Prevalence and clinical significance of isolated low QRS voltages in young athletes.

AIMS: Low QRS voltages (peak to peak <0.5 mV) in limb leads (LQRSV) on the athlete's electrocardiogram (ECG) may reflect an underlying cardiomyopathy, mostly arrhythmogenic cardiomyopathy (ACM) or non-ischaemic left ventricular scar (NILVS). We studied the prevalence and clinical meaning of isolated LQRSV in a large cohort of competitive athletes. METHODS AND RESULTS: The index group included 2229 Italian competitive athletes [median age 18 years (16-25), 67% males, 97% Caucasian] without major ECG abnormalities at pre-participation screening. Three control groups included Black athletes (N = 1115), general population (N = 1115), and patients with ACM or NILVS (N = 58). Echocardiogram was performed in all athletes with isolated LQRSV and cardiac magnetic resonance (CMR) in those with ventricular arrhythmias or echocardiographic abnormalities. The isolated LQRSV pattern was found in 1.1% index athletes and was associated with increasing age (median age 28 vs. 18 years; P < 0.001), elite status (71% vs. 34%; P < 0.001), body surface area, and body mass index but not with sex, type of sport, and echocardiographic left ventricular mass. The prevalence of isolated LQRSV was 0.2% in Black athletes and 0.3% in young individuals from the general population. Cardiomyopathy patients had a significantly greater prevalence of isolated LQRSV (12%) than index athletes, Black athletes, and general population. Five index athletes with isolated LQSRV and exercise-induced ventricular arrhythmias underwent CMR showing biventricular ACM in 1 and idiopathic NILVS in 1. CONCLUSIONS: Unlike cardiomyopathy patients, the ECG pattern of isolated LQRSV was rarely observed in athletes. This ECG sign should prompt clinical work-up for exclusion of an underlying cardiomyopathy.

Choosing wisely in cardiology: Five proposals from the Italian Association for Cardiovascular Prevention and Rehabilitation.

We do not always accomplish what is best for our patients. Is "more procedures, more drugs" a real synonym of good and always useful medicine? Probably not. Indeed, it has been highlighted that many tests and treatments, widely used in medical practice, do not bring benefits to patients, but they can be harmful. So, why do we keep performing them? Many reasons, surely one of the main is the constant fear of malpractice legal-medical consequences; this led to the development of a defensive medicine, no longer focused on the health of the patient. For this reason, the Italian Association of Cardiac Prevention and Rehabilitation (GICR-IACPR) joined an international project "Choosing Wisely", supported by the Slow Medicine Initiative, a network which states that "Less is more". The purpose of "Choosing Wisely " project is to improve the quality and safety of health services through the reduction of practices that, according to available scientific knowledge, do not bring significant benefits to the patients, but can, on the contrary, expose them to risks. This GICR-IACPR paper proposes to avoid five widespread practices in cardiology, at risk for inappropriateness and lacking of clinical evidence of benefit: • Do not perform routine chest X-ray in patients entering rehabilitation programme after cardiac surgery • Do not perform Computed Tomography for coronary calcium score in patients at high cardiovascular risk • Do not perform Holter electrocardiographic monitoring in patients suffering from syncope, near syncope or dizziness, in whom a non-arrhythmic origin has been documented • Do not routinely prescribe proton pump inhibitors (PPI) for gastrointestinal bleeding prophylaxis in patient with single drug antiplatelet therapy in absence of additional risk factors. • Avoid routine use of infective endocarditis prophylaxis in mild to moderate native valve disease.

Exercise-based cardiac rehabilitation in cardiac resynchronization therapy recipients: A primer for practicing clinicians.

Cardiac resynchronization therapy (CRT) is a therapeutic option of increasing importance for chronic heart failure (CHF) and criteria for implantation now concern a large amount of patient populations. As a consequence, subjects with ongoing CRT (or immediately after CRT implantation) are more often referred to Cardiac Rehabilitation (CR) programmes, and it has been recently estimated that about one third of CHF patients attending CR in Italy currently have this kind of device. The presence of CRT represents a modulating factor for exercise prescription and monitoring, since CRT patients may be considered per se as a target group for CR. Exercise therapy (ET) increases benefits from CRT on functional capacity, and recent evidence suggests an adjuvant role of ET in improving cardiovascular prognosis also. Both aerobic endurance and resistance training activities may involve CHF patients with CRT, while the potential role of aerobic interval training needs more studies and evidence. Prescription of an ET program should be associated with information regarding device programming and possible limiting factors associated with pacing therapy, tailoring of the basic principles of ET (in terms of type of exercise, intensity and program duration) in this patient group is mandatory.

Prevalence and determinants of low QRS voltages and QRS fragmentation in children and adolescents undergoing sports preparticipation screening.

AIMS: Low QRS Voltages (LQRSV) in limb leads and QRS fragmentation (FQRS) are possible electrocardiographic signs of myocardial fibrosis and cardiomyopathy, but they are not listed in current criteria for interpretating athlete's ECG. We investigated the prevalence and determinants of LQRSV and FQRS in a cohort of young apparently healthy athletes undergoing preparticipation screening (PPS). METHODS: We analysed a consecutive series of 2140 ECG obtained during PPS of young athletes (mean age 12.5±2.6 years, 7-18 year-old, 49% males). The peak-to-peak QRS voltage was measured in all limb leads and LQRSV were defined when maximum value was <0.5 mV. Fragmented QRS morphologies were grouped into five patterns. Lead aVR was not considered. RESULTS: Maximum peak-to-peak QRS voltage in limb leads was 1.4±0.4 mV, similar between younger and older athletes, but significantly lower in females than males (1.35±0.38mV vs 1.45±0.42mV; p<0.001). There was a weak correlation between maximal QRS voltages and body mass index (BMI), but not with type of sport or training load. Only 5 (0.2%) individuals showed LQRSV. At least one fragmented QRS complex was identified in 831 (39%) individuals but excluding the rSr' pattern in V1-V2, only 10 (0.5%) showed FQRS in ≥2 contiguous leads. They were older than those without FQRS, but did not differ in terms of gender, BMI, type of sport or training load. CONCLUSIONS: LQRSV in limb leads and FQRSV in ≥2 contiguous leads excluding V1-V2 are rare in young apparently healthy athletes and are not related to the type and intensity of sport activity. Therefore, they may require additional testing to rule out an underlying disease particularly when other abnormalities are present.

Low QRS Voltages (LQRSV) in limb leads and QRS fragmentation (FQRS) are possible electrocardiographic signs of myocardial fibrosis and cardiomyopathy. In our study, we analyzed the occurrence and characteristics of FQRS and LQRSV in young athletes undergoing preparticipation screening. We found a low prevalence of these abnormalities, with only 0.2% showing LQRSV and 0.5% displaying FQRS. These abnormalities were not associated with factors such as gender, age, type of sport, or training load.

Current and emerging indications for implantable cardiac monitors.

Implantable cardiac monitors (ICMs) continuously monitor the patient's electrocardiogram and perform real-time analysis of the heart rhythm, for up to 36 months. The current clinical use of ICMs involves the evaluation of transitory symptoms of possible arrhythmic origin, such as unexplained syncope and palpitations. Moreover, ICMs can also be used for the evaluation of difficult cases of epilepsy and unexplained falls, though current indications for their application in these sectors are less clearly defined. Finally, the ability of new-generation ICMs to automatically record arrhythmic episodes suggests that these devices could also be used to study asymptomatic arrhythmias, and thus could be proposed for the long-term evaluation of the total (symptomatic and asymptomatic) arrhythmic burden in patients at risk of arrhythmic events. In particular, ICMs may have an emerging role in the management of patients with atrial fibrillation and in those at risk of ventricular arrhythmias.

Acceptability and Practicality of a Quick Musculoskeletal Examination into Sports Medicine Pre-Participation Evaluation.

BACKGROUND: Child musculoskeletal (MSK) diseases are common and, even if often benign, sometimes can lead to significant impairment in the future health of children. Italian pre-participation evaluation (PPE), performed by a sports medicine physician, allows for the screening of a wide range of children every year. Therefore, this study aims to evaluate the feasibility and the acceptability of pGALS (pediatric Gait, Arms, Legs and Spine) screening, a simple pediatric MSK screening examination, when performed as part of a routine PPE. METHODS: Consecutive school-aged children attending a sports medicine screening program were assessed with the addition of pGALS to the routine clinical examination. Practicability (time taken) and patient acceptability (discomfort caused) were recorded. RESULTS: 654 children (326 male, mean age 8.9 years) were evaluated through pGALS. The average time taken was 4.26 min (range 1.9-7.3 min). Acceptability of pGALS was deemed high: time taken was "adequate" (97% of parents) and caused little or no discomfort (94% of children). Abnormal MSK findings were common. CONCLUSIONS: pGALS is a practical and acceptable tool to perform in sports medicine PPE, even if performed by a non-expert in MSK medicine. Although common, abnormal MSK findings need to be interpreted in the global clinical context and assessment.

Physical and psychological reconditioning in long COVID syndrome: Results of an out-of-hospital exercise and psychological - based rehabilitation program.

Background: Long Covid Syndrome (LCS) is used to describe signs and symptoms that continue or develop after acute COVID-19 infection. Natural history and treatment of this syndrome are still poorly understood, even if evidences suggest the potential role of physical rehabilitation in improving symptoms in these patients. Aim of the study: The aim of the present study was to evaluate effectiveness, safety and feasibility of an out-of-hospital multidisciplinary rehabilitation (MDR) program, based both on physical and psychological reconditioning, in reducing symptoms and improving physical fitness and psychological parameters in patients with LCS. Methods: Thirty consecutive patients with LCS (18 males, mean age 58 years) underwent an accurate medical screening process including anthropometric and muscular strength evaluation, cardiopulmonary exercise test, quality of life (QoL) and psychological appraisal before and after a MDR program. Results: At baseline, all LCS patients were strongly symptomatic and showed severe impairments in physical performance, QoL and psychological parameters. No adverse effects and dropouts were observed during the exercise training sessions. After the MDR program, COVID-19 residual symptoms significantly decreased, and significant improvements in upper and lower limb muscular strength, cardiopulmonary parameters, perceived physical and mental health, depression and anxiety were observed. Conclusions: The present study confirms the severe physical and psychological impairment of patients with LCS and suggests that a MDR program is effective, safe and feasible in these patients and could promote their physical and psychological recovery.

Safety of surgical masks during physical activity evaluated with graded cycle ergometry test.

BACKGROUND: At the time of the coronavirus disease 2019 (COVID-19) pandemic wearing surgical mask (SM) is recommended for the prevention of contracting or exposing others to airborne transmission of COVID-19. It is somewhat controversial whether wearing SM during exercise affects performance and health status and/or may influence the results. In order to give an answer we planned a prospective, randomized, crossover study to evaluate the effects of wearing a SM or no-SM in 33 (17 male) physically active healthy subjects during a graded exercise cycle ergometry test. METHODS: The two tests were performed in random order in the same subjects. The participants were all tested the same day, after a recovery time of at least of one hour, in order to avoid interferences on physical performances. Arterial oxygen saturation, heart rate and arterial blood pressure were assessed throughout the exercise tests every step of two minutes, at the end of exercise, performed at the same time with and without mask. RESULTS: Wearing SM had no effect on performance, since the duration of cycle ergometry test with SM and without SM median, respectively, was 14.2 (lower-upper quartile 13.9-14.8) versus 14.3 (13.9-15.5) minutes (P=0.094), and median peak power was 150 W (150-180) versus 150 W (120-180) (P=0.754). CONCLUSIONS: When expressed relative to peak exercise performance, no differences were found between wearing or not wearing SM regarding arterial oxygen saturation, or heart rate at any time during the exercise tests. Wearing SM during vigorous exercise had no detrimental effect on cardiovascular parameters, as well as on exercise metrics in all participants. No ventricular repolarization abnormalities and no arrhythmias were reported on the electrocardiograms.

Effectiveness of remote monitoring in the management of syncope and palpitations.

AIMS: Recently, the remote transmission of data detected by implantable loop recorders (ILRs) has become available. The aim of this study was to evaluate effectiveness and acceptance of remote monitoring in the clinical management of syncope and palpitations in patients with ILR. METHODS AND RESULTS: Consecutive patients implanted with ILR (Reveal DX/XT Medtronic, Inc.) and followed up by means of remote monitoring (CareLink(®)) were included. The patients were requested to transmit the data stored in the ILR every week, via the CareLink system, or more frequently during the first period. Patient acceptance of ILR was evaluated by means of a questionnaire concerning physical and mental components. Forty-seven patients (27 males, average age 64 ± 19 years) were enrolled and followed up for 20 ± 13 weeks. Thirty-two patients (68%) had at least one ECG recording of a true relevant event. The mean time from ILR implantation to the first true relevant ECG was 28 ± 49 days, which was 71 ± 17 days less than in the clinical practice of 3-monthly in-office follow-up examinations. Thirty-eight patients (81%) had at least one false arrhythmic event, mainly false asystole and false fast ventricular tachycardia. In the absence of Carelink transmission, at least one episode of memory saturation of ILR would have occurred in 21 patients (45%) that would have limited the diagnostic yield. Patient compliance was good even though one-fifth had some minor psychological concern regarding the ILR implant. CareLink was well accepted and judged easy to use. CONCLUSION: Remote monitoring enhances the diagnostic effectiveness of Reveal, limiting the risk of memory saturation due to the high number of false detections and reducing the time to diagnosis. Both ILR and CareLink were well accepted and well tolerated by the patients, as they were considered useful.

Early and late outcome of treated patients referred for syncope to emergency department: the EGSYS 2 follow-up study.

AIMS: We evaluated the early (1 month) and late (2 years) death rate and syncopal relapses of patients referred for syncope to 11 general hospitals emergency departments. Patients were enrolled in the Evaluation of Guidelines in SYncope Study 2 (EGSYS 2) study. The guidelines of the European Society of Cardiology were strictly followed in the management of patients. METHODS AND RESULTS: Out of the 465 patients enrolled in the EGSYS 2 study, 398 (86%) underwent a complete follow-up. We excluded 18 patients with non-syncopal attacks. Among the remaining 380 patients, death of any cause occurred in 35 (9.2%). The mean follow-up was 614 +/- 73 days. Six deaths (17% of total) occurred during the first month of follow-up. Patients who died were older, had a higher incidence of structural heart disease and/or abnormal ECG, had injuries related to syncope and higher EGSYS score. Syncope recurred in 63 (16.5%) patients. Syncopal relapses occurred in only one patient during the first month of follow-up. The incidence of syncopal recurrences was unrelated to the mechanism of syncope. No clinical differences were found between patients with or without syncopal recurrence and in patients with EGSYS score < or >or=3. CONCLUSION: A peak of cardiovascular mortality but not of syncopal recurrences was observed in patients attending to the emergency department for syncope within the first month. Late unfavourable outcomes were caused by associated cardiovascular diseases rather than by the mechanism of syncope. The causes of syncope did not determine the recurrence rate.

Italian Cardiological Guidelines (COCIS) for Competitive Sport Eligibility in athletes with heart disease: update 2020.

Since 1989, SIC Sport and a FMSI, in partnership with leading Italian Cardiological Scientific Associations (ANCE, ANMCO and SIC) have produced Cardiological Guidelines for Completive Sports Eligibility for athletes with heart disease (COCIS -- 1989, 1995, 2003, 2009 and 2017). The English version of the Italian Cardiological Guidelines for Competitive Sports Eligibility for athletes with heart disease was published in 2013 in this Journal. This publication is an update with respect to the document previously published in English in 2013. It includes the principal innovations that have emerged over recent years, and is divided into five main chapters: arrhythmias, ion channel disorders, congenital heart diseases, acquired valve diseases, cardiomyopathies, myocarditis and pericarditis and ischemic heart disease. Wherever no new data have been introduced with respect to the 2013 publication, please refer to the previous version. This document is intended to complement recent European and American guidelines but an important difference should be noted. The European and American guidelines indicate good practice for people engaging in physical activity at various levels, not only at the competitive level. In contrast, the COCIS guidelines refer specifically to competitive athletes in various sports including those with high cardiovascular stress. This explains why Italian guidelines are more restrictive than European and USA ones. COCIS guidelines address 'sports doctors' who, in Italy, must certify fitness to participate in competitive sports. In Italy, this certificate is essential for participating in any competition.

Sports and arrhythmias: a report of the International Workshop Venice Arrhythmias 2009.

This article is a report of an international symposium, endorsed by the Section on Sports Cardiology of the European Association for Cardiovascular Prevention and Rehabilitation, the Italian Society of Sports Cardiology, and the Italian Federation of Sports Medicine, which was held within the 11th International Workshop on Cardiac Arrhythmias (Venice Arrhythmias 2009, Venice, Italy, October 2009). The following main topics were discussed during the symposium: the role of novel diagnostic examinations to assess the risk of sudden death in athletes, controversies on arrhythmic risk evaluation in athletes, controversies on the relationship between sports and arrhythmias, and controversies on antiarrhythmic treatment in athletes.

Prospective multicentre systematic guideline-based management of patients referred to the Syncope Units of general hospitals.

AIMS: Although an organizational model for syncope management facilities was proposed in the 2004 guidelines of the European Society of Cardiology (ESC), its implementation in clinical practice and its effectiveness are largely unknown. METHODS AND RESULTS: This prospective study enrolled 941 consecutive patients referred to the Syncope Units of nine general hospitals from 15 March 2008 to 15 September 2008. A median of 15 patients per month were examined in each unit, but the five older units had a two-fold higher volume of activity than the four newer ones (instituted <1 year before): 23 vs. 12, P = 0.02. These figures give an estimated volume of 163 and 60 patients per 100,000 inhabitants per year, respectively. Referrals: 60% from out-of-hospital services, 11% immediate and 13% delayed referrals from the Emergency Department, and 16% hospitalized patients. A diagnosis was established on initial evaluation in 191 (21%) patients and early by means of 2.9 +/- 1.6 tests in 541 (61%) patients. A likely reflex cause was established in 67%, orthostatic hypotension in 4%, cardiac in 6% and non-syncopal in 5% of the cases. The cause of syncope remained unexplained in 159 (18%) patients, despite a mean of 3.5 +/- 1.8 tests per patient. These latter patients were older, more frequently had structural heart disease or electrocardiographic abnormalities, unpredictable onset of syncope due to the lack of prodromes, and higher OESIL and EGSIS risk scores than the other groups of patients. The mean costs of diagnostic evaluation was 209 euro per outpatient and 1073 euro per inpatient. The median cost of hospital stay was 2990 euro per patient. CONCLUSION: We documented the current practice of syncope management in specialized facilities that have adopted the management model proposed by the ESC. The results are useful for those who wish to replicate this model in other hospitals. Syncope remains unexplained during in-hospital evaluation in more complex cases at higher risk.

Clinical Approach to Patients with Palpitations.

Palpitations are among the most common symptoms that prompt patients to consult a physician. In the diagnostic workup of patients with palpitations, the initial evaluation involves history, physical examination, and 12-lead electrocardiogram. These investigations yield a prognostic stratification of the patients, and a definitive suspected diagnosis of the cause of symptoms in a good proportion of cases. When the initial evaluation results are negative and the patient is suffering from heart disease, or if the palpitations are frequent or poorly tolerated and with a high probability of an arrhythmic origin, ambulatory electrocardiogram monitoring and/or electrophysiological study should be undertaken.

[Consensus document and recommendations for the prevention of cardiovascular disease in Italy - 2018]. / Documento di consenso e raccomandazioni per la prevenzione cardiovascolare in Italia 2018.

Cardiovascular prevention represents a cornerstone of modern strategies to reduce the burden of cardiovascular disease. It is of key importance to prevent cardiovascular diseases and associated events, not only to reduce morbidity and mortality, but also to increase the years of wellness in the aging population and to make the growing socio-economic burden imposed by cardiovascular events more sustainable.The current approach to prevention is based on an integrated use of effective lifestyle measures and, whenever appropriate, of antihypertensive and antidiabetic drugs, lipid-lowering agents and antiplatelet drugs.Given that population characteristics, in terms of ethnicity, demography and lifestyle habits, and healthcare system organizations differ among countries, international guidelines are not always applicable to specific countries and, often, are difficult to translate into daily clinical practice.In order to afford the specific features of Italy, 10 Scientific Societies and Research Institutions, mostly involved in preventive strategies, contributed to the present Italian consensus document, which includes brief, practical recommendations to support the preventive actions within the physician community and the general practice setting.

Value of Ambulatory Electrocardiographic Monitoring in Syncope.

Implantable loop recorders (ILRs) continuously monitor electrocardiographic signals and perform real-time analysis of heart rhythm for up to 36 months. ILRs are used to evaluate transitory loss of consciousness from possible arrhythmic origin, particularly unexplained syncope, and to evaluate difficult cases of epilepsy and unexplained falls, although current indications for their application in these areas are less clearly defined. This article analyzes the current indications for ILRs according the European Society of Cardiology guidelines on the management of syncope and the European Heart Rhythm Association guidelines on the use of implantable and external electrocardiogram loop recorders, and their limitations.

Diagnostic management of patients with palpitations of unknown origin.

The first-line investigations in the diagnostic management of patients with palpitations include history taking, physical examination and ECG. These investigations yield a definitive or probable diagnosis in a good proportion of patients. If the patient is suffering from heart disease, or if the palpitations are frequent or poorly tolerated, ambulatory ECG monitoring and electrophysiological study should be undertaken. Holter monitoring (useful when symptoms occur daily) has a rather low sensitivity, while event recorders (useful in compliant patients with infrequent palpitations that are fairly long-lasting) and external loop recorders (recommended in cases of infrequent short-lasting palpitations associated with hemodynamic impairment) have proved to have a higher sensitivity. The diagnostic yield of the electrophysiological study (generally recommended when the recording attempts using ambulatory ECG monitoring fail to provide a diagnosis) depends on the stimulation protocol used, the clinical characteristics of the patients studied, and the type of arrhythmias induced. Implantable loop recorders may be recommended in patients with rare, highly symptomatic palpitations associated or not with hemodynamic impairment, when the other diagnostic modalities prove to be inconclusive.

[How is syncope studied in the Italian hospitals?]. / Come viene studiata la sincope negli ospedali italiani? Risultati del primo "Censimento Nazionale dei Centri per lo studio della sincope".

BACKGROUND: The aim of this study was to evaluate how the main tests for the diagnostic assessment of syncope are currently performed in the Italian hospitals. METHODS: During the early 2003 dedicated questionnaires were administered to about 400 Italian hospitals. About each test information was requested relative to: test protocol, laboratory equipment, patients evaluated during 2002. RESULTS: Eighty-four hospitals answered the questionnaire. A syncope-dedicated ambulatory (at least once a week) was available during 2002 in 59/84 hospitals, and 56 were dependent on the Cardiology Division. Carotid sinus massage was performed either in clinostatic and in orthostatic position in 60 Centers and was repeated after atropine in 15. To define the test positivity, 35 Centers followed the "symptom method". Only 15 Centers performed > 100 procedures during 2002 (range 3-500). Tilt testing was performed in 72 hospitals. A dedicated tilting bed was available in 65 Centers, continuous beat-to-beat pressure measurement in 22. Out of the 72 Centers, 55 followed the so-called "Italian protocol" as the main methodology of the test. Only 17 Centers performed > 100 procedures during 2002 (range 3-500). Adenosine test was performed in 26 hospitals, the median dose of drug was 18 mg (range 6-20 mg); 25 out 26 Centers considered the test as positive when an asystolic pause > or = 6 s was observed. Only 6 Centers performed > 15 procedures during 2002 (range 1-204). An implantable loop recorder was available in 48 Centers. The number of implant procedures during 2002 varied among the Centers from 1 to 22. CONCLUSIONS: A great variability was observed concerning the methodology of each test and the number of procedures performed. Thus, a standardization effort about the methodology of syncope study is still needed by the medical associations.

Prevention of syncope through permanent cardiac pacing in patients with bifascicular block and syncope of unexplained origin: the PRESS study.

BACKGROUND: Syncope in patients with bifascicular block (BFB) is a common event whose causes might be difficult to assess. METHODS AND RESULTS: Prevention of syncope through permanent cardiac pacing in patients with bifascicular block (PRESS) is a multicenter, prospective, randomized, single-blinded study designed to demonstrate a reduction in symptomatic events in patients with bifascicular block and syncope of undetermined origin implanted with permanent pacemaker. Device programming mode (NASPE/BPEG code) at DDD with a lower rate of 60 ppm is compared with backup pacing at DDI with a lower rate of 30 ppm. The end point consisted of (1) syncope, (2) symptomatic presyncopal episodes associated with a device intervention (ventricular pacing), and (3) symptomatic episodes associated with intermittent or permanent atrioventricular block (any degree). One hundred one patients were enrolled and randomized. Primary end point events at 2 years were observed in 23 patients, with a significant lower incidence in the study group (hazard ratio, 0.32; 95% confidence interval [CI], 0.10-0.96; P=0.042). Reduction of any symptoms, associated or not with device intervention, was superior in DDD60 compared with DDI30 (hazard ratio, 0.4; 95% confidence interval, 0.25-0.78; P=0.0053). Fourteen patients developed other rhythm diseases and met class I indication for pacing. The annual incidence of rhythm disease development was 7.4%. CONCLUSIONS: In patients with bifascicular block and syncope of undetermined origin, the use of a dual chamber pacemaker programmed to DDD60 led to a significant reduction of syncope or symptomatic events associated with a cardioinhibitory origin, compared with DDI30 programming. Symptoms associated with a new onset of rhythm disease were found in 15% of the population at 2 years.