expected in the TBS patients with PMI. Factors related to atrial remodeling and no use of antiarrhythmic drugs may facilitate the progression.

Increased major bleeding incidence in atrial fibrillation patients with apixaban: a review of Japanese post-marketing surveillance studies of direct oral anticoagulants.

Large-scaled post-marketing surveillance studies (PMSSs) of 4 direct oral anticoagulants (DOACs) for stroke prevention in non-valvular atrial fibrillation (AF) were conducted since 2011 in Japan, and the results of the last one have recently been published. Each reported a more than acceptable ischemic stroke prevention. The major bleeding rates were also acceptably low and comparable to each other in the PMSSs of dabigatran (J-dabigatran), rivaroxaban (XAPASS), and edoxaban (ETNA-AF-Japan). However, the incidence in PMSS of apixaban (STANDARD) was more than double the others. This finding appeared to contradict the globally accepted theory that apixaban is less likely than other DOACs to cause bleeding events. Possible responsible mechanisms included (1) the age and kidney function, (2) concomitant antiplatelet therapy, (3) drug actions, (4) follow-up duration, and (5) dose reduction criteria. Similarities in the clinical background shared by the 4 different PMSSs' participants and knowledge from previous studies did not support a dominant contribution of any of those former 4 factors to the increased major bleeding incidence in STANDARD. A possibility of the 5th factor was then examined. An estimated calculation we created showed that apixaban's dose reduction criteria was strict enough to considerably reduce the opportunity for participants to take its reduced rather than standard dose. We then successfully simulated how the "strict" dose reduction criteria would have increased the bleeding event rates under DOAC therapy. The discussion in this review may therefore raise a question about the validity of the current dose reduction criteria of apixaban for Japanese AF patients.

Impact of SGLT2 inhibitors on old age patients with heart failure and chronic kidney disease.

BACKGROUND: The heart failure (HF) "pandemic" is an ongoing critical issue related to the aging population. Among the new heart failure medications, sodium-glucose cotransporter 2 inhibitors (SGLT2i) have been shown to provide clinical benefit in HF patients with chronic kidney disease (CKD). However, the efficacy and safety of SGLT2i in old age patients remains uncertain. METHODS: The OSHO-heart (Optimal Solution after Hospitalization in Onomichi for heart failure) is a prospective study of 213 patients aged ≥ 75 years-old hospitalized for acute decompensated HF with stage 3 to 4 CKD. The composite outcomes of HF rehospitalizations or cardiovascular death and the rate of decline in the estimated glomerular filtration rate (eGFR) were compared between the Loop (n = 76), tolvaptan (TLV) (n = 80) and SGLT2i (n = 57) groups, respectively. RESULTS: During follow-up (17.2 months, median), composite of HF rehospitalization or cardiovascular death events occurred in 30 (39.5%) in Loop, 19 (23.8%) in TLV and 8 (14%) in SGLT2i groups, respectively (Log-rank: P = 0.015). A multivariate analysis demonstrated that the continuation of SGLT2i (hazard ratio, 0.41; 95% CI, 0.19 to 0.78; P = 0.022) and an EF < 30% (hazard ratio, 2.19; 95% CI, 1.22 to 3.92; P = 0.009) were independently associated with the composite outcome. The rate of decline in the eGFR was significantly less in TLV and SGLT2i groups than Loop group (-1.64 vs. -1.28 vs. -5.41 ml/min/1.73 m2 per year, P = 0.007, respectively). CONCLUSIONS: SGLT2i therapy might reduce the combined risk of HF hospitalizations or cardiac death and preserve a worsening renal function in old age patients with HF and CKD.

Peripheral arterial tone during active standing.

Active standing test is clinically used to detect inadequate sympathetic nervous system response to the orthostasis. Peripheral arterial tone (PAT) is a recently developed technology whereby sympathetic activity can be measured through monitoring the digit arterial pulsatile volume. We aimed to determine the response of PAT to the orthostasis. The PAT and short-time frequency domain heart rate variability (HRV) were simultaneously measured during a 5.5-min active standing test in volunteers. The endpoints were changes in the PAT and ratio of low frequency to high frequency (LH/HF) before and after the postural changes: sitting→standing→sitting again. The blood pressure (BP) was constant throughout the test while the heart rate increased during standing in 54 participants. The natural logarithm of the mean LF/HF increased in the standing position (sitting, standing, and sitting again, mean±standard deviation, 1.3±1.04, 1.73±1.15, and 1.51±0.94; p=0.006), and the natural logarithm of its peak value was the highest also while standing (2.58±1.19, 3.08±1.2, and 2.85±1.05; p=0.007). The mean PAT (487.5±277.7, 314.5±180.4, and 458.1±244.3; p <0.001) and its nadir value (341.8±204.8, 189.4±119.2, and 264.3±157.6; p <0.001) declined during standing, and reascended after sitting again. The percent change before and after the standing in mean PAT was not correlated with that of the mean LF/HF. In conclusion, the PAT changed independently of and inversely with the LF/HF during the orthostatic test while the BP remained constant, possibly reflecting peripheral vasocontraction needed for the BP homeostasis.

Does atrial fibrillation ablation worsen preexisting anemia? Another anemia paradox in DOAC era.

BACKGROUND: There is a concern about worsening anemia after atrial fibrillation (AF) ablation in anemic patients. We aimed to clarify whether or not patients with anemia who are on an oral anticoagulant therapy are more likely to lose blood after AF ablation. METHODS: We studied AF patients in 3 cardiovascular centers who skipped a single dose of a direct oral anticoagulant prior to the ablation, and compared the drop in the hemoglobin level 24 hours after the procedure and bleeding complications between the patients with and without preexisting anemia. RESULTS: We identified 183 (15.7%) patients with anemia at baseline out of 1163 patients. The reduction in the hemoglobin level (-0.39±0.71 vs. -0.93±0.9 g/dL; p<0.001) was smaller in the anemic than non-anemic patients. A fall in the hemoglobin level of ≥2 g/dL, which is a guideline-defined significant hemoglobin drop, was less common in anemic patients (1.6% vs. 11.3%; p<0.001). A female gender [odds ratio (OR) 1.62, confidence interval (CI) 1.07-2.45; p=0.02], persistent or long-standing persistent versus paroxysmal AF (OR 1.67, CI 1.13-2.49; p=0.01), ORBIT score ≥3 (OR 3.5, CI 1.34-8.94; p=0.01), and preexisting anemia (OR 0.02, CI 0.004-0.14; p<0.001) were independently associated with the fall in the hemoglobin level of ≥2 g/dL. No difference was noted in the rate of major bleeding complications (1.6% vs. 1.2%; p=0.72). CONCLUSIONS: Paradoxically, patients with preexisting anemia may be less likely to lose blood following AF ablation.

Intra-procedural anticoagulation and post-procedural hemoglobin fall in atrial fibrillation ablation with minimally interrupted direct oral anticoagulants: comparisons across 4 drugs.

PURPOSE: Thromboembolic or hemorrhagic complications related to atrial fibrillation (AF) ablation are rare, and thus, it is difficult to compare their frequency across different direct oral anticoagulants (DOACs). We aimed to compare the intra-ablation blood coagulability and post-procedural hemoglobin fall as alternatives to those complications across 4 DOACs. METHODS: We enrolled AF patients younger than 65 years old in 3 cardiovascular centers who skipped a single dose of apixaban, dabigatran, edoxaban, and rivaroxaban, prior to the ablation. Endpoints included the activated clotting time (ACT), heparin requirement during the ablation, and drop in the hemoglobin level 24 h after the procedure. RESULTS: The time-course curves of the ACT differed significantly across the patients with apixaban (N = 113), dabigatran (N = 130), edoxaban (N = 144), and rivaroxaban (N = 81), with its highest level in the dabigatran group (P < 0.001). The average ACT was greater in the dabigatran group than in the other groups (312.3 ± 34, 334.4 ± 44, 308.1 ± 41, and 305.8 ± 34.7 s; P < 0.001). A significant difference was noted in total heparin requirement across the patient groups (3990.2 ± 1167.9, 3890.4 ± 955.3, 4423.8 ± 1051.6, and 3972 ± 978.7 U/m2/h; P < 0.001), with its greatest amount in the edoxaban group. The reduction in the hemoglobin level was similar (- 0.93 ± 0.92, - 0.88 ± 0.79, - 0.89 ± 0.97, - 0.95 ± 1.23 g/dL; P = 0.94). No inter-group difference was noted in the rate of major or minor bleedings (0.9%, 2.3%, 1.4%, and 3.7%; P = 0.51), and no thromboembolic events were encountered. CONCLUSION: A difference in DOACs may have an impact on intra-ablation anticoagulation; however, it may not be on the procedural blood loss in the setting of a single skip.

Remaining activity of temporary interrupted direct oral anticoagulants and its impact on intra-ablation heparinization in patients with atrial fibrillation: Comparisons across four drugs and two dose regimens.

BACKGROUND: Atrial fibrillation (AF) ablation with minimally interrupted direct oral anticoagulants (DOACs) may raise a concern about their remaining activity. We tested the residual activity of four different DOACs and its impact on intraprocedural heparinization in patients undergoing AF ablation. METHODS: We measured the anti-factor Χa activity for rivaroxaban, apixaban, and edoxaban, and serum DOAC concentration for rivaroxaban, apixaban, and dabigatran, 24 hours after the last intake in patients undergoing AF ablation treated with standard or reduced doses of DOACs. The heparin requirement during the procedure was also measured. RESULTS: We enrolled 34 patients with rivaroxaban, 35 with apixaban, 32 with edoxaban, and 31 with dabigatran, and among them, 30 were treated with reduced doses. The anti-factor Χa activity was the highest in the apixaban group among the patients with standard doses. The DOAC concentration was paradoxically lower in patients with standard doses than in those with reduced doses among the patients with rivaroxaban (34.3 ± 19.8 vs 56.6 ± 7.7 ng/mL; P = .01) and dabigatran (12.6 ± 10.6 vs 23.4 ± 14.7 ng/mL; P = .03). The total heparin requirement per body surface area had significant correlations with the anti-factor Χa activity (r = -.36) and DOAC concentration (r = -.32). Two different multiple linear regression models (adjusted R2 = 0.56 and 0.6, respectively) revealed that the anti-factor Χa activity (ß = -.28; P = .002) and DOAC concentration (ß = -.38; P < .001) were independent determinants of the total heparin requirement. CONCLUSIONS: Factors determining residual DOAC activity may include its type and dose regimen, and it may influence the heparin requirement during AF ablation.

Prognostic significance of oscillatory ventilation at rest in patients with advanced heart failure undergoing cardiopulmonary exercise testing.

BACKGROUND: Among heart failure patients diagnosed as having exertional oscillatory ventilation (OV), some present with OV at rest that persists during exercise, and others develop OV only after the onset of exercise during cardiopulmonary exercise (CPX) testing. We tested whether or not there was any difference in the prognostic significance between the two abnormal breathing patterns. METHODS: Patients with New York Heart Association class III-heart failure were categorized into the following 3 groups according to their ventilation pattern during the CPX: patients with an OV pattern at rest that persisted for ≥60% of the exercise test at an amplitude of ≥15% of the average resting value (group 1), patients with the same abnormal ventilatory pattern as group 1 that was observed only during exercise (group 2), and patients without any OV (group 3). The patients were followed-up for at least 2 years to assess the composite outcome of cardiac death or hospitalization for worsening heart failure. RESULTS: The occurrence of the composite outcome differed significantly across the groups with its highest occurrence in group 1 (21/29 [72.4%], 15/38 [39.5%] and 48/167 [28.7%]; log-rank P < 0.001). In multivariate hazard analyses, an N-terminal pro-brain natriuretic peptide of >900 pg/mL (hazard ratio [HR] = 1.72, P = 0.04), and group 1 (HR 2.03, P = 0.02) were independently associated with the composite outcome. CONCLUSIONS: Checking for the resting OV prior to incremental exercise during CPX testing may be helpful in risk-stratification among subjects with advanced heart failure.

Residual anticoagulation activity in atrial fibrillation patients with temporary interrupted direct oral anticoagulants: Comparisons across 4 drugs.

BACKGROUND: Atrial fibrillation (AF) ablation with minimally interrupted direct oral anticoagulants (DOACs) predominates, possibly raising concern about their remaining activity during the procedure. We aimed to examine residual activities of 4 different DOACs. METHODS: The serum DOAC concentration and anti-factor Χa activity were measured 3 and 24 h after the last intake in patients undergoing AF ablation who were treated with rivaroxaban, apixaban, edoxaban, or dabigatran. RESULTS: The reduction in the apixaban concentration between the 2 blood sampling time points (N = 32, mean ±â€¯SD, -67.7 ±â€¯14.8% [231.6 ±â€¯93.1 to 71.9 ±â€¯31.8 ng/mL]) was smaller than that for rivaroxaban (N = 28, -83.6 ±â€¯10.9% [234.2 ±â€¯96.6 to 34.3 ±â€¯19.8 ng/mL]; P < 0.001) and dabigatran (N = 20, -90.7 ±â€¯7.3% [135.3 ±â€¯68.3 to 12.6 ±â€¯10.6 ng/mL]; P < 0.001), with its greatest value measured 24 h after the last intake in the apixaban group. The decrease in the anti-factor Χa activity was also smaller in the patients with apixaban (-73.8 ±â€¯12.7%) than with rivaroxaban (-87.9 ±â€¯7.9%; P < 0.001) and edoxaban (N = 22, -81.9 ±â€¯15.2%; P = 0.049), and its remaining activity 24 h after the last dose was the highest in the apixaban group. A serum DOAC concentration measured 24 h after the last dose of >30 ng/mL was seen in 41 (51.3%) patients with rivaroxaban, apixaban, or dabigatran, and it was independently associated with apixaban versus rivaroxaban (odds ratio 5.0; P = 0.01) and apixaban versus dabigatran (odds ratio 74.0; P < 0.001). CONCLUSION: The pattern of drug elimination from blood may vary depending on DOACs, and their residual activity may not be negligible even 24 h after the last intake.

Cardiac electrophysiological characteristics of silent paroxysmal atrial fibrillation: What causes asymptomaticity?

BACKGROUND: A diagnosis of silent paroxysmal atrial fibrillation (AF) is highly challenging due to its asymptomatic and intermittent nature. The goal of the present study was to clarify its asymptomaticity with the use of a comprehensive electrophysiological approach. METHODS: We prospectively compared (a) 24-hour Holter monitoring data, (b) invasive cardiac electrophysiological properties, (c) AF inducibility, and (d) outcome of radiofrequency catheter ablation between patients with symptomatic paroxysmal AF and those with silent paroxysmal AF, defined as transient asymptomatic AF detected by chance. RESULTS: Patients with silent paroxysmal AF (N = 57) were more likely than patients with symptomatic paroxysmal AF (N = 282) to be male (75.4% vs 56.7%; P = .009), and to have a previous stroke (17.5% vs 6.7%; P = .008), more prolonged atrio-His interval (114.9 ± 29.1 vs 105.5 ± 24.1 ms; P = .01), longer atrioventricular nodal effective refractory period (352.3 ± 103 vs 318.2 ± 77.2 ms; P = .007), slower Wenckebach cycle length (488.5 ± 83.9 vs 443.3 ± 74.9 ms; P < .001), and lower maximum heart rate during AF (128.7 ± 31.9 vs 143.9 ± 29.6 beats/min; P = .02). Atrial ectopy (median [interquartile range], 385 [88, 2430] vs 207 [73.8, 870.8] beats/24 h; P = .02) and pharmacological AF induction (66.7% vs 43.2%; P = .02) were more common in silent paroxysmal AF patients. There was no difference in the 1-year freedom from AF following the ablation between the two patient groups. CONCLUSIONS: The more attenuated atrioventricular conduction properties in silent paroxysmal AF patients may explain their asymptomatic nature, and their higher likelihood of atrial arrhythmias may increase the chance to detect AF episodes. Whether or not they benefit from catheter ablation is uncertain.

Correction to: Differences in prothrombotic response between the uninterrupted and interrupted apixaban therapies in patients undergoing cryoballoon ablation for paroxysmal atrial fibrillation: a randomized controlled study.

In the original publication of the article, the table 2 was published incorrectly.

A mimic of tachycardia-bradycardia syndrome in a patient with long-standing persistent atrial fibrillation.

Pause following incessant tachycardia is often encountered in clinical practice. We encountered a rare arrhythmic condition mimicking tachycardia-bradycardia syndrome. We hereby describe the step-by-step diagnostic process.

Differences in prothrombotic response between the uninterrupted and interrupted apixaban therapies in patients undergoing cryoballoon ablation for paroxysmal atrial fibrillation: a randomized controlled study.

Periprocedural bleeding and thromboembolic events are worrisome complications of catheter ablation for atrial fibrillation (AF). Periprocedural anticoagulation management could decrease the risk of these complications. However, evaluation of the complications from pulmonary vein isolation using cryoballoon related to different anticoagulation strategies is limited. Therefore, we aimed to compare prothrombotic responses as assessed on the basis of D-dimer levels between the uninterrupted and interrupted apixaban therapies during cryoballoon ablation. Ninety-seven consecutive patients with paroxysmal AF scheduled to undergo cryoballoon ablation were randomly assigned in a 1:2 ratio to uninterrupted apixaban therapy (Group 1, n = 32) or interrupted apixaban therapy (Group 2, n = 65). D-Dimer levels were measured immediately before the ablation, at the end of the ablation, and 24 and 48 h after the procedure. No statistical difference was observed in the baseline characteristics between the two groups. The rates of hemorrhagic complications were similar in both groups (major bleeding: 3.1 vs. 1.5%; p = 0.61, and minor bleeding: 3.1 vs. 4.6%; p = 0.73, respectively). No thromboembolic events occurred in either group. However, D-dimer levels 48 h after the ablation increased more markedly following the procedure in Group 2 than in Group 1 (from 0.58 ± 0.16 to 1.01 ± 0.42 µg/mL vs. 0.58 ± 0.20 to 0.82 ± 0.25 µg/mL; p = 0.01). In conclusion, uninterrupted apixaban therapy during the periprocedural period of cryoballoon ablation for AF did not increase the risk of bleeding in this study and might reduce the periprocedural risk of subclinical hypercoagulable state.

Ser96Ala genetic variant of the human histidine-rich calcium-binding protein is a genetic predictor of recurrence after catheter ablation in patients with paroxysmal atrial fibrillation.

BACKGROUND: Atrial fibrillation (AF) recurrence after radiofrequency catheter ablation (RFCA) still remains a serious issue. Ca2+ handling has a considerable effect on AF recurrence. The histidine-rich calcium-binding protein (HRC) genetic single nucleotide polymorphism (SNP), rs3745297 (T>G, Ser96Ala), is known to cause a sarcoplasmic reticulum Ca2+ leak. We investigated the association between HRC Ser96Ala and AF recurrence after RFCA in paroxysmal AF (PAF) patients. METHODS AND RESULTS: We enrolled PAF patients who underwent RFCA (N = 334 for screening and N = 245 for replication) and were genotyped for HRC SNP (rs3745297). The patient age was younger and rate of diabetes and hypertension lower in the PAF patients with Ser96Ala than in those without (TT/TG/GG, 179/120/35; 64±10/60±12/59±13 y, P = 0.001; 18.5/ 9.2/8.6%, P = 0.04 and 66.1/50.0/37.1%, P = 0.001, respectively). During a mean 19 month follow-up, 57 (17.1%) patients suffered from AF recurrences. The rate of an Ser96Ala was significantly higher in patients with AF recurrence than in those without in the screening set (allele frequency model: odds ratio [OR], 1.80; P = 0.006). We also confirmed this significant association in the replication set (OR 1.74; P = 0.03) and combination (P = 0.0008). A multivariate analysis revealed that the AF duration, sinus node dysfunction, and HRC Ser96Ala were independent predictors of an AF recurrence (hazard ratio [HR], 1.04, P = 0.037; HR 2.42, P = 0.018; and HR 2.66, P = 0.007, respectively). CONCLUSION: HRC SNP Ser96Ala is important as a new genetic marker of AF recurrence after RFCA.