Predictors of long-term survival in Japanese patients with heart failure with reduced ejection fraction (HFrEF) treated with cardiac resynchronization therapy-defibrillators (CRT-D).

BACKGROUND: Reports on the factors predicting long-term survival of CRT-D cases from Western countries are increasing, however, those from Asia including Japan are still sparse. We aimed to clarify the factors predicting long-term survival of Japanese CRT-D cases. METHODS: We retrospectively analyzed consecutive 133 patients who underwent CRT-D implantation between 2006 and 2021. We compared clinical factors between patients who died within 5 years after implantation (short-survival group: n = 31) and who had survived for more than 5 years (long-survival group: n = 36) after implantation. RESULTS: Major underlying heart diseases were dilated cardiomyopathy (45%) and ischemic heart disease (12%). There was no difference between the short-survival group and the long-survival group in incidence of CLBBB (32% vs. 30%), whereas CRBBB was more common in the short-survival group (26% vs. 0%, p = .004). Mechanical dyssynchrony at implantation was more frequent in the long-survival group (48% vs. 78%, p = .02). The incidence of response to CRT at 1 year after implantation was higher in long-survival group (19% vs. 50%, p = .02). Multiple logistic regression analysis identified NYHA class, mechanical dyssynchrony at implantation, and response at one year as predictors of long-term survival. CONCLUSIONS: In Japanese CRT-D cases, lower NHYA class, preexisting mechanical dyssynchrony, and 1-year response to CRT predict long-term survival.

A Cyber-Physical Framework for Optimal Coordination of Connected and Automated Vehicles on Multi-Lane Freeways.

Uncoordinated driving behavior is one of the main reasons for bottlenecks on freeways. This paper presents a novel cyber-physical framework for optimal coordination of connected and automated vehicles (CAVs) on multi-lane freeways. We consider that all vehicles are connected to a cloud-based computing framework, where a traffic coordination system optimizes the target trajectories of individual vehicles for smooth and safe lane changing or merging. In the proposed framework, the vehicles are coordinated into groups or platoons, and their trajectories are successively optimized in a receding horizon control (RHC) approach. Optimization of the traffic coordination system aims to provide sufficient gaps when a lane change is necessary while minimizing the speed deviation and acceleration of all vehicles. The coordination information is then provided to individual vehicles equipped with local controllers, and each vehicle decides its control acceleration to follow the target trajectories while ensuring a safe distance. Our proposed method guarantees fast optimization and can be used in real-time. The proposed coordination system was evaluated using microscopic traffic simulations and benchmarked with the traditional driving (human-based) system. The results show significant improvement in fuel economy, average velocity, and travel time for various traffic volumes.

Clinical impact of nocturnal ventricular tachyarrythmias in electrical storm.

BACKGROUND: The incidence of electrical storm (ES) is significantly higher during the daytime. However, the association between nocturnal ventricular tachyarrythmias during ES and prognosis remains unclear. Therefore, this study aimed to investigate the clinical characteristics and outcomes of ES with midnight ventricular tachyarrythmias. METHODS: We included 48 consecutive patients who had an implantable cardioverter-defibrillator or cardiac resynchronization therapy defibrillator implanted between 2010 and 2020 and those who had experienced the onset of an out-of-hospital ES episode. According to the midnight (0:00 a.m.-6:00 a.m.) occurrence of ventricular arrythmia events consisting of ventricular tachycardia (VT) and ventricular fibrillation (VF), we divided them into two groups (with-midnight group: n = 27, without-midnight group: n = 21). The clinical characteristics and outcomes of the two groups were compared. RESULTS: The patients in the with-midnight group were mostly males, had longer QRS duration, and longer corrected QT-interval than those in the without-midnight group (p < .05). The incidence of all-cause death, especially heart failure death, was higher in the with-midnight group than in the without-midnight group (p < .01). Multivariate analysis showed that the presence of midnight VT/VF during ES was the only independent risk factors for heart failure death (HR = 18.9, 95%CI = 1.98-181, p = .011). CONCLUSIONS: The presence of midnight VT/VF during ES might be associated with the poor prognosis. The loss of a sympathetic circadian pattern of VT/VF distribution during ES might suggest advanced stages of the cardiac disease.

The Risk of Ventricular Tachyarrhythmias in Patients with Antimitochondrial Antibodies-Related Noncardiac Diseases.

Antimitochondrial antibodies (AMA) are serum autoantibodies specific to primary biliary cholangitis and are linked to myopathy and myocardial damage; however, the presence of AMA as a risk factor for ventricular tachyarrhythmias (VTs) has remained unknown. This study aimed to elucidate whether the presence of AMA-related noncardiac diseases indicates VTs risk.This cohort study enrolled 1,613 patients (883 females) who underwent AMA testing to assess noncardiac diseases. The incidence of VTs and supraventricular tachyarrhythmias (SVTs) from a year before the AMA testing to the last visit of the follow-up were retrospectively investigated as primary and secondary objectives. Using propensity score matching, we extracted AMA-negative patients whose covariates were matched to those of 152 AMA-positive patients. In this propensity score-matched cohort, the incidence of VTs and SVTs in the AMA-positive patients were compared with that in AMA-negative patients.The AMA-positive patients had higher estimated cumulative incidence (log-rank, P = 0.013) and prevalence (5.9% versus 0.7%, P = 0.020) of VTs than the AMA-negative patients. The presence of AMA was an independent risk factor for VTs (hazard ratio, 4.02; 95% CI, 1.44-20.01; P = 0.005). Meanwhile, AMA were associated with atrial flutter and atrial tachycardia development. In AMA-positive patients, VTs were associated with male sex, underlying myopathy, high creatine kinase levels, presence of chronic heart failure or ischemic heart disease, left ventricular dysfunction, presence of SVTs, and the electrocardiographic parameters indicating atrial disorders.The presence of AMA-related noncardiac diseases is an independent risk factor for VTs.

Efficacy of antitachycardia pacing alert by remote monitoring of implantable cardioverter-defibrillators for out-of-hospital electrical storm.

BACKGROUND: Remote monitoring (RM) has been shown to reduce all-cause mortality in patients with implantable cardioverter-defibrillators or cardiac resynchronization therapy defibrillators (ICD/CRT-D). Not all devices transmit an alert for antitachycardia pacing (ATP) therapy, and it is unknown whether differences of RM alert affect the outcomes of electrical storm (ES). METHODS: We enrolled 42 patients with ICD/CRT-D whose out-of-hospital ES were detected by RM between 2013 and 2020. We divided their 54 episodes into two groups (ATP-alert-on; 22, ATP-alert-off; 32), and clinical outcomes were compared between the two groups. RESULTS: In 35 of 54 episodes of ES, ventricular tachycardia (VT) could be terminated within 24 h of ES onset just by ATP (ATP-alert-on: 14, ATP-alert-off: 21); however, many patients subsequently received shock delivery for VT. Among the 35 episodes, only in ATP-alert-on group, seven patients were prompted to visit our hospital without ICD shock through confirmation of ES by ATP-alert. Episodes that led to shock delivery 24 h or longer after the ES onset were significantly less common in the ATP-alert-on group (ATP-alert-on: 1/14, ATP-alert-off: 9/21, p = .03). Although there were no significant differences in the number of shock deliveries between episodes in the two groups, the number of ATP deliveries were significantly fewer in the ATP-alert-on group (12[7-26] vs. 29[16-53] in ATP-alert-off group, p = .03). Multivariate logistic regression analyses showed that the only ATP-alert significantly reduced ATP deliveries (HR = 0.14, 95%CI = 0.04-0.57, p = .003). CONCLUSION: Remote monitoring with an ATP-alert function during electrical storm may reduce appropriate ICD therapy through prompting early review.

Accentuation of J waves by intracoronary administration of multiple agents in a patient with vasospastic angina: Implications for pathogenesis.

A 64-year-old man was resuscitated from out-of-hospital VF, and coronary spasm was provoked by ergonovine at catheterization. An ECG was analyzed before and after each intracoronary injection of drugs or contrast medium. The baseline ECG showed nondiagnostic J waves in leads II, III, and aVF, but administration of acetylcholine, contrast medium and nitroglycerin into the right coronary artery induced a distinct augmentation of J-wave amplitudes with changes in the QRS morphology. Transient ischemia induced by the intracoronary administration of these agents seemed to be the mechanism underlying the increase in J-wave amplitudes.

Differences in coagulation responses to vascular injury between uninterrupted dabigatran and apixaban: A clinical prospective randomized study.

BACKGROUND: The coagulation response during vascular injury with uninterrupted administration of direct oral anticoagulants has not been elucidated. OBJECTIVE: Our aim was to evaluate differences in coagulation responses after vascular injury between uninterrupted direct thrombin inhibitor and direct factor Xa inhibitor recipients. METHODS: Patients scheduled for catheter ablation for atrial fibrillation were randomly assigned to receive dabigatran or apixaban in this prospective, randomized, comparative, parallel-group study. Venous blood was collected 3 times: 180 minutes after taking the anticoagulant on the day before the procedure, before vascular punctures of the ablation procedure, and 10-15 minutes after the start of vascular punctures. RESULTS: Forty-two patients were enrolled. The prothrombin fragment 1+2 level, the primary end point, was much larger after vascular puncture in the uninterrupted dabigatran recipients (median, 83 pmol/L; interquartile range, 56-133 pmol/L) than in the uninterrupted apixaban recipients (median, 1 pmol/L; interquartile range, -3 to 19 pmol/L; P < .001). Antithrombin levels decreased after vascular puncture in dabigatran recipients, and both protein C and antithrombin levels decreased after vascular puncture in apixaban recipients. CONCLUSION: Unlike uninterrupted apixaban, uninterrupted dabigatran does not inhibit thrombin generation in response to vascular injury.

Incidence and Implications of J waves Observed During Coronary Angiography.

J waves may be observed during coronary angiography (CAG), but they have not been fully studied. We investigated the characteristics of J waves in 100 consecutive patients during CAG. The patients and their family members had no history of cardiac arrest. Approximately 60% of patients had ischemic heart disease, previous myocardial infarction, or angina pectoris, but at the time of this study, the right coronary artery was shown to be normal or patent after stenting. Electrocardiogram was serially recorded to monitor J waves and alteration of the QRS complex during CAG. In 12 patients (12%), J waves (0.249 ± 0.074 mV) newly appeared during right CAG, and in another 13 patients (13%), preexisting J waves increased from 0.155 ± 0.060 mV to 0.233 ± 0.133 mV during CAG. Left CAG induced no J waves or augmentation of J waves. Distinct alterations were observed in the QRS complex during CAG of both coronary arteries. Mechanistically, myocardial ischemia induced by contrast medium was considered to result in a local conduction delay, and when it occurred in the inferior wall, the site of the late activation of the ventricle, the conduction delay was manifested as J waves. In conclusion, J waves were confirmed to emerge or increase during angiography of the right but not the left coronary artery. Myocardial ischemia induced by contrast medium caused a local conduction delay that was manifested as J waves in the inferior wall, the site of the late activation of the ventricle.

Clinical impact of ECG changes on oversensing of subcutaneous implantable cardioverter-defibrillators.

BACKGROUND: Inappropriate shocks delivered by subcutaneous implantable cardioverter-defibrillators (S-ICDs) are most frequently caused by cardiac oversensing. However, the predictors for oversensing of S-ICD remain unclear. OBJECTIVE: We aimed to investigate the predictors for oversensing of S-ICD, especially clinical impact of an electrocardiographic (ECG) change. METHODS: We retrospectively enrolled 99 consecutive patients who underwent S-ICD implantation between 2013 and 2021. Oversensing events were defined as inappropriate charge of the capacitors induced by cardiac or noncardiac signals other than tachycardia. RESULTS: During a median follow-up period of 34 months (interquartile range 20-50 months), 11 of 99 patients (11%) experienced 34 oversensing events and 4 patients (4%) received inappropriate shocks during their events. Six patients exhibited ECG changes (bundle branch block, 3; ventricular pacing, 1; inverted T wave, 1; poor R-wave progression, 1) during the follow-up period. Oversensing events were observed in 4 of 6 patients with ECG change (67%), and 3 patients underwent S-ICD removal because of inevitable shock. Contrastingly, of the remaining patients without ECG change, all 7 patients who experienced oversensing events could continue using S-ICD with the reprogramming sensing vector and/or restriction of excessive exercise. Logistic regression analysis showed that lower voltage of Sokolow-Lyon ECG (V1S + V5R) was the predictor of oversensing in patients without ECG change. When the cutoff value was 2.1 mV, the sensitivity, specificity, positive predictive value, and negative predictive value were 85.7%, 62.7%, 15.7%, and 98.1%, respectively. CONCLUSION: Unavoidable oversensing resulting in S-ICD removal is caused by ECG change. Oversensing in patients without ECG change can be managed.

Dynamic left ventricular outflow tract obstruction complicated with takotsubo cardiomyopathy: The acute phase of takotsubo cardiomyopathy manifests latent left ventricular outflow tract obstruction.

Dynamic left ventricular (LV) outflow tract (LVOT) obstruction is sometimes complicated with takotsubo cardiomyopathy (TC). The present case involves a 70-year-old woman with chest discomfort. Seven years earlier, transthoracic echocardiography revealed LVOT obstruction due to a sigmoid-shaped septum. She underwent urgent cardiac catheterization for suspected acute coronary syndrome. She was diagnosed as having TC with LVOT obstruction. After undergoing conservative treatment, her LV function normalized and the LVOT obstruction resolved. After the LV wall motion normalized, administering an intravenous infusion of dobutamine again provoked LVOT obstruction. In this situation, the presence of TC manifested latent LVOT obstruction. .