Download the Free Unbound MEDLINE PubMed App to your smartphone or tablet.
Available for iPhone, iPad, iPod touch, and Android.
Third-degree block [keywords]
- Clinical outcome as a function of the PR-interval-there is virtue in moderation: data from the Duke Databank for cardiovascular disease. [JOURNAL ARTICLE]
- Europace 2014 Aug 27.
Recently, a U-shaped association between PR-interval and the risk of developing atrial fibrillation was described, with higher risk in patients with long and short PR-intervals. Little is known regarding the association of PR-interval duration and mortality. The objective of the current study was to explore the relationship between PR-interval and major cardiovascular outcomes in patients with known coronary heart disease.Patients in sinus rhythm, undergoing coronary angiography at Duke University Medical Center between 1989 and 2010, who had significant stenosis in at least one native coronary artery, were included. Patients with arrhythmia, second- or third-degree AV-block, QRS > 120 ms were excluded. A total of 9,637 patients were included (median age 63, IQR 55-71 years, 67% men). After adjustment for relevant covariates, the risk of a CV event increased with a decreasing PR-interval (10 ms decrements) for PR-interval values <162 ms (all-cause mortality; HR 1.057, 95% CI 1.019-1.096, P = 0.0030, composite of death or stroke; HR 1.047, 95% CI 1.011-1.085, P = 0.0095 and composite of cardiovascular death or cardiovascular rehospitalization; HR 1.032, 95% CI 1.002-1.063, P = 0.0387). No statistically significant changes in the risk associated with PR-interval for values >162 ms were seen for any of the studied endpoints.In patients with coronary heart disease, a prolongation of the PR-interval was not independently associated with poor outcomes, but a PR-interval shorter than normal was associated with increased all-cause mortality and other major cardiovascular events.
- Initial complications and factors related to prehospital mortality in acute myocardial infarction with ST segment elevation. [JOURNAL ARTICLE]
- Emerg Med J 2014 Jul 25.
Hospital mortality in myocardial infarction ST-elevation myocardial infarction has decreased in recent years, in contrast to prehospital mortality. Our objective was to determine initial complications and factors related to prehospital mortality in patients with acute myocardial infarction with ST segment elevation (STEMI).Observational study based on a prospective continuous register of patients of any age attended by out-of-hospital emergency teams in Andalusia between January 2006 and June 2009. This includes patients with acute coronary syndrome-like symptoms whose initial ECG showed ST elevation or presumably new left bundle branch block (LBBB). Epidemiological, prehospital data and final diagnostic were recorded. The study included all patients with STEMI on the register, without age restrictions. Forward stepwise logistic regression analysis was performed to control for confounders.A total of 2528 patients were included, 24% were women. Mean age 63.4±13.4 years; 16.7% presented atypical clinical symptoms. Initial complications: ventricular fibrillation (VF) 8.4%, severe bradycardia 5.8%, third-degree atrial-ventricular (AV) block 2.4% and hypotension 13.5%. Fifty-two (2.1%) patients died before reaching hospital. Factors associated with prehospital mortality were female sex (OR 2.36, CI 1.28 to 4.33), atypical clinical picture (OR 2.31, CI 1.21 to 4.41), hypotension (OR 4.95, CI 2.60 to 9.20), LBBB (OR 4.29, CI 1.71 to 10.74), extensive infarction (ST elevation in ≥5 leads) (OR 2.53, CI 1.28 to 5.01) and VF (OR 2.82, CI 1.38 to 5.78).A significant proportion of patients with STEMI present early complications in the prehospital setting, and some die before reaching hospital. Prehospital mortality was associated with female sex and atypical presentation, as pre-existing conditions, and hypotension, extensive infarction, LBBB and VF on emergency team attendance.
- Prevention and Treatment in Utero of Autoimmune Associated Congenital Heart Block. [JOURNAL ARTICLE]
- Cardiol Rev 2014 Jul 21.
Transplacental transfer of maternal anti-Ro and/or anti-La autoantibodies can result in fetal cardiac disease including congenital heart block and cardiomyopathy, called cardiac Neonatal Lupus (NL). Thousands of women are faced with the risk of cardiac NL in their offspring, which is associated with significant morbidity and mortality. There are no known therapies to permanently reverse third degree heart block in NL, although several treatments have shown some effectiveness in incomplete heart block and disease beyond the atrioventricular node. Fluorinated steroids taken during pregnancy have shown benefit in these situations, although adverse effects may be concerning. Published data are discordant on the efficacy of fluorinated steroids in the prevention of mortality in cardiac NL. β-agonists have been used to increase fetal heart rates in utero. The endurance of β-agonist effect and its impact on mortality are in question, but when used in combination with other therapies, they may provide benefit. No controlled experiments regarding the use of plasmapheresis in cardiac NL have been performed, despite its theoretical benefits. Intravenous immunoglobulin was not shown to prevent cardiac NL at a dose of 400 mg/kg, although it has shown effectiveness in the treatment of associated cardiomyopathy both in utero and after birth. Retrospective studies have shown that hydroxychloroquine may prevent the recurrence of cardiac NL in families with a previously affected child, and a prospective open-label trial is currently recruiting patients in order to fully evaluate this relationship.
- Simultaneous Transcatheter Treatment of Perimembranous Ventricular Septal Defect And Other Congenital Cardiopathies. [JOURNAL ARTICLE]
- Heart Lung Circ 2014 Jun 17.
To assess the efficacy and safety of simultaneous transcatheter corrections of perimembranous ventricular septal defect (VSD) and other congenital cardiopathies.From 2004 to 2012, 56 patients (25 male, 31 female), aged 14.2±10.1, with compound congenital cardiovascular abnormalities underwent simultaneous transcatheter interventional procedure. Of the 56 patients, 32 had VSD and atrial septal defects (ASD); 17 had VSD and patent ductus arteriosus (PDA); and seven had VSD and pulmonary valve stenosis (PS). Percutaneous balloon pulmonary valvuloplasty (PBPV) was performed before the closure of VSD, PDA, or ASD.The combined transcatheter interventional procedure was successfully performed in all patients. Among these, two occluders were implanted in each of 49 patients, seven patients with VSD combined with PS underwent successfully balloon valvuloplasty and VSD closure. The size of VSD, ASD and PDA detected by TTE was 4.8±1.7mm, 9.0±5.0mm and 4.5±2.5mm, respectively. The occluder diameter of VSD, ASD and PDA was 7.6±2.2mm, 14.3±6.2mm and 7.9±3.2mm, respectively. The peak-to-peak transpulmonary gradient decreased from 60.4±19.7mmHg to 15.0±5.0mmHg (p<0.001) in seven patients with VSD combined with PS. One patient with VSD and ASD had a permanent pacemaker implanted because of third-degree atrioventricular block two months after the procedure. There were not serious adverse events in relation to the combined procedures during the 23.8±20.7 months of follow-up in other 55 patients.The simultaneous treatment of VSD and other congenital cardiopathies using transcatheter-based procedures is safe and effective, which can provide satisfactory results.
- Outcomes of fetal echocardiographic surveillance in anti-SSA exposed fetuses at a large fetal cardiology center. [JOURNAL ARTICLE]
- Prenat Diagn 2014 Jul 3.
Echocardiography screening in anti-SSA antibody exposed fetuses is controversial.Evaluate utility of fetal echocardiography in anti-SSA exposure.Echocardiograms done over 9 years for maternal anti-SSA exposure were reviewed for AV block, cardiomyopathy, arrhythmias, effusion, valve abnormalities, or other abnormalities identified by the echocardiographer. Fetuses with AV block referred to our institution and subsequently found to be anti-SSA exposed were also identified.Six hundred thirty six echocardiograms were performed on 140 fetuses (Cohort 1) of 134 women screened for maternal anti-SSA +/- anti-SSB antibodies. No fetuses developed second or third degree AV block or cardiomyopathy (odds ratio 0.1, CI 0.0051 to 1.9410, p=0.13). Dexamethasone was administered to three fetuses for sinus bradycardia, echogenicity near AV node, and ventricular systolic dysfunction with valve regurgitation; all normalized. Screening echocardiograms identified: sinus bradycardia (n=1), PR prolongation (n=5), premature atrial contractions (n=3), valve regurgitation (n=24), echogenic myocardium (n=4), and pericardial effusion (n=1). Isolated tricuspid regurgitation and first degree AV block did not progress. Nine cases of SSA-mediated AV block (Cohort 2) were referred after heart block developed.Serial fetal echocardiography in anti-SSA exposed fetuses did not detect AV block. In rare cases, dexamethasone treatment may have affected disease course. This article is protected by copyright. All rights reserved.
- Autonomic etiology of heart block in amyotrophic lateral sclerosis: a case report. [JOURNAL ARTICLE]
- J Med Case Rep 2014 Jun 24; 8(1):224.
The cardiovascular consequences related to amyotrophic lateral sclerosis are relatively underappreciated. The disease invokes a systematic degeneration of autonomic neurons leading to autonomic dysfunction. We therefore hypothesized that patients with amyotrophic lateral sclerosis may have a predilection to the development of cardiac conduction disorders.A 65-year-old Caucasian man with advanced amyotrophic lateral sclerosis presented with progressive dyspnea and palpitations. A previous evaluation attributed his dyspnea to neuromuscular weakness and he underwent a pulmonary evaluation. Pulmonary function tests did not indicate a worsening from baseline. An electrocardiogram was obtained which demonstrated new third degree atrioventricular block. A previously obtained electrocardiogram indicated normal sinus rhythm. On echocardiogram, a structurally normal heart was observed without significant valvular disease. He was offered a permanent dual chamber pacemaker for definitive treatment, however, he declined.We believe that his symptoms were probably attributable to atrioventricular block. Patients with advanced amyotrophic lateral sclerosis experience loss of heart rate variability and enhanced vasomotor responses. As patients progress later in the disease, sympathetic denervation and vagal predominance contribute to the development of atrioventricular block. We conducted a query using the Explorys database of patients with amyotrophic lateral sclerosis and heart block. The prevalence of heart block was estimated to be 25% higher in patients with the disease as compared to the general population. This is the first reported case that attempts to describe the relationship of atrioventricular block with amyotrophic lateral sclerosis.
- Anaesthetic management and complications of pacemaker implantation in dogs. [JOURNAL ARTICLE]
- Vet Rec 2014 Jun 23.
The aim of this study was to report the anaesthetic management and peri-anaesthetic complications of 57 dogs undergoing pacemaker implantation at a referral institution over 10 years (2002-2012). The median duration of the procedure was 135 minutes (range 25-260 minutes). Patients were classified as American Society of Anaesthesiologist (ASA) III (42 cases) and ASA IV (15 cases). Forty-three patients had third-degree atrioventricular block, and 14 patients had sick sinus syndrome. The anaesthetic protocol most frequently chosen was pethidine (41 cases), etomidate-midazolam (43 cases) and isoflurane in oxygen for maintenance (57 cases). Transthoracic external pacing was used (43 cases) until the internal pacing lead was implanted. Atracurium was administered (48 cases) and intermittent positive pressure ventilation was applied in 52 cases. Complications observed included hypothermia (19 cases) and hypotension (5 cases). Three patients died (5.8%, 95% CI 1.1% to 14.6%) within the first 48 hours after termination of anaesthesia. The outcome for this procedure in sick animals appeared generally good though a number of complications were documented.
- Pattern of cardiothoracic surgical diseases in a new cardiothoracic surgery unit in Nigeria. [Journal Article]
- Niger J Med 2014 Jan-Mar; 23(1):77-82.
Cardiothoracic surgical pathologies are available in all geographical regions of the world. Human and material resources are necessary for prompt diagnosis and proper treatment of these cases.Retrospective analysis of cardiothoracic surgical cases in the first five years of our new cardiothoracic surgery unit was done.A total of 714 cases were seen during the study period with age range one month to 76 years with mean age of 37.12 +/- 11.24 and male female ratio of 2:1. The yearly admissions from 2007 to 2011 were 14%, 17%, 21%, 21% and 26% respectively. Cardiovascular diseases occurred in 22.30%, with 6% of children suffering from congenital heart defect and 6% of men suffering from acquired vascular disease. Surgical complications of pleuropulmonary tuberculosis occurred in 21.4% while thoracic trauma occurred in upto 21% of the patients. Aerodigestive tract foreign bodies were encountered in 10.1% of cases and Pyogenic diseases occurred in 8.68%. Oesophageal lesions were diagnosed in 6.4% of the patients, pulmonary tumours including primary and secondary tumours were found in 4.3% while nontraumatic chest wall pathologies which included chest wall tumours, congenital deformities and chronic osteomyelities accounted for 3.2%. Mediastinal pathologies occurred in 0.98% and in the remaining 1.5% rare diseases were diagnosed such as third degree heart block, pulmonary embolism and thoracic endometriosis syndrome.This study shows that cardiothoracic surgical pathologies are common in our centre with predominance of thoracic pathologies, and therefore need to prioritize and ensure manpower development for treatment of all kinds of thoracic pathologies.
- Predictors of advanced His-Purkinje conduction disturbances in patients with unexplained syncope and bundle branch block. [Journal Article, Multicenter Study]
- Can J Cardiol 2014 Jun; 30(6):606-11.
For patients presenting with syncope and bundle branch block (BBB), results during electrophysiological studies (EPS) might depend on the electrocardiographic pattern of conduction disturbances. We sought to identify predictors of advanced His-Purkinje conduction disturbances (HPCDs) in these patients.In this retrospective multicentre study, patients were included who: (1) presented with unexplained syncope; (2) had BBB (QRS duration ≥ 120 ms); and (3) were investigated with EPS. HPCD was diagnosed if the baseline His-ventricular interval was ≥ 70 ms or if second- or third-degree His-Purkinje block was observed during atrial pacing or pharmacological challenge.Of the 171 patients studied (72 ± 13 years, 64% male sex, mean left ventricular ejection fraction 57 ± 9%), advanced HPCD was found in 73 patients (43%). The following electrocardiographic features were associated with HPCD (P = 0.01): isolated right BBB (34.4%), right BBB with left anterior fascicular block (36.4%), left BBB (46.2%), and right BBB with left posterior fascicular block (LPFB, 78.6%). Multivariate analysis identified first-degree atrioventricular block (odds ratio, 2.4; 95% confidence interval, 1.2-4.7; P = 0.01) and LPFB (odds ratio, 4.8; 95% confidence interval, 1.3-18.5; P = 0.02) as the only 2 independent predictors of advanced HPCD.For patients presenting with syncope and BBB, first-degree atrioventricular block and LPFB increased the likelihood of finding HPCDs during EPS. However, no single electrocardiographic feature could consistently predict the outcome of EPS, so this investigation is still necessary in assessing the need for pacemaker implantation, irrespective of the precise appearance of abnormalities on ECG.
- Third-Degree Heart Block Associated with Lyme Carditis: Review of Published Cases. [JOURNAL ARTICLE]
- Clin Infect Dis 2014 May 30.
Lyme carditis is an uncommon manifestation of Lyme disease that most commonly involves some degree of atrioventricular conduction blockade. Third-degree conduction block is the most severe form and can be fatal if untreated. Systematic review of the medical literature identified 45 published cases of third-degree conduction block associated with Lyme carditis in the United States. Median patient age was 32 years, 84% of patients were male, and 39% required temporary pacing. Recognizing patient groups more likely to develop third-degree heart block associated with Lyme carditis is essential to providing prompt and appropriate therapy.