[Sensitivity and specificity of first-level screening in the identification of patients at risk for sudden cardiac death]

Since 1971, in Italy every citizen engaged in competitive sports activity must periodically undergo preventive medical examinations to ascertain eligibility for sports participation. The medical examination includes rest and effort ECG. The Italian model has a very good sensitivity in identifying most pathologies at risk of sudden death particularly in the young (hypertrophic cadiomyopathy, arrhythmogenic right ventricular disease, chanelopathies). In this model, the ECG is very important, being able to disclose cardiac anomalies in most cases. The application of the Italian screening model has progressively reduced the incidence of sudden death in athletes.

[Consensus Statement of Multisocietary Task Force--prescription of physical exercise in the cardiological environment (third part)]

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Recommendations for participation in leisure-time physical activity and competitive sports of patients with arrhythmias and potentially arrhythmogenic conditions. Part II: ventricular arrhythmias, channelopathies and implantable defibrillators

This consensus paper on behalf of the Study Group on Sports Cardiology of the European Society of Cardiology follows a previous one on guidelines for sports participation in competitive and recreational athletes with supraventricular arrhythmias and pacemakers. The question of imminent life-threatening arrhythmias is especially relevant when some form of ventricular rhythm disorder is documented, or when the patient is diagnosed to have inherited a pro-arrhythmogenic disorder. Frequent ventricular premature beats or nonsustained ventricular tachycardia may be a hallmark of underlying pathology and increased risk. Their finding should prompt a thorough cardiac evaluation, including both imaging modalities and electrophysiological techniques. This should allow distinguishing idiopathic rhythm disorders from underlying disease that carries a more ominous prognosis. Recommendations on sports participation in inherited arrhythmogenic conditions and asymptomatic gene carriers are also discussed: congenital and acquired long QT syndrome, short QT syndrome, Brugada syndrome, catecholaminergic polymorphic ventricular tachycardia, arrhythmogenic right ventricular cardiomyopathy and other familial electrical disease of unknown origin. If an implantable cardioverter defibrillator is indicated, it is no substitute for the guidelines relating to the underlying pathology. Moreover, some particular recommendations for patients/athletes with an implantable cardioverter defibrillator are to be observed.

Common atrial flutter and atrial fibrillation are not always two stages of the same disease. A long-term follow-up study in patients with atrial flutter treated with cavo–tricuspid isthmus ablation

OBJECTIVE

Both atrial flutter and atrial fibrillation (AF) frequently develop in the same patient. There is therefore reasonable doubt that flutter ablation may not solve the clinical problem, owing to the occurrence/recurrence of AF. The aim of this study was to establish whether cavo-tricuspid isthmus ablation is curative in patients with common atrial flutter alone or combined with AF.

METHODS

One hundred and forty-one patients (114 male, 27 female, mean age 63 +/- 10 years) who had cavo-tricuspid isthmus ablation were followed up for 44 +/- 20 months. Before ablation, 48 patients had only atrial flutter (group A), whereas 93 patients had both atrial flutter and AF. Among the latter, during antiarrhythmic therapy, 31 patients had only atrial flutter (group B1), whereas 62 patients (group B2) continued to experience both arrhythmias.

RESULTS

During follow-up, 27% of group A and 61% of group B patients had documented recurrent AF (P < 0.001). AF recurred in 51% of group B1 and in 66% of group B2 patients (P = NS). Permanent AF occurred in 6% of group A, 3% of group B1 and 21% of group B2 (P < 0.01). Specific symptom scale scores significantly decreased in all groups, particularly in group A. Two patients of group B had cerebral ischaemic attacks.

CONCLUSIONS

Over a long-term follow-up, cavo-tricuspid isthmus ablation is curative in >70% of patients with atrial flutter alone. Therefore, if no AF is documented, more extensive ablation is not needed. By contrast, cavo-tricuspid isthmus ablation is frequently unable to prevent AF in patients with both atrial flutter and AF, although in some cases a significant clinical benefit may be obtained.

Rationale and design of the GISSI-Atrial Fibrillation Trial: a randomized, prospective, multicentre study on the use of valsartan, an angiotensin II AT1-receptor blocker, in the prevention of atrial fibrillation recurrence

BACKGROUND

The possibility of preventing atrial fibrillation recurrence with anti-arrhythmic agents is very limited, given the discouraging results obtained with current drugs in many patients. Data from experimental studies suggest that angiotensin II AT1-receptor blockers can influence atrial remodelling, a key factor in atrial fibrillation initiation and maintenance. Moreover, some preliminary clinical data show that angiotensin II AT1 -receptor blockers can prevent atrial fibrillation episodes. The GISSI-Atrial Fibrillation (AF) trial is a randomized, prospective, parallel group, placebo-controlled, multicentre study designed to test whether angiotensin II AT1-receptor blockers can reduce atrial fibrillation recurrence.

OBJECTIVES AND METHODS

The primary objective of the study is to demonstrate that, in patients with a history of recent atrial fibrillation who are treated with the best recommended therapies, the addition of the angiotensin II AT1-receptor blocker valsartan (titrated up to 320 mg) is superior to placebo in reducing atrial fibrillation recurrence. A substudy will analyse the effect of valsartan on left atrial dimensions and on neurohormones. The study population consists of patients with symptomatic atrial fibrillation (at least two electrocardiogram documented atrial fibrillation episodes in the previous 6 months or successful cardioversion in the last 2 weeks) with underlying cardiovascular diseases or comorbidities. With approximately 100 centres participating in Italy, a total of 1402 patients are randomized in a 1 : 1 ratio to receive valsartan or placebo. The enrolment period will last 12 months and the patients will be followed for 12 months from study entry.

CONCLUSIONS

The GISSI-AF is the largest trial aimed at assessing the role of angiotensin receptor blockade in reducing the recurrence of atrial fibrillation and its possible mechanisms of action in terms of its effects on atrium remodelling and neurohormones.

Brugada-like electrocardiogram pattern: how to stratify the risk for sudden cardiac death. Is sports activity contraindicated?

Brugada syndrome is associated with a considerable risk of sudden death in young and otherwise healthy adults. The syndrome is estimated to be responsible for at least 4% of all sudden deaths and at least 20% of sudden deaths in patients with structurally normal hearts. The diagnosis of Brugada syndrome is based on peculiar electrocardiogram (ECG) abnormalities classified by the European Society of Cardiology in three types: type 1 (coved-type) is the diagnostic pattern; type 2 (saddle-back type); and type 3 are considered significant if there is a conversion to a type 1, spontaneously or during administration of class I A/C anti-arrhythmic drugs (flecainide, etc.). There is a general agreement about the high risk of sudden death in patients with previous cardiac arrest, for whom an implantable defibrillator (ICD) is recommended. In contrast, controversy exists on the correct clinical behaviour in individuals without a history of previous cardiac arrest. To stratify the risk in patients with type 1 pattern, three major factors have been suggested: typical ECG pattern in the basal state; a history of syncope; and inducible ventricular tachycardia/ventricular fibrillation during electrophysiological study (EPS). However, the indication and usefulness of an EPS is debatable. In patients with a type 2 or 3 pattern a pharmacological test is indicated in the presence of symptoms or of a familial history. With regard to sports eligibility, patients with a history of cardiac arrest should have an ICD and they can practise (low intensity) sport only after the implant of the device. Patients without documented cardiac arrest but at high risk (basal type 1 ECG pattern, syncope and/or positive EPS) should also have an ICD and they can practise (low intensity) sport only after the implant of the device. In patients at low risk (type 1 ECG pattern in the absence of symptoms, without family history and negative EPS) the behaviour regarding sport eligibility is not a matter of debate. In cases with type 2 or 3 pattern, in the absence of familial history and symptoms, a permissive behaviour should be assumed.

DDD versus VVIR versus VVI mode in patients with indication to dual-chamber stimulation: a prospective, randomized, controlled, single-blind study

BACKGROUND

The aim of this study was to compare VVI, VVIR and DDD modes in patients with indication to dual-chamber stimulation, depending on left ventricular function.

METHODS

Two groups of patients were implanted with a DDD pacemaker: Group I with ejection fraction > 40% and Group II with ejection fraction < 40%. Patients with a history of atrial arrhythmia or retrograde conduction were excluded. At follow-up (1 month each) quality of life (QoL), patient preference and echo parameters were collected. At hospital discharge all patients were programmed in DDD for 1 month and then randomized to VVI or VVIR mode. At the end of the period in VVI or VVIR mode each patient underwent a control period in DDD and then was programmed in VVIR or VVI mode.

RESULTS

Seventeen patients out of 23 preferred DDD mode and 6 did not perceive any subjective difference among DDD, VVI and VVIR modes (4/9 in Group I and 2/14 in Group II, p = 0.0017). QoL was significantly different between the two groups and at each follow-up showed the best values in DDD. The correlation between QoL and Tei index was 0.62 in Group I (p < 0.001) and 0.35 in Group II (p = 0.001). Neither ejection fraction nor fractional shortening showed any significant difference during the three phases of the study.

CONCLUSIONS

Most patients preferred the DDD mode. The Tei index showed a good correlation with QoL and both QoL and Tei index significantly improved with DDD mode as compared to VVI and VVIR.

[The problem of sudden death in heart failure]

Sudden death, due to malignant ventricular arrhythmias, is a major problem in heart failure. Mortality increases with NYHA functional class, but the relative percentage due to sudden death is higher in lower NYHA functional classes (50-80% in NYHA class II, 30-50% in NYHA class III, and 5-30% in NYHA class IV). No antiarrhythmic drug is useful to prevent sudden death. In coronary artery disease revascularization reduces mortality in multivessel disease. In all patients with heart failure many drugs are useful in reducing total mortality and sudden death: beta-blockers, angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, antialdosterone drugs, statins, and omega-3 fatty acids. Finally, many prospective randomized studies have demonstrated the efficacy of implantable cardioverter-defibrillators in reducing mortality. However, the high cost-benefit ratio remains an unsolved problem of this therapy.

Pace mapping of Koch's triangle reduces risk of atrioventricular block during ablation of atrioventricular nodal reentrant tachycardia

INTRODUCTION

Slow pathway (SP) ablation of AV nodal reentrant tachycardia (AVNRT) can be complicated by second- to third-degree AV block. We assessed the usefulness of pace mapping of Koch's triangle in preventing this complication.

METHODS AND RESULTS

Nine hundred nine consecutive patients undergoing radiofrequency ablation of AVNRT were analyzed. Group 1 (n=487) underwent conventional slow pathway ablation. Group 2 (n=422) underwent ablation guided by pace mapping of Koch's triangle, which located the anterogradely conducting fast pathway (AFP) based on the shortest St-H interval obtained by stimulating the anteroseptal, midseptal, and posteroseptal aspects of Koch's triangle. In group 2, AFP was anteroseptal in 384 (91%), midseptal in 33 (7.8%), and posteroseptal or absent in 5 (1.2%). In 32 of 33 patients with midseptal AFP, slow pathway ablation was performed strictly in the posteroseptal area. In 4 of 5 patients with posteroseptal or no AFP, retrograde fast pathway was ablated. Two patients refused ablation. Persistent second- to third-degree AV block was induced in 7 (1.4%) of 487 group 1 patients versus 0 (0%) of 422 group 2 patients (P=0.038). Ablation was successful in all patients in whom ablation was performed.

CONCLUSION

Pace mapping of Koch's triangle identifies patients in whom the AFP is absent or is abnormally close to the slow pathway. In these cases, guiding ablation helps to avoid AV block.

Cardiovascular pre-participation screening of young competitive athletes for prevention of sudden death: proposal for a common European protocol. Consensus Statement of the Study Group of Sport Cardiology of the Working Group of Cardiac Rehabilitation and Exercise Physiology and the Working Group of Myocardial and Pericardial Diseases of the European Society of Cardiology

The 1996 American Heart Association consensus panel recommendations stated that pre-participation cardiovascular screening for young competitive athletes is justifiable and compelling on ethical, legal, and medical grounds. The present article represents the consensus statement of the Study Group on Sports Cardiology of the Working Group on Cardiac Rehabilitation and Exercise Physiology and the Working Group on Myocardial and Pericardial diseases of the European Society of Cardiology, which comprises cardiovascular specialists and other physicians from different European countries with extensive clinical experience with young competitive athletes, as well as with pathological substrates of sudden death. The document takes note of the 25-year Italian experience on systematic pre-participation screening of competitive athletes and focuses on relevant issues, mostly regarding the relative risk, causes, and prevalence of sudden death in athletes; the efficacy, feasibility, and cost-effectiveness of population-based pre-participation cardiovascular screening; the key role of 12-lead ECG for identification of cardiovascular diseases such as cardiomyopathies and channelopathies at risk of sudden death during sports; and the potential of preventing fatal events. The main purpose of the consensus document is to reinforce the principle of the need for pre-participation medical clearance of all young athletes involved in organized sports programmes, on the basis of (i) the proven efficacy of systematic screening by 12-lead ECG (in addition to history and physical examination) to identify hypertrophic cardiomyopathy-the leading cause of sports-related sudden death-and to prevent athletic field fatalities; (ii) the potential screening ability in detecting other lethal cardiovascular diseases presenting with ECG abnormalities. The consensus document recommends the implementation of a common European screening protocol essentially based on 12-lead ECG.

Ablation of a single pulmonary vein arrhythmic focus triggering several supraventricular arrhythmias

Pulmonary veins are a well-recognized source of focal ectopies that may trigger atrial fibrillation. Many ablative strategies, in particular ablation of the four pulmonary vein ostia, have been developed in order to cure atrial fibrillation. In some patients, the predominant arrhythmia may be an ectopic atrial tachycardia arising from a pulmonary vein and atrial fibrillation may be only a consequence of rapid atrial activation. There is a paucity of data regarding the electrocardiographic and electrophysiological characteristics of pulmonary vein tachycardia and the ablation strategy of this arrhythmia. In the present paper, we describe a case of a young woman with an arrhythmic focus localized in the right superior pulmonary vein with episodes of atrial tachycardia, paroxysmal atrial fibrillation and atrial flutter, who was successfully treated with transcatheter ablation.