Yoshihisa Naruse

Concomitant obstructive sleep apnea increases the recurrence of atrial fibrillation following radiofrequency catheter ablation of atrial fibrillation: clinical impact of continuous positive airway pressure therapy.

BACKGROUND Recent studies have suggested an emerging link between obstructive sleep apnea (OSA) and atrial fibrillation (AF). Patients with OSA are less likely to remain in sinus rhythm after radiofrequency catheter ablation of AF. OBJECTIVE To evaluate the efficacy of appropriate treatment with continuous positive airway pressure (CPAP) on recurrences of AF after ablation. METHODS This study prospectively included 153 patients (128 men; 60 ± 9 years) who underwent extensive encircling pulmonary vein isolation for drug refractory AF. The standard overnight polysomnographic evaluation was performed 1 week after ablation, and the total duration and the number of central or obstructive sleep apnea or hypopnea episodes were examined. RESULTS Of 153 patients, 116 patients were identified as having OSA. Data regarding the use of CPAP and recurrences of AF were obtained in 82 patients. The remaining 34 patients with OSA were defined as the no-CPAP group. Polysomnography revealed no sleep-disordered breathing in 37 patients. During a mean follow-up period of 18.8 ± 10.3 months, 51 (33%) patients experienced AF recurrences after ablation. A Cox regression analysis revealed that the left atrial volume (hazard ratio [HR] 1.11; 95% confidence interval [CI] 1.01-1.23; P<.05), concomitant OSA (HR 2.61; 95% CI 1.12-6.09; P<.05), and usage of CPAP therapy (HR 0.41; 95% CI 0.22-0.76; P<.01) were associated with AF recurrences during the follow-up period. CONCLUSIONS Patients with untreated OSA have a higher recurrence of AF after ablation. Appropriate treatment with CPAP in patients with OSA is associated with a lower recurrence of AF.

Early repolarization is an independent predictor of occurrences of ventricular fibrillation in the very early phase of acute myocardial infarction.

Background—Recent evidence has linked early repolarization (ER) to idiopathic ventricular fibrillation (VF) in patients without structural heart disease. However, no studies have clarified whether or not there is an association between ER and the VF occurrences after the onset of an acute myocardial infarction (AMI). Methods and Results—This study retrospectively included 220 consecutive patients with an AMI (57 female; mean age, 69 ± 11 years) in whom the 12-lead ECGs before the AMI onset could be evaluated. The patients were classified on the basis of a VF occurrence within 48 hours after the AMI onset. Early repolarization was defined as an elevation of the QRS-ST junction of >0.1 mV from baseline in at least 2 inferior or lateral leads, manifested as QRS slurring or notching. Twenty-one (10%) patients had a VF occurrence within 48 hours of the AMI onset. A multivariate analysis revealed that ER (odds ratio [OR], 7.31; 95% confidence interval [CI], 2.21–24.14; P<0.01), a time from the onset to admission of <180 minutes (OR, 3.77; 95% CI, 1.13–12.59; P<0.05), and a Killip class greater than I (OR, 13.60; 95% CI, 3.43–53.99; P<0.001) were independent predictors of VF occurrences. As features of the ER pattern, a J-point elevation in the inferior leads, greater magnitude of the J-point elevation, notched morphology of the ER, and ER with a horizontal/descending ST segment, all were significantly associated with a VF occurrence. Conclusions—The presence of ER increased the risk of VF occurrences within 48 hours after the AMI onset.

Concomitant chronic kidney disease increases the recurrence of atrial fibrillation after catheter ablation of atrial fibrillation: A mid-term follow-up

BACKGROUND Chronic kidney disease (CKD) is often associated with atrial fibrillation (AF). However, its impact on the results of radiofrequency catheter ablation for AF has not been fully examined. OBJECTIVE The purpose of this study was to clarify the relationship between CKD and postcatheter ablation AF recurrence. METHODS The study included 221 patients with AF who underwent successful catheter ablation. The prevalence and characteristics of AF recurrences were determined. CKD was defined as an estimated glomerular filtration rate <60 mL/min/1.73 m(2). RESULTS After mean follow-up of 31.9 ± 7.6 months, 87 (39%) patients had AF recurrences. Multivariate Cox regression analysis revealed that CKD (hazard ratio [HR] 2.089, 95% confidence interval [CI] 1.292-3.378, P <.01) and left atrial volume (HR 1.009, 95% CI 1.002-1.017, P <.05) were independent predictors of AF recurrences. Among the 221 patients, 54 (24.4%) had CKD. Patients with CKD had a higher incidence of AF recurrences (57.4%) compared to the non-CKD patients (33.5%, P <.01). Compared with patients without CKD, patients with CKD were older (64 ± 11 years vs 58 ± 10 years, P <.001) and had a higher prevalence of hypertension (72% vs 53%, P <.05), larger left atrial volume (74.7 ± 29.4 mL vs 62.0 ± 26.0 mL, P <.01), and higher plasma B-type natriuretic peptide levels (129.6 ± 209.3 pg/mL vs 68.8 ± 91.0 pg/mL, P <.01). CONCLUSION The presence of CKD increased the risk of AF recurrences after catheter ablation. Multifactorial physiologic factors due to CKD may account for the higher prevalence of recurrent AF in patients with CKD than in those without.

The clinical impact of late gadolinium enhancement in Takotsubo cardiomyopathy: serial analysis of cardiovascular magnetic resonance images

BackgroundOur study aimed to investigate both the clinical implications of late gadolinium enhancement (LGE) by cardiovascular magnetic resonance (CMR) and the relation of LGE to clinical findings in patients with Takotsubo cardiomyopathy (TTC).MethodsWe evaluated 20 consecutive patients (2 men, 18 women; median age, 77 years; interquartile range [IQR] 67-82 years) who were admitted to our hospital with the diagnosis of TTC. CMR was performed within 1 week after admission, and follow-up studies were conducted 1.5 and 6 months later.ResultsIn 8 patients, CMR imaging during the sub-acute phase revealed LGE in the area matched with wall motion impairment. Cardiogenic shock was more frequently observed in patients with LGE than in those without LGE (38% vs 0%, p = 0.049). The patients with LGE needed a longer duration for ECG normalization and recovery of wall motion than did those without LGE (median 205 days, IQR [152-363] vs 68 days, [43-145], p = 0.005; 15 days, [10-185] vs 7 days, [4-13], p = 0.030, respectively). In 5 of these 8 patients, LGE disappeared within 45-180 days (170, IQR [56-180]) of onset. The patients with LGE remaining in the chronic phase had higher peak creatine kinase levels than did those without LGE (median 307 IU/L, IQR [264-460] vs 202 IU/L, [120-218], p = 0.017).ConclusionLGE by CMR in the sub-acute phase may be associated with the severity and prolonged recovery to normal of clinical findings in TTC.

Successful catheter ablation of bidirectional ventricular premature contractions triggering ventricular fibrillation in catecholaminergic polymorphic ventricular tachycardia with RyR2 mutation.

The subject of this report is a 38-year-old woman who often experienced syncope since childhood. Syncope occurred >10 times a year and was associated with convulsion during exercise and emotionally exciting situations. The patients 13-year-old daughter had also experienced frequent episodes of syncope and developed ventricular fibrillation (VF) during treadmill exercise testing that was successfully defibrillated with electric shock. Witnessing this situation, the patient also lost consciousness, with documented VF that was converted to sinus rhythm by cardiopulmonary resuscitation without electric defibrillation. Both the patient and her daughter were admitted to our hospital. We performed echocardiography, coronary angiography, and cardiac CT, the results of which revealed no structural heart disease. Resting 12-lead ECG did not indicate any abnormalities, including long-QT syndrome or Brugada syndrome. A signal-averaged ECG revealed no late potentials. Treadmill exercise testing easily induced bigeminal ventricular premature contractions (VPCs) with a right bundle branch block configuration and inferior axis (Figure 1A), and the exercise was terminated because of intolerable symptoms. Catecholamine stress test was started with administration of continuous intravenous infusion of epinephrine in a stepwise manner from 0.025 μg/kg per minute.1 During epinephrine infusion at a rate of 0.1 μg/kg per minute, multifocal VPCs (VPC #1, right bundle branch block configuration and superior axis; VPC #2, right bundle branch block configuration and inferior axis [the same VPC configuration as that induced during the treadmill exercise testing]; and VPC #3, left bundle branch block configuration and inferior axis) appeared, and VPC #1 following VPC #2 subsequently induced VF (Figure 1B). Figure 1. A , Twelve-lead ECG recording during treadmill exercise testing. Bigeminal ventricular premature contractions (VPCs) appeared during the second stage of the Bruce protocol. VPC morphology …

Prevalence and characteristics of asymptomatic excessive transmural injury after radiofrequency catheter ablation of atrial fibrillation.

BACKGROUND Even with a low energy setting, radiofrequency energy applications on the left atrial (LA) posterior wall may cause excessive transmural injury (ETI) during catheter ablation of atrial fibrillation (AF). OBJECTIVE The purpose of this study was to clarify the prevalence and characteristics of ETI. METHODS This study included 104 patients with AF who underwent extensive encircling pulmonary vein isolation (EEPVI) followed by an endoscopic examination (≤48 hours after EEPVI). EEPVI was performed under conscious sedation, and the ablation settings at the LA posterior wall were a maximum energy of 20 to 25 W and duration of ≤30 seconds. The ETI was defined as any injury that resulted from EEPVI, including esophageal damage or periesophageal nerve injury. RESULTS ETIs were found in 10 (9.6%) patients and were all asymptomatic; esophageal damage in 4 patients and periesophageal nerve injury in the remaining 6. All patients with ETI were below normal weight (body mass index [BMI] < 24.9 kg/m(2)), and consisted of 17% of those below normal weight. The procedural parameters such as the type of energy source, total duration of energy applications to the LA posterior wall, additional LA linear ablation, and biochemical markers were not related to the ETI. In the logistic multiadjusted model, the BMI (per 1 kg/m(2)) was the only independent predictor of ETI (odds ratio = 0.76; 95% confidence interval = 0.59 to 0.97, P < .05). CONCLUSION Asymptomatic ETIs were not rare even with a low energy setting in patients below normal weight. Tailored energy settings based on the patients BMI may be required when performing EEPVI.

Systematic Treatment Approach to Ventricular Tachycardia in Cardiac Sarcoidosis

Background—Fatal arrhythmia is commonly observed in cardiac sarcoidosis, but clinical effects of a systematic treatment approach are still uncertain. This study sought to describe both clinical and electrophysiological characteristics and outcomes of systematic treatment approach to ventricular tachycardia (VT) associated with cardiac sarcoidosis. Methods and Results—We enrolled 37 consecutive patients (11 men; age, 56±11 years) with a diagnosis of sustained VT associated with cardiac sarcoidosis. Clinical effects of a systematic treatment approach including medical therapy (both steroid and antiarrhythmic agents), in association with radiofrequency catheter ablation, were evaluated. All patients received antiarrhythmic agents, and 34 received steroid therapy. During a 39-month follow-up, 23 (62%) patients were free from any VT episodes with medical therapy. Multivariable Cox regression analyses revealed that the absence of gallium-67 myocardial uptake was an independent predictor for VT recurrence (hazard ratio, 7.51; 95% confidence interval, 1.65–34.26; P<0.01). Fourteen patients who experienced VT recurrences even while on drug therapy underwent radiofrequency catheter ablation. Electrophysiological study revealed that the mechanisms of VTs could be classified into 2 subgroups: Purkinje-related or scar-related VT. The QRS duration of VT was narrower in Purkinje-related than in scar-related VTs (157±23 versus 183±22 ms; P<0.05). After a 33-month follow-up subsequent to the radiofrequency catheter ablation, 6 of 14 patients experienced VT recurrence. The number of VTs sustained during electrophysiological study was higher in the patients with VT recurrence than in those without (3.7±1.4 versus 1.9±0.8; P<0.01). Conclusions—A systematic treatment approach to cardiac sarcoidosis with VT successfully suppressed VT recurrences in the majority of patients studied.

Effect of eplerenone on maintenance of sinus rhythm after catheter ablation in patients with long-standing persistent atrial fibrillation.

Several studies have demonstrated a relation between the rennin-angiotensin-aldosterone system and atrial fibrillation (AF), but there are no reports on the effect of eplerenone, a selective aldosterone blocker, on the prevention of AF recurrence after radiofrequency catheter ablation (RFCA). The aim of this study was to evaluate the effects of eplerenone on clinical outcomes after RFCA in patients with long-standing persistent AF. A total of 161 consecutive patients with long-standing persistent AF (sustained AF duration 1 to 20 years, mean 3.4 ± 3.8) who underwent RFCA were investigated. Eplerenone was used in 55 patients and not used in the remaining 106 patients. Other conventional pharmacologic agents, including angiotensin-converting enzyme inhibitors or angiotensin type 1 receptor blockers, were used equally in the 2 groups. After 24 months of follow-up, 47% of the patients were free from AF recurrence. The rate of freedom from AF recurrence was significantly greater in the eplerenone group (60%) than in the noneplerenone group (40%) (p = 0.011). By univariate analysis, the duration of sustained AF (p <0.001), left atrial diameter (p = 0.010), left atrial volume index (p = 0.017), and early AF recurrence (p <0.001) were significantly associated with AF recurrence, and the use of eplerenone was associated with maintenance of sinus rhythm after RFCA (p = 0.022). Multivariate Cox regression analysis showed that longer duration of sustained AF (>3 years) (p <0.001) and early AF recurrence (p <0.001) were significantly associated with AF recurrence, and only eplerenone therapy significantly improved maintenance of sinus rhythm (p = 0.017). In conclusion, eplerenone significantly improved maintenance of sinus rhythm after RFCA in patients with long-standing persistent AF.

Triple Antithrombotic Therapy Is the Independent Predictor for the Occurrence of Major Bleeding Complications Analysis of Percent Time in Therapeutic Range

Background—Triple antithrombotic therapy increases the risk of bleeding events in patients undergoing percutaneous coronary intervention. However, it remains unclear whether good control of percent time in therapeutic range is associated with reduced occurrence of bleeding complications in patients undergoing triple antithrombotic therapy. Methods and Results—This study included 2648 patients (70±11 years; 2037 men) who underwent percutaneous coronary intervention with stent in the Ibaraki Cardiovascular Assessment Study registry and received dual antiplatelet therapy with or without warfarin. Clinical end points were defined as the occurrence of major bleeding complications (MBC), major adverse cardiac and cerebrovascular event, and all-cause death. Among these 2648 patients, 182 (7%) patients received warfarin. After a median follow-up period of 25 months (interquartile range, 15–35 months), MBC had occurred in 48 (2%) patients, major adverse cardiac and cerebrovascular event in 484 (18%) patients, and all-cause death in 206 (8%) patients. Multivariable Cox regression analysis revealed that triple antithrombotic therapy was the independent predictor for the occurrence of MBC (hazard ratio, 7.25; 95% confidence interval, 3.05–17.21; P<0.001). The time in therapeutic range value did not differ between the patients with and without MBC occurrence (83% [interquartile range, 50%–90%] versus 75% [interquartile range, 58%–87%]; P=0.7). However, the mean international normalized ratio of prothrombin time at the time of MBC occurrence was 3.3±2.1. Triple antithrombotic therapy did not have a predictive value for the occurrence of all-cause death (P=0.1) and stroke (P=0.2). Conclusions—Triple antithrombotic therapy predisposes patients to an increased risk of MBC regardless of the time in therapeutic range.

Early Repolarization Increases the Occurrence of Sustained Ventricular Tachyarrhythmias and Sudden Death in the Chronic Phase of an Acute Myocardial Infarction

Background—We recently showed that the presence of early repolarization (ER) increases the risk of ventricular fibrillation occurrences in the early phase of acute myocardial infarction (AMI). This study aimed to clarify whether an association exists between ER and occurrences of ventricular tachyarrhythmias or sudden death in the chronic phase of AMI. Methods and Results—This study retrospectively enrolled 1131 patients (67±12 years; 862 men) with AMIs surviving 14 days post-AMI. The primary end point was the occurrence of sustained ventricular tachyarrhythmias or sudden death >14 days after the AMI onset. We evaluated the presence of ER from the predischarge ECG (mean 10±3 days post-AMI). ER was defined as an elevation of the terminal portion of the QRS complex of >0.1 mV in inferior or lateral leads. After a median follow-up of 26.2 months, 26 patients had an episode of ventricular tachyarrhythmias or sudden death. A multivariable Cox regression analysis revealed the presence of ER (hazard ratio, 5.37; 95% confidence interval, 2.27–12.69; P<0.001), Killip class on admission of >I (hazard ratio, 2.75; 95% confidence interval, 1.24–6.07; P=0.013), and a left ventricular ejection fraction of <35% (hazard ratio, 11.83; 95% confidence interval, 5.16–27.13; P<0.001) were significantly associated with event occurrences. As features of the ER pattern, ER in the inferior leads, high-amplitude ER, a notched morphology, and ER without ST-segment elevation were associated with an increased risk of event occurrences. Conclusions—ER observed at a mean of 10 days post-AMI may be a marker for a subsequent risk of ventricular tachyarrhythmias or sudden death.