Possibility of steroid therapy without pacemaker implantation in patients with sarcoidosis presenting atrioventricular block.

Atrioventricular Block (AVB) is one of the common manifestations in cardiac sarcoidosis (CS). Although pacemaker implantation is generally recommended in patients with CS complicated by symptomatic AVB, some case reports have shown that they can be managed by steroid therapy without pacemaker implantation. The aim of this study was to evaluate the feasibility and effectiveness of steroid therapy without pacemaker implantation in patients with CS complicated by symptomatic AVB. We performed medical record review of consecutive ten CS patients who admitted Nippon Medical School Hospital for symptomatic second or third degree AVB between April 2015 and March 2021. Of the studied population, steroid therapy before pacemaker implantation was feasible in three patients with second degree AVB. Two of them showed subsequent recovery of atrioventricular conduction to 1:1, and they were managed by steroid therapy without pacemaker. The remaining one patient showed no improvement of atrioventricular conduction and required pacemaker implantation. Seven patients with third degree AVB required device implantation (pacemaker; n = 7, cardiac resynchronization therapy defibrillator; n = 1) before steroid therapy mainly because of hemodynamic instability. Steroid therapy without pacemaker implantation might be feasible, and possibly be effective in patients with CS presenting second degree AVB. However, the feasibility is limited in patients with third degree AVB.

Localization of Late Gadolinium Enhancement and Its Association with Ventricular Tachycardia in Patients with Cardiac Sarcoidosis.

Sustained ventricular tachycardia (sVT), leading to sudden cardiac death, is one of the common manifestations in cardiac sarcoidosis (CS). Although late gadolinium enhancement (LGE) on cardiac magnetic resonance (CMR) has been reported to be associated with sVT, the relationships of its localization to sVT have not been fully evaluated.To evaluate the localization of LGE and its relationships to sVT in patients with CS, we reviewed medical record of consecutive 31 patients with CS who underwent CMR. The localization of LGE was divided into four categories: Left ventricular (LV) septum, LV free wall, right ventricular (RV) septum, and RV free wall. We investigated the association of sVT with localization of LGE and other parameters including serum biomarkers LV ejection fraction on echocardiography and Fluorine-18-fluorodeoxyglucose (FDG) accumulation on positron emission tomography (PET) -CT.Of the studied population, 8 patients (25.8%) were known to present with sVT among 31 CS patients. LGE was observed in the RV free wall in 6 patients with sVT, whereas it was in 5 patients without sVT (75.0% versus 21.7%, P = 0.022). Univariate analysis showed that only LGE in the RV free wall was associated with sVT (odds ratio [OR]: 10.80; 95% confidence interval [CI]: 1.64-70.93, P = 0.013).LGE in the RV free wall was associated with sVT in patients with CS.

Prognostic impact of newly detected atrial fibrillation in patients with hypertrophic cardiomyopathy following cardiac implantable electronic device implantation.

Atrial fibrillation (AF) is the most common arrhythmia in patients with hypertrophic cardiomyopathy (HCM). The present study aimed to investigate the incidence and prognostic impact of newly detected AF after cardiac implantable electronic device (CIED) implantation with HCM patients. Fifty-six patients (33 men, age 57 ± 17 years) with HCM who underwent CIED implantations with no previous history of AF at the time of implantation (ICD n = 46, Pacemaker n = 10) were retrospectively enrolled. During 5.7 ± 3.6 years of follow-up, AF was newly detected in 20 (36%) of 56 patients after the CIED implantation (AF group) and the rest of the patients had no newly detected AF (non-AF group). The presence of mitral regurgitation (HR 8.49; 95% CI 2.29-30.6 P < 0.01) and concomitant NYHA II-IV (HR 3.37; 95% CI 1.30-8.86 P = 0.01) were the independent predictors of newly detected AF. During the follow-up, all patients in the AF group started anticoagulation mean 21 days after detection of AF, and none had a stroke during the follow-up period. The rate of appropriate ICD therapy (log-rank P = 0.95), inappropriate ICD therapy (log-rank P = 0.78), and all-cause death (log-rank P = 0.23) were similar between the two groups. However, the incidence of hospitalizations due to heart failure was higher in the AF group (55% vs. 6% log-rank P < 0.01). In conclusion, the incidence of newly detected AF after CIED implantations in HCM patients was high. The newly detected AF was associated with worsening heart failure and careful follow-up is recommended.

Differential diagnosis between LQT1 and LQT2 by QT/RR relationships using 24-hour Holter monitoring: A multicenter cross-sectional study.

BACKGROUND: The clinical course and therapeutic strategies in the congenital long QT syndrome (LQTS) are genotype-specific. However, accurate estimation of LQTS genotype is often difficult from the standard 12-lead ECG. OBJECTIVES: This study aims to evaluate the utility of QT/RR slope analysis by the 24-hour Holter monitoring for differential diagnosis of LQTS genotype between LQT1 and LQT2. METHODS: This cross-sectional study enrolled 54 genetically identified LQTS patients (29 LQT1 and 25 LQT2) recruited from three medical institutions. The QT-apex (QTa) interval and the QT-end (QTe) interval at each 15-second were plotted against the RR intervals, and the linear regression (QTa/RR and QTe/RR slopes, respectively) was calculated from the entire 24-hour and separately during the day or night-time periods of the Holter recordings. RESULTS: The QTe/RR and QTa/RR slopes at the entire 24-hour were significantly steeper in LQT2 compared to those in LQT1 patients (0.262 ± 0.063 vs. 0.204 ± 0.055, p = .0007; 0.233 ± 0.052 vs. 0.181 ± 0.040, p = .0002, respectively). The QTe interval was significantly longer, and QTe/RR and QTa/RR slopes at daytime were significantly steeper in LQT2 than in LQT1 patients. The receiver operating curve analysis revealed that the QTa/RR slope of 0.211 at the entire 24-hour Holter was the best cutoff value for differential diagnosis between LQT1 and LQT2 (sensitivity: 80.0%, specificity: 75.0%, and area under curve: 0.804 [95%CI = 0.68-0.93]). CONCLUSION: The continuous 24-hour QT/RR analysis using the Holter monitoring may be useful to predict the genotype of congenital LQTS, particularly for LQT1 and LQT2.

Detection of arrhythmogenic substrate within QRS complex in patients with cardiac sarcoidosis using wavelet-transformed ECG.

Signal-averaged electrocardiography (SAECG) has been known to be useful for prediction of lethal ventricular arrhythmias (VA). However, this technique has limitations in patients with intraventricular conduction disturbance (IVCD), which is common in cardiac sarcoidosis (CS). Meanwhile, wavelet-transformed ECG (WTECG) has been reported to be useful for detecting arrhythmogenic substrate hidden within QRS complex. The objective of this study was to assess the utility of WTECG for detecting arrhythmogenic substrate in patients with CS. Forty-four CS patients including 18 patients with VA were retrospectively investigated. The parameters on the signal-averaged electrocardiography (SAECG) and the power of frequency components on WTECG were compared between VA group and non-VA group. Eighteen patients have VA (VT: n = 17, VF: n = 1). LP were detected in 17 in VA group and 24 in non-VA group. WTECG showed that high-frequency components (HFC; 80-150 Hz) were developed in VA group. Peak power value at 150 Hz (P150) was significantly higher in VA group than that in non-VA group (442.9 ± 160.2 vs 316.7 ± 100.8, p = 0.006). The receiver operating characteristic (ROC) curve analysis showed an optimal cutoff point of 336 of P150 for detecting patients with VA, with 82.4% sensitivity, 61.5% specificity, and area under the curve of 0.74 (95% confidence interval [CI] 0.59-0.89). WTECG may be useful for detecting CS patients who are prone to VA.

Validation of wearable textile electrodes for ECG monitoring.

A highly conductive textile was woven from nano-fibers coated with the PEDOT-PSS polymer. The aim of this study was to assess the usefulness of textile electrodes for ECG recording as a smart garment. Electrode textile pads and lead wires were sewn to the lining of sportswear and their tolerability to repeated washings were tested up to 150 times. The electrical conductivity of the textile electrode remained functional for up to 50 machine washes. To assess the level of motion artifacts or noise during the daily monitoring of ECG, a single lead ECG with conventional or textile electrodes was recorded during supine rest, seated rest, upright trunk rotation (i.e., twisting), and stepping movement in 66 healthy adults. A Holter system was used for data storage and analysis. ECG patterns of P, QRS, and T waves were comparable between the conventional and textile electrodes. However, the signal-to-artifact-and/or-noise ratio (SAR) during twisting was larger in the textile electrodes than in the conventional electrodes. No skin irritation was seen in the textile electrodes. The single lead textile electrodes embedded in an inner garment were usable for continuous and/or repeated ECG monitoring in daily life except during vigorous trunk movement.

In-Hospital Electrical Storm in Acute Myocardial Infarction　- Clinical Background and Mechanism of the Electrical Instability.

BACKGROUND: Recurrent ventricular tachycardia (VT) and fibrillation (VF), the so-called "electrical storm" (ES) occurs at various stages of acute myocardial infarction (AMI), but its incidence, background, and short-term prognosis remain unclear. Methods and Results: A retrospective observational study was performed using the registry database of the Tokyo CCU Network. The individual data of 6,003 patients with AMI during 2011-2012 was corrected. ES was defined as more than 3 episodes of sustained VT/VF during a 24-h period as first documented after hospitalization. ES occurred in 55 patients after admission (0.9%). The ES(+) group had more severe heart failure (Killip class >III), more extensive MI (peak-CK), greater inflammatory reaction (CRP), history of diabetes, and more frequent application of hemodialysis as compared with the ES(-) group (n=5,865). When the ES patients were divided into Early-ES (n=37: ES occurred ≤48 h after the onset of MI) and Late-ES (n=15 >48 h after onset of MI) groups, logistic regression analysis revealed that Early-ES was associated with severity of MI, whereas Late-ES was related to systemic disorders, including inflammation, renal dysfunction, or diabetes. Late-ES was an independent predictor of in-hospital death. CONCLUSIONS: In-hospital ES was a rare clinical manifestation of AMI. The features and background of the ES varied as time elapsed after admission for MI.

Clinical and Electrocardiographic Characteristics of Electrical Storms Due to Monomorphic Ventricular Tachycardia Refractory to Intravenous Amiodarone.

BACKGROUND: Few reports are available on the characteristics of electrical storms of ventricular tachycardia (VT storm) refractory to intravenous (IV) amiodarone. METHODS AND RESULTS: IV-amiodarone was administered to 60 patients with ventricular tachyarrhythmia between 2007 and 2012. VT storms, defined as 3 or more episodes of VT within 24 h, occurred in 30 patients (68±12 years, 7 female), with 12 having ischemic and 18 non-ischemic heart disease. We compared the clinical and electrocardiographic characteristics of the patients with VT storms suppressed by IV-amiodarone (Effective group) to those of patients not affected by the treatment (Refractory group). IV-amiodarone could not control recurrence of VT in 9 patients (30%). The Refractory group comprised 5 patients with acute myocardial infarctions. Although there was no difference in the VT cycle length, the QRS duration of both the VT and premature ventricular contractions (PVCs) followed by VT was narrower in the Refractory group than in the Effective group (140±30 vs. 178±25 ms, P<0.01; 121±14 vs. 179±22 ms, P<0.01). In the Refractory group, additional administration of IV-mexiletine and/or Purkinje potential-guided catheter ablation was effective. CONCLUSIONS: IV-amiodarone-refractory VT exhibited a relatively narrow QRS tachycardia. The narrow triggering PVCs, suggesting a Purkinje fiber origin, may be treated by additional IV-mexiletine and endocardial catheter ablation.

Urgent catheter ablation for sustained ventricular tachyarrhythmias in patients with acute heart failure decompensation.

AIMS: Ventricular tachycardia (VT) and ventricular fibrillation (VF) are not uncommon in patients hospitalized with acute heart failure (AHF). We sought to evaluate the efficacy of urgent radiofrequency catheter ablation (RFCA) for recurrent VT/VF during AHF decompensations. METHODS AND RESULTS: The present study retrospectively analysed the data of 15 consecutive patients (69 ± 9 years, ischaemic heart disease in 10), who underwent urgent RFCA for frequent drug-refractory VT/VF episodes during an AHF decompensation with pulmonary congestion. The target arrhythmias were clinically documented monomorphic VTs in 10 patients, frequent premature ventricular contractions (PVCs) triggering VF in 4, and both in 1. The mean left ventricular ejection fraction was 26 ± 8%. The maximum number of arrhythmia episodes over 24 h was 9.1 ± 11.7. All RFCA sessions were completed without any major complications except for a temporary deterioration of pulmonary congestion in three patients (20%). Elimination and non-inducibility of the target arrhythmias were achieved in 13 patients (87%). Successful ablation site electrograms showed Purkinje potentials for all 5 PVCs triggering VF and 4 of 14 clinically documented monomorphic VTs (29%). Five patients (33%) underwent second sessions 10 ± 4 days after the first session for acute recurrences. Sustained VT/VF was completely suppressed during admission in 12 patients (80%), and the AHF ameliorated in 13 patients (93%). Twelve patients (80%) were discharged alive. CONCLUSION: Urgent RFCA for drug-resistant sustained ventricular tachyarrhythmias during AHF decompensations would be an appropriate therapeutic option. Purkinje fibres can be ablation targets not only in those with PVCs triggering VF, but also in those with monomorphic VT.

Electrophysiological and Histopathological Characteristics of Ventricular Tachycardia Associated With Primary Cardiac Tumors.

BACKGROUND: Ventricular tachycardia (VT) associated with primary cardiac tumors (PCTs) originating from the ventricles is rare, but lethal, in young patients. OBJECTIVES: This study aimed to clarify the mechanisms underlying primary cardiac tumor-related ventricular tachycardia (PCT-VT) and establish a therapeutic strategy for this form of VT. METHODS: Among 67 patients who underwent surgery for VT at our institute between 1981 and 2020, 4 patients aged 1 to 34 years, including 3 males, showed PCT-VT (fibroma, 2; lipoma, 1; and hamartoma, 1), which was investigated using a combination of intraoperative electroanatomical mapping and histopathological studies. RESULTS: All 4 patients developed electrical storms of sustained VTs refractory to multiple drugs and repetitive endocardial ablations. The VT mechanism was re-entry, and intraoperative electroanatomical mapping showed a centrifugal activation pattern originating from the border between the tumor and healthy myocardium, where fractionated potentials were detected during sinus rhythm. Histopathological studies of serial sections of specimens acquired from these areas revealed tumor infiltration into the surrounding myocardium with cell disorganization, exhibiting myocardial disarray. Several myocardia entrapped in the tumor edges contributed to the development and sustainment of re-entrant VT activation. In the 2 patients in whom complete resection was unfeasible, encircling cryoablation to entirely isolate the unresectable tumor was effective in suppressing VT occurrence. CONCLUSIONS: The mechanism underlying PCT-VT involves re-entry localized at the tumor edges. Myocardial disarray associated with tumor infiltration is a substrate for this form of VT. Cryoablation along the border between the tumor and myocardium is a promising therapeutic option for unresectable PCT-VT.

TAD boundary deletion causes PITX2-related cardiac electrical and structural defects.

While 3D chromatin organization in topologically associating domains (TADs) and loops mediating regulatory element-promoter interactions is crucial for tissue-specific gene regulation, the extent of their involvement in human Mendelian disease is largely unknown. Here, we identify 7 families presenting a new cardiac entity associated with a heterozygous deletion of 2 CTCF binding sites on 4q25, inducing TAD fusion and chromatin conformation remodeling. The CTCF binding sites are located in a gene desert at 1 Mb from the Paired-like homeodomain transcription factor 2 gene (PITX2). By introducing the ortholog of the human deletion in the mouse genome, we recapitulate the patient phenotype and characterize an opposite dysregulation of PITX2 expression in the sinoatrial node (ectopic activation) and ventricle (reduction), respectively. Chromatin conformation assay performed in human induced pluripotent stem cell-derived cardiomyocytes harboring the minimal deletion identified in family#1 reveals a conformation remodeling and fusion of TADs. We conclude that TAD remodeling mediated by deletion of CTCF binding sites causes a new autosomal dominant Mendelian cardiac disorder.

Surgery for ventricular tachycardia originating from the left ventricular summit.

OBJECTIVES: Ventricular tachycardia (VT) originating from the left ventricular summit region, the most superior region of the left ventricle surrounded by the major coronary arteries and veins, is frequently refractory to pharmacological therapies and endocardial and epicardial catheter ablation. METHODS: Eleven patients with an age from 31 to 79 (median 56) years old, underwent map-guided surgery for left ventricular summit VT. All patients had undergone 1-5 unsuccessful sessions of catheter ablation for incessant VT, preoperatively. Five patients had suffered VT storm and 1 had a history of cardiopulmonary resuscitation. Four patients had implanted with a defibrillator. Epicardium to endocardium transmural cryothermia was applied at the VT origin determined by intraoperative epicardial mapping with electro-anatomical mapping system. Harmonic scalpel was used to remove the epicardial fat and cryothermia was applied directly to the myocardium, avoiding thermal or mechanical injuries to the coronary vessels. Additional endocardial cryothermia at the VT origin was performed by a cryoprobe introduced into the left ventricular cavity through an aortotomy. RESULTS: There was no surgical mortality or long-term mortality related to VT during a median follow-up period of 60 months (interquartile range: 34-82). Five-year freedom from preoperatively documented left ventricular summit VT and non-documented VT was 91% and 73%, respectively. All the patients with postoperative VT underwent successful catheter ablation. Other patients were free from VT during the follow-up period. CONCLUSIONS: Epicardial to endocardial transmural cryothermia at the VT origin guided by intraoperative electro-anatomical mapping with a close collaboration with electrophysiologists was crucial in successful surgery for left ventricular summit VT.

Enlarged right atrium predicts pacemaker implantation after atrial fibrillation ablation in patients with tachycardia-bradycardia syndrome.

Introduction: Although catheter ablation (CA) of tachycardia-bradycardia syndrome (TBS) in patients with atrial fibrillation (AF) is considered to be an effective treatment strategy, pacemaker implantations (PMIs) are often required even after a successful CA. This study aimed to elucidate the clinical predictors of a PMI after CA. Methods: From 2011 to 2020, 103 consecutive patients diagnosed with TBS were retrospectively enrolled in the study. Among the 103 patients, 54 underwent a PMI and 49 CA of AF. During 47.4 ± 35.4 months after 1.4 ± 0.6 CA sessions, 37 (75.5%) of 49 patients were free from atrial arrhythmia recurrences. PMIs were performed in 11 patients (PMI group) and the remaining 38 did not receive a PMI (non-PMI group). Results: When comparing the PMI and non-PMI groups, there were no differences in the basic mean heart rate (P = 0.36), maximum pauses detected by 24-hour Holter-monitoring (P = 0.61), and other clinical parameters between the two groups while the right atrial area index was larger (42.1 ± 24.0 vs. 21.8 ± 8.4 cm2/m2 P = 0.002) in the PMI group than non-PMI group. The ROC curve analysis showed that the optimal cutoff point of the ratio of the right atrial area index to the left atrial area index for predicting a PMI following CA was 0.812 (Sensitivity 72.7%, specificity 71.1%, positive predictive value 42.1%, negative predictive value 90.0%, diagnostic accuracy 71.4%, AUC = 0.81). Conclusion: Right atrial enlargement prior to CA was considered to be one of the risk factors for a PMI after CA of AF.

Long-Term Electrocardiographic Follow-Up of a Patient with Light-Chain Cardiac Amyloidosis.

Amyloid light-chain (AL) cardiac amyloidosis can cause restrictive cardiomyopathy, which has a poor prognosis. Although electrocardiography (ECG) is useful for its diagnosis and management, there are few reports on the long-term follow-up of electrocardiographic changes in affected patients. The present patient was a 62-year-old woman who visited our hospital for assessment of palpitations and lower leg edema. A chest radiograph showed cardiac enlargement, and ECG revealed sinus rhythm, first-degree atrioventricular block, low QRS voltage in the limb leads and a pseudo-myocardial infarction pattern in the precordial leads. Echocardiography revealed left ventricular hypertrophy with systolic and diastolic dysfunction. Immunoelectrophoresis demonstrated M-protein (IgGλ), and bone marrow biopsy suggested IgGλ-type plasmacytoma. Myocardial biopsy findings were compatible with cardiac amyloidosis. On the basis of these findings, we diagnosed AL cardiac amyloidosis. Melphalan-prednisolone (MP) therapy was started in conjunction with treatment for non-sustained ventricular tachycardia and congestive heart failure. Two years and 4 months later, the sinus rhythm converted to atrial tachycardia. At a follow-up examination at 4 years and 8 months, right branch block appeared. After that, intraventricular conduction worsened, and the low voltage in the limb leads was not observed. Seven years after diagnosis, she was hospitalized for treatment of pneumonia and heart failure with tachycardia. On the seventh day of hospitalization, heart rhythm changed to atrial stand-still with escaped ventricular rhythm and she died of cardiac arrest. These ECG changes are valuable information regarding the pathophysiological changes that occur in AL cardiac amyloidosis.

Protective Effect of Catheter Ablation of Atrial Fibrillation on the Renal Function in Patients With Hypertrophic Cardiomyopathy.

Atrial fibrillation (AF) is a common arrhythmia in patients with hypertrophic cardiomyopathy (HCM) and is associated with renal function deterioration. The protective effects of catheter ablation (CA) of AF on renal function in patients with HCM remain unsolved. From 2009 to 2020, a total of 169 consecutive patients with HCM and AF (age 70 ± 12, 87 males) were retrospectively evaluated. The estimated glomerular filtration rate (eGFR) was evaluated at the study enrollment or 1 month before the CA and reevaluated 3 and 12 months later. In the 169 patients, 63 underwent CA of AF (ablation group), and the remaining 106 did not (control group). After propensity score matching, 45 pairs were matched. The baseline eGFR was similar between the 2 groups (p = 0.83). During a mean follow-up period of 34 ± 27 months, sinus rhythm was maintained in 36 patients (80%) after 1.7 ± 0.8 ablation procedures. The eGFR significantly decreased from baseline to 3 months (p <0.01) and from baseline to 1 year (p <0.01) in the control group, whereas the eGFR in the ablation group was maintained both from baseline to 3 months (p = 0.94) and from baseline to 1 year (p = 1.00) after the CA. The change in the eGFR between baseline and 12 months was significantly smaller in the ablation group than in the control group (p <0.01). After logistic regression analysis, CA of AF was the independent predictor of an improvement of eGFR (odds ratio 2.81, 95% confidence interval 1.08 to 7.36, p = 0.04). In conclusion, CA of AF had a protective effect on renal function in patients with HCM.

Perioperative coronary artery spasms in patients undergoing catheter ablation of atrial fibrillation.

PURPOSE: Catheter ablation (CA) is an established treatment for atrial fibrillation (AF). Although coronary artery spasms (CAS) during or after ablation procedures have been described as a rare complication in some case reports, the incidence and characteristics of this complication have not been fully elucidated. The present observational study aimed to clarify the CAS in a large number of patients experiencing AF ablation. METHODS: A total of 2913 consecutive patients (male: 78%, mean 66 ± 10 years) who underwent catheter ablation of AF were enrolled. RESULTS: Nine patients (0.31%, mean 66 ± 10 years, 7 males) had transient ST-T elevation (STE). Eight out of the 9 patients had STE in the inferior leads. STE occurred after the transseptal puncture in 7 patients, after the sheath was pulled out of the left atrium in 1, and 2 h after the ablation procedure in 1. Six patients had definite angiographic CAS without any sign of an air embolization on the emergent coronary angiography. In the3 other patients, the STE improved either directly after an infusion of nitroglycerin or spontaneously before the CAG. The patients with CAS had a higher frequency of a smoking habit (89% vs. 53%; P = .04), smaller left atrial diameter (36 ± 6 vs. 40 ± 7; P = .07), and lower CHADS2 score (0.6 ± 0.5 vs. 1.3 ± 1.1; P = .004) than those without. CONCLUSIONS: Although the incidence was rare (0.31%), CAS should be kept in mind as a potentially life-threatening complication throughout an AF ablation procedure especially performed under conscious sedation.