Risk and benefits of temporary pacemaker electrodes in adult open-heart surgery—a systematic review

Background To assess the achieved risk and benefits of inserting temporary epicardial pacemaker electrodes after open-heart surgery for potential treatment of postoperative cardiac arrhythmias, and to investigate the extent of its use in clinical practice. Main text A systematic search was conducted in PubMed and repeated in Embase and Scopus using the PRISMA guidelines. The search identified 905 studies and resulted in 12 included studies, where the type of surgery, study design, total number of included patients, number of patients having temporary pacemaker electrodes inserted, number of patients requiring temporary pacing, primary reason for pacing, significant factors predicting temporary pacing, registered complications and study conclusion were assessed. Eight papers concluded that routine insertion of temporary pacemaker electrodes in all postoperative patients is unnecessary. One paper concluded that they should always be inserted, while three papers concluded that pacing is useful in the postoperative period, but did not recommend a frequency of which they should be inserted. Conclusions The literature suggests that the subgroup of younger otherwise healthy patients without preoperative arrhythmia having isolated coronary artery bypass grafting surgery or single valve surgery should not routinely have temporary pacemaker electrodes inserted.

A case report of severe cardioinhibitory reflex syncope associated with COVID-19

Background Coronavirus disease 2019 (COVID-19) has been recognised as a disease with a broad spectrum of clinical manifestations. In this report we illustrate an extraordinary case of severe cardioinhibitory reflex syncope with prolonged asystole associated with COVID-19. Case summary A 35-year-old male patient presented to the emergency department with a ten-day history of postural syncope and fever. ECG monitoring during positional change revealed reflex syncope with cardioinhibitory response, exhibiting sinus bradycardia, subsequent asystole and transient loss of consciousness (TLOC). The patient tested positive for severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) and was admitted to the ICU where temporary transvenous pacing was necessary because of prolonged episodes of asystole. Work-up included extensive cardiac and neurological diagnostic testing, but did not yield any structural abnormalities. Although temporary pacing was able to abort syncope, a decision was made to hold off on permanent pacing as the most likely aetiology was felt to be temporary cardioinhibitory reflex syncope associated with COVID-19. The patient was discharged with mild symptoms of orthostatic intolerance and responded well to education and lifestyle modification. Outpatient follow-up with repeat tilt testing after three and six months initially showed residual inducible syncope but was eventually normal and the patient remained asymptomatic. Discussion We believe that autonomic imbalance with a strong vagal activation due to acute SARS-CoV-2 infection played a pivotal role in the occurrence of transient syncope in this patient’s condition. Although pacemaker implantation would have been a reasonable alternative, a watch-and-wait approach should be considered in similar instances.

The Wattson temporary pacing guidewire for transcatheter heart valve implantation

Transcatheter aortic valve implantation and implantation of other transcatheter heart valves, generally requires insertion of a temporary venous pacemaker. Implantation of a temporary venous pacemaker adds complexity, time and risk to the procedure. Guidewire modification to allow pacing is increasingly popular, however it requires technical expertise and provides unipolar pacing resulting in high thresholds and potential capture loss. The Wattson temporary pacing guidewire is a novel device which offers guidewire support for valve delivery and concomitant bipolar pacing. It may offer a safe and effective solution to guidewire pacing for transcatheter aortic valve implantation and other transcatheter heart valve implantations. Herein, we review the literature surrounding left ventricular guidewire pacing along with the features and clinical data of the Wattson wire.

Takotsubo syndrome and complete heart block, which came first? A case report

Background In 2018 the European society of cardiology published two consensus documents on takotsubo syndrome which include the current consensus on nomenclature, diagnosis, management and complications. However, little is mentioned on the association with complete heart block, except that “AV block [occurs in] 2.9% of cases”. Complete heart block is a recognised rare association of takotsubo syndrome, but causation is often unclear. Does complete heart block trigger takotsubo syndrome or vice-versa? Here we present a case of takotsubo syndrome associated with complete heart block. Case summary An 89-year-old woman presented with a transient loss of consciousness, acute chest pain and dyspnoea. A few days prior to this her daughter died suddenly of a myocardial infarction. On presentation troponin levels were elevated, the ECG showed complete heart block with a broad QRS and an echo showed apical akinesis and ballooning. Angiographic investigation excluded significant coronary artery disease. A dual chamber pacemaker was implanted after a brief period of temporary pacing. Ventricular function normalized during Follow-up and her underlying rhythm remained complete heart block. Discussion Takotsubo syndrome may be triggered by both emotional and physical stressors. Complete heart block is recognised association but causation is often unclear. In our case a clear emotional trigger was identified suggesting the takotsubo syndrome may have precipitated complete heart block not vice versa.

An unusual case of pediatric inflammatory multisystem syndrome, due to severe acute respiratory syndrome coronavirus-2 infection, presenting with complete heart block needing permanent pacing

Pediatric inflammatory multisystem syndrome due to severe acute respiratory syndrome coronavirus-2 infection is not very common. It may vary from a simple febrile inflammatory response to a severe multisystem involvement including myocarditis and shock. Here, we report the case of a 10-year-old female child with fever, rash, and mucositis who presented with shock and complete heart block along with encephalopathy and convulsions. The primary investigations revealed raised inflammatory markers along with a high titer of COVID antibodies. She was given full inotrope support along with immunomodulators. She underwent temporary pacing but ultimately needed a dual-chamber pacemaker. The novel coronavirus in children can present with a myriad of manifestations affecting almost every organ. In these pandemic times, one must always keep in mind the possibility of COVID-19 infection in a child that presents with shock, carditis, and arrhythmias. These children need intense immunosuppression and must be managed very aggressively

Implementing Biological Pacemakers: Design Criteria for Successful Transition From Concept to Clinic

Each heartbeat that pumps blood throughout the body is initiated by an electrical impulse generated in the sinoatrial node (SAN). However, a number of disease conditions can hamper the ability of the SAN′s pacemaker cells to generate consistent action potentials and maintain an orderly conduction path, leading to arrhythmias. For symptomatic patients, current treatments rely on implantation of an electronic pacing device. However, complications inherent to the indwelling hardware give pause to categorical use of device therapy for a subset of populations, including pediatric patients or those with temporary pacing needs. Cellular-based biological pacemakers, derived in vitro or in situ, could function as a therapeutic alternative to current electronic pacemakers. Understanding how biological pacemakers measure up to the SAN would facilitate defining and demonstrating its advantages over current treatments. In this review, we discuss recent approaches to creating biological pacemakers and delineate design criteria to guide future progress based on insights from basic biology of the SAN. We emphasize the need for long-term efficacy in vivo via maintenance of relevant proteins, source-sink balance, a niche reflective of the native SAN microenvironment, and chronotropic competence. With a focus on such criteria, combined with delivery methods tailored for disease indications, clinical implementation will be attainable.

Temporary pacing: an overview

This article will review pacing in the context of acute care, with a focus on temporary pacing. Beginning with an overview of the heart's intrinsic electrical conduction system and its function, the discussion moves on to pacing, acute clinical presentations and indications for pacing. This includes an overview of temporary pacing, with the different approaches being percussion, transcutaneous, transvenous and epicardial. There are specific cardiac patient groups at high risk of developing bradyarrhythmias and, in the absence of other measures, potentially requiring emergency pacing. These groups include patients who have experienced a myocardial infarction following cardiac surgery and post transcatheter aortic valve implant. Nurses providing care for patients with temporary transvenous wires need an understanding of the potential complications and to recognise indications for moving on to a permanent pacing system.

Cardiogenic shock with complete heart block secondary to dengue myocarditis requiring temporary pacing

This case illustrates acute myocarditis with complete heart block in a 13-year-old teenager as a rare complication of acute dengue illness. He required urgent temporary pacing with inotropic support and antifailure medications. Complete heart block in dengue myocarditis is an acute but reversible condition. A similar presentation in a dengue-endemic country or with a history of travelling to tropical countries warrants a suspicion of dengue infection.