Atrioventricular Heart Block Research Articles

Minimally invasive transthoracic closure of ventricular septal defects without cardiopulmonary bypass under guidance of transepicardial echocardiography

Objective To introduce a new technique: minimally invasive transthoracic closure of ventricular septal defects (VSD) without cardiopulmonary bypass (CPB) under guidance of transepicardial echocardiography (TECE). Methods A total of 41 patients with VSD, 5 months to 6 years, averaging (15.1±18.5)months, underwent transthoracic device closure. The weight of these patients ranged from 5 to 26.0 kg with an average weight of (10.78 ± 6.87) kg. The diameter of their VSD ranged from 3 to 8.5 mm with an average of (5.2 ± 1.13) mm. After small median sternotomy incision, an appropriately sized VSD occluder was inserted into the left ventricle via VSD, then the occluder was released and the VSD was closed. TECE was used to monitor the whole procedure to guide the device positioning and evaluate the cursive effect instantly after operation. Results The procedure was successful in 38 patients. Three cases failed, including two cases whose guiding wire could not pass through VSD and one case whose occluder could not fix well. Three patients had tiny residual shunt after operation, two vanished during the follow-up period, and one case still had small amount residual shunt because of the occluders shifting. In 6 to 36 months follow-up, neither complete atrioventricular heart block nor aortic insufficiency was found in any patient. Conclusions The transthoracic closure of ventricular septal defects without cardiopulmonary bypass under guidance of transepicardial echocardiography is easy, safe, and efficient. Key words: Heart septal defects, ventricular/SU; Heart catheterization; Echocardiography/MT; Surgical procedures, minimally invasive/MT; Cardiac surgical procedures

Analysis of pregnancy, labor and neonatal course in babies with prenatally-diagnosed complete atrioventricular heart block

Complete heart block (third-degree atrioventricular block) is a defect of the conduction system of the heart, in which the impulse generated in the sinoatrial node does not propagate to the ventricles, and thus the latter contract independently of the atria. A third-degree atrioventricular block can be either congenital or acquired. In 60-70% of the cases, the congenital heart block results from destruction of the conduction system of the fetal heart by anti-Ro/SSA and anti-La/SSB antibodies present in maternal serum. The antibodies are synthesized in the course of autoimmune maternal conditions, most often systemic lupus erythematosus or rarer rheumatoid arthritis, dermatomyositis or Sjögren's syndrome. The complete block can occur as an isolated defect or be associated with structural anomalies of the fetal heart. A total of five patients whose fetuses were diagnosed with the third-degree atrioventricular block have been hospitalized at the Department of Obstetrics, Medical University of Gdansk between 2012 and 2014. We present the data of the five patients, hospitalized at the Department of Obstetrics, Medical University of Gdansk, whose fetuses were diagnosed prenatally with the complete heart block. The cases differ in terms of etiology clinical outcome, and postnatal treatment. All data are presented in Table I. We emphasize the role of appropriate pregnancy management and careful monitoring of the fetal condition. From obstetrical perspective, it is important to monitor the condition of fetuses with the third-degree atrioventricular block ultrasonographically and echocardiographically; in turn, cardiotocography is less useful in this setting. Therefore, a non-reactive cardiotocographic tracing should not constitute an indication for a preterm delivery. An affected fetus should be delivered in a tertiary center for perinatal care that cooperates with a pediatric cardiology center. An efficient program for cardologic prenatal care and close cooperation between obstetricians, neonatologists, pediatric cardiologists, and cardiac surgeons constitute the key to a successful outcome.

Successful Implantation of Bipolar Epicardial Leads and Dual Chamber Pacemaker in Infant After Postoperative Atrioventricular Heart Block

Total atrioventricular (AV) block is inconvenient and serious complication of open heart surgery. Permanent total AV block requires the implantation of permanent pacemaker in order to allow normal hemodynamics and patient’s survival. In infancy additional challenge is the surgical approach, the selection of electrodes and PM, as well as place of implantation. We are publishing case report of successful double-chamber DDD pacemaker implantation at an infant born with Fallot tetralogy and with low birth weight due to complete AV block after primary surgical correction of these congenital defects.

Putting Heart Block Back in the “Lyme Light”

We report a case of syncope in a young patient who presented with high-degree, variable atrioventricular heart block. Despite having no other classic manifestations of Lyme disease, she was treated with intravenous ceftriaxone for Lyme carditis on high clinical suspicion due to geographic location. The heart block resolved within 24h of treatment. Although rare, we demonstrate the importance of considering Lyme carditis in patients who present with new-onset heart block and a history of living in an endemic area. Initiation of empiric antibiotic therapy can lead to rapid resolution of this condition.<Learning objective: Although uncommon, Lyme carditis may present without any other classic signs or symptoms of Lyme disease. It should be considered in any patient who presents with new-onset atrioventricular heart block and a history of living in an endemic area. Prompt initiation of empiric antibiotic therapy can be both diagnostic and therapeutic.>

Sarcoidosis and heart disease: Diagnosis and management

Sarcoidosis remains one of the most enigmatic diseases; often present without symptoms and yet potentially able to affect any organ system with serious consequences. Heart involvement portends probably the worst scenario with patients experiencing symptoms from mechanical dysfunction and the risk of sudden death from rhythm disturbance, both in the form of ventricular tachycardias or atrioventricular heart block. The fascinating aspect of this disease is that, to this day, there is no consensus on the aetiology, no ‘biomarker’ to diagnose the disease and no significant advance in therapy from the long-standing use of steroids. Furthermore, the disease demonstrates different phenotypes in different races, has familial tendency, ‘clusters’ among close associates, and has been linked to numerous environmental (organic and inorganic) and infectious agents. One hundred years after sarcoidosis was first described, this disease spectrum remains one of the most mysterious of human diseases.

Prenatal anti-Ro antibody exposure, congenital complete atrioventricular heart block, and high-dose steroid therapy: impact on neurocognitive outcome in school-age children.

To determine the impact of prenatal exposure to maternal anti-Ro antibodies, slow fetal heart rate, and/or prolonged dexamethasone therapy for immune-mediated congenital atrioventricular heart block (CAVB) on the cognitive and academic performance of these children at school age. We performed a prospective, blinded assessment of the cognitive functioning of 3 cohorts of children ages 6-16 years with in utero exposure to maternal anti-Ro antibodies in the following groups: no CAVB and no prenatal dexamethasone treatment (n = 14), CAVB without prenatal treatment (n = 10), and CAVB with prenatal dexamethasone treatment (n = 16). Domains assessed included intelligence, visual perceptual and visual motor skills, auditory and visual attention, verbal learning and memory, visual memory, executive function, and behavior. All cohorts scored within the normal range and were not significantly different in terms of intelligence scores, verbal comprehension, perceptional reasoning, working memory, and processing speed. For children with CAVB who were treated prenatally, there were no significant associations between the neurocognitive function scores, the minimal fetal heart rate (range 47-80 beats per minute), and either the duration (range 2-15 weeks) or dosage (range 56-824 mg) of dexamethasone therapy. CAVB and transplacental treatment with dexamethasone was not associated with neurocognitive impairment in school-age children. Larger numbers of children are needed to validate our observation, and assessment of other cognitive abilities is warranted.

Evaluation and management of atrioventricular block in children.

Pediatric brady-dysrhythmias and conduction disorders are uncommon, but timely recognition and evaluation are critical. This review will highlight the key diagnostic and management steps for first, second, and third-degree atrioventricular heart block in pediatric patients. There is a breadth of acquired and often reversible causes of atrioventricular block in childhood. Recent advances in diagnostics and pacing therapies have led to improved outcomes. A thorough evaluation is required to determine when atrioventricular block requires treatment. In symptomatic or unstable patients, the management should focus on resuscitative measures, diagnostic testing, potential reversible causes, monitoring for progression, cardiac consultation and evaluating the need for definitive pacemaker placement.

Long-term Electrocardiography Recording with Holter Monitoring in 15 Donkeys

The heart rates (HR) and rhythms of 15 healthy donkeys of various ages, both sexes, and various breeds were analyzed throughout 24-hour Holter monitoring. The animals were evaluated at rest in their daily environment without the presence of investigators causing stress, using a three-channel digital Holter recorder. Analysis revealed a maximal HR range from 62.5 to 93.7 beats/min (mean, 72.50 ± 7.51 beats/min), whereas the minimal HR ranged from 29.7 to 42.2 beats/min (mean, 34.90 ± 4.22 beats/min). The daily mean HR was 47.55 ± 3.70 beats/min. The daytime mean HR was 49.39 ± 2.77 beats/min, whereas the night time rate was 46.22 ± 4.38 beats/min. Sinus bradycardia and sinus tachycardia were detected in 7 and 10 of 15 studied donkeys, respectively. Cardiac dysrhythmias due to high vagal tone such as sinoatrial heart block and second-degree atrioventricular heart block were occasionally recorded in 1 and 3 donkeys, respectively. A higher mean HR and fewer cardiac dysrhythmias were observed in donkeys than in horses and ponies at rest. These findings could be justified by differences in the autonomic nervous system tone.

Anesthetic Management at Implantation of Permanent Pacemaker for Newborn with Congenital Complete Heart Block

Complete atrioventricular heart block is defined as non-conduction of electrical impulses from atria to ventricles. Atrial pace, independent from ventricles, is higher. Complete atrioventricular heart block begins at intrauterin life in newborns and it is called congenital complete heart block. Heart rate is the most important factor determining cardiac output among children and especially newborns. Newborns with congenital complete heart block have lower heart rate (<60 beat/min) and carry heart failure risk. Heart block is usually irreversible and affected newborns require permanent cardiac pacemaker from first week of their life. Understanding cardiovascular pathophysiology and knowing therapeutic approaches to congenital complete heart block are very important during perioperative management of these patients. In this case report we discussed general anesthetic management during implantation of permanent pacemaker for a newborn with congenital complete heart block. Key Words: Anesthesia; Heart block; Newborn.

Effect of yohimbine on detomidine induced changes in behavior, cardiac and blood parameters in the horse

ObjectiveTo describe selected pharmacodynamic effects of detomidine and yohimbine when administered alone and in sequence. Study designRandomized crossover design. AnimalsNine healthy adult horses aged 9 ± 4 years and weighing 561 ± 56 kg. MethodsThree dose regimens were employed in the current study. 1) 0.03 mg kg−1 detomidine IV, 2) 0.2 mg kg−1 yohimbine IV and 3) 0.03 mg kg−1 detomidine IV followed 15 minutes later by 0.2 mg kg−1 yohimbine IV. Each horse received all three treatments with a minimum of 1 week between treatments. Blood samples were obtained and plasma analyzed for detomidine and yohimbine concentrations by liquid chromatography-mass spectrometry. Behavioral effects, heart rate and rhythm, glucose, packed cell volume and plasma proteins were monitored. ResultsYohimbine rapidly reversed the sedative effects of detomidine in the horse. Additionally, yohimbine effectively returned heart rate and the percent of atrio-ventricular conduction disturbances to pre-detomidine values when administered 15 minutes post-detomidine administration. Plasma glucose was significantly increased following detomidine administration. The detomidine induced hyperglycemia was effectively reduced by yohimbine administration. Effects on packed cell volume and plasma proteins were variable. Conclusions and clinical relevanceIntravenous administration of yohimbine effectively reversed detomidine induced sedation, bradycardia, atrio-ventricular heart block and hyperglycemia.

Neonatal lupus erythematosus and its clinical variability

Neonatal lupus erythematosus (NLE) is a rare disease affecting newborns that is caused by maternal autoantibodies transmitted across the placenta. The disease may affect the skin, the heart, and rarely the hepatobiliary or hematological systems. A serious complication affecting some patients with NLE is atrioventricular heart block (AV block). The clinical picture of cutaneous NLE varies considerably. NLE presents with confluent, scaly, periorbital erythema, or erythematous infiltrated plaques with central vesicles and lesions resembling seborrheic eczema or fungal infection. In any newborn with such skin lesions, NLE should be included in the differential diagnosis. Dermatologists play an important role in the diagnosis. We review different skin lesions occurring in neonatal lupus erythematosus based on five patients from our own clinic.

Congenital complete heart block and spinal anaesthesia for caesarean section.

Congenital complete heart block could be absolutely asymptomatic. Increased awareness of suspecting an atrioventricular heart block in patients with slow heart rate and electrocardiograph examination will ensure recognition of this problem. The possibility of sudden cardiac death in these patients should not be forgotten. The goal in the peri-operative anaesthetic management is to preserve the heart rate and maintain haemodynamic stability. Herein, we present a case of congenital complete heart block posted for elective caesarean section for an obstetric indication. We would like to highlight the advantage of bupivacaine–fentanyl combination in maintaining haemodynamic stability and peri-operative heart rate control with temporary pacemaker.

Poincaré plots and tachograms reveal beat patterning in sick sinus syndrome with supraventricular tachycardia and varying AV nodal block

Using 24-h ambulatory electrocardiography, the RR intervals of all beats were determined in a West Highland white terrier with sick sinus syndrome characterized by long sinus pauses, bradycardia, supraventricular tachycardia (SVT) and varying degrees of atrioventricular (AV) heart block. Distinctive patterns of bradycardia and 1:1, 2:1, 3:1, 4:1 and 5:1 AV block associated with SVT were evident in the tachogram (RR interval distribution over time) and Poincaré plots (short-term heart rate variability plots of RRn versus RRn + 1). These patterns differed from those of abrupt alteration in cycle length during long sinus pauses or bursts of supraventricular tachycardia. Recognition of such patterns may direct attention to time points for which close attention to the cardiac rhythm should be evaluated in the full-disclosure of the 24-h ECG recording.

Hemodialysis as an alternative treatment of mexiletine intoxication

Mexiletine is a class IB antiarrhythmic agent. Although it is primarily used in treating ventricular arrhythmias, recent indications for use of mexiletine include chronic and neuropathic pains. At high doses, mexiletine causes drowsiness, confusion, nausea, hypotension, sinus bradycardia, paresthesia, seizures, bundle branch block, atrioventricular heart block, ventricular arrhythmias, asystole, cardiovascular collapse, and coma. A 23-year-old male patient presented to the emergency department with intentional ingestion of high-dose mexiletine. Despite decontamination and supportive treatment, his vitals deteriorated during the observation period; and he developed stupor and dysarthria. Patient then underwent hemodialysis. His vital signs and overall condition improved rapidly following hemodialysis treatment. In this case report, we aimed to emphasize hemodialysis as a useful alternative therapy for severe mexiletine intoxications.

Complete AV block in Lyme carditis: an important differential diagnosis

Lyme disease is a tick-borne spirochetal infection that may affect the heart. Cardiac manifestations include conduction disturbances and other pathologies of the heart. We report on a 37-year old male, who was admitted to the emergency department because of dizziness and generalized tiredness. Physical examination and the initial laboratory values revealed no abnormalities. The patient's electrocardiogram on admission revealed newly diagnosed bradycardia due to atrioventricular heart block. The ventricular heart rate was 35/min. The patient was admitted to the ICU. Lyme serology and Western blot were positive for Borrelia antibodies. After institution of antibiotic therapy with ceftriaxone, atrioventricular heart block resolved rapidly. We therefore have to assume that in this patient Lyme carditis was the cause of third-degree AV block.

Dynamic Conduction Defects

Scenario: As a part of a screening regimen, a 24-hour ECG Holter was obtained on a 28-year-old healthy male firefighter. Three different time periods are shown below. The overall recording revealed a normal sinus rhythm with a heart rate range of 37–146/min. Baseline measurements included a blood pressure of 135/60 mm Hg and a body mass index of 31 kg/m2. The firefighter also successfully completed a graded exercise treadmill test using a Bruce protocol, achieving 100% of his maximum heart rate. Other than a previous history of smoking, he had no significant personal or familial medical history of cardiovascular diseases and does not take any medicine.Second degree heart block, Type 1 (T1 and T2), Type II (T3).The first ECG strip (T1) shows regularly irregular sinus bradycardia at rate of 42/min with second degree atrioventricular (AV) heart block Type 1 (also called Mobitz I or Wenchebach). It shows a progressive PR interval prolongation that eventually results in a dropped QRS complex before the cycle starts again. This condition is considered benign and always resembles a conduction defect of the AV node (70%) or His-Purkinje system (30%). Most are asymptomatic and the condition does not warrant further investigations. At T2 the same pattern is observed but the rhythm starts to show irregularly irregular sinus bradycardia (mixed 3:2 and 4:3 patterns). However, at T3 the rhythm shows a new onset first degree AV block with a fixed prolonged PR interval (400/ms) that is followed by a dropped QRS complex, referred to as second degree AV block Type 2 or Mobitz II: a conduction defect that occurs below the AV node. Those with Mobitz II are more likely to experience dizziness and syncope; the AV block is usually associated with right bundle branch block and is more likely to progress to third degree heart block. The prevalence of second degree heart blocks in young adults is as low as 0.003%; these are more prevalent in athletes, children with structural heart diseases, and postmyocardial infarctions. Sometimes they are due to certain medications (eg, beta-blockers).Whereas Mobitz I is not associated with increased risk of morbidity or mortality, Mobitz II is associated with an increased risk of mortality.These abnormalities seen in an asymptomatic firefighter may be related to the high vagal tone (athlete status); however, other etiologies need to be ruled out because cardiovascular diseases and sudden cardiac death account for 45% of on-duty deaths among firefighters. Although the recording was predominantly in normal sinus rhythm, the primary care provider should do a complete history and physical evaluation and refer the firefighter for a cardiology workup, even though he is asymptomatic.

Long-term Outcome and Risk of Heart Block After Surgical Treatment of Subaortic Stenosis

Although mortality following repair of subaortic obstruction is low, aggressive resection may increase morbidity. We sought to evaluate outcomes and risk of atrioventricular heart block (AVB) after subaortic resection in the current era. Simple obstruction was defined as a discrete subaortic membrane and complex as multilevel or diffuse narrowing. Limited resection included membranectomy and limited myomectomy. Aggressive resection included Konno, modified Konno, and Ross. Specified variables were obtained from a chart review. The 185 consecutive patients (1991-2008) ranged in age from 1 day to 21.8 years (5.1 ± 5.1 years) with 2 early and 4 late deaths. Actuarial survival was 97%, 95%, and 95% at 1, 5, and 10 years, respectively. Reoperations were required in 29 of 185 patients (15.7%); 2 required a third operation (1%). Freedom from reoperation in all patients was 97%, 83%, and 73% at 1, 5, and 10 years, respectively. Accessory mitral valve tissue (P < .001) and age <3 months (P = .004) predicted the need for reoperation. Transient or permanent high-degree AVB was documented in 33 of 185 patients (17.8%). Complex anatomy (P = .01) and aggressive resection (P < .001) increased the risk of acquiring AVB. The AVB was permanent in 21 of 185 (11.4%) patients, and pacemaker implantation was undertaken in 20 of 185 (10.8%) patients. Complex anatomy (P = .04) and modified Konno procedure (P = .03) increased the risk of acquiring a pacemaker. Aggressive resection lowered the frequency of recurrence but increased the risk of AVB. When aggressive resection is considered for long-term relief of subaortic obstruction, the risk of reobstruction must be balanced with the risk of AVB and the need for pacemaker implantation.

Transcatheter aortic valve implantation: role of multimodality cardiac imaging

Current evidence based on more than 8000 high-risk patients with severe aortic stenosis has demonstrated that transcatheter aortic valve implantation (TAVI) is a feasible alternative to surgical aortic valve replacement in selected patients. Despite current promising results on hemodynamic and clinical improvements, there are several unresolved safety issues, such as the frequency of vascular complications, postprocedural paravalvular leak, atrioventricular heart block and stroke. Multimodality cardiac imaging may help to minimize these complications and may play a central role before (optimizing patient selection, selection of appropriate prosthesis size and anticipating the procedural approach), during and after TAVI (evaluating the immediate and long-term procedural results). This article reviews the state-of-the-art TAVI procedures and the role that multimodality cardiac imaging plays before, during and after TAVI.

Heart damage in ankylosing spondylitis

Система комплексной поддержки и сопровождения научного журнала Elpub позволяет запустить двуязычный сайт журнала со встроенной системой электронной редакции в соответствии с лучшими издательскими практиками, а так же предусматривает техническую и методическую поддержку со стороны специалистов НЭИКОН.

Unknown ankylosing spondylitis with only cardiac involvement in patient with surgical indication: Call for patient and family members immunological screening

Aortic regurgitation (AR) and first-degree atrioventricular heart block (FDAVB) are encountered in ankylosing spondylitis (AS). This rheumatological disease also presents in 90% of the cases an immunogenetic marker that is Human Leucocyte Antigen-B27 (HLA-B27). In this report we describe a case of a patient presenting with AR, FDAVB, aneurysm and thinning of the ascending aortic wall, aneurysm of the sinuses of Valsalva and inferior myocardial infarction-like electrocardiographic pattern with unknown cardiac AS and absence of other AS-related systemic manifestations.