Electrophysiological evidence of right atrial epicardial connections in a case with recurrent common atrial flutter.

The majority of the cavotricuspid isthmus (CTI) region consists of discretely arranged muscle bundles separated by connective tissue. Heterogeneity in the anatomic arrangement of the muscle bundles results in differences in the endocardial and epicardial activation patterns. We present a case of recurrent atrial flutter (AFL) despite the presence of a complete endocardial CTI block. We found epicardial-endocardial breakthrough (EEB) sites on the right atrial high septum. In addition, the epicardial excitation confirmed by endocardial activation mapping was detected as far-field potentials. Radiofrequency ablation was performed at the EEB site. No AFL has recurred for 12 months after the present procedure.

Significance of mitral L-waves in predicting late recurrences of atrial fibrillation after radiofrequency catheter ablation.

BACKGROUND: The mitral L-wave, a prominent mid-diastolic filling wave in echocardiographic examinations, is associated with severe left ventricular diastolic dysfunction. The relationship between the mitral L-wave and outcome of catheter ablation (CA) in patients with atrial fibrillation (AF) has not been established. This study aimed to evaluate the predictive value of mitral L-waves on AF recurrence after CA. METHODS: This was a retrospective and observational study in a single center. One hundred forty-six patients (mean age; 63.9 [56.0-72.0] years, 71.9% male) including 66 non-paroxysmal AF patients (45.2%) who received a first CA were enrolled. The mitral L-waves were defined as a distinct mid-diastolic flow velocity with a peak velocity ≥20 cm/s following the E wave in the echocardiographic examinations before CA. The patients enrolled were divided into groups with (n = 31, 21.2%) and without (n = 115, 78.8%) mitral L-waves. Univariate and multivariate analyses were carried out to determine the predictive factors of late recurrences of AF (LRAFs), which meant AF recurrence later than 3 months after the CA. RESULTS: During a follow-up of 28.8 (15.0-35.8) months, the ratio of LRAFs in patients with mitral L-waves was significantly higher than that in those without mitral L-waves (15 [46.9%] vs. 16 [14.0%], p < .001). A multivariate analysis using a Cox proportional hazard model revealed that the mitral L-waves were a significant predictive factor of LRAFs (hazard ratio: 3.09, 95% confidence interval: 1.53-6.24, p = .002). CONCLUSION: The appearance of mitral L-waves could predict LRAFs after CA.

The inducibility and focus of atrial fibrillation after ablation in patients with tachycardia-induced heart failure.

BACKGROUND: The inducibility of atrial fibrillation (AF) and incidence of nonpulmonary vein (nonPV) triggers in patients with heart failure (HF) have not been elucidated. Furthermore, the relationship between AF triggers and the change in the left ventricular (LV) function after catheter ablation (CA) remains unclear. METHODS: A total of 101 consecutive patients with a history of HF due to tachycardia who underwent CA of AF were prospectively enrolled (64.8 ± 10.7 years, male 72.3%, and paroxysmal AF 15.8%). According to the AF inducibility by isoproterenol (ISP), the patients were divided into two groups: inducible AF (66.3%) and noninducible AF (33.7%). Furthermore, inducible AF was categorized into a PV type (61.2%) and nonPV type (38.8%). This study investigated the AF recurrence and change in the LV ejection fraction (LVEF) after CA. RESULTS: AF recurred in 35 patients (34.7%) during the follow-up period (41.6 ± 26.8 months). Kaplan-Meier curves showed that patients with noninducible AF had just as bad an AF recurrence rate as those with the nonPV type. Cox proportional hazards models also revealed that noninducible AF (Hazard-ratio, 5.74; 95% CI, 1.81-18.13) was associated with a higher risk of recurrence. The LVEF significantly improved after the CA (from 49.1 ± 16.3% to 67.0 ± 7.9%). However, the nonPV type was associated with a lower improvement in the LVEF (Odds-ratio, 0.18; 95% CI, 0.05-0.70). CONCLUSION: The AF inducibility was associated with AF recurrence. Furthermore, the nonPV triggers were associated with a lesser improvement in the LVEF. Confirming the AF inducibility and triggers was important to predict the outcome after CA.

Predictive value of the cardio-ankle vascular index for recurrence of atrial fibrillation after catheter ablation.

BACKGROUND: The predictive value of the cardio-ankle vascular index (CAVI) for estimating the efficacy outcome of catheter ablation (CA) in atrial fibrillation (AF) patients is unclear. We aimed to examine the predictive performance of the CAVI for recurrences of atrial arrhythmias after CA. METHODS: We enrolled a total of 193 patients with AF (paroxysmal 126 and non-paroxysmal 67) who underwent initial CA procedures at our institute, and CAVI measurements were conducted between January 2016 and March 2017. We evaluated recurrences of atrial arrhythmias after the first CA procedure as a clinical outcome. The CAVI value was assessed and the enrolled patients were divided according to the optimal CAVI value cut-off point (9.5) in the atrial arrhythmia recurrence group. RESULTS: During a mean follow-up of 31.3 (17.5-43.0) months, 74 (32.5%; PaAF 41 and 49.3%; non-PaAF 33) patients had recurrences of atrial arrhythmias. The recurrence ratio of atrial arrhythmias was significantly higher in patients with a high CAVI (≥9.5) than those with a low CAVI (<9.5) (log rank test; p = 0.018). A univariate analysis showed the association between higher CAVI values and recurrences of atrial arrhythmias (p = 0.072). Multivariate analyses using a Cox proportional hazard model after adjusting for other clinical factors revealed that the CAVI value was determined to be a significant predictive factor of a recurrence of atrial arrhythmias after CA (Hazard ratio: 1.44, 95% confidence interval: 1.17-1.78, p < 0.01). CONCLUSIONS: The CAVI was significantly associated with a recurrence of atrial arrhythmias after CA in AF patients.

Role of Intracardiac Defibrillation During the Ablation Procedure as a Predictor of Atrial Fibrillation Recurrence After Catheter Ablation.

Intracardiac defibrillation (IDF) is performed to restore sinus rhythm (SR) during radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF). This study aimed to investigate the change in the IDF threshold before and after RFCA during the ablation procedure and determine whether the IDF threshold after RFCA was associated with the AF substrate and AF recurrence. A total of 141 consecutive patients with drug-refractory persistent AF (age 62.5 ± 10.3 years, 84.4% male) were enrolled in this study. Before RFCA, we initially performed IDF with an output of 1 J. When IDF failed to restore SR, the output was gradually increased to 30 J. After RFCA, we attempted pacing-induced AF to provoke other focuses of AF. When AF was induced, we performed IDF again to terminate AF with outputs of 1 to 30 J. The change in the IDF threshold to restore SR before and after RFCA was evaluated. After RFCA, the IDF threshold for restoring SR significantly decreased (from 11.5 ± 8.6 J to 4.0 ± 3.8 J, P < 0.001). During the follow-up (24.3 ± 12.2 months), SR was maintained in 107 patients (75.9%). The multivariate analysis using a Cox proportional-hazards model revealed that an IDF threshold of > 5 J after RFCA was significantly associated with the AF recurrence (HR, 3.99; 95% confidence interval 1.93-8.22; P = 0.0001). RFCA decreased the IDF threshold for restoring SR in patients with persistent AF. The IDF output of > 5 J after RFCA could be a predictor of AF recurrence independent of the AF substrate.

Comparison of Landiolol and Digoxin as an Intravenous Drug for Controlling the Heart Rate in Patients with Atrial Fibrillation and Severely Depressed Left Ventricular Function.

Clinical experience with landiolol use in patients with atrial fibrillation (AF) and a severely depressed left ventricular (LV) function is limited. We compared the efficacy and safety of landiolol with that of digoxin as an intravenous drug in controlling the heart rate (HR) during AF associated with a very low LV ejection fraction (LVEF).We retrospectively analyzed 53 patients treated with landiolol (n = 34) or digoxin (n = 19) for AF tachycardias with an LVEF ≤ 25. The landiolol dose was adjusted between 0.5 and 10 µg/kg/minute according to the patient's condition. The response to treatment was defined as a decrease in the HR of ≤ 110/minute, and that decreased by ≥ 20% from baseline.There were no significant differences between the two groups regarding the clinical characteristics. The responder rate to landiolol at 24 hours was significantly higher than that to digoxin (71.0% versus 41.2%; odds ratio: 4.65, 95% confidence interval: 1.47-31.0, P = 0.048). The percent decrease in the HR from baseline at 1, 2, 12, and 24 hours was greater in the landiolol group than in the digoxin group (P < 0.01, P = 0.071, P = 0.036, and P = 0.016, respectively). The systolic blood pressure (SBP) from baseline within 24 hours after administering landiolol was significantly reduced, whereas digoxin did not decrease the SBP over time. Hypotension (< 80 mmHg) occurred in two patients in the landiolol group and 0 in the digoxin group (P = 0.53).Landiolol could be more effective in controlling the AF HR than digoxin even in patients with severely depressed LV function. However, careful hemodynamic monitoring is necessary when administering landiolol.

Comparison of the Transdermal Bisoprolol Patch with Oral Bisoprolol Fumarate Administration as a Therapeutic Agent for Idiopathic Frequent Premature Ventricular Contractions.

The transdermal bisoprolol patch (TB) was designed to maintain a sustained concentration of bisoprolol in plasma by a higher trough concentration than oral bisoporolol (OB). We compared the efficacy between TB and OB in patients with idiopathic premature ventricular contractions (PVCs) while considering their duration of action.A total of 78 patients with a PVC count of ≥ 3,000 beats/24 hours were divided into groups treated with TB 4 mg (n = 43) or OB 2.5 mg (n = 35). PVCs were divided into positive heart rate (HR) -dependent PVCs (P-PVCs) and non-positive HR-dependent PVCs (NP-PVCs) based on the relationship between the hourly PVC density and hourly mean HR. Twenty-four-hour Holter electrocardiograms were performed before and 1 to 3 months after the initiation of therapy.There were no significant between-group differences in the baseline characteristics. Both the TB (from 14.6 [9.9-19.2] to 7.6 [1.7-15.8]%, P < 0.001) and OB (from 13.2 [7.6-21.9] to 4.6 [0.5-17.0]%, P = 0.0041) significantly decreased the PVC density, and there was no significant difference between the two groups (P = 0.73). Compared to OB, the TB had similar effects in reducing the PVC density for P-PVCs (P = 0.96), and NP-PVCs (P = 0.71). The TB significantly decreased the P-PVC density from baseline not only during day-time (P < 0.001) but also night-time (P = 0.0017), while the OB did not significantly decrease the P-PVC density from baseline during night-time (P = 0.17).Compared to OB, the TB could be used with the same efficacy of reducing idiopathic PVCs. The TB may be a more useful therapeutic agent than OB for P-PVCs during a 24-hour period.

Clinical Factors Associated with a Successful Catheter Ablation Outcome in Elderly Patients with Atrial Fibrillation.

Catheter ablation is currently an established treatment for symptomatic paroxysmal atrial fibrillation (AF). We focused on elderly patients with a high prevalence of AF and attempted to identify the clinical factors associated with unsuccessful ablation outcomes.Among 735 consecutive patients who underwent AF ablation procedures, 108 (14.7%, 66 men) aged ≥ 75 years were included. Of them, 80 had paroxysmal AF, and the remaining 28 non-paroxysmal AF. All patients underwent pulmonary vein (PV) isolation and occasionally additional ablation. When AF recurred, redo ablation procedures were performed if the patient so desired.The mean number of ablation procedures was 1.1 ± 0.4 times per patient. During a mean follow-up of 38.7 ± 21.7 months, sinus rhythm was maintained in 100 patients (92.6%) without any antiarrhythmic drugs, but not in the remaining 8 (7.4%). Left atrial diameter (LAD, P < 0.001), left ventricular (LV) systolic diameter (P < 0.001), LV diastolic diameter (P = 0.001), non-PV AF foci (P = 0.036), and diabetes (P = 0.045) were associated with unsuccessful ablation procedures. Multivariate logistic regression analysis revealed a large LAD and non-PV AF foci were significant independent predictors of AF recurrences, with odds ratios of 0.76 (P = 0.019) and 0.04 (P = 0.023), respectively. In a total of 124 procedures, one major (0.8%) and 11 minor (8.9%) complications occurred.In elderly AF patients, catheter ablation of AF is effective and safe. Non-PV AF foci and a large LAD were independent clinical predictors of unsuccessful AF ablation outcomes.

Impact of Atrial Fibrillation Triggers on Long-Term Outcomes of a Second Catheter Ablation of Nonparoxysmal Atrial Fibrillation.

Background: Catheter ablation (CA) of atrial fibrillation (AF) triggers, including non-pulmonary vein (PV) foci, contributes to improved procedural outcomes. However, the clinical significance of an AF trigger ablation during second CA procedures for nonparoxysmal AF is unknown. Methods and Results: We enrolled 94 patients with nonparoxysmal AF undergoing a second CA. Intracardiac cardioversion during AF using high-dose isoproterenol was performed to determine the presence or absence of AF triggers. PV re-isolations were performed if PV potentials recurred, and if AF triggers appeared from any non-PV sites, additional ablation was added to those sites. We investigated the incidence of atrial arrhythmia recurrence (AAR) >3 months post-CA. Of the 94 enrolled patients, AF triggers were identified in 65 (69.1%), and of those with AF triggers, successful elimination of the triggers was achieved in 47 patients (72.3%). Multivariate analysis revealed that no observed AF triggers were a significant predictor of AAR (hazard ratio [HR] 1.97, 95% confidence interval [CI] 1.21-3.46, P=0.019). In a subanalysis of the patients with AF triggers, multivariate analysis showed that unsuccessful trigger ablation was significantly associated with AAR (HR 5.84, 95% CI 2.79-12.22, P<0.01). Conclusions: Having no observed AF triggers during a second CA session significantly increased the risk of AAR, as did unsuccessful CA of AF triggers.

Relationship between the nutritional status and safety and efficacy outcomes in atrial fibrillation patients aged 80 years and over receiving oral anticoagulants.

BACKGROUND: Malnutrition has been reported to be associated with worse clinical outcomes in various cardiovascular diseases. We aimed to investigate the clinical significance of the nutritional status in atrial fibrillation (AF) patients aged 80 years and over receiving oral anticoagulants (OACs), focusing on the difference between direct OACs (DOACs) and warfarin treatment. METHODS: This was a retrospective and observational study. We enrolled 332 consecutive AF patients aged 80 years and over who were treated with OACs: DOACs (n = 256) and warfarin (n = 76). A controlling nutritional status (CONUT) score was used to evaluate the nutritional status. The enrolled patients were divided into two groups based on the CONUT score: CONUT score <5 (n = 239) and CONUT score ≥5 (n = 93) groups. We investigated the relationship between the nutritional status and clinical outcomes. RESULTS: The CONUT score ≥5 group had significantly higher incidence of major bleeding (MB) compared to the CONUT score <5 group (4.6/100 person-years vs. 0.7/100 person-years, p < 0.01). On Cox hazard analysis, CONUT score ≥5 group was significantly associated with increased MB compared with the CONUT score <5 group (hazard ratio: 5.80, 95% confidence interval: 1.44-23.33, p = 0.013). In the DOAC group, the incidence of MB did not differ between the CONUT score ≥5 and CONUT score <5 groups (p = 0.54). In the warfarin group, MB occurred more frequently in the CONUT score ≥5 group than CONUT score <5 group (p < 0.01). There was no significant difference in the incidence of thromboembolic events between the CONUT score ≥5 and CONUT score <5 groups in both the DOAC and warfarin groups. CONCLUSIONS: The prognostic values of the nutritional status based on the CONUT score for MB differed between AF patients aged 80 years and over receiving DOACs and those receiving warfarin. It may be favorable to use DOACs to avoid bleeding events in those with malnutrition.

Early electrocardiographic indices for predicting chronic doxorubicin-induced cardiotoxicity.

BACKGROUND: Dealing with chemotherapy-related cardiac dysfunction (CTRCD) remains a significant problem complicated by the difficulty in early detection of cardiotoxicity. Electrocardiogram (ECG) is expected to be the most realistic methodology due to lower cost-performance and non-invasiveness. We investigated the long-term visual fluctuations in the ECG waveforms in patients with chronic doxorubicin (DOX)-induced cardiotoxicity to identify ECG indices for the early detection of cardiotoxicity. METHODS: We conducted a retrospective case series study by reviewing the medical records of 470 consecutive patients with malignant lymphoma who were treated with DOX at our institute between January 2010 and December 2017. Of them, 23 (4.9%) patients developed left ventricular dysfunction and were diagnosed with CTRCD using echocardiography. We assessed the ECG indices on 12-lead ECG recordings before and after treatment in 15 patients; eight patients were excluded due to conduction disturbances or atrial fibrillation. RESULTS: CTRCD was detected at a median of 475 (interquartile range, IQR: 341-1333) days after initiating chemotherapy. The evaluation of ECG indices preceding CTRCD development was performed 93 (IQR: 52-232) days before the detection of CTRCD. In the stage of CTRCD, the most significant ECG change was T-wave flattening in leads V3-V6 (12 patients, 80%). Additionally, QTa prolongation was observed in leads I and aVL (n = 10, 66%), leads II, III, and aVF (n = 9, 60%), and leads V3-V6 (n = 10, 73%). These ECG changes were not observed before the treatment but were detected mildly in the pre-CTRCD stage, which subsequently worsened in the CTRCD stage. CONCLUSIONS: This study indicated that T-wave changes and QTa prolongation may be useful as an early indicator before the onset of CTRCD in patients with DOX-induced cardiotoxicity.

Evaluation of oral anticoagulants in atrial fibrillation patients over 80 years of age with nonsevere frailty.

BACKGROUND: The safety and efficacy of an oral anticoagulant (OAC) treatment and the difference between direct OACs (DOACs) and warfarin in nonsevere frail elderly patients with AF are unclear. METHODS: This was a retrospective and observational study of 354 patients over 80 years of age with nonsevere frailty who were diagnosed with AF and treated with OACs. Nonsevere frailty was defined as a clinical frailty scale score of <7. Bleeding and thromboembolic events during the OAC treatment were followed up. RESULTS: Of 354 patients enrolled, 273 (77.1%) received DOACs and 81 (22.9%) received warfarin. Of 273 patients receiving DOACs, there were 210 (76.9%) prescribed with appropriate doses of DOACs. Of 81 warfarin-treated patients, 53 (65.4%) were prescribed an appropriate dose of warfarin. During a follow-up of 33.1 (14.0-51.0) months, 15 patients (1.5/100 person-years) had bleeding events and 10 (1.0/100 person-years) had thromboembolic events while on an OAC treatment. The incidence ratio of bleeding events in patients receiving DOACs was lower than that in those receiving warfarin (1.0/100 person-years vs 2.9/100 person-years, hazard ratio [HR]: 0.26, 95% confidence interval [CI]: 0.07-0.91, P = .036). There was no significant difference in the incidence of thromboembolic events between the DOAC and warfarin treatment groups (0.88/100 person-years vs 1.4/100 person-years, HR: 0.63, 95% CI: 0.16-2.57, P = .52). CONCLUSIONS: OACs are substantially safe and effective for preventing thromboembolic events in nonsevere frail patients over 80 years of age. Particularly, DOACs can be used more safely than warfarin.

Assessment of the bleeding risk of anticoagulant treatment in non-severe frail octogenarians with atrial fibrillation.

BACKGROUND: Physicians estimate the frailty in elderly patients with atrial fibrillation (AF) to aid in the decision making with respect to oral anticoagulant (OAC) therapy. There are limited data on the safety of OAC therapy in non-severe frail elderly patients. We evaluated the risk factors of bleeding among non-severe frail octogenarians with AF taking OACs. METHODS: Among 430 consecutive AF patients aged 80 years and over with non-severe frailty, we enrolled 346 patients [167 men, 83.7 (81.0-85.0) years] who were newly initiated on OACs: dabigatran, rivaroxaban, apixaban, edoxaban, or warfarin. To measure the frailty, the clinical frailty scale (CFS) was used. Non-severe frailty was defined as a CFS score of <7. The clinical factors were compared between the patients with and without bleeding during the OAC therapy. RESULTS: Out of the 346 patients enrolled, 266 (76.9%) received direct OACs (DOACs) and 80 (23.1%) warfarin. Of the 266 patients receiving DOACs, there were 204 (76.7%) prescribed appropriately adjusted-dose DOACs based on the approved Japanese recommendations. Of the 80 warfarin-treated patients, 52 (65.0%) were prescribed appropriately adjusted-dose warfarin. During a follow-up of 32.7 (14.0-51.0) months, bleeding events were detected in 59 patients (17.1%). Among the clinical factors, a multivariate analysis found that having a low body mass index (BMI) (<18.5kg/m2) was associated with the development of bleeding [hazard ratio (HR): 3.26, 95% confidence interval (CI): 1.65-6.50, p<0.01)]. Moreover, having a low BMI remained an independent risk factor for bleeding in the patients treated with appropriately adjusted-dose OACs (HR: 2.17, 95% CI: 1.01-4.70, p=0.048). CONCLUSIONS: In non-severe frail octogenarians with AF taking OACs, having a low BMI was the most significant factor associated with the development of bleeding.

Bleeding with oral anticoagulant dabigatran is highly associated with occult cancers in atrial fibrillation patients.

AIM: The aim of this study was to examine cancer and bleeding in atrial fibrillation patients administered with dabigatran. MATERIALS & METHODS: This study enrolled 509 consecutive nonvalvular atrial fibrillation patients who received dabigatran. The mean administration period was 14.8 ± 15.7 months. We investigated the prevalence and new development of cancers. Further, the relation between cancer and adverse events was evaluated. RESULTS: In the 509 patients, major bleeding occurred in 2.6% and dyspepsia in 8.4%. Further, 16.9% patients had a history of cancer and 3.9% developed new cancers. These adverse events developed in 45% patients who developed new cancers. The cancer (hazard ratio: 6.30; p = 0.003) was a significant predictor of major bleeding. CONCLUSION: Bleeding was associated with the presence of cancer.