Association between left atrial reverse remodeling and maintenance of sinus rhythm after catheter ablation of persistent atrial fibrillation.

The success rate of catheter ablation of persistent atrial fibrillation (AF) is not satisfactory, for reasons that are unclear. The purpose of this study was to examine the relationship between left atrial reverse remodeling after ablation and recurrence of AF in patients with persistent AF. One hundred and thirty-two patients with persistent AF were enrolled. Extensive encircling pulmonary vein isolation plus ablation of complex fractionated atrial electrograms was performed. Bepridil or amiodarone was prescribed for 3 months after ablation. All patients were studied by serial echocardiography and 24-h ambulatory electrocardiogram at baseline, for the day after ablation, and at 1-, 3-, and 6-month intervals after ablation. Recurrence of AF was observed in 42 patients at 2-year follow-up. The duration of AF (median 12 (IQR 6-37) vs 8 (IQR 5-17) months, p < 0.05), and early recurrence of AF (69 vs 26%, p < 0.05) after ablation were significantly different between the patients with AF recurrence and those without. The left atrial dimensions at 3 months (40 ± 6 vs 44 ± 6 mm, p < 0.001) and 6 months (40 ± 6 vs 44 ± 6 mm, p < 0.001) were significantly smaller than those just after ablation in the patients without AF recurrence. A 5% reduction from baseline in the left atrial dimension at 6 months after ablation was associated with freedom from late AF recurrence (p < 0.05). Left atrial reverse remodeling after ablation of persistent AF was associated with freedom from late recurrence of AF.

A Decision Tree-Based Survival Analysis of Patients with a History of Inappropriate Implantable Cardioverter-Defibrillator Therapy.

Implantable cardioverter-defibrillators (ICDs) improve survival in patients who are at risk of sudden death. However, inappropriate therapy is commonly given to ICD recipients, and this situation may be associated with an increased risk of death. This study aimed to construct a risk stratification scheme by using decision tree analysis in patients who received inappropriate ICD therapy.Mortality was calculated from a retrospective data analysis of a multicenter cohort involving 417 ICD recipients. Inappropriate therapy was defined as therapy for nonventricular arrhythmias, including sinus tachycardia, supraventricular tachycardia, atrial fibrillation/flutter, oversensing, and lead failure. Inappropriate therapy included antitachycardia pacing, cardioversion, and defibrillation. The prognostic factors were identified by a Cox proportional hazards regression analysis, and we constructed a decision tree.During an average follow-up of 5.2 years, 48 patients (12%) had all-cause death. A multivariate Cox hazard model revealed that the age (hazard ratio [HR] 1.06, P < 0.001), ln B-type natriuretic peptide (BNP) (HR 1.47, P = 0.02), nonsinus rhythm at implantation (HR 2.70, P < 0.05), and inappropriate therapy occurring during sedentary/awake conditions (HR 3.51, P = 0.001) correlated with an increased risk of mortality. An inappropriate therapy due to abnormal sensing (HR 0.16, P = 0.04) decreased the risk of mortality. Furthermore, a decision tree analysis stratified the patients well by using 4 covariates: BNP, activity at the time of inappropriate therapy, mechanism of inappropriate therapy, and baseline rhythm at ICD implantation (log-rank test, P < 0.0001).We identified the predictors of mortality in inappropriate ICD therapy recipients and constructed a risk stratification scheme by using decision tree analysis.

The seamless integration of three-dimensional rotational angiography images into electroanatomical mapping systems to guide catheter ablation of atrial fibrillation.

It is important to visually confirm radiofrequency ablation lesions during atrial fibrillation (AF) ablation for procedural efficiency, which requires the integration of a three-dimensional (3D) left atrial image reconstructed from computed tomography (CT) or a magnetic resonance imaging. However, an EP Navigator allows seamless integration of 3D anatomy obtained through 3D rotational angiography (3D-ATG) into an electroanatomical mapping system. We hypothesized that 3D-ATG can be used during AF ablation while significantly reducing the effective dose (ED) and without compromising image morphology compared to a 3D-CT image. Organ dose was measured at 37 points with a radiophotoluminescence glass dosimeter inserted in an anthropomorphic Rando Phantom. The ED was calculated by multiplying the organ dose by the tissue weighting factor. The dose-area product (DAP)-to-ED conversion factor was calculated by measuring the DAP during radiation exposure. The ED for the CT examination was estimated from the dose-length product with a conversion factor of 0.014. ED was calculated from DAP measurements in 114 patients undergoing AF ablation using 3D-ATG. The DAP-to-ED conversion factor for 3D-ATG was 2.4 × 10-4 mSv/mGy cm2 in our hospital. The mean DAP for all patients was 7777 ± 1488 mGy cm2 for the 3D-ATG of the left atrium. The corresponding ED for 3D-ATG was 1.9 ± 0.4 mSv. The ED for CT examinations was 13.6 ± 4.2 mSv (P < 0.001). 3D-ATG can be used during AF ablation while significantly reducing the ED and without compromising image morphology.

Effect of Anemia on Cardiovascular Hemodynamics, Therapeutic Strategy and Clinical Outcomes in Patients With Heart Failure and Hemodynamic Congestion.

BACKGROUND: We investigated the effect of anemia on cardiovascular hemodynamics, therapeutic strategies and clinical outcomes in heart failure (HF) patients.Methods and Results:We divided 198 consecutive HF patients who underwent right heart catheterization before in-hospital HF treatment into 2 groups according to the presence or absence of hemodynamic congestion (HC: mean pulmonary capillary wedge pressure ≥15 mmHg and/or mean right atrial pressure ≥10 mmHg). The hemoglobin level correlated with the cardiac index (CI) and systemic vascular resistance index (SVRI) (r=-0.34 and 0.42, P<0.05, respectively), and was the strongest contributor of SVRI only in the HC group. Anemic patients more frequently required intravenous inotropic support despite having higher CI and lower SVRI than non-anemic patients in the HC group. The novel hemodynamic subsets based on mean right atrial pressure and estimated left ventricular stroke work index but not Forrester subsets appropriately predicted the need for intravenous inotropic support. The probability of hospitalization for worsening HF during 2-year follow-up period was significantly higher in anemic patients than in non-anemic patients in the HC group. CONCLUSIONS: Anemia had a direct effect on cardiovascular hemodynamics and thus can confound therapeutic planning in HF patients with HC. The novel hemodynamic subsets can be applied in daily clinical practice regardless of the presence or absence of anemia.

Circumstances and outcomes of out-of-hospital cardiac arrest in elementary and middle school students in the era of public-access defibrillation.

BACKGROUND: Circumstances and outcomes of out-of-hospital cardiac arrest (OHCA) in elementary and middle school students while at school in the era of public-access defibrillation are unknown. METHODS AND RESULTS: We conducted a nationwide hospital-based survey of elementary and middle school students who had had OHCA of cardiac origin and received prehospital resuscitation in 2005-2009. Among 58 cases recruited, 90% were witnessed by bystanders; 86% had ventricular fibrillation as the initial rhythm; 74% were resuscitated by bystanders; 24% were defibrillated by bystanders; 55% occurred at school; 66% were exercise-related; 48% were followed up before the event; 67% had structural heart disease. In total, 53% of overall patients and 79% of those initially defibrillated by bystanders had a favorable neurological outcome. Patients were more likely to be defibrillated by bystanders (38% vs. 8%, P=0.012) and had a more favorable neurological outcome in schools (69% vs. 35%, P=0.017) than in other locations. The majority of arrests in schools were exercise-related (84% vs. 42%, P=0.001), occurred at sports venues, and students were resuscitated by teachers; half of the cases at school occurred in patients with a pre-event follow-up. CONCLUSIONS: After OHCA, children were more likely to be defibrillated by bystanders and had a better outcome in schools than in other locations, which may be relevant to the circumstances of events.

Hyperemic myocardial blood flow in patients with atrial fibrillation before and after catheter ablation: A dynamic stress CT perfusion study.

BACKGROUND: Atrial fibrillation (AF) patients without coronary artery stenosis often show clinical evidence of ischemia. However myocardial perfusion in AF patients has been poorly studied. The purposes of this study were to investigate altered hyperemic myocardial blood flow (MBF) in patients with AF compared with risk-matched controls in sinus rhythm (SR), and to evaluate hyperemic MBF before and after catheter ablation using dynamic CT perfusion. METHODS: Hyperemic MBF was quantified in 87 patients with AF (44 paroxysmal, 43 persistent) scheduled for catheter ablation using dynamic CT perfusion, and compared with hyperemic MBF in 87 risk-matched controls in SR. Follow-up CT after ablation was performed in 49 AF patients. RESULTS: Prior to ablation, hyperemic MBF of patients in AF during the CT (1.29 ± 0.34 ml/mg/min) was significantly lower than in patients in SR (1.49 ± 0.26 ml/g/min, p = 0.002) or matched controls (1.65 ± 0.32 ml/g/min, p < 0.001); no significant difference was seen between patients in SR during the CT and matched controls (vs. 1.50 ± 0.31 ml/g/min, p = 0.815). In patients in AF during the pre-ablation CT (n = 24), hyperemic MBF significantly increased after ablation from 1.30 ± 0.35 to 1.53 ± 0.17 ml/g/min (p = 0.004); whereas in patients in SR during the pre-ablation CT (n = 25), hyperemic MBF did not change significantly after ablation (from 1.46 ± 0.26 to 1.49 ± 0.27 ml/g/min, p = 0.499). CONCLUSION: In the current study using stress perfusion CT, hyperemic MBF in patients with AF during pre-ablation CT was significantly lower than that in risk-matched controls, and improved significantly after restoration of SR by catheter ablation, indicating that MBF abnormalities in AF patients are caused primarily by AF itself.

Brain magnetic resonance imaging and cognitive alterations after ablation in patients with atrial fibrillation.

Catheter ablation is an important non-pharmacological intervention for atrial fibrillation (AF), but its effect on the incidence of asymptomatic cerebral emboli and long-term effects on cognitive function remain unknown. We prospectively enrolled 101 patients who underwent AF ablation. Brain magnetic resonance imaging (MRI) (72 patients) and neuropsychological assessments (66 patients) were performed 1-3 days (baseline) and 6 months after ablation. Immediately after ablation, diffusion-weighted MRI and 3-dimensional double inversion recovery (3D-DIR) detected embolic microinfarctions in 63 patients (87.5%) and 62 patients (86.1%), respectively. After 6 months, DIR lesions disappeared in 41 patients. Microbleeds (MBs) increased by 17%, and 65% of the de novo MBs were exactly at the same location as the microinfarctions. Average Mini-Mental State Examination scores improved from 27.9 ± 2.4 to 28.5 ± 1.7 (p = 0.037), and detailed neuropsychological assessment scores showed improvement in memory, constructional, and frontal lobe functions. Ejection fraction, left atrial volume index and brain natriuretic peptide level improved from baseline to 3-6 months after ablation. Despite incidental microemboli, cognitive function was preserved 6 months after ablation.

Carvedilol and bisoprolol as initial therapy for adult hypertension without compelling indications.

Although beta blockers have been used as initial therapy for ischemic heart diseases and heart failure, the beneficial effects of beta blockers are controversial compared with other antihypertensive agents as initial therapy for hypertension without compelling indications. Moreover, atenolol has been most commonly used with beta blockers. The objective of the present systematic review associated with the Japanese Society of Hypertension (JSH) 2019 Hypertension Guideline (Clinical Question 6) was to assess the outcomes (cardiocerebrovascular mortality, total cause mortality, hypotension, bradycardia, other adverse effects, and changes in systolic blood pressure (SBP)) of currently used carvedilol and bisoprolol as initial therapy for adult hypertension without compelling indications. Two independent systematic reviewers searched randomized controlled trials (RCTs) up to October 2017 in the Cochrane Hypertension Specialized Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE Ovid, EMBASE Ovid, and ClinicalTrials.gov. Finally, eight RCTs with 2494 participants were identified to meet our inclusion criteria. There were no RCTs in which cardiocerebrovascular mortality, total cause mortality, hypotension, and bradycardia were assessed between carvedilol or bisoprolol and placebo. SBP-lowering effects were significantly increased for bisoprolol compared with placebo. Here, 50 mg carvedilol significantly reduced SBP compared with placebo, whereas 12.5 mg or 25 mg did not. Regarding adverse effects, no differences were noted between carvedilol and placebo (two RCTs, 286 participants, moderate certainly evidence). In conclusion, current evidence does not support carvedilol or bisoprolol as first-line therapy for adult hypertension without compelling indications.

Predictors of confirmatory test results for the diagnosis of primary hyperaldosteronism in hypertensive patients with an aldosterone-to-renin ratio greater than 20. The SHRIMP study.

It remains unknown which surrogate markers can predict diagnostic test results for primary hyperaldosteronism (PA). The Secondary Hypertension Registry Investigation in Mie Prefecture (SHRIMP) study has sequentially and prospectively recruited 128 patients with hypertension with an aldosterone-to-renin ratio (ARR) greater than 20, evaluated the differences among essential hypertension (EHT), idiopathic hyperaldosteronism (IHA), and aldosterone-producing adenoma (APA), and analyzed the predictors for the confirmatory tests. The patients underwent saline-loading, captopril-challenge, and upright furosemide-loading tests. Carotid, renovascular, and cardiac echography, brachial ankle pulse wave velocity (baPWV), endothelial function, nocturnal blood pressure decline, and the apnea hypopnea index were evaluated. Multivariate regression analyses showed that the plasma aldosterone concentration (PAC) at screening was a strong predictor of the saline and captopril test results. The plasma renin activity (PRA) at screening, urine ß2-microglobulin, and left ventricular mass index (LVMI) were independent predictors for the captopril test. The estimated saline PAC and captopril 60 and 90 min ARRs predicted by the equations were highly correlated with the real values. The ROC curve analysis showed PAC at screening among each of predictors for the diagnostic tests and PAC after the saline-loading test had the highest diagnostic abilities of APA. Patients with IHA were older and had glucose intolerance and increased U-Alb/gCre and resistive indices. In patients with APA, the levels of U-Alb/gCre and urine ß2-microglobulin were increased, and levels of insulin and the HOMA-IR were decreased. In conclusion, our proposed equations may be useful for estimating saline PAC and captopril ARR. Diagnostic predictors may differ for each confirmatory test.

Acute pulmonary hemorrhage during atrial fibrillation HotBalloon ablation.

A 64-year-old man with an atrial septal defect was referred for HotBalloon ablation of symptomatic drug-resistant paroxysmal atrial fibrillation. Pulmonary vein (PV) isolation was achieved using a SATAKE HotBalloon ablation system, which was inserted into the left atrium through the deflectable guiding sheath via the atrial septal defect. During ablation of the right superior pulmonary vein carina, the HotBalloon dropped to the left atrium. Hemoptysis and respiratory failure was then observed, and the patient was intubated and controlled under ventilator. The computed tomography identified a pseudoaneurysm developed on the right superior PV, with massive hemorrhagic alveolar flooding.

Twitching of the Pacemaker Pocket Induced by Radiofrequency Energy Delivery to the Cavotricuspid Isthmus.

An 82-year-old man with a permanent pacemaker (PM) implanted for sick sinus syndrome complained of palpitation due to paroxysmal atrial fibrillation and flutter. During extensive pulmonary vein isolation, the atrial lead was dislodged to the level of the tricuspid annulus. Radiofrequency energy delivery to the cavotricuspid isthmus reproducibly caused twitching of the PM pocket. The atrial lead was repositioned to the right atrial appendage, PM check revealed no functional change in the PM or lead performance. This is the first reported case of twitching of the PM pocket due to electromagnetic interference.

A novel method for the quantitative evaluation of diurnal respiratory instability in patients with heart failure: A pilot study.

BACKGROUND: There is no established method to quantitatively measure the presence and the severity of respiratory instability (RI). The purpose of this pilot study was to propose a novel index of diurnal RI as a surrogate measure of clinical severity of heart failure (HF). METHODS AND RESULTS: We prospectively enrolled 60 patients with symptomatic HF [70±14 years, 75% male, and New York Heart Association (NYHA) functional classes II-IV] who underwent right heart catheterization (RHC), and recorded diurnal respiration using a nasal pressure sensor during bed rest while awake within 2 days before or after RHC. Non-uniformity of the breath-by-breath respiratory slopes during 15min calculated as the ratio of peak expiratory amplitude to corresponding peak-to-peak interval was assessed by histogram-based frequency distribution measurement, and was defined as the "RI-index". The RI-index was significantly different among NYHA functional classes and was highest in NYHA class IV. The presence of atrial fibrillation (ß coefficient: 0.300, p=0.01) and stroke volume index (ß coefficient: -0.462, p<0.01) were independently associated with RI index among hemodynamic parameters. Furthermore, the high RI index above the median value was the independent predictor of the composite outcome of death from any cause, a life-threatening arrhythmia, and an unplanned hospitalization for worsening HF. CONCLUSIONS: The RI index stratified functional severity of HF well, and was a significant independent predictor of poor outcomes.

Combined Assessment of Stress Myocardial Perfusion Cardiovascular Magnetic Resonance and Flow Measurement in the Coronary Sinus Improves Prediction of Functionally Significant Coronary Stenosis Determined by Fractional Flow Reserve in Multivessel Disease.

BACKGROUND: Recent studies using stress-rest perfusion cardiovascular magnetic resonance (CMR) demonstrated a close correlation between myocardial ischemia and reduced fractional flow reserve (FFR). However, its diagnostic concordance may be reduced in patients with multivessel disease. We sought to evaluate the concordance of adenosine stress-rest perfusion CMR for predicting reduced FFR, and to determine the additive value of measuring global coronary flow reserve (CFR) in the coronary sinus in multivessel disease. METHODS AND RESULTS: Ninety-six patients with angiographic luminal narrowing >50% underwent comprehensive CMR study and FFR measurements in 139 coronary vessels. FFR <0.80 was considered hemodynamically significant. Global CFR was quantified as the ratio of stress-rest coronary sinus flow measured by phase-contrast cine CMR. In 25 patients with single-vessel disease, visual assessment of perfusion CMR yielded high diagnostic concordance for predicting flow-limiting stenosis, with the area under receiver operating characteristic curve of 0.93 on a per-patient basis. However, in 71 patients with multivessel disease, perfusion CMR underestimated flow-limiting stenosis, resulting in the reduced area under receiver operating characteristic curve of 0.74. When CFR of <2.0 measured in the coronary sinus was considered as global myocardial ischemia, combined assessment provided correct reclassifications in 7 patients with false-negative myocardial ischemia, and improved the diagnostic concordance to 92% sensitivity and 73% specificity with the area under receiver operating characteristic curve of 0.88 (95% confidence interval, 0.80%-0.97%, P=0.002). CONCLUSIONS: Visual analysis of stress-rest perfusion CMR has limited concordance with FFR in patients with multivessel disease. Multiparametric CMR integrating stress-rest perfusion CMR and flow measurement in the coronary sinus is useful for detecting reduced FFR in multivessel disease.

Three cases of vasospastic angina following catheter ablation of atrial fibrillation.

Pulmonary vein isolation is an effective treatment for patients with atrial fibrillation (AF).Although vasospastic angina (VSA) is not a common complication after ablation of AF, we report 3 cases of VSA following ablation of persistent AF. Two of the 3 patients felt chest pain following pulmonary vein isolation, and complex fractionated atrial electrogram ablations were performed. ST elevation in the inferior leads and atrioventricular block occurred because of severe coronary vasospasm. In the third patient, the electrocardiography monitor detected transient ST elevation within an hour after ablation. Treatment of VSA may be required following catheter ablation of AF.

Inappropriate implantable cardioverter defibrillator shocks-incidence, effect, and implications for driver licensing.

PURPOSE: Patients with implantable cardioverter defibrillators (ICDs) have an ongoing risk of sudden incapacitation that may cause traffic accidents. However, there are limited data on the magnitude of this risk after inappropriate ICD therapies. We studied the rate of syncope associated with inappropriate ICD therapies to provide a scientific basis for formulating driving restrictions. METHODS: Inappropriate ICD therapy event data between 1997 and 2014 from 50 Japanese institutions were analyzed retrospectively. The annual risk of harm (RH) to others posed by a driver with an ICD was calculated for private driving habits. We used a commonly employed annual RH to others of 5 in 100,000 (0.005%) as an acceptable risk threshold. RESULTS: Of the 4089 patients, 772 inappropriate ICD therapies occurred in 417 patients (age 61 ± 15 years, 74% male, and 65% secondary prevention). Patients experiencing inappropriate therapies had a mean number of 1.8 ± 1.5 therapy episodes during a median follow-up period of 3.9 years. No significant differences were found in the age, sex, or number of inappropriate therapies between patients receiving ICDs for primary or secondary prevention. Only three patients (0.7%) experienced syncope associated with inappropriate therapies. The maximum annual RH to others after the first therapy in primary and secondary prevention patients was calculated to be 0.11 in 100,000 and 0.12 in 100,000, respectively. CONCLUSIONS: We found that the annual RH from driving was far below the commonly cited acceptable risk threshold. Our data provide useful information to supplement current recommendations on driving restrictions in ICD patients with private driving habits.

Chronic Inflammatory Disease Is an Independent Risk Factor for Coronary Flow Velocity Reserve Impairment Unrelated to the Processes of Coronary Artery Calcium Deposition.

BACKGROUND: Chronic inflammatory disease (CID) is a complex multisystem disease characterized by chronic inflammation, which can lead to coronary microvascular dysfunction (CMD) and can also predispose to coronary artery calcium deposition, even in the absence of obstructive coronary artery disease. METHODS: Twenty-one patients with systemic lupus erythematosus (SLE; mean age, 60 ± 11 years), 21 patients with systemic sclerosis (SSc; mean age, 66 ± 11 years), 32 patients with rheumatoid arthritis (RA; mean age, 65 ± 9 years), and 23 control subjects with comparable traditional risk factors for coronary artery disease (mean age, 65 ± 10 years) were prospectively enrolled in the outpatient clinic. All study participants underwent transthoracic Doppler-derived echocardiography for coronary flow velocity reserve (CFVR) measurement in the left anterior descending coronary artery; CFVR < 2.5 defined CMD. Coronary artery calcium score in the left anterior descending coronary artery was also assessed by computed tomography. RESULTS: None of study participants had obstructive coronary artery disease. The prevalence of CMD was 26% in the control group, 67% in the SLE group, 76% in the SSc group, and 63% in the RA group (P < .05, CID groups vs control group). CFVR was significantly lower in all three CID groups than in the control group (control group, 3.01 ± 0.72; SLE group, 2.23 ± 0.71; SSc group, 2.14 ± 0.54; RA group, 2.33 ± 0.62; P < .05, CID groups vs control group). In contrast, coronary artery calcium scores were similar in the four groups and had no relation to CMD. The odds ratios for CMD in patients with SLE, SSc, and RA were 16.70, 25.78, and 8.44 (P < .05) after adjusting for age, body mass index, the presence or absence of anemia, and hemoglobin level. Multiple linear regression analysis showed that only the presence of CID was independently associated with reduced CFVR among all study participants. CONCLUSIONS: CID strongly contributes to CMD identified by qualitative evaluation of CFVR independently of traditional coronary risk factors of atherosclerosis but does not predispose to coronary artery calcification.

A combination of two simultaneous tachycardias in the right atrium close to the atrio-ventricular node and within the coronary sinus in a post-operative cor triatriatum patient.

A 71-year-old male was referred to another hospital for dizziness. A bradycardia -tachycardia syndrome and Cor triatriatum were detected, and an operation to resect the membrane in the left atrium and implant a pacemaker epicardially was performed. However, no suitable site could be found on either atria and therefore, a single chamber ventricular pacemaker was implanted. In the electrophysiological study performed in our hospital, we could not detect any atrial potentials in either atria, excluding the region close to the His bundle (HB) and within coronary sinus (CS), in spite of extensive catheter mapping. A regular atrial rhythm with a cycle length of 820 ms, which was synchronous with the rate of the QRS complex on the surface ECG, was recorded only at the HB. Meanwhile, the CS catheter recording exhibited regular focal activity with a cycle length of 150 ms, and this focal activity did not conduct to the atrium close to the HB. Furthermore, this activity was dissociated from the ventricular activity recorded from the CS catheter. During an isoproterenol infusion, an atrial tachycardia with a cycle length of 380 ms was recorded only at the HB, and the twelve-lead ECG exhibited a regular tachycardia with the same cycle length as this tachycardia. Meanwhile, the focal activity within the CS persisted without any change in the cycle length. These findings suggested that there was dissociation between the right atrium (RA) and CS. Furthermore, partial atrial standstill was observed in both atria, excluding the RA close to the atrio-ventricular (AV) node and area within the CS. These rare electrophysiological features were considered to play an important role in the genesis of a simultaneous combination of the two tachycardias at their respective sites.