Rapid Arrhythmias Research Articles

Ablation of tachyarrhythmias with zero fluoroscopy technique in patients under 18 years of age. 4-year follow-up

Abstract Introduction Arrhythmias occur in 5% of preschool patients, with an increased incidence in adolescence. Treatment of rapid arrhythmias or tachyarrhythmias may include ablation of the cardiac structures. Catheter ablation is the possibility of producing an injury to the endocardium by administering energy through the catheter in a limited and controlled way to those parts of the cardiac tissue where tachycardias are initiated and/or maintained, it is performed through a catheter connected to an energy source, which is introduced through arterial or venous lines. to the chambers of the heart. In recent years, different technological innovations have emerged aimed at better understanding and identifying the substrate of arrhythmia, thus facilitating catheter navigation and reducing the need for fluoroscopy. Different studies have shown that ablation without fluoroscopy is feasible, especially in the context of supraventricular tachycardia. Objective To describe the clinical characteristics of pediatric patients undergoing ablation with zero fluoroscopy in a pediatric hospital of the National Medical Center of the West (CMNO). Material and Methods descriptive and retrospective study, the clinical characteristics of 42 patients who were taken to arrhythmia ablation by zero fluoroscopy technique at the CMNO IMSS pediatric hospital for 4 years in the period from June 2019 to May 2023 were analyzed. Results A total of 42 patients, of which 55% were male, with a median age of 13 years with a range of 4 to 17 years, the median weight was 49 kg with a standard deviation of +- 19.5 kg. Of the arrhythmias treated, supraventricular tachycardia accounted for 97.6% of cases and ventricular arrhythmias for 2.4%. Of the supraventricular tachycardias, atrioventricular reentrant tachycardia accounted for 68.35%. 25 cases with a diagnosis of Wolff Parkinson White with 28% of the right lateral location, followed by the right postoseptal 24%. Structural heart disease was present in 31% of the cases, the most frequent being Ebstein's anomaly (41.7%). Immediate success rate was 97.3%, with recurrence in the first three months of follow-up of 5.4%. A Kaplan-Meier curve was performed, showing a success rate of 77.3% at 12 months of follow-up. No statistical significance was found in patients with congenital heart disease and recurrence, p=0.698 and with Fisher's exact test, p=0.530. Conclusion Ablation of cardiac arrhythmias in children under 18 years of age without the use of fluoroscopy is an effective procedure, obtaining an immediate success rate of 97.3% of patients, 77.3% of patients are free of recurrence one year after treatment. There was no statistical significance for patients with congenital heart disease who might have recurrence.

Mechanism of Guigan Longmu Decoction in the Treatment of Arrhythmias Based on Network Pharmacology and Untargeted Metabolomics Assays.

Guigan longmu decoction (GGLM), a traditional Chinese medicine compound, has demonstrated efficacy in treating rapid arrhythmia clinically. Nevertheless, its mechanism of action remains elusive. This study aims to elucidate the molecular mechanism underlying the efficacy of GGLM in treating arrhythmia utilizing non-targeted metabolomics, widely-targeted metabolomics, and network pharmacology, subsequently validated through animal experiments. Initially, network pharmacology analysis and widely-targeted metabolomics were performed on GGLM. Subsequent to that, rats were administered GGLM intervention, and nontargeted metabolomics assays were utilized to identify metabolites in rat plasma postadministration. The primary signaling pathways, core targets, and key active ingredients of GGLM influencing arrhythmia were identified. Additionally, to validate the therapeutic efficacy of GGLM on arrhythmia rat models, a rat model of rapid arrhythmia was induced via subcutaneous injection of isoproterenol, and alterations in pertinent pathogenic pathways and proteins in the rat model were assessed through qRT-PCR and Western blot following GGLM administration. The results of network pharmacology showed that 99 active ingredients in GGLM acted on 249 targets and 201 signaling pathways, which may be key to treating arrhythmia. Widelytargeted metabolic quantification analysis detected a total of 448 active ingredients in GGLM, while non-targeted metabolomics identified 279 different metabolites and 10 major metabolic pathways in rats. A comprehensive analysis of the above results revealed that the core key active ingredients of GGLM in treating arrhythmia include calycosin, licochalcone B, glabridin, naringenin, medicarpin, formononetin, quercetin, isoliquiritigenin, and resveratrol. These active ingredients mainly act on the relevant molecules and proteins upstream and downstream of the MAPK pathway to delay the onset of arrhythmia. Animal experimental results showed that the heart rate of rats in the model group increased significantly, and the mRNA and protein expression of p38, MAPK, JNK, ERK, NF-kb, IL-1β, and IL-12 in myocardial tissue also increased significantly. However, after intervention with GGLM, the heart rate of rats in the drug group decreased significantly, while the mRNA and protein expression of p38 MAPK, JNK, ERK1, NF-kb, IL-1β, and IL-12 in myocardial tissue decreased significantly. GGLM, as an adjunctive therapy in traditional Chinese medicine, exhibits favorable therapeutic efficacy against arrhythmia. This can be attributed to the abundant presence of bioactive compounds in the formulation, including verminin, glycyrrhizin B, glabridine, naringenin, ononin, quercetin, isorhamnetin, and kaempferol. The metabolites derived from these active ingredients have the potential to mitigate myocardial inflammation and decelerate heart rate by modulating the expression of proteins associated with the MAPK signaling pathway in vivo.

Severe heart failure with rapid arrhythmia: Treatment with amiodarone and esmolol and its effect on TGF-β1, APN and PIIINP

Rapid arrhythmia (RA) is a major complication of severe heart failure (SHF). Treatment with anti-arrhythmic drug amiodarone though improves the myocardial blood supply and suppress arrhthmia, its clinical application is unsatisfactory. Amiodarone combined with another class II antiarrhythmic drug, esmolol shows rapid onset and good efficacy. Here, we studied the effects of amiodarone and esmolol in severe heart failure (SHF) with rapid arrhythmia (RA) and its effect on TGF-β1, APN and PIIINP. A total of 180 SHF patients with RA treated at Zhejiang Provincial Hospital of Traditional Chinese Medicine were selected and divided into experimental group (n = 90) and control group (n = 90) according to the random number table method. The control group was given routine therapy + amiodarone therapy, and the experimental group was given routine therapy + amiodarone + esmolol therapy. Cardiac function measures including cardiac index (CI), mean arterial pressure (MAP) and ejection fraction (LVEF), diastolic blood pressure (DBP), systolic blood pressure (SBP) and heart rate (HR), serum TGF-β1, APN and PIIINP levels were observed in both groups before and 48 h after treatment. After treatment, the CI, MAP and LVEF of the experimental group were greater than those of the control group (P<0.05); DBP, SBP and HR were greater (or higher) in the experimental group than in the control group (P<0.05); serum TGF-β1 and PIIINP levels in experimental groups were all lower than in control group and serum APN levels were higher (P<0.05) than in control group. The total effective rate of the experimental group was less than that of the control group (P<0.05). There was no difference in the incidence of adverse effects between the two groups (P>0.05). The results indicate that treatment of severe heart failure (SHF) with rapid arrhythmia (RA) by amiodarone and esmolol may safely enhance cardiac function, blood pressure and heart rate, improve efficacy, inhibit the progression of myocardial fibrosis, and improve serum TGF-β1, APN and PIIINP levels.

Deep Learning-Based Electrocardiograph in Evaluating Radiofrequency Ablation for Rapid Arrhythmia.

This study is aimed at analyzing the important role of deep learning-based electrocardiograph (ECG) in the efficacy evaluation of radiofrequency ablation in the treatment of tachyarrhythmia. In this study, 158 patients with rapid arrhythmia treated by radiofrequency ablation were divided into effective treatment group (142 cases) and ineffective treatment group (16 cases). ECG examination was performed on all patients, and the indicators of ECG examination were quantified by the deep learning-based convolutional neural network model. The indicators of ECG examination of the effective treatment group and the ineffective treatment group were compared. The results showed that compared with the ineffective treatment group, the end-systolic volume (ESV), end-diastolic volume (EDV), end-systolic volume index (ESVI), and end-diastolic volume index (EDVI) of the effective treatment group were significantly decreased, and the left ventricular ejection fraction (LVEF) was significantly increased (P < 0.05). After radiofrequency ablation, the ventricular rate of patients in the effective treatment group was significantly lower than that of the ineffective treatment group at 12 h and 24 h after treatment (P < 0.05). In addition, compared with patients in the ineffective treatment group, the QT dispersion of the ECG in the effective treatment group was significantly higher (P < 0.05). The accuracy, specificity, and sensitivity of ECG in evaluating the therapeutic effect of patients with tachyarrhythmia were 86.81%, 84.29%, and 77.27%, respectively. The area under the curve was determined as 0.798 according to the receiver operating characteristic (ROC) curve of the subjects. In summary, indicators of ECG examination based on deep learning can provide auxiliary reference information for the efficacy evaluation of radiofrequency ablation in the treatment of tachyarrhythmia.

671 First-in-man mapping and ablation of ventricular tachycardia using a novel ablation catheter with microelectrodes and thermocouples

Abstract Aims Catheter ablation (CA) is an important therapeutic option for patients with recurrent ventricular tachycardia (VT). Recently, a novel contact-force sensing catheter (QDOT, Biosense Webster) allowing radiofrequency ablation in a temperature-controlled fashion, equipped with microelectrodes and thermocouples has been developed and tested in very-high power short duration CA of atrial fibrillation. As of today, this catheter has never been used for VT ablation. To describe the safety and short-term clinical performance of the novel QDOT catheter for the ablation of recurrent VT/electrical storm. Methods and results Case 1: a 43-year-old male patient with prior anterior myocardial infarction (MI), left ventricular (LV) dysfunction with an apical aneurysm, and recurrent VT episodes was admitted to our hospital for CA of VT. The patient underwent high-density electroanatomical mapping of the left ventricle using a multipolar catheter (PentaRay, Biosense Webster), which showed an extensive apical dense scar region, corresponding to the ventricular aneurysm. When the QDOT catheter was advanced in that region, late/fragmented potentials were detected by microelectrodes as well as by conventional electrodes. During the procedure, a sustained VT with right bundle branch block (RBBB)-inferior axis morphology and transition in V2 could be induced. We recorder diastolic fragmented potentials inside the aneurysm, where the novel catheter previously showed late/fragmented potentials; radiofrequency energy delivery with conventional settings (40 W) in that area led to rapid arrhythmia termination (Figure A). At the end of the procedure, VTs were no more inducible. Case 2: a 79-year-old male patient with prior inferior MI, mild LV dysfunction with a 5 cm × 5 cm × 3 cm aneurysm of the basal-mid inferior wall, and two previous CAs for recurrent VT presented to our hospital for electrical storm due to multiple episodes of slow VT (cycle, 470 ms, RBBB morphology, inferior axis, transition in V6), which were refractory to antiarrhythmic drug treatment. We decided to perform redo CA using the QDOT catheter, which revealed long and fragmented low-amplitude diastolic potentials inside the LV aneurysm (Figure B). VT was rapidly terminated by means of radiofrequency energy delivery with usual settings (40 W) in this region, and was no more inducible afterwards. Conclusions The novel ablation catheter showed favourable manoeuverability in the ventricle, while also allowing a precise characterization of the tachycardia circuitry and of the arrhythmogenic myocardial substrate, which was enhanced by the availability of microelectrodes. We believe that this preliminary experience may pave the way for further assessments of this new technology in the so far unexplored ventricular milieu.

Taquicardias supraventriculares

Supraventricular arrhythmias are a set of tachycardias or rapid arrhythmias in which any of the structures located above the bundle of His is essential for its onset and maintenance. By definition, they are rapid rhythms, with a heart rate above 100 bpm. They have a good prognosis, although on occasion they can have an incessant nature and favor the development of tachycardiomyopathy. The term supraventricular tachycardia (SVT) refers to a group of supraventricular arrhythmias which excludes atrial fibrillation, as it is an entirely different entity.

Interest of ivabradine in pediatric arrhythmia. About a case and review of the literature

By inhibiting the pacemaker current if of the sinoatrial node (SN), ivabradine was first use as an alternative to betablockers in the treatment of heart failure [1] . For a few years, it has been proposed as an adjuvant therapy for postoperative [2] or congenital junctional ectopic tachycardia [3] . But ivabradine can also be effective on atrial and ventricular abnormal automaticity [4] . We report the case of a 9 years old girl who was diagnosed of polymorphic atrial tachycardia at birth. The child was first treated by amiodarone. When amiodarone had to be withdraw because of thyroid dysfunction, multiple antiarrhythmic drugs were tested alone or in association: betablockers, flecainide, digoxine. Despite medication, the child experimented multiple high rate non-sustained tachycardia per day. After an antiarrhythmic washout, ivabradine was started. Fig. 1 is the patient Holter without any treatment showing a very anarchic rhythm, mostly rapid arrhythmia. Fig. 2 is the patient Holter after only 2 takes of ivabradine that shows a marked efficacy of the drug. Ivabradine inhibits selectively the If current that is responsible of the pacemaker activity of the SN and the AV node. If current can also be responsible of abnormal automaticity of the atrial and ventricular myocardium. In such case, ivabradine is highly effective to control the arrhythmia. Still, ivabradine efficacy is difficult to predict, but regarding its overall safety, it can be tested. In a randomized, double-blind trial of pediatric patient with dilated cardiomyopathy, Bonnet et al. did not report more adverse event with ivabradine than with placebo [5] . The outcome of atrial ectopic arrhythmia in the pediatric population is good: 78% will resolve spontaneously when diagnosed under 3 years old [6] . Ivabradine could be an alternative to catheter ablation in the very young or in pediatric patient with multifocal arrhythmia or organized arrhythmia close to the AV conduction system.

Atrial flutter with 1:1 rapid wide QRS atrioventricular conduction in a patient following traditional surgical repair on atrial septal defect: a case study

: One-to-one atrioventricular conduction (AVC) during atrial flutter (AFL) is one of the most life-threatening arrhythmias and hemodynamically perilous. We present the diagnostic and analytical strategy for a patient who developed a paroxysm of AFL with 1:1 AVC. We did Brugada’s stepwise approach and the ventricular tachycardia (VT) score for the diagnosis. Meanwhile, we did RS/QRS ratio in lead V6. Through observations of the dynamic changes during and after amiodarone treatment, we made the diagnosis. Firstly, we calculated the VT score, and the result showed score 1. Secondly, we made Brugada’s stepwise approach to exclude VT. Meanwhile, we did RS/QRS ratio in lead V6, and the result showed the rate of 0.369 (<0.41, cut off 0.41). The result also suggested that the wide QRS AV tachycardia was not VT. Finally, amiodarone was administered under the guidance of a cardiovascular physician. Through observations of the dynamic changes during and after amiodarone treatment, the electrocardiogram (ECG) showed AFL with 2:1 AVC. The AFL rate was the same as the rate of rapid arrhythmia attack. Retrospectively, the rapid arrhythmia ECG was diagnosed as AFL with 1:1 rapid wide QRS AVC. AFL with 1:1 AVC is an uncommon but challenging arrhythmia. Brugada’s stepwise approach and the VT score can assist clinical physicians in making the diagnosis. In our study, we also verify that the RS/QRS ratio in lead V6 is beneficial to differentiate supraventricular tachycardia (SVT) with a right bundle branch block (RBBB) pattern from VT. Through observation of the changes of ECG before and after amiodarone, we can make the diagnosis. One should be conscious of the different presentations of AFL with 1:1 wide QRS AVC to avoid misdiagnosis and mismanagement.

Abstract 15886: When the Giant is Hidden but Not Dormant

Background: Giant cell myocarditis is a rare etiology of cardiogenic shock, which requires high index of suspicion, rapid immunosuppressive therapy, and sometimes mechanical circulatory supportCase presentation69 year old woman with prior medical history of non-ischemic dilated cardiomyopathy and recovered left ventricular ejection fraction (LVEF) presented with cardiogenic shock complicated by acute renal and liver injury requiring support with Impella 5.5. Suspicion for myocarditis was high and patient underwent endomyocardial biopsy and started on high dose steroids. Biopsy was negative for myocarditis. Despite support, patient had progressive shock and incessant ventricular arrhythmia necessitating IV antiarrhytmics and escalation to VA ECMO in addition to Impella and eventually to central Centrimag BiVAD with drainage cannulas in right atrium and LV apex, and reinfusion catheters in pulmonary artery and ascending aorta. (Figure 1) She was urgently listed for heart transplantation as a status 1 and one day later underwent successful orthotopic heart transplantation. Pathological examination of the explanted heart was consistent with Giant cell Myocarditis (Figure 2) Conclusion: Giant cell myocarditis is a rare etiology of cardiogenic shock. Suggestive features include rapid hemodynamic deterioration and incessant ventricular arrhythmia. Negative initial endomyocardial biopsy is not enough to rule out the disease in high clinical suspicion. Rapid escalation of support is warranted in fulminant cases to preserve end organ function and improve survival.(Figure 1 Created with BioRender.com)

Electrocardiogram stream level correlated patterns as features to classify heartbeats for arrhythmia prediction

PurposeDigital computing and machine learning-driven predictive analysis in the diagnosis of non-communicable diseases are gaining significance. Globally many research studies are focusing on developing comprehensive models for such detection. Categorically in the proposed diagnosis for arrhythmia, which is a critical diagnosis to prevent cardiac-related deaths, any constructive models can be a value proposition. In this study, the focus is on developing a holistic system that predicts the scope of arrhythmia from the given electrocardiogram report. The proposed method is using the sequential patterns of the electrocardiogram elements as features.Design/methodology/approachConsidering the decision accuracy of the contemporary classification methods, which is not adequate to use in clinical practices, this manuscript coined a new dimension of features to perform supervised learning and classification using the AdaBoost classifier. The proposed method has titled “Electrocardiogram stream level correlated patterns as features (ESCPFs),” which takes electrocardiograms (ECGs) signal streams as input records to perform supervised learning-based classification to detect the arrhythmia scope in given ECG record.FindingsFrom the results and comparative reports generated for the study, it is evident that the model is performing with higher accuracy compared to some of the earlier models. However, focusing on the emerging solutions and technologies, if the accuracy factors for the model can be improved, it can lead to compelling predictions and accurate outcome from the process.Originality/valueThe authors represent complete automatic and rapid arrhythmia as classifier, which could be applied online and examine long ECG records sequence efficiently. By releasing the needs for extraction of features, the authors project an application based on raw signals, one result to heart rates date, whose objective is to lessen computation time when attaining minimum classification error outcomes.

Successful case of complex atrial flutter occurring in a patient with congenitally corrected transposition of the great arteries, aberrant left atrial appendage, and situs inversus

BackgroundCongenitally corrected transposition of great arteries (ccTGA) is a rare congenital cardiac defect with atrioventricular and ventriculoarterial discordance which leads to heart failure and limits patients’ lifespan. The extremely aberrant cardiac structure makes electrophysiological procedure and radiofrequency ablation very difficult to be performed in such patients. Until now, there were only sporadical cases that have reported the successful ablation of atrial flutter in ccTGA patients.Case presentationWe report a case of a 36-year-old male who was diagnosed with dextrocardia, atrial septal defect and congenitally corrected transposition of great arteries (ccTGA) at a young age and received atrial septal defect repair and morphological tricuspid valve plasty in 2014. As for reasons of heart failure and atrial flutter, he frequently suffered from progressively worsening dyspnea and recurrent episodes of palpitations. Cardiac anatomic imaging reconstruction before electrophysiological test revealed an unusually huge left atrial appendage in this patient. After high-density mapping of both right atrium and left atrium, activation mapping showed reentry circuit loops were located in left atrium. Successful ablation strategy was performed under the guidance of high-density mapping and entrainment.ConclusionThis is a clinical case showing high-density mapping and successful ablation of a complex dual-loop atrial flutter in a patient with ccTGA and aberrant left atrial appendage. The successful procedure corroborates clinical utility of high-density mapping approach in the treatment of the patients with complex congenital heart disease accompanied by rapid arrhythmia, can be simpler, safer and more effective.

Arrhythmia mechanisms and spontaneous calcium release: Bi-directional coupling between re-entrant and focal excitation.

Spontaneous sub-cellular calcium release events (SCRE) are conjectured to promote rapid arrhythmias associated with conditions such as heart failure and atrial fibrillation: they can underlie the emergence of spontaneous action potentials in single cells which can lead to arrhythmogenic triggers in tissue. The multi-scale mechanisms of the development of SCRE into arrhythmia triggers, and their dynamic interaction with the tissue substrate, remain elusive; rigorous and simultaneous study of dynamics from the nanometre to the centimetre scale is a major challenge. The aim of this study was to develop a computational approach to overcome this challenge and study potential bi-directional coupling between sub-cellular and tissue-scale arrhythmia phenomena. A framework comprising a hierarchy of computational models was developed, which includes detailed single-cell models describing spatio-temporal calcium dynamics in 3D, efficient non-spatial cell models, and both idealised and realistic tissue models. A phenomenological approach was implemented to reproduce SCRE morphology and variability in the efficient cell models, comprising the definition of analytical Spontaneous Release Functions (SRF) whose parameters may be randomly sampled from appropriate distributions in order to match either the 3D cell models or experimental data. Pro-arrhythmogenic pacing protocols were applied to initiate re-entry and promote calcium overload, leading to the emergence of SCRE. The SRF accurately reproduced the dynamics of SCRE and its dependence on environment variables under multiple different conditions. Sustained re-entrant excitation promoted calcium overload, and led to the emergence of focal excitations after termination. A purely functional mechanism of re-entry and focal activity localisation was demonstrated, related to the unexcited spiral wave core. In conclusion, a novel approach has been developed to dynamically model SCRE at the tissue scale, which facilitates novel, detailed multi-scale mechanistic analysis. It was revealed that complex re-entrant excitation patterns and SCRE may be bi-directionally coupled, promoting novel mechanisms of arrhythmia perpetuation.

Clinical characteristics, medication selection and outcome of rapid atrial arrhythmia in children without organic heart disease

目的 探讨无器质性心脏病儿童快速型房性心律失常临床特征、用药选择及转归，以提高临床医生对本病的诊治水平。 方法 对我院近年来收治的20例无器质性心脏病快速型房性心律失常的临床资料进行回顾性分析和总结。 结果 20例患儿中，男13例，女7例。有8例在胎儿期就发现有心率增快伴不齐。患儿年龄≤3个月者多无明显症状，仅有2例患儿出现心源性休克征象；3～10岁患儿7例中有2例曾出现呕吐、面色苍白、出汗、乏力或胸闷、心悸等症状。常规心电图及24 h动态心电图显示阵发性房性心动过速7例、慢性房性心动过速5例、紊乱性房性心动过速2例、非阵发性房性心动过速2例、频发房性期前收缩伴反复短阵房性心动过速10例、单纯心房扑动2例、3例可见混有心房颤动。20例患儿经心脏超声、X线胸片、心肌酶谱、肌钙蛋白等检测均未发现有器质性心脏病征象。20例患儿均采用地高辛、普萘洛尔联合治疗方案，多在治疗1周后控制快速心率、甚至转为窦性心律。学龄前儿童对抗心律失常药物敏感性较差，疗程相对较长。2例患儿并发快速心律失常性心肌病。 结论 快速型房性心律失常多发生在小婴儿，其次为幼儿和学龄前儿童，学龄患儿相对少见。多数无明显症状，少数可发生心力衰竭和心源性休克。常规心电图和24 h动态心电图检查可确定快速型房性心律失常的具体类型。采用地高辛和普萘洛尔联合治疗控制心率和转律效果较好。本病常呈自限性，预后多数良好。

Selective autonomic stimulation of the AV node fat pad to control rapid post-operative atrial arrhythmias.

Junctional ectopic tachycardia (JET) and atrial fibrillation (AF) occur in patients recovering from open-heart surgery (OHS). Pharmacologic treatment is used for the control of post-operative atrial arrhythmias (POAA), but is associated with side effects. There is a need for a reversible, modulated solution to rate control. We propose a non-pharmacologic technique that can modulate AV nodal conduction in a selective fashion. Ten mongrel dogs underwent OHS. Stimulation of the anterior right (AR) and inferior right (IR) fat pad (FP) was done using a 7-pole electrode. The IR was more effective in slowing the ventricular rate (VR) to AF (52 +/- 20 vs. 15 +/- 10%, p = 0.003) and JET (12 +/- 7 vs. 0 +/- 0%, p = 0.02). Selective site stimulation within a FP region could augment the effect of stimulation during AF (57 +/- 20% (maximum effect) vs. 0 +/- 0% (minimum effect), p<0.001). FP stimulation at increasing stimulation voltage (SV) demonstrated a voltage-dependent effect (8 +/- 14% (low V) vs. 63 +/- 17 (high V) %, p<0.001). In summary, AV node fat pad stimulation had a selective effect on the AV node by decreasing AV nodal conduction, with little effect on atrial activity.

Clinical analysis of 19 cases of pregnant women with rapid arrhythmia in the treatment of radiofrequency catheter ablation

paroxysmal palpitation, chest tightness, dizziness, and blurred vision. Arrhythmia types: 1 case of atrial flutter and atrial tachycardia, 1 case of atrial flutter and atrial fibrillation, 1 case of atrial fibrillation, 3 cases of supraventricular tachycardia, 1 case of atrial tachycardia and supraventricular tachycardia, 4 cases of ventricular tachycardia, 3 cases of ventricular premature beats and ventricular tachycardia, and 5 cases of atrial tachycardia. All cases were treated by drugs, but all failed 2 cases of them were performed esophageal pacing and cardioversion and also failed.(2)Treatment plan: 19 cases after treatment of arrhythmia, completely terminated, the first 7 patients(from 2002 to 2014)were operated in a small amount of radiation under the guidance, the other 12 patients(after 2015)were carried out in the Ensite NavX mapping system, whichwere operated with zero radiation. Complications and adverse reactions: 1 case of uterine contraction end operation and was gived magnesium sulfate 3 days intravenous inhibition of uterine contractions, 1 case occurred vagal reflex caused by reduced blood pressure and was gived fluid infusion utill normal blood pressure.(3)Maternal and neonatal outcomes: in addition 1 case of pregnancy to give up, the remaining 18 cases were full-term pregnant women, including 4 cases of vaginal delivery and 14 cases of cesarean section. The survival neonates were followed up for 1 to 14 years, average(2.0 ± 2.9)years. The infants were well developed during the follow-up period. Conclution: Radiofrequency catheter ablation is a safe and effective method for the treatment of pregnancy complicated with rapid arrhythmia.

Pheochromocytoma with Ventricular Tachycardia as the Presenting Symptom

To the Editor: Although the triad of palpitations, headaches, and sweating is generally recognized as the classic presentation for pheochromocytoma, we reported the case of a patient with pheochromocytoma who first presented with ventricular tachycardia (VT). This case shows the importance of a broad differential diagnosis when the clinical presentation is unusual. A 17-year-old woman presented with episodic palpitation and headaches during physical activities for 4 years. The symptoms resolved after 3–5 min of rest. Two days before admission, she was admitted to the emergency department with persistent palpitations and headaches, and the blood pressure (BP) was 180/90 mmHg. The admission echocardiography (ECG) revealed a sinus rate of 92 beats/min. There was no family or personal history of syncope, cardiac arrest, and sudden death. The physical examination was unremarkable. The admission and peak creatine kinase-MB was 153 U/L and 157 U/L, respectively. During follow-up, the patient presented with recurrent palpitation and headaches when sitting or standing. During these episodes the BP was 160–200/90–100 mmHg and the pulse rate was elevated at 148 beats/min. Cardiac monitoring showed VT with a heart rate (HR) of 150 beats/min [Figure 1a]. Three episodes of VT were recorded during persistent hypertension. The symptoms were relieved after maintaining a recumbent position for 1–2 min. The 24 h urinary catecholamines and urinary vanillylmandelic acid levels were elevated. Abdominal ultrasound revealed a right adrenal mass with a diameter of 6 cm which was confirmed on abdominal computed tomography [Figure 1b]. A pheochromocytoma was diagnosed. Figure 1 (a) Echocardiography showing ventricular tachycardia. (b) Contrast-enhanced computed tomography scan of the upper abdomen revealing a tumor of the right adrenal gland. The patient was hemodynamically stabilized in the supine position with the administration of phentolamine (a nonspecific α-adrenergic blocker) and metoprolol (a selective β-antagonist). A right adrenalectomy was performed, yielding a 6.0 cm nodule confirmed to be a pheochromocytoma by histology. The hypertension was controlled and no arrhythmias were documented during 12 months of follow-up. Pheochromocytoma is a catecholamine-producing tumor that originates from the adrenal medulla or extra-adrenal chromaffin cells. The main clinical manifestation of pheochromocytoma is paroxysmal or persistent hypertension, accompanied by arrhythmias, such as sinus tachycardia, paroxysmal supra VT, atrial fibrillation, or ventricular premature contractions. We have reported a rare case of pheochromocytoma with VT as the presenting symptom. Frequent episodes of VT are almost always preceded by vital sign fluctuation (elevated HR and BP). Paulin et al.[1] reported that the sudden release of catecholamine from the pheochromocytoma is associated with the mechanism underlying VT. Excessively elevated catecholamine levels could lead to abnormal myocardial electrical activity, such as over opening of ion channels, enhanced ion exchange pump function, thus causing extremely large amounts of sodium, potassium, and calcium ion flow through the membranes, resulting in intensive myocardial autorhythmicity, conductivity, and triggered activities. Furthermore, increased catecholamine levels can reduce the cardiac ventricular fibrillation threshold, predispose to ventricular fibrillation, lead to sudden death,[2] and contribute to abnormal repolarization, thus causing all types of rapid arrhythmia. Ceremuzynski et al.[3] have shown that plasma catecholamine concentrations are increased in dogs during acute myocardial ischemia and a relationship between the blood catecholamine concentration and the severity of ventricular arrhythmias. Cardiac abnormalities caused by pheochromocytoma includes myocarditis, acute myocardial infarction, transient left ventricular systolic dysfunction, and cardiomyopathy. Bravo et al.[4] reported that catecholamines cause myocardial necrosis, focal myofibrillar degeneration, and subsequent fibrous scar formation. Left ventricular systolic dysfunction may resemble stress-induced cardiomyopathy, also known as takotsubo cardiomyopathy and is reversible in patients with pheochromocytoma.[5] Moreover, long-term high catecholamine levels can lead to myocardial hypertrophy and heart failure. The presence of sustained VT can be treated with radio-frequency ablation but such treatment would not abolish the systemic arrhythmogenic mechanism and would not resolve the symptoms or prevented the potential onset of other tachyarrhythmias. This case illustrates the importance of a complete differential diagnosis when the clinical presentation is unusual. In a hypertensive patient with a typical presentation consisting of palpitations and headache, and an ECG demonstrates VT or other tachyarrhythmias, a pheochromocytoma should be included in the differential diagnosis. In addition, biochemical testing and imaging studies will guide the diagnosis and allow complete resolution of symptoms following resection of the pheochromocytoma. The preoperative use of phentolamine, a nonspecific α-adrenergic blocker has a theoretical pharmacologic basis. The β-blocker propranolol is used when tachycardia or catecholamine-induced arrhythmias are present and should only be started after α-blocker has been established to avoid life-threatening hypertension. In conclusion, this case shows that VT is an unusual and initial cardiovascular presenting symptom in patients with a pheochromocytoma. Pheochromocytoma must be considered in patients with frequent VT plus sudden changes in BP. Resection of chromaffin cell tumor will completely relieve the symptoms. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.

GW26-e1322 Incidence and influence factors of new onset rapid atrial arrhythmias patients with permanent pacemakers

GW26-e1322 Incidence and influence factors of new onset rapid atrial arrhythmias patients with permanent pacemakers

Heart beats: not to be beaten.

Heart beats: not to be beaten.

A New Algorithm to Diagnose Atrial Ectopic Origin from Multi Lead ECG Systems - Insights from 3D Virtual Human Atria and Torso

Rapid atrial arrhythmias such as atrial fibrillation (AF) predispose to ventricular arrhythmias, sudden cardiac death and stroke. Identifying the origin of atrial ectopic activity from the electrocardiogram (ECG) can help to diagnose the early onset of AF in a cost-effective manner. The complex and rapid atrial electrical activity during AF makes it difficult to obtain detailed information on atrial activation using the standard 12-lead ECG alone. Compared to conventional 12-lead ECG, more detailed ECG lead configurations may provide further information about spatio-temporal dynamics of the body surface potential (BSP) during atrial excitation. We apply a recently developed 3D human atrial model to simulate electrical activity during normal sinus rhythm and ectopic pacing. The atrial model is placed into a newly developed torso model which considers the presence of the lungs, liver and spinal cord. A boundary element method is used to compute the BSP resulting from atrial excitation. Elements of the torso mesh corresponding to the locations of the placement of the electrodes in the standard 12-lead and a more detailed 64-lead ECG configuration were selected. The ectopic focal activity was simulated at various origins across all the different regions of the atria. Simulated BSP maps during normal atrial excitation (i.e. sinoatrial node excitation) were compared to those observed experimentally (obtained from the 64-lead ECG system), showing a strong agreement between the evolution in time of the simulated and experimental data in the P-wave morphology of the ECG and dipole evolution. An algorithm to obtain the location of the stimulus from a 64-lead ECG system was developed. The algorithm presented had a success rate of 93%, meaning that it correctly identified the origin of atrial focus in 75/80 simulations, and involved a general approach relevant to any multi-lead ECG system. This represents a significant improvement over previously developed algorithms.

Sternal cleft: Anaesthetic management of a rare congenital anomaly.

Sir, A sternal cleft is a rare congenital anomaly resulting from the failure of fusion of lateral sternal bars during the 3rd month of intrauterine development.[1] It may be complete or incomplete (bifid type), depending on the degree of fusion of two lateral sternal bars, the latter being more common.[2,3] Associated anomalies, particularly cardiac anomalies, result in poor outcomes.[4,5] The surgical procedure is associated with critical changes in haemodynamics and cardiopulmonary mechanics, necessitating invasive monitoring, preparedness for cardiopulmonary bypass and resuscitation (CPR).[6] Here, we report anaesthetic management of a case of sternal cleft repair with a brief review of available literature. A full-term male baby, weighing 2.6 kg, was delivered by caesarean section. The attending paediatrician noted a longitudinal depression at the sternal region which was more evident during inspiration [Figure 1]. Pulsation of great vessels was easily seen through the defect which was covered by a thin layer of skin. Two parallel and completely separated sternal bars were palpated along the depression. There was no anterior abdominal wall defect, diastasis of recti, fascial haemangioma, atrophic skin or paradoxical movement of the thoracic cage. A provisional diagnosis of isolated sternal cleft was made, and the baby was evaluated for associated anomalies. Chest X-ray revealed normal lung fields with a wide gap between the medial ends of the clavicles [Figure 2]. Echocardiogram and blood investigations were normal. The child was posted for sternal cleft repair on the 3rd postpartum day. In the operating room, standard monitoring was attached. The pulse rate was 130/min, oxygen saturation 97% with oxygen (O2) supplementation by nasal cannula at 3L/min and respiratory rate was 34/min. The child was induced with inhalation of sevoflurane (2 to 8%) in O2 and two peripheral intravenous lines were secured. The injections of fentanyl (5μg) and atracurium (1.5mg) were administered, and trachea was intubated with 3.5mm uncuffed endotracheal tube. The right radial artery was cannulated for invasive blood pressure monitoring. Anaesthesia was maintained with isoflurane in O2 /air (40–60) mixture. The child was put on pressure controlled ventilation, and adequate tidal volume (VT) was achieved with peak inspiratory pressures (PIP) of 18 mmHg. A vertical midline incision from the suprasternal notch to xiphoid process was given by the surgeons, and margins of sternal bars were freshened, followed by closure of the defect. The blood loss was minimal. PIP and haemodynamics were observed for next 10 min before knotting the sutures. PIP of 20 mmHg was required to achieve the same VT with no significant changes in haemodynamics. On the 2nd postoperative day, the trachea was extubated, and the child was discharged home in stable condition on the 7th day. Figure 1 Obvious midline depression in the child Figure 2 Wide gap between the medial ends of the clavicles The reported incidence of sternal cleft varies across the institutes. Acastello et al.[7] noted an incidence of 0.15% of all chest deformities during a 25 years period observation. It is usually diagnosed at birth due to the presence of cosmetic deformity and is generally asymptomatic. Associated cardiac anomalies, defects in the anterior chest wall (ectopia cordis), or the presence of Cantrell's Pentalogy (defects involving the abdominal wall, sternum, diaphragm, pericardium and heart) indicate poor prognosis.[4,5] Surgical correction is required to restore bony protection to the vital organs and great blood vessels, to provide normal intra-thoracic pressure-volume relationships and to eliminate paradoxical movement of the thoracic viscera.[1,2,3] Surgery is preferred in the new born period as the thoracic cage is more compliant, and the closure of the chest wall can easily accommodate the thoracic viscera without compressing the underlying structures.[6] It presents distinct challenges to the anaesthesiologist due to the potential involvement of multiple organ systems and the risk of direct injury to the vital organs. Associated complex congenital heart disease or poor baseline cardiac functions warrant standby cardiopulmonary bypass.[4,5,6] Arterial and central venous pressure monitoring is useful, as is trans-oesophageal echocardiography (TEE). Intraoperative TEE offers real-time information on volume status and cardiac output. The repair may lead to compression on the intra-thoracic organs which may cause haemodynamic instability and decreased lung compliance necessitating invasive monitoring, and close observation of ventilatory parameters. Rapid blood loss, arrhythmias, cardiac dysfunction and pneumothorax are the possible complications.[2,3] Literature advises test closure for 5–10 min while observing the haemodynamics and cardiopulmonary interactions.[3] To conclude, repair of sternal cleft requires invasive haemodynamic monitoring, close observation of ventilatory parameters and preparedness for CPR. Elective postoperative mechanical ventilation with adequate analgesia helps in early recovery.