Takotsubo Syndrome After Pacemaker Implantation: A Case Report and Literature Review.

A 78-year-old male patient with complete atrioventricular block underwent an uncomplicated pacemaker implantation. After 24 h, he presented acute chest pain, dyspnea, ST-segment-elevation in the anterior leads, left ventricular apical ballooning, and an ejection fraction of 35%. His coronary angiogram was normal. Within 2 days, his symptoms and electrocardiogram (ECG) abnormalities disappeared, while wall motion abnormalities recovered after 6 weeks. A diagnosis of takotsubo syndrome (TTS) was made. Pacemaker implantation has been described as a potential trigger for TTS. The clinical picture exhibits some peculiarities, including a higher percentage of men and asymptomatic patients and challenging ST-segment interpretation of paced ECGs. It is unclear whether pathophysiologic mechanisms are different compared to other forms of TTS and whether the acute initiation of ventricular pacing plays a role.

SCN5A mutation is associated with a higher Shanghai Score in patients with type 1 Brugada ECG pattern.

AIMS: Brugada syndrome (BrS) is an inherited arrhythmic disease characterized by a coved ST-segment elevation in the right precordial electrocardiogram leads (type 1 ECG pattern) and is associated with a risk of malignant ventricular arrhythmias and sudden cardiac death. In order to assess the predictive value of the Shanghai Score System for the presence of a SCN5A mutation in clinical practice, we studied a cohort of 125 patients with spontaneous or fever/drug-induced BrS type 1 ECG pattern, variably associated with symptoms and a positive family history. METHODS: The Shanghai Score System items were collected for each patient and PR and QRS complex intervals were measured. Patients were genotyped through a next-generation sequencing (NGS) custom panel for the presence of SCN5A mutations and the common SCN5A polymorphism (H558R). RESULTS: The total Shanghai Score was higher in SCN5A+ patients than in SCN5A- patients. The 81% of SCN5A+ patients and the 100% of patients with a SCN5A truncating variant exhibit a spontaneous type 1 ECG pattern. A significant increase in PR (P = 0.006) and QRS (P = 0.02) was detected in the SCN5A+ group. The presence of the common H558R polymorphism did not significantly correlate with any of the items of the Shanghai Score, nor with the total score of the system. CONCLUSION: Data from our study suggest the usefulness of Shanghai Score collection in clinical practice in order to maximize genetic test appropriateness. Our data further highlight SCN5A mutations as a cause of conduction impairment in BrS patients.

Dynamic changes in T-wave and QTc interval during tilt table testing: Innocent until proven otherwise.

A16-year-old female underwent tilt table testing, which resulted positive for reflex vasodepressive syncope. 12­lead ECG during syncope showed T-wave inversion in infero-lateral leads, along with QTc interval increase >100 msec compared to baseline. These abnormalities rapidly disappeared in supine position with resumption of consciousness. Complete cardiac evaluation excluded heart disease. T-wave changes and moderate QTc prolongation are relatively common in young (mainly female) patients undergoing tilt table testing and they appear benign in nature. However, in a minority of cases, on the basis of the clinical context and after an accurate ECG analysis, further examinations may be warranted.

Brugada ECG pattern in hypertrophic cardiomyopathy: Brugada phenocopy or overlapping syndrome?

The term phenocopy indicates a condition that imitates one produced by a gene and is also used for acquired Brugada-like ECG manifestations. Cases of Brugada phenocopies are increasingly reported in literature and an international registry is ongoing. We describe two patients with Hypertrophic Cardiomyopathy (HCM) and Brugada ECG pattern. Both patients carried the same pathogenic splicing mutation in MYBPC3 gene (responsible for HCM) while no genetic mutation associated with Brugada Syndrome was identified. To the best of our knowledge, Brugada ECG pattern has been rarely reported in patients with HCM.

The role of atrial sensing for new-onset atrial arrhythmias diagnosis and management in single-chamber implantable cardioverter-defibrillator recipients: Results from the THINGS registry.

INTRODUCTION: Atrial tachycardia/fibrillation (AT/AF) episodes are common in implantable cardioverter-defibrillator (ICD) recipients and can be undetected by standard single-chamber devices. This study aims to explore whether a single-lead ICD with an atrial dipole (ICD DX; BIOTRONIK SE & Co, Berlin, Germany) could improve the AT/AF diagnosis and management as compared to standard ICD (ICD VR). METHODS AND RESULTS: We selected patients without AT/AF history from the THINGS registry which included consecutive patients implanted with ICD for standard indications. The ICD VR and the ICD DX groups included 236 (62.8%) and 140 (37.2%) patients, respectively, and had no significant differences in baseline characteristics. During a median follow-up of 27 months, there were 7 AT/AF diagnoses in the ICD VR and 18 in the ICD DX group. The 2-year incidence of AT/AF diagnosis was 3.6% (95% confidence interval [CI]: 1.6%-9.6%) for the ICD VR and 11.4% (95% CI: 6.8%-18.9%) for the ICD DX group (adjusted hazard ratio [HR]: 3.85 [95% CI: 1.58-9.41]; P = .003). Initiation of oral anticoagulation (OAC) due to AT/AF diagnosis was reported in 15 patients. The 2-year incidence of OAC onset was 3.6% (95% CI: 1.6%-7.8%) for the ICD VR and 6.3% (95% CI: 3.0%-12.7%) for ICD DX group (adjusted HR: 1.99 [95% CI: 0.72-5.56]; P = .184). CONCLUSION: We observed that atrial sensing capability in single-chamber ICD patients without evidence of atrial arrhythmias at implant is associated with a greater likelihood of detecting AT/AF episodes. The management of these diagnosed arrhythmias often led to clinical interventions, mainly represented by initiation of OAC therapy.

Diagnosis and risk stratification of chest pain patients in the emergency department: focus on acute coronary syndromes. A position paper of the Acute Cardiovascular Care Association.

This paper provides an update on the European Society of Cardiology task force report on the management of chest pain. Its main purpose is to provide an update on the decision algorithms and diagnostic pathways to be used in the emergency department for the assessment and triage of patients with chest pain symptoms suggestive of acute coronary syndromes.

Cardiac arrhythmias in the emergency settings of acute coronary syndrome and revascularization: an European Heart Rhythm Association (EHRA) consensus document, endorsed by the European Association of Percutaneous Cardiovascular Interventions (EAPCI), and European Acute Cardiovascular Care Association (ACCA).

Despite major therapeutic advances over the last decades, complex supraventricular and ventricular arrhythmias (VAs), particularly in the emergency setting or during revascularization for acute myocardial infarction (AMI), remain an important clinical problem. Although the incidence of VAs has declined in the hospital phase of acute coronary syndromes (ACS), mainly due to prompt revascularization and optimal medical therapy, still up to 6% patients with ACS develop ventricular tachycardia and/or ventricular fibrillation within the first hours of ACS symptoms. Despite sustained VAs being perceived predictors of worse in-hospital outcomes, specific associations between the type of VAs, arrhythmia timing, applied treatment strategies and long-term prognosis in AMI are vague. Atrial fibrillation (AF) is the most common supraventricular tachyarrhythmia that may be asymptomatic and/or may be associated with rapid haemodynamic deterioration requiring immediate treatment. It is estimated that over 20% AMI patients may have a history of AF, whereas the new-onset arrhythmia may occur in 5% patients with ST elevation myocardial infarction. Importantly, patients who were treated with primary percutaneous coronary intervention for AMI and developed AF have higher rates of adverse events and mortality compared with subjects free of arrhythmia. The scope of this position document is to cover the clinical implications and pharmacological/non-pharmacological management of arrhythmias in emergency presentations and during revascularization. Current evidence for clinical relevance of specific types of VAs complicating AMI in relation to arrhythmia timing has been discussed.

Editor's Choice - Acute Cardiovascular Care Association Position Paper on Intensive Cardiovascular Care Units: An update on their definition, structure, organisation and function.

Acute cardiovascular care has progressed considerably since the last position paper was published 10 years ago. It is now a well-defined, complex field with demanding multidisciplinary teamworking. The Acute Cardiovascular Care Association has provided this update of the 2005 position paper on acute cardiovascular care organisation, using a multinational working group. The patient population has changed, and intensive cardiovascular care units now manage a large range of conditions from those simply requiring specialised monitoring, to critical cardiovascular diseases with associated multi-organ failure. To describe better intensive cardiovascular care units case mix, acuity of care has been divided into three levels, and then defining intensive cardiovascular care unit functional organisation. For each level of intensive cardiovascular care unit, this document presents the aims of the units, the recommended management structure, the optimal number of staff, the need for specially trained cardiologists and cardiovascular nurses, the desired equipment and architecture, and the interaction with other departments in the hospital and other intensive cardiovascular care units in the region/area. This update emphasises cardiologist training, referring to the recently updated Acute Cardiovascular Care Association core curriculum on acute cardiovascular care. The training of nurses in acute cardiovascular care is additionally addressed. Intensive cardiovascular care unit expertise is not limited to within the unit's geographical boundaries, extending to different specialties and subspecialties of cardiology and other specialties in order to optimally manage the wide scope of acute cardiovascular conditions in frequently highly complex patients. This position paper therefore addresses the need for the inclusion of acute cardiac care and intensive cardiovascular care units within a hospital network, linking university medical centres, large community hospitals, and smaller hospitals with more limited capabilities.

Cardiac magnetic resonance imaging: Which information is useful for the arrhythmologist?

Cardiac magnetic resonance (CMR) is a non-invasive, non-ionizing, diagnostic technique that uses magnetic fields, radio waves and field gradients to generate images with high spatial and temporal resolution. After administration of contrast media (e.g., gadolinium chelate), it is also possible to acquire late images, which make possible the identification and quantification of myocardial areas with scar/fibrosis (late gadolinium enhancement, LGE). CMR is currently a useful instrument in clinical cardiovascular practice for the assessment of several pathological conditions, including ischemic and non-ischemic cardiomyopathies and congenital heart disease. In recent years, its field of application has also extended to arrhythmology, both in diagnostic and prognostic evaluation of arrhythmic risk and in therapeutic decision-making. In this review, we discuss the possible useful applications of CMR for the arrhythmologist. It is possible to identify three main fields of application of CMR in this context: (1) arrhythmic and sudden cardiac death risk stratification in different heart diseases; (2) decision-making in cardiac resynchronization therapy device implantation, presence and extent of myocardial fibrosis for left ventricular lead placement and cardiac venous anatomy; and (3) substrate identification for guiding ablation of complex arrhythmias (atrial fibrillation and ventricular tachycardias).

Antitachycardia pacing programming in implantable cardioverter defibrillator: A systematic review.

Implantable cardioverter defibrillator (ICD) programming involves several parameters. In recent years antitachycardia pacing (ATP) has gained an increasing importance in the treatment of ventricular arrhythmias, whether slow or fast. It reduces the number of unnecessary and inappropriate shocks and improves both patient's quality of life and device longevity. There is no clear indication regarding the type of ATP to be used, except for the treatment of fast ventricular tachycardias (188 bpm-250 bpm) where it has been shown a greater efficacy and safety of burst compared to ramp; 8 impulses in each sequence of ATP appears to be the best programming option in this setting. Beyond ATP use, excellent clinical results were obtained with programming standardization following these principles: extended detection time in ventricular fibrillation (VF) zone; supraventricular discrimination criteria up to 200 bpm; first shock in VF zone at the maximum energy in order to reduce the risk of multiple shocks. The MADIT-RIT trial and some observational registries have also recently demonstrated that programming with a widespread use of ATP, higher cut-off rates or delayed intervention reduces the number of inappropriate and unnecessary therapies and improves the survival of patients during mid-term follow-up.

Antiplatelet and antithrombotic treatment for secondary prevention in ischaemic heart disease.

Platelets play a key role in the pathogenesis of acute coronary syndromes and this is why antiplatelet drugs are essential, both in the acute phase and in the long-term follow-up in preventing recurrent myocardial infarction, stroke and cardiovascular death. Aspirin is the most used agent and still remains the first choice drug for lifelong administration in secondary prevention after myocardial infarction. Dual antiplatelet therapy, targeting more than one pathway of platelet activation, has significantly improved the outcome of patients with acute coronary syndromes despite an increased risk of bleeding complications. The aim of this article is to provide an overview of the evidence from randomized clinical trials with a focus on the best association between aspirin and a P2Y12 inhibitor such as clopidogrel, prasugrel or ticagrelor, on the selection of the appropriate agent based on the revascularization strategy and on the optimal duration of such an intensive treatment. We will also provide the latest evidence regarding new antithrombotic agents, such as vorapaxar or low dose rivaroxaban, that could be associated with dual antiplatelet therapy in high risk patients with the aim of further reducing the rate of major ischaemic complications. Finally we will address the issue of patients presenting with atrial fibrillation and a concomitant acute coronary syndrome who frequently need a percutaneous coronary intervention, with a specific focus on the combination therapy of antiplatelet and anticoagulant agents and on the current recommendations of the guidelines.

Ticagrelor therapy and atrioventricular block: Do we need to worry?

Ticagrelor is a potent, direct P2Y12 antagonist with rapid onset of action and intense platelet inhibition, indicated in patients with acute coronary syndromes (ACS). This drug is usually well tolerated, but some patients experience serious adverse effects: Major bleeding; gastrointestinal disturbances; dyspnoea; ventricular pauses > 3 s. Given the unexpected high incidence of bradyarrhythmias, a PLATO substudy monitored this side effect, showing that ticagrelor was associated with an increase in the rate of sinus bradycardia and sinus arrest compared to clopidogrel. This side effect was usually transient, asymptomatic and not associated with higher incidence of severe atrioventricular (AV) block or pacemaker needs. A panel of experts from Food and Drug Administration did not consider bradyarrhythmias a serious problem in clinical practice and, accordingly, current labeling of the drug does not give any precaution or contraindication regarding this issue. However, recently some articles have described ACS patients with high-degree, life-threatening, AV block requiring drug discontinuation and, in some cases, pacemaker implantation. In this paper, we describe and discuss five published case reports of severe AV block following ticagrelor therapy and two other cases managed in our Hospital. The analysis of literature suggests that, although rarely, ticagrelor can be associated with life-threatening AV block. Caution and careful monitoring are required especially in patients with already compromised conduction system and/or treated with AV blocking agents. Future studies, with long-term rhythm monitoring, would help to define the outcome of patients at higher risk of developing this complication.

Externalized conductors and insulation failure in Biotronik defibrillator leads: History repeating or a false alarm?

Conductor externalization and insulation failure are frequent complications with the recalled St. Jude Medical Riata implantable cardioverter-defibrillator (ICD) leads. Conductor externalization is a "unique" failure mechanism: Cables externalize through the insulation ("inside-out" abrasion) and appear outside the lead body. Recently, single reports described a similar failure also for Biotronik leads. Moreover, some studies reported a high rate of electrical dysfunction (not only insulation failure) with Biotronik Linox leads and a reduced survival rate in comparison with the competitors. In this paper we describe the case of a patient with a Biotronik Kentrox ICD lead presenting with signs of insulation failure and conductor externalization at fluoroscopy. Due to the high risk of extraction we decided to implant a new lead, abandoning the damaged one; lead reimplant was uneventful. Subsequently, we review currently available literature about Biotronik Kentrox and Linox ICD lead failure and in particular externalized conductors. Some single-center studies and a non-prospective registry reported a survival rate between 88% and 91% at 5 years for Linox leads, significantly worse than that of other manufacturers. However, the preliminary results of two ongoing multicenter, prospective registries (GALAXY and CELESTIAL) showed 96% survival rate at 5 years after implant, well within industry standards. Ongoing data collection is needed to confirm longer-term performance of this family of ICD leads.