Serum Elabela Level Significantly Increased in Patients with Complete Heart Block

Objective

To investigate the change in serum Elabela level, a new apelinergic system peptide, in patients with complete atrioventricular (AV) block and healthy controls.

Methods

The study included 50 patients with planned cardiac pacemaker (PM) implantation due to complete AV block and 50 healthy controls with similar age and gender. Elabela level was measured in addition to routine anamnesis, physical examination, and laboratory tests. Patients were divided into two groups, with and without AV block, and then compared.

Results

In patients with AV block, serum Elabela level was significantly higher and heart rate and cardiac output were significantly lower than in healthy controls. Serum Elabela level was found to be positively correlated with high-sensitive C-reactive protein and N-terminal pro-brain natriuretic peptide (NT-proBNP) levels, but negatively correlated with heart rate, high-density lipoprotein cholesterol, and cardiac output. In linear regression analysis, it was found that these parameters were only closely related to heart rate and NT-proBNP. Serum Elabela level was determined in the patients with AV block independently; an Elabela level > 9.5 ng/ml determined the risk of complete AV-block with 90.2% sensitivity and 88.0% specificity.

Conclusion

In patients with complete AV block, the serum Elabela level increases significantly before the PM implantation procedure. According to the results of our study, it was concluded that serum Elabela level could be used in the early determination of patients with complete AV block.

A Comparative Study of Perventricular and Percutaneous Device Closure Treatments for Isolated Ventricular Septal Defect: A Chinese Single-Institution Experience

OBJECTIVES

To compare the advantages and disadvantages of perventricular and percutaneous procedures for treating isolated ventricular septal defect (VSD).

METHODS

A total of 572 patients with isolated VSD were selected in our hospital between January 2015 and December 2016. The patients' median age and weight were five years (1-26 years) and 29 kg (9-55 kg), respectively. The median diameter of VSD was 6.0 mm (5-10 mm). Patients were divided into two groups. In group A, perventricular device closure was performed in 427 patients; in group B, 145 patients underwent percutaneous device closure.

RESULTS

Four hundred twelve patients in group A and 135 patients in group B underwent successful closure. The total occlusion rate was 98.5% (immediately) and 99.5% (3-month follow-up) in group A, which were not significantly different from those in group B (97.7% and 100%, respectively). Patients in group A had longer intensive care unit (ICU) stay than those in group B, but patients in group B experienced significantly longer operative times than those in group A. The follow-up period ranged from 8 months to 1.5 year (median, 1 year). During the follow-up period, late-onset complete atrioventricular block occurred in two patients. No other serious complications were noted in the remaining patients.

CONCLUSION

Both procedures are safe and effective treatments for isolated VSD. The percutaneous procedure has obvious advantages of shorter ICU stay and less trauma than the perventricular procedure. However, the perventricular procedure is simpler to execute, results in a shorter operative time, and avoids X-ray exposure.

Cardioneuroablation in the Management of Vasovagal Syncope, Sinus Node Dysfunction and Functional Atrioventricular Block: Patient Selection Based on Supporting Evidence

The problem with the regulation of the autonomic nervous system or paroxysmal reflex vagal activation episodes may have an important role in the pathophysiology of vasovagal syncope (VVS), sinus bradycardia or periods of sinus arrest, and variable-degree atrioventricular block (AVB). Because existence of structural heart disease tends to shift the vagosympathetic balance towards a sympathetic predominance, vagally-mediated bradyarrhythmias (VMB) usually occurs in young individuals with structurally normal hearts. However, similar reflex problems may be observed in the elderly people and even those with structural heart disease. Modification of the efferent arm of autonomic nervous system by ablation of main ganglionated plexi (GPs) is called as cardioneuroablation (CNA) and seems as a promising treatment option for appropriately selected patients with VMB. This review outlines the process of patient selection for CNA on the basis of supporting evidence.

Cardiac resynchronization therapy for left ventricular dysfunction induced by chronic right ventricular pacing in a child

Cardiac resynchronization therapy (CRT) has been proven its value in adult patients with congestive heart failure of low ejection fraction and wide QRS duration. Contrast to adult patients, CRT has been rarely applied for young patients. We report on a 9-yr-old boy with progressive left ventricular (LV) dilatation and dysfunction following chronic VVI pacemaker therapy for congenital complete atrioventricular block associated with maternal anti-SSA/Ro and SSB/La antibody. His LV dysfunction was improved after epicardially established CRT.

Cardioneuroablation in the Management of Vasovagal Syncope, Sinus Node Dysfunction, and Functional Atrioventricular Block - Techniques

Cardioneuroablation is an emerging therapy to treat vasovagal syncope, functional atrioventricular block and sinus dysfunction. Currently, there are several effective approaches due to the complex modulation of autonomic nervous system. In this review, we describe techniques of this innovative therapy based on published literature and our experiences.

Usefulness Of Ivabradine To Treat "unexpected" Heart Failure Caused By "acute" Right Ventricular Pacing

We present the case of a patient with a heart failure episode induced by acute right ventricular pacing. After reversal of beta-blockers because of chronic obstructive pulmonary disease (COPD) exacerbation, the following sinus tachycardia caused a 2:1 atrioventricular block and consequent continuous right ventricular pacing. He was treated with the selective I(f) inhibitor ivabradine, that reduced both ventricular pacing percentage and heart rate without affecting atrioventricular conduction. Ivabradine may be a valuable option in treatment of patients with atrioventricular conduction disturbances.

Digoxin and Symptomatic Bradyarrhythmia: the 'demon' or a 'red herring'

Digoxin toxicity has been implicated in all forms of cardiac arrhythmias with the notable exception of Mobitz II atrioventricular block, which is very rare. The manifestation is quite variable, ranging from being asymptomatic to gastrointestinal, cardiac, and neurologic symptoms. The manifestations can be protean in the elderly, the most vulnerable group, where degenerative cardiac conduction system diseases add another layer of intrigue by providing an intrinsic substrate for cardiac dysrhythmia. This is in addition to age-related alteration of digoxin pharmacokinetics, use of multiple medications, chronic conditions, and electrolyte derangement, all of which increase the propensity for digoxin toxicity. We present a case of various atrioventricular conduction blocks in a septuagenarian following the use of digoxin.

Recurrent Syncope During Migraine Attacks

Migraine is a cyclic condition with attacks consisting mainly of intense headaches, sensory intolerance, and nausea or vomiting. Loss of consciousness during attacks is often attributed exclusively to a neurally mediated reflex to pain, although it may also be due to migraine's autonomic impairment, with cardiac conduction abnormalities, probably in relation to a degree of reduced sympathetic function. We report the case of a 51-year-old woman presenting episodes of syncope exclusively after vomiting during migraine attacks. A 24-hour Holter monitoring performed during a migraine attack disclosed an intermittent complete atrioventricular block coincident with an episode of syncope. The patient was implanted with a pacemaker without further syncopes on subsequent attacks. This case highlights the importance of clinical suspicion and investigation of syncope during migraine attacks. Recurrent syncope during migraine should not be attributed to pain to avoid misdiagnosis and ensure the treatment of other important causes of syncope.

Role of genetic testing in young patients with idiopathic atrioventricular conduction disease

AIMS

To investigate the role of genetic testing in patients with idiopathic atrioventricular conduction disease requiring pacemaker (PM) implantation before the age of 50 years.

METHODS AND RESULTS

All consecutive PM implantations in Southern Switzerland between 2010 and 2019 were evaluated. Inclusion criteria were: (i) age at the time of PM implantation: < 50 years; (ii) atrioventricular block (AVB) of unknown aetiology. Study population was investigated by ajmaline challenge and echocardiographic assessment over time. Genetic testing was performed using next-generation sequencing panel, containing 174 genes associated to inherited cardiac diseases, and Sanger sequencing confirmation of suspected variants with clinical implication. Of 2510 patients who underwent PM implantation, 15 (0.6%) were young adults (median age: 44 years, male predominance) presenting with advanced AVB of unknown origin. The average incidence of idiopathic AVB computed over the 2010-2019 time window was 0.7 per 100 000 persons per year (95% CI 0.4-1.2). Most of patients (67%) presented with specific genetic findings (pathogenic variant) or variants of uncertain significance (VUS). A pathogenic variant of PKP2 gene was found in one patient (6.7%) with no overt structural cardiac abnormalities. A VUS of TRPM4, MYBPC3, SCN5A, KCNE1, LMNA, GJA5 genes was found in other nine cases (60%). Of these, three unrelated patients (20%) presented the same heterozygous missense variant c.2531G > A p.(Gly844Asp) in TRPM4 gene. Diagnostic re-assessment over time led to a diagnosis of Brugada syndrome and long-QT syndrome in two patients (13%). No cardiac events occurred during a median follow-up of 72 months.

CONCLUSION

Idiopathic AVB in adults younger than 50 years is a very rare condition with an incidence of 0.7 per 100 000 persons/year. Systematic investigations, including genetic testing and ajmaline challenge, can lead to the achievement of a specific diagnosis in up to 20% of patients. Heterozygous missense variant c.2531G > A p.(Gly844Asp) in TRPM4 gene was found in an additional 20% of unrelated patients, suggesting possible association of the variant with the disease.

Trapped p waves causing loss of physiological left bundle branch pacing

OBJECTIVE

We present the case of a 75-year-old woman with severe aortic stenosis and moderate left ventricular dysfunction, who underwent elective transcatheter aortic valve replacement. After the procedure, the patient developed a left bundle branch block and a long PR interval. For this reason, a dual chamber pacemaker with pacing in the left bundle branch area was implanted. On device interrogation, we confirmed the presence of functional atrial undersensing causing loss of ventricular electric resynchronization. This case highlights the importance of recognizing this problem and, by means of device reprogramming and pharmacological intervention, suggests a stepwise approach to solve it.

Initial Experience with Left Bundle Branch Area Pacing in Patients with Atrioventricular Block and Impaired LV Function

Chronic right ventricular (RV) pacing can exacerbate heart failure in patients with a low left ventricular ejection fraction (LVEF). Left bundle branch area pacing (LBBAP) has emerged as a novel physiological pacing technique; however, information remains limited on its use among patients with a low EF. This study investigated the safety and short-term clinical outcomes of LBBAP among patients with impaired left ventricular (LV) function. This retrospective analysis of pacemakers at Chosun University Hospital, South Korea, included all patients with impaired LV function (EF<50%) who underwent pacemaker implantation for atrioventricular blockage from 2019-2022. Clinical characteristics, 12-lead electrocardiography findings, echocardiography findings, and laboratory parameters were evaluated. Composite outcomes were defined as all-cause mortality, cardiac death, and hospitalization due to heart failure during the 6-month follow-up. Altogether 57 patients (25 men; mean age, 77.4±10.8 y; LVEF, 41.5±3.8%) were divided into LBBAP (n=16), biventricular pacing (BVP; n=16), and conventional RV pacing (RVP; n=25) groups. In the LBBAP group, the mean paced QRS duration (pQRSd) was narrower (119.5±14.7 vs. 140.2±14.3 vs. 163.2±13.9; p<0.001) and cardiac troponin I level was elevated post-pacing (1.14±1.29 vs. 0.20±0.29 vs. 0.24±0.51, p=0.001). Lead parameters were stable. One patient was hospitalized, and four died (one patient each from heart failure admission, myocardial infarction, unexplained death, and pneumonia in RVP vs. one from intracerebral hemorrhage in BVP) during the follow-up period. In conclusion, LBBAP is feasible in patients with impaired LV function without acute or significant complications and provides a remarkably narrower pQRSd with a stable pacing threshold.

Atrioventricular block as the initial presentation of calcified bicuspid aortic valve

BACKGROUND

Bicuspid aortic valve (BAV) is one of the most common and important congenital heart disorders in adults. If a patient with congenital disorders is not diagnosed early, the patient's disease may progress to a severe condition and thus diagnosis of the main disorder will be rendered difficult.

CASE REPORT

A 34 year-old male patient referred to a referral medical care unit for cardiac electrophysiological study with cardiac shock due to complete heart block 3 months ago and he underwent Dual-Chamber permanent pacemaker (PPM) implantation. Thick and calcified bicuspid AV with invasion to interventricular septum, moderate to severe valve insufficiency (AI), severe aortic valve stenosis (AS), and dilated ascending aorta were observed at his echocardiography. Aortic valve replacement (AVR), aneurysm of ascending aorta, root replacement with tube graft (Bentall Procedure), and also a 3 chambers intracardiac defibrillator (ICD) were used. After 2 weeks of operation, he was discharged and at the first post-hospitalization visit (1 week later), his cardiovascular condition was acceptable.

CONCLUSION

Thick calcified aortic root is a less studied and potential contributing risk factor for AV block after AVR. Therefore, in candidates of aortic valve replacement, considering conductive disorders, especially in patients with calcified valve, is mandatory. Irreversible AV block requiring PPM implantation is a rare condition following AVR.