Long-term clinical outcomes of patients with drug-induced type 1 Brugada electrocardiographic pattern: A nationwide cohort registry study

BACKGROUND

There are limited real-world data on the extended prognosis of patients with drug-induced type 1 Brugada electrocardiogram (ECG).

OBJECTIVE

We assessed the clinical outcomes and predictors of life-threatening arrhythmias in patients with drug-induced type 1 Brugada ECG.

METHODS

This multicenter retrospective study, conducted at 21 Italian and Swiss hospitals from July 1997 to May 2021, included consecutive patients with drug-induced type 1 ECG. The primary outcome, a composite of appropriate ICD therapies and sudden cardiac death, was assessed along with the clinical predictors of these events.

RESULTS

A total of 606 patients (mean age 49.7 ± 14.7 years; 423 [69.8%] men) were followed for a median of 60.3 months (interquartile range 23.0-122.4 months). Nineteen patients (3.1%) experienced life-threatening arrhythmias, with a median annual event rate of 0.5% over 5 years and 0.25% over 10 years. The SCN5A mutation was the only predictor of the primary outcome (hazard ratio 4.54; P = .002), whereas a trend was observed for unexplained syncope (hazard ratio 3.85; P = .05). In patients who were asymptomatic at presentation, the median annual rate of life-threatening arrhythmias is 0.24% over 5 years and increases to 1.2% if they have inducible ventricular fibrillation during programmed ventricular stimulation.

CONCLUSION

In patients with drug-induced type 1 Brugada ECG, the annual risk of life-threatening arrhythmias is low, with the SCN5A mutation as the only independent predictor. Unexplained syncope correlated with worse clinical outcomes. Ventricular fibrillation inducibility at programmed ventricular stimulation significantly increases the median annual rate of life-threatening arrhythmias from 0.24% to 1.2% over 5 years.

Opportunities and drawbacks of the subcutaneous defibrillator across different clinical settings

INTRODUCTION

The subcutaneous implantable cardioverter-defibrillator (S-ICD) is an established therapy for the prevention of sudden cardiac death (SCD) and an alternative to a transvenous implantable cardioverter-defibrillator system in selected patients. Beyond randomized clinical trials, many observational studies have described the clinical performance of S-ICD across different subgroups of patients.

AREAS COVERED

Our review aimed to describe the opportunities and drawbacks of the S-ICD, focusing on their use in special populations and across different clinical settings.

EXPERT OPINION

The choice to implant S-ICD should be based on the patient's tailored approach, which takes into account the adequate S-ICD screening at rest or during stress, the infective risk, the ventricular arrhythmia susceptibility, the progressive nature of the underlying disease, the work or sports activity, and the risk of lead-related complications.

Cardiac electrophysiology and pacing educational and training needs among early-career cardiologists: a national survey of the Young Committee of the Italian Association of Arrhythmology and Cardiac Pacing

BACKGROUND

Over the past three decades, cardiac electrophysiology and pacing, including device therapy and catheter ablation of arrhythmias, has rapidly developed as a subspecialty in cardiology. Currently, there is no clear perception about the needs in cardiac electrophysiology and pacing among early-career cardiologists.

METHODS

To address these concerns, the Young Committee of the Italian Association of Arrhythmology and Cardiac Pacing (AIAC) carried out a survey among those under the age of 40 years to obtain detailed information on practical activities and formal lessons during the fellowship in cardiology and their satisfaction and proficiency level at the end of the fellowship.

RESULTS

We obtained 334 answers to the survey. In invasive cardiac electrophysiology and pacing, the percentage of participants attending the activity for a longer time (3-6 months) is lower compared with those in noninvasive subspecialties. About 40% of participants did not receive lessons on interventional cardiology, cardiac electrophysiology and pacing. On the contrary, 71% of participants received an adequate number of lessons on clinical arrhythmology. The vast majority of the participants expressed satisfaction for the education received in the echocardiographic, cardiac interventional laboratories and clinical arrhythmology, but about half of the participants were unsatisfied with the education received in cardiac electrophysiology and pacing. In interventional arrhythmology, the majority of the participants declare their lack of proficiency with two peaks for more complex procedures, namely interventional electrophysiology procedures (82%) and cardiac resynchronization therapy (CRT) procedures (76%).

CONCLUSION

The present survey among Italian early-career cardiologists suggests that the majority of participants consider themselves not confident in performing cardiac electrophysiology and pacing procedures. Due to the complexity of the treatment for heart rhythm disorders and the long learning curve, structured additional training in cardiac electrophysiology and pacing procedures is required after cardiology fellowship.

Electrophysiological Study Prognostic Value and Long-Term Outcome in Drug-Induced Type 1 Brugada Syndrome: The IBRYD Study

OBJECTIVES

This study aimed to retrospectively assess long-term outcome and the prognostic role of electrophysiological study (EPS) for risk stratification of drug-induced type 1 Brugada syndrome (BrS) patients.

BACKGROUND

BrS is a hereditary cardiac disease, predisposing to sudden cardiac death. Few real-world data are available on long-term outcomes of drug-induced type 1 BrS patients, and questions about risk stratification still remain unanswered.

METHODS

The IBRYD (Italian Brugada Syndrome) study is a multicenter observational retrospective study. A total of 226 drug-induced type 1 BrS patients were enrolled from 9 Italian tertiary referral institutions. Primary endpoint was a composite of appropriate implantable cardioverter-defibrillator (ICD) therapy and sudden cardiac death. The authors further assessed clinical predictors to ICD implantation, as well as for arrhythmia induction at EPS, along with EPS as potential risk factor for the outcomes of interest.

RESULTS

142 patients (62.8%) received an ICD due to syncope and/or inducible ventricular tachyarrhythmias at EPS. During a median follow-up of 106 months, 11 patients (4.9%) experienced primary outcome events. The ICD therapy median annual incidence over 8 years was 0.38% (interquartile range: 0% to 1.47%). Ventricular tachyarrhythmia inducibility during EPS was not predictive of arrhythmic events in ICD recipients versus non-ICD patients and in symptomatic versus asymptomatic subgroups, showing a low positive predictive value (9.6% and 8.9%, respectively) versus a high negative predictive value (96.6% and 95%, respectively). The authors reported 29 ICD-related complications and 4.9% inappropriate shocks.

CONCLUSIONS

Drug-induced type 1 BrS patients have a very low arrhythmic risk. Clinical decision for implantation is supported by syncope and/or EPS positivity, though they fail to stratify high-risk patients. A better risk-to-benefit ratio should be pursued, considering both arrhythmic risk and ICD-related complications.

Intensive care and anesthetic management of patients with Brugada syndrome and COVID-19 infection

Coronavirus disease 2019 (COVID-19) spreads across the world, and the intensive care unit (ICU) community must prepare for the challenges associated with this pandemic viral infection. Rapid diagnosis, isolation, and intensive clinical management are very important for all patients with COVID-19, especially for those with cardiac diseases as Brugada syndrome (BrS). BrS is an arrhythmogenic disease reported to be one among the leading causes of sudden cardiac death. In these patients, episodes of lethal arrhythmias may be induced by several factors or situations, and for this reason management during ICU permanence or anesthesia must provide some precautions, avoiding factors that are known to have the potential to worsen the probability to induce arrhythmias. For ICU practitioners, management of acute respiratory failure, hemodynamics, and cardiovascular complications certainly are the key for the best treatment of these patients but to date specific data on supportive ICU care for these patients are lacking, and current recommendations are based on existing evidence from other viral infections and general intensive care management. We want to focus on some general rules, resulted from cases series and clinical practice, to be followed during the ICU management of patients with BrS and concomitant COVID-19 infection.

Link between Brugada phenocopy and myocardial ischemia: Results from the International Registry on Brugada Phenocopy

BACKGROUND

Brugada phenocopies clinical entities that have indistinguishable electrocardiographic (ECG) patterns from true congenital Brugada syndrome. However, they are induced by other clinical circumstances such as myocardial ischemia. The purpose of our study was to examine the clinical features and pathogenesis of ischemia-induced Brugada phenocopy (BrP).

METHODS

Data from 17 cases of ischemia-induced BrP were collected from the International Registry (www.brugadaphenocopy.com). Data were extracted from these publications and authors were contacted to provide further insight into each case.

RESULTS

Of the patients included in this study, 71% were male. Mean age was 59 ± 11 years (range: 38-76). Type-1 Brugada ECG pattern occurred in 15/17 (88%) of the cases, while a type-2 Brugada ECG pattern was observed in the other 2/17 (12%). In all cases, the Brugada ECG pattern resolved upon correction of the ischemia, indicating ischemia as the inducing circumstance. No arrhythmic events have been detected acutely or during the follow-up. Reported time to resolution ranged from 2 minutes to 5 hours. Provocative challenges using sodium channel blocking agents were performed in 7/17 cases (41%), and all failed to induce a Brugada ECG pattern (BrP Class A). The remaining 10/17 cases (59%) did not undergo provocative testing due to various clinical reasons.

CONCLUSIONS

Myocardial ischemia is a commonly reported etiology of BrP. Importantly, this study found no association between BrP induced by myocardial ischemia and sudden cardiac death or malignant ventricular arrhythmias.

Anesthetic and Perioperative Management of Patients With Brugada Syndrome

Brugada syndrome (BrS) is an arrhythmogenic disease reported to be one among the leading causes of cardiac death in subjects under the age of 40 years. In these patients, episodes of lethal arrhythmias may be induced by several factors or situations, and for this reason, management during anesthesia and surgery must provide some precautions and drugs restrictions. To date, it is difficult to formulate guidelines for anesthetic management of patients with BrS because of the absence of prospective studies, and there is not a definite recommendation for neither general nor regional anesthesia, and there are no large studies in merit. For this reason, in the anesthesia management of patients with BrS, the decision of using each drug must be made after careful consideration and always in controlled conditions, avoiding other factors that are known to have the potential to induce arrhythmias and with a close cooperation between anesthetists and cardiologists, which is essential before and after surgery. In conclusion, given the absence of large studies in literature, we want to focus on some general rules, which resulted from case series and clinical practice, to be followed during the perioperative and anesthetic management of patients with BrS.

Recurrent in-stent restenosis, certainty of its origin, uncertainty about treatment

Treatment of recurrent in-stent restenosis is a real brainteaser for the interventional cardiologist who cannot resort to the guidelines to have indications about the type of treatment to be preferred. The use of intracoronary imaging may provide insights into the underlying mechanisms of this complication and use of drug-coated balloons may be a valid alternative and especially a thoughtful treatment when the repeated and perseverant use of drug-eluting stents clearly fails. In this setting, we present a review of the literature about this interesting topic, going deep into the heart of the problem, its origin and possible treatment options.

Pathogenesis and management of Brugada syndrome

Brugada syndrome is an inherited disease characterized by an increased risk of sudden cardiac death owing to ventricular arrhythmias in the absence of structural heart disease. Since the first description of the syndrome >20 years ago, considerable advances have been made in our understanding of the underlying mechanisms involved and the strategies to stratify at-risk patients. The development of repolarization-depolarization abnormalities in patients with Brugada syndrome can involve genetic alterations, abnormal neural crest cell migration, improper gap junctional communication, or connexome abnormalities. A common phenotype observed on the electrocardiogram of patients with Brugada syndrome might be the result of different pathophysiological mechanisms. Furthermore, risk stratification of this patient cohort is critical, and although some risk factors for Brugada syndrome have been frequently reported, several others remain unconfirmed. Current clinical guidelines offer recommendations for patients at high risk of developing sudden cardiac death, but the management of those at low risk has not yet been defined. In this Review, we discuss the proposed mechanisms that underlie the development of Brugada syndrome and the current risk stratification and therapeutic options available for these patients.

Relationship between coronary artery ectasia, cocaine abuse and acute coronary syndromes

Coronary artery ectasia (CAE) often represents a coronary angiography finding casually detected or following the occurrence of an acute coronary syndrome. The pathogenetic role of cocaine abuse in the genesis of CAE is still little known and very few data are available in literature. We describe a case of a 31-year-old male cocaine user admitted to our department for typical acute chest pain. Coronary angiography showed diffuse coronary ectasia with slow flows and without hemodynamically significant stenosis. An increasing of matrix metalloproteinases values and a reduction of their tissue inhibitors was showed both during hospitalization and at one month after discharge. This case report emphasizes the close relationship between cocaine abuse, CAE and acute coronary syndromes in patients without hemodynamically significant coronary stenosis. As reported by Satran et al, cocaine abuse should be considered an important risk factor for CAE and these patients appear to be at increased risk of angina and acute myocardial infarct. Further studies that can strengthen this hypothesis would be useful to deepen and better analyze this interesting association.

Brugada syndrome and Brugada phenocopy. The importance of a differential diagnosis

To date Brugada syndrome (BrS) is considered a primary electrical heart disease and the diagnosis is based on precise clinical and electrocardiographic features. Many other diseases and conditions can lead to a Brugada-like ECG pattern but the vast majority of patients with BrS possess a structurally normal heart, which is consistent with the notion that this is a primary electrical heart disease. Presently, the terminology used in the literature to describe Brugada type 1 ECG pattern induced in patients without BrS is diverse and variable. Brugada phenocopies (BrP) are clinical entities that present with identical ECG patterns to those of true BrS but are elicited by various other clinical circumstances. They form a group of heterogeneous conditions that are perhaps the most difficult to differentiate from true congenital BrS due to identical ECG patterns and recently has been proposed an updated classification of conditions that may induce BrP and many criteria useful to differentiate BrP from BrS. A systematic diagnostic approach is crucial to avoid diagnostic errors that involve expenditure of time and resources, but above all it is useful to avoid to send patients without a real BrS to inopportune diagnostic and therapeutic paths that are sometimes burdened by considerable risks.

In-stent Restenosis: COMBO Stent May Guarantee a Proper Healing

<p>The risk of ISR appears to be related to several factors which cooperate synergistically; among these factors an important role is played by: the metal struts of the stent and the consequent inflammatory stress on the vascular wall which favors an excessive neointimal proliferation that "attacking" the stent struts, progressively and critically reduce the vessel lumen.<br />Drug eluting balloon is the gold standard in this setting due to the absence of metallic struts. COMBO stent could be a viable alternative which may properly compare to DEB in the ISR treatment: one of a kind, because it has a dual therapy action, synergistically combining the effect of sirolimus with the presence of CD34+ antibodies on the surface of its struts, capturing circulating endothelial progenitor cells (EPCs), so mobilized EPCs differentiate into functional endothelium and allowing a homogeneous neointimal formation.<br /> Here we are presenting an intriguing case of a ISR treated successfully with COMBO and confirmed by 5-months angiographic and IVUS follow-up. </p>

Coronary Artery Fistulas: Symptoms may not Correlate to Size. An Emblematic Case and Literature Review

<p>Coronary artery fistulas are rare anatomic abnormalities of the coronary arteries present in 0.002% of the general population and represent 14% of all anomalies of coronary arteries. Their clinical relevance focuses mainly on the mechanism of "coronary steal phenomenon”, causing myocardial functional ischemia even in the absence of stenosis, hence common symptoms are angina or dyspnea. Small size fistulas are mostly asymptomatic and have excellent prognosis if managed medically with regular follow-up consisting also in echocardiography every 2-5 years. Big-sized and symptomatic fistulas, on the contrary, should undergo invasive closure, either with a transcatheter approach or with surgical ligation, whose results are equivalent at long-term follow-up. However, in some cases, symptoms may not correspond with size. Larger fistulas may be asymptomatic and very small fistulas may cause symptoms like angina in our patient. Here, we are presenting an emblematic and very rare case with a complete literature review. Particularly, very didactic angiography images and then during surgery are shown. </p>

Coronary artery fistulas as a cause of angina: How to manage these patients?

Coronary artery fistulas represent the most common hemodynamically significant congenital defect of the coronary arteries and the clinical presentation is mainly dependent on the severity of the left-to-right shunt. We describe a case of a 55-year-old man with history of chest pain and without history of previous significant chest wall trauma or any invasive cardiac procedures. A coronary multislice computed tomography showed two large coronary fistulas arising from the left anterior descending coronary artery and ending in an angiomatous plexus draining into the common pulmonary trunk. Coronary angiography confirmed the CT finding and showed a third fistulous communication arising from the sinus node artery. Although coronary fistulas are infrequent, they are becoming increasingly important because their management and treatment could prevent serious complications. The latest guidelines of the American College of Cardiology/American Heart Association indicate as Class I recommendation the percutaneous or surgical closure for large fistulas regardless of symptoms. In this manuscript, we provide a detailed review of the literature on this topic, focusing on the clinical management of these patients.

[Coronary artery ectasia: etiopathogenesis, diagnosis and treatment]

Coronary ectasia is a dilation of coronary arteries, angiographically defined if the diameter of the artery is ≥ 1.5 times greater than that of the intact adjacent vascular segment. An association has been found between coronary artery ectasia and a broad spectrum of different diseases, first of all atherosclerotic coronary artery disease. The mechanisms that determine the abnormal dilatation of the vascular lumen and the etiology of coronary artery ectasia are still poorly understood. Various hypotheses have been formulated over the time, the most accredited between these recognizes as main responsible an uncontrolled activity of a particular family of enzymes that degrade the extracellular matrix, the metalloproteinases. This exaggerated activity can be due to an increase in the absolute sense of these enzymes and/or a reduction in the levels of their natural specific inhibitors. Coronary ectasia may have a variable clinical presentation. It is often an occasional finding detected at coronary angiography or following the occurrence of atypical chest pain, stable angina or even acute coronary syndrome. The frequent coexistence of coronary artery ectasia and atherosclerotic coronary artery disease and their common histopathological features have led to hypothesize that coronary ectasia may represent a variant of atherosclerosis. However, some significant differences between these two diseases leave open the hypothesis that coronary artery ectasia may be a pathological entity per se.

[Interindividual differences in the response to statin therapy and gene polymorphisms related to myopathy during statin therapy]

The enzyme HMG-CoA reductase (HMGCR), the main site of action of statins, undergoes alternative splicing of exon 13, which encodes the binding domain of statins to the enzyme. The resulting isoform, called HMGCRv1, shows altered enzyme activity and sensitivity to statins compared to the classical isoform. This translates into interindividual differences in the response to treatment with these drugs. A recent discovery in the field of genetics has brought about the identification of the single nucleotide polymorphism rs4363657 of the SLCO1B1 gene located on chromosome 12. This polymorphism is strongly associated with myopathy induced by statins. From the available literature, a clinical study has evaluated the relationship between gene polymorphisms and myopathy during statin therapy. The study involved 12 000 patients treated with simvastatin at a dose of 80 mg/day. The odds ratio for myopathy was 4.5 (95% confidence interval 2.6-7.7) per copy of the C allele, and 16.9 (95% confidence interval 4.7-61.1) in CC as compared with TT homozygotes. Myopathy could be attributed to the C variant in more than 60% of cases. Genomic typing may allow the identification of these variants, leading to a tailored statin therapy with higher benefits to the patients and less adverse side effects.