Sinus Bradycardia Publications (4161)


Sinus Bradycardia Publications

J. Cardiovasc. Electrophysiol.
J Cardiovasc Electrophysiol 2016 Dec 29. Epub 2016 Dec 29.
Vrije Universiteit Brussel, Universitair Ziekenhuis Brussel, Centre for Cardiovascular Diseases, B1090, Brussels, Belgium.
Case Rep Cardiol
Case Rep Cardiol 2016 24;2016:9785467. Epub 2016 Nov 24.
Baltimore VA Medical Center, Surgical Intensive Care Unit, 10 North Greene Street, 5C-119, Baltimore, MD 21201, USA.

Steroids are used for specific indications in the perioperative period to reduce laryngeal or spinal cord edema, or for prophylaxis and treatment of postoperative nausea and vomiting. Given the other potential causes for hemodynamic alterations in the perioperative setting, it is important for physicians to be aware of cardiovascular side effects of short term steroids. Changes in blood pressure and heart rate, cardiac dysrhythmias, and even death have been described in patients receiving short term intravenous steroids. Read More

Bradycardia has been reported following short term methylprednisolone and dexamethasone therapy in both adult and pediatric patients. There are only two case reports in the literature of bradycardia following short term intravenous dexamethasone use in adult patients. This is the first case report that describes bradycardia following the use of dexamethasone in the postoperative setting for management of laryngeal edema in an adult. Telemetry and twelve lead electrocardiograms revealed sinus bradycardia and correlated directly with administration of dexamethasone in our patient. Bradycardia resolved following discontinuation of dexamethasone. We advocate for hemodynamic monitoring in patients receiving more than one dose of intravenous steroid therapy in the perioperative period, especially those with known cardiac and hepatic comorbidities and those taking medications with negative chronotropic effects.

J Pharm Pract
J Pharm Pract 2016 Dec 5. Epub 2016 Dec 5.
Department of Cardiology, The University of Chicago Medicine, Chicago, IL, USA.
J Atr Fibrillation
J Atr Fibrillation 2016 Apr-May;8(6):1396. Epub 2016 Apr 30.
Division of Cardiovascular Medicine, University of Iowa Hospitals and Clinics, Iowa City, Iowa.

In patients known to be a high risk for sudden cardiac arrest, implantable cardioverter defibrillators (ICD) are a proven therapy to reduce risk of death. However, in patients without conventional indications for pacing, the optimal strategy for type of device, dual- versus single-chamber, remains debatable. The benefit of prophylactic pacing in this category of patients has never been documented. Read More

Although available atrial electrograms in a dual chamber system improve interpretation of stored arrhythmia events, allow monitoring of atrial fibrillation and may potentially reduce the risk of inappropriate shocks by enhancing automated arrhythmia discrimination, the use of dual-chamber ICDs has a number of disadvantages. The addition of an atrial lead adds complexity to implantation and extraction procedures, increases procedural cost and is associated with a higher risk of periprocedural complications. The single lead pacing system with ability to sense atrial signals via floating atrial electrodes (VDD) clinically became available in early 1980's but did not gain much popularity due to inconsistent atrial sensing and concerns about the potential need for an atrial lead if sinus node fails. Most ICD patients do not have indications for pacing at implantation and subsequent risk of symptomatic bradycardia seems to be low. The concept of atrial sensing via floating electrodes has recently been revitalized in the Biotronik DX ICD system (Biotronik, SE & Co., Berlin, Germany) aiming to provide all of the potential advantages of available atrial electrograms without the risks and incremental cost of an additional atrial lead. Compared to a traditional VDD pacing system, the DX ICD system uses an optimized (15 mm) atrial dipole spacing and improved atrial signal processing to offer more reliable atrial sensing. The initial experience with the DX system indicates that the clinically useful atrial signal amplitude in sinus rhythm remains stable over time. Future studies are needed to determine reliability of atrial sensing during tachyarrhythmias, particularly atrial fibrillation as well as clinical utility and cost-effectiveness of this technology in different populations of patients.

Cochrane Database Syst Rev
Cochrane Database Syst Rev 2016 11 22;11:CD012088. Epub 2016 Nov 22.
Institute of Health Informatics, University College London, 222 Euston Road, London, UK, NW1 2DA.

The optimal rhythm management strategy for people with non-paroxysmal (persistent or long-standing persistent) atrial fibrilation is currently not well defined. Antiarrhythmic drugs have been the mainstay of therapy. But recently, in people who have not responded to antiarrhythmic drugs, the use of ablation (catheter and surgical) has emerged as an alternative to maintain sinus rhythm to avoid long-term atrial fibrillation complications. Read More

However, evidence from randomised trials about the efficacy and safety of ablation in non-paroxysmal atrial fibrillation is limited.
To determine the efficacy and safety of ablation (catheter and surgical) in people with non-paroxysmal (persistent or long-standing persistent) atrial fibrillation compared to antiarrhythmic drugs.
We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE Ovid, Embase Ovid, conference abstracts, clinical trial registries, and Health Technology Assessment Database. We searched these databases from their inception to 1 April 2016. We used no language restrictions.
We included randomised trials evaluating the effect of radiofrequency catheter ablation (RFCA) or surgical ablation compared with antiarrhythmic drugs in adults with non-paroxysmal atrial fibrillation, regardless of any concomitant underlying heart disease, with at least 12 months of follow-up.
Two review authors independently selected studies and extracted data. We evaluated risk of bias using the Cochrane 'Risk of bias' tool. We calculated risk ratios (RRs) for dichotomous data with 95% confidence intervals (CIs) a using fixed-effect model when heterogeneity was low (I² <= 40%) and a random-effects model when heterogeneity was moderate or substantial (I² > 40%). Using the GRADE approach, we evaluated the quality of the evidence and used the GRADE profiler (GRADEpro) to import data from Review Manager 5 to create 'Summary of findings' tables.
We included three randomised trials with 261 participants (mean age: 60 years) comparing RFCA (159 participants) to antiarrhythmic drugs (102) for non-paroxysmal atrial fibrillation. We generally assessed the included studies as having low or unclear risk of bias across multiple domains, with reported outcomes generally lacking precision due to low event rates. Evidence showed that RFCA was superior to antiarrhythmic drugs in achieving freedom from atrial arrhythmias (RR 1.84, 95% CI 1.17 to 2.88; 3 studies, 261 participants; low-quality evidence), reducing the need for cardioversion (RR 0.62, 95% CI 0.47 to 0.82; 3 studies, 261 participants; moderate-quality evidence), and reducing cardiac-related hospitalisation (RR 0.27, 95% CI 0.10 to 0.72; 2 studies, 216 participants; low-quality evidence) at 12 months follow-up. There was substantial uncertainty surrounding the effect of RFCA regarding significant bradycardia (or need for a pacemaker) (RR 0.20, 95% CI 0.02 to 1.63; 3 studies, 261 participants; low-quality evidence), periprocedural complications, and other safety outcomes (RR 0.94, 95% CI 0.16 to 5.68; 3 studies, 261 participants; very low-quality evidence).
In people with non-paroxysmal atrial fibrillation, evidence suggests a superiority of RFCA to antiarrhythmic drugs in achieving freedom from atrial arrhythmias, reducing the need for cardioversion, and reducing cardiac-related hospitalisations. There was uncertainty surrounding the effect of RFCA with significant bradycardia (or need for a pacemaker), periprocedural complications, and other safety outcomes. Evidence should be interpreted with caution, as event rates were low and quality of evidence ranged from moderate to very low.


Paroxysmal atrioventricular block (PAVB) is rare in children. A 1-year-old boy presented with PAVB and sinus arrest that resulted in refractory life-threatening symptomatic long pauses. Continuous heart rate variability analysis with high time resolution (wavelet analysis) revealed an abrupt increase in parasympathetic activity just before a long pause, which indicated a vagal reflex. Read More

Although a pacemaker is not always effective because of a concomitant vasodepressive response in such cases, the complete stabilization after pacemaker implantation in this case supports the necessity and usefulness of pacemaker implantation in patients with reflex-induced highly symptomatic bradycardia.

Case Rep Cardiol
Case Rep Cardiol 2016 19;2016:9805291. Epub 2016 Oct 19.
Department of Internal Medicine, Cardiovascular Division, Hyogo College of Medicine, Nishinomiya, Japan.

Anorexia nervosa (AN) is an eating disorder characterized by an abnormally low body weight, an intense fear of gaining weight, and a distorted perception of body weight. AN is a life-threatening condition that significantly increases the risk of death due to cardiac complications, such that at least one-third of all deaths in patients with AN are associated with cardiac causes including sudden death. In many reports, sudden death has been linked to reduced left ventricular function, structural changes, and QT abnormalities. Read More

However, the mechanistic details connecting AN to cardiac abnormalities remain unknown. Here we present an endomyocardial biopsy of the left ventricle in a case of AN with a reversible left ventricular systolic dysfunction.