Delayed depolarization and histologic abnormalities underlie the Brugada syndrome.

Brugada syndrome (BrS) is a controversial disease whose pathophysiology is still far from being fully understood. Unlike other cardiological disorders, a definite etiology has not yet been established so that it could be summarized under two main chapters: "functional" or "organic", "repolarization" or "depolarization" disorder. Despite initial descriptions leaned towards the organic substrate and delayed depolarization features, functional and repolarization theories have attracted most of the Cardiological attention for many years. Data from electrocardiography, endocavitary tracings, electroanatomic mapping and histopathology, however, demonstrated that BrS is mainly characterized by structural myocardial changes mostly at the right ventricular outflow tract (RVOT), but also at the right ventricle (RV) and by delayed conduction at the same sites. Conduction disorders at different levels may also be present and identify patients at high risk for major arrhythmic events. The aim of the present review is to provide the current state of art of the pathophysiology of BrS, focusing on electro-vectorcardiography and electrophysiological features, histopathology, echocardiography, and cardiac magnetic resonance imaging (CMRI).

Economic impact of remote monitoring after implantable defibrillators implantation in heart failure patients: an analysis from the EFFECT study.

AIMS: Heart failure (HF) patients with implantable cardioverter-defibrillators (ICD) require admissions for disease management and out-patient visits for disease management and assessment of device performance. These admissions place a significant burden on the National Health Service. Remote monitoring (RM) is an effective alternative to frequent hospital visits. The EFFECT study was a multicentre observational investigation aiming to evaluate the clinical effectiveness of RM compared with in-office visits standard management (SM). The present analysis is an economic evaluation of the results of the EFFECT trial. METHODS AND RESULTS: The present analysis considered the direct consumption of healthcare resources over 12-month follow-up. Standard tariffs were applied to hospitalizations, in-office visits and remote device interrogations. Economic comparisons were also carried out by means of propensity score (PS) analysis to take into account the lack of randomization in the study design. The analysis involved 858 patients with ICD or CRT-D. Of these, 401 (47%) were followed up via an SM approach, while 457 (53%) were assigned to RM. The rate of hospitalizations was 0.27/year in the SM group and 0.16/year in the RM group (risk reduction =0.59; P = 0.0004). In the non-adjusted analysis, the annual cost for each patient was €817 in the SM group and €604 in the RM group (P = 0.014). Propensity score analysis, in which 292 RM patients were matched with 292 SM patients, confirmed the results of the non-adjusted analysis (€872 in the SM group vs. €757 in the RM group; P < 0.0001). CONCLUSION: There is a reduction in direct healthcare costs of RM for HF patients with ICDs, particularly CRT-D, compared with standard monitoring. CLINICAL TRIAL REGISTRATION: http://clinicaltrials.gov/Identifier, NCT01723865.

Remote monitoring improves outcome after ICD implantation: the clinical efficacy in the management of heart failure (EFFECT) study.

AIMS: Internet-based remote interrogation systems have been shown to reduce emergency department and in-office visits in patients with implantable cardioverter defibrillators (ICDs), resulting in increased efficiency for healthcare providers. Nonetheless, studies sized to demonstrate the impact of remote monitoring on patients' outcome have been lacking. METHODS AND RESULTS: The EFFECT study was a multicentre clinical trial aimed at measuring and comparing the outcome of ICD patients conventionally followed-up by means of in-clinic visits (Standard arm) or by remote monitoring (Remote arm) in the clinical practice of 25 Italian centres. From 2011 to 2013, 987 consecutive patients were enrolled and followed up for at least 12 months. The primary endpoint was the rate of death and cardiovascular hospitalizations. Remote monitoring was adopted by 499 patients. Patients in the Standard and Remote arms did not differ significantly in terms of baseline clinical characteristics, except for a more frequent use of ICD with cardiac resynchronization therapy (CRT-D) in the Remote arm (48 vs. 36%, P < 0.001). One-year rates of the primary combined endpoint were 0.27 events/year for patients in the Standard arm and were 0.15 events/year for those in the Remote arm (incident rate ratio, 0.55; 95% CI, 0.41-0.73; P < 0.001). The endpoint rates in the Standard and Remote arms were 0.27 and 0.08 events/year, respectively, among CRT-D recipients (P < 0.001), and 0.28 vs. 0.21 among ICD patients (P = 0.094). The rates of in-office visits were 1.9 per year in the Standard arm and 1.7 per year in the Remote arm. CONCLUSION: Compared with the standard follow-up through in-office visits, remote monitoring is associated with reduced death and cardiovascular hospitalizations in patients with ICD in clinical practice. CLINICAL TRIAL REGISTRATION: URL: http://clinicaltrials.gov/ Identifier: NCT01723865.

Ventricular couplets but not isolated extrasystoles induce a "female" sustained, supraventricular tachycardia. What is the mechanism?

This is the case of a 28-year-old woman with sustained supraventricular tachycardia induced only by monomorphic ventricular couplets but not by isolated extrasystoles. The careful examination of electrocardiogram (ECG) was able to identify the mechanism of the tachycardia in the absence of electrophysiologic investigation. The tachycardia resulted sustained and symptomatic only during periods.

Manpower and outpatient clinic workload for remote monitoring of patients with cardiac implantable electronic devices: data from the HomeGuide Registry.

BACKGROUND: This study aimed to assess manpower and resource consumption of the HomeGuide workflow model for remote monitoring (Biotronik Home Monitoring [HM], Biotronik SE & Co. KG, Berlin, Germany) of cardiac implantable electronic devices in daily clinical practice. METHODS: The model established a cooperative interaction between a reference nurse (RN) for ordinary management, and a responsible physician (RP) for medical decisions in each outpatient clinic. RN reviewed remote transmissions and alerts, addressing critical cases to the RP. RESULTS: A total of 1,650 patients were enrolled in 75 sites: 25% pacemakers (PM), 22% dual-, 27% single-chamber implantable defibrillators (ICD), 2% PM with cardiac resynchronization therapy (CRT), and 24% ICD-CRT. During a median follow-up of 18 (10-31) months, 3,364 HM sessions were performed (74% by the RN, 26% by the RP) to complete 18,478 remote follow-ups. Median duration of remote follow-ups was 1.2 (0.6-2.0) minutes, corresponding to a manpower of 43.3 (4.2-94.8) minutes/month every 100 patients for nurses and 10.2 (0.1-31.1) for physicians (P < 0.0001). RN submitted 15% of remote transmissions to RP, who decided unscheduled follow-ups in 12% of the cases. The median manpower for phone calls was 1.9 (0.8-16.5) minutes/month every 100 contacted patients. There were 2.84 in-hospital visits/patient, 0.46 of which triggered by HM findings. A cumulative per-patient HM follow-up time of 15.4 minutes (20% of total follow-up time) allowed remote detection of 73% of actionable events. CONCLUSIONS: HM implemented in the HomeGuide workflow model required <1 hour/month every 100 patients to detect the majority of actionable events with limited administrative workload.

Remote follow-up of pacemakers in a selected population of debilitated elderly patients.

AIMS: The majority of patients with pacemakers are very elderly, many being >85-years old. They often suffer from serious illnesses and have great difficulty in walking. The aim of our study was to compare remote pacemaker monitoring with in-home checks of pacemakers, in terms of applicability, efficacy, and cost in a selected population of debilitated elderly patients. METHODS AND RESULTS: We selected 72 subjects (mean age 87 ± 8 years) among elderly debilitated patients with Medtronic pacemakers, compatible with the Carelink(®) remote monitoring system (13 patients with DDD pacemaker; 59 patients with single-lead VDD pacemaker). Remote follow-up was compared with in-home checks performed by nurses in 326 patients in similar clinical conditions. A total of 190 transmissions were received by remote monitoring (mean transmissions per month: 7.0; mean per patient: 2.6; range 1-6) during 27 months of follow-up. In this period, seven pacemakers were replaced owing to battery exhaustion, after a mean of 6.7 years from implantation. The occurrence of atrial or ventricular high-rate episodes was reported in 98 transmissions (53%). Nineteen patients died (annual mortality: 11.7%). On comparing the costs borne by the hospital for in-home checks, both for medical personnel and transportation, the estimated average saving was €32 per year per patient. CONCLUSION: Our study shows that the remote follow-up of pacemakers is a reliable, effective, and cost-saving procedure in elderly, debilitated patients. Moreover, remote controls provided an accurate and early diagnosis of arrhythmia occurrence.

Effectiveness of remote monitoring of CIEDs in detection and treatment of clinical and device-related cardiovascular events in daily practice: the HomeGuide Registry.

AIMS: The HomeGuide Registry was a prospective study (NCT01459874), implementing a model for remote monitoring of cardiac implantable electronic devices (CIEDs) in daily clinical practice, to estimate effectiveness in major cardiovascular event detection and management. METHODS AND RESULTS: The workflow for remote monitoring [Biotronik Home Monitoring (HM)] was based on primary nursing: each patient was assigned to an expert nurse for management and to a responsible physician for medical decisions. In-person visits were scheduled once a year. Seventy-five Italian sites enrolled 1650 patients [27% pacemakers, 27% single-chamber implantable cardioverter defibrillators (ICDs), 22% dual-chamber ICDs, 24% ICDs with cardiac resynchronization therapy]. Population resembled the expected characteristics of CIED patients. During a 20 ± 13 month follow-up, 2471 independently adjudicated events were collected in 838 patients (51%): 2033 (82%) were detected during HM sessions; 438 (18%) during in-person visits. Sixty were classified as false-positive, with generalized estimating equation-adjusted sensitivity and positive predictive value of 84.3% [confidence interval (CI), 82.5-86.0%] and 97.4% (CI, 96.5-98.2%), respectively. Overall, 95% of asymptomatic and 73% of actionable events were detected during HM sessions. Median reaction time was 3 days [interquartile range (IQR), 1-14 days]. Generalized estimating equation-adjusted incremental utility, calculated according to four properties of major clinical interest, was in favour of the HM sessions: +0.56 (CI, 0.53-0.58%), P < 0.0001. Resource consumption: 3364 HM sessions performed (76% by nurses), median committed monthly manpower of 55.5 (IQR, 22.0-107.0) min × health personnel/100 patients. CONCLUSION: Home Monitoring was highly effective in detecting and managing clinical events in CIED patients in daily practice with remarkably low manpower and resource consumption.

Prophylactic implantable defibrillator in patients with arrhythmogenic right ventricular cardiomyopathy/dysplasia and no prior ventricular fibrillation or sustained ventricular tachycardia.

BACKGROUND: The role of implantable cardioverter-defibrillator (ICD) in patients with arrhythmogenic right ventricular cardiomyopathy/dysplasia and no prior ventricular fibrillation (VF) or sustained ventricular tachycardia is an unsolved issue. METHODS AND RESULTS: We studied 106 consecutive patients (62 men and 44 women; age, 35.6±18 years) with arrhythmogenic right ventricular cardiomyopathy/dysplasia who received an ICD based on 1 or more arrhythmic risk factors such as syncope, nonsustained ventricular tachycardia, familial sudden death, and inducibility at programmed ventricular stimulation. During follow-up of 58±35 months, 25 patients (24%) had appropriate ICD interventions and 17 (16%) had shocks for life-threatening VF or ventricular flutter. At 48 months, the actual survival rate was 100% compared with the VF/ventricular flutter-free survival rate of 77% (log-rank P=0.01). Syncope significantly predicted any appropriate ICD interventions (hazard ratio, 2.94; 95% confidence interval, 1.83 to 4.67; P=0.013) and shocks for VF/ventricular flutter (hazard ratio, 3.16; 95% confidence interval, 1.39 to 5.63; P=0.005). The positive predictive value of programmed ventricular stimulation was 35% for any appropriate ICD intervention and 20% for shocks for VF/ventricular flutter, with a negative predictive value of 70% and 74%. None of the 27 asymptomatic patients with isolated familial sudden death had appropriate ICD therapy. Twenty patients (19%) had inappropriate ICD interventions, and 18 (17%) had device-related complications. CONCLUSIONS: One fourth of patients with arrhythmogenic right ventricular cardiomyopathy/dysplasia and no prior sustained ventricular tachycardia or VF had appropriate ICD interventions. Syncope was an important predictor of life-saving ICD intervention and is an indication for ICD. Prophylactic ICD may not be indicated in asymptomatic patients because of their low arrhythmic risk regardless of familial sudden death and programmed ventricular stimulation findings. Programmed ventricular stimulation had a low predictive accuracy for ICD therapy.

Management of alert messages in the remote monitoring of implantable cardioverter defibrillators and pacemakers: an Italian single-region study.

AIMS: The remote monitoring of pacemakers and implantable cardioverter defibrillators (ICDs) promotes accurate supervision of the patient and device. Alert settings appear to be a crucial parameter of its efficacy. The purpose of our study was to evaluate various settings for alerts and alert message management in patients with pacemakers and ICDs. METHODS AND RESULTS: We prospectively evaluated 282 patients (181 males, 101 females, mean age 72 ± 11 years) who were referred to nine electrophysiological centres in the Veneto region of Italy for a pacemaker (76 patients) or ICD (206 patients) implant in which remote monitoring was activated (Biotronik Home Monitoring®, Biotronik, Berlin, Germany). During a mean follow-up of 382 ± 261 days, we received 106,039 transmissions. In the pacemaker group, the alerts that were most frequently activated were those concerning battery exhaustion, surveying impedances, sensing and threshold measurements, as well as missing transmissions. In the ICD/ICD-cardiac resynchronization therapy group, the alerts nearly always activated were those concerning a detection setoff, battery exhaustion, critical values of impedance, or ineffective maximum energy shock. In both groups, the alarms for heart rate monitoring and supraventricular arrhythmia were activated in fewer cases at higher variability among centres. CONCLUSIONS: Our study demonstrates that more attention is paid to critical technical data than to patients' clinical profiles, probably to limit an excessive flow of data into the centre. Accurate alert settings, personalized to the patients' features, are essential for easier and more effective management of patients who are followed remotely.

Recommendations for interpretation of 12-lead electrocardiogram in the athlete.

Cardiovascular remodelling in the conditioned athlete is frequently associated with physiological ECG changes. Abnormalities, however, may be detected which represent expression of an underlying heart disease that puts the athlete at risk of arrhythmic cardiac arrest during sports. It is mandatory that ECG changes resulting from intensive physical training are distinguished from abnormalities which reflect a potential cardiac pathology. The present article represents the consensus statement of an international panel of cardiologists and sports medical physicians with expertise in the fields of electrocardiography, imaging, inherited cardiovascular disease, cardiovascular pathology, and management of young competitive athletes. The document provides cardiologists and sports medical physicians with a modern approach to correct interpretation of 12-lead ECG in the athlete and emerging understanding of incomplete penetrance of inherited cardiovascular disease. When the ECG of an athlete is examined, the main objective is to distinguish between physiological patterns that should cause no alarm and those that require action and/or additional testing to exclude (or confirm) the suspicion of an underlying cardiovascular condition carrying the risk of sudden death during sports. The aim of the present position paper is to provide a framework for this distinction. For every ECG abnormality, the document focuses on the ensuing clinical work-up required for differential diagnosis and clinical assessment. When appropriate the referral options for risk stratification and cardiovascular management of the athlete are briefly addressed.

Asymptomatic right ventricular perforation by an implantable cardioverter defibrillator lead detected by home monitoring system.

Right ventricular lead perforation is a rare but serious and potentially life-threatening complication of pacemaker or defibrillator lead implantation. This report describes a patient with Brugada syndrome in whom the diagnosis of asymptomatic right ventricular perforation by an implantable cardioverter defibrillator lead was detected 12 days after implantation, thanks to a report from home monitoring system. The patient was admitted to our institution, where the lead was explanted and replaced. This case illustrates the potential lifesaving benefit of the home monitoring system in patients with implantable cardioverter defibrillator.

Daily Exposure to Air Pollution Particulate Matter Is Associated with Atrial Fibrillation in High-Risk Patients.

Several epidemiological studies found an association between acute exposure to fine particulate matter of less than 2.5 µm and 10 µm in aerodynamic diameter (PM2.5 and PM10) and cardiovascular diseases, ventricular fibrillation incidence and mortality. The effects of pollution on atrial fibrillation (AF) beyond the first several hours of exposure remain controversial. A total of 145 patients with implantable cardioverter-defibrillators (ICDs), cardiac resynchronization therapy defibrillators (ICD-CRT), or pacemakers were enrolled in this multicentric prospective study. Daily levels of PM2.5 and PM10 were collected from monitoring stations within 20 km of the patient's residence. A Firth Logistic Regression model was used to evaluate the association between AF and daily exposure to PM2.5 and PM10. Exposure levels to PM2.5 and PM10 were moderate, being above the World Health Organization (WHO) PM2.5 and PM10 thresholds of 25 µg/m3 and 50 µg/m3, respectively, on 26% and 18% of the follow-up days. An association was found between daily levels of PM2.5 and PM10 and AF (95% confidence intervals (CIs) of 1.34-2.40 and 1.44-4.28, respectively) for an increase of 50 µg/m3 above the WHO threshold. Daily exposure to moderate PM2.5 and PM10 levels is associated with AF in patients who are not prone to AF.

Implantable cardioverter-defibrillators and prevention of sudden cardiac death in hypertrophic cardiomyopathy.

CONTEXT: Recently, the implantable cardioverter-defibrillator (ICD) has been promoted for prevention of sudden death in hypertrophic cardiomyopathy (HCM). However, the effectiveness and appropriate selection of patients for this therapy is incompletely resolved. OBJECTIVE: To study the relationship between clinical risk profile and incidence and efficacy of ICD intervention in HCM. DESIGN, SETTING, AND PATIENTS: Multicenter registry study of ICDs implanted between 1986 and 2003 in 506 unrelated patients with HCM. Patients were judged to be at high risk for sudden death; had received ICDs; underwent evaluation at 42 referral and nonreferral institutions in the United States, Europe, and Australia; and had a mean follow-up of 3.7 (SD, 2.8) years. Measured risk factors for sudden death included family history of sudden death, massive left ventricular hypertrophy, nonsustained ventricular tachycardia on Holter monitoring, and unexplained prior syncope. MAIN OUTCOME MEASURE: Appropriate ICD intervention terminating ventricular tachycardia or fibrillation. RESULTS: The 506 patients were predominately young (mean age, 42 [SD, 17] years) at implantation, and most (439 [87%]) had no or only mildly limiting symptoms. ICD interventions appropriately terminated ventricular tachycardia/fibrillation in 103 patients (20%). Intervention rates were 10.6% per year for secondary prevention after cardiac arrest (5-year cumulative probability, 39% [SD, 5%]), and 3.6% per year for primary prevention (5-year probability, 17% [SD, 2%]). Time to first appropriate discharge was up to 10 years, with a 27% (SD, 7%) probability 5 years or more after implantation. For primary prevention, 18 of the 51 patients with appropriate ICD interventions (35%) had undergone implantation for only a single risk factor; likelihood of appropriate discharge was similar in patients with 1, 2, or 3 or more risk markers (3.83, 2.65, and 4.82 per 100 person-years, respectively; P = .77). The single sudden death due to an arrhythmia (in the absence of advanced heart failure) resulted from ICD malfunction. ICD complications included inappropriate shocks in 136 patients (27%). CONCLUSIONS: In a high-risk HCM cohort, ICD interventions for life-threatening ventricular tachyarrhythmias were frequent and highly effective in restoring normal rhythm. An important proportion of ICD discharges occurred in primary prevention patients who had undergone implantation for a single risk factor. Therefore, a single marker of high risk for sudden death may be sufficient to justify consideration for prophylactic defibrillator implantation in selected patients with HCM.

Association between air pollution and ventricular arrhythmias in high-risk patients (ARIA study): a multicentre longitudinal study.

BACKGROUND: Although the effects of air pollution on mortality have been clearly shown in many epidemiological and observational studies, the pro-arrhythmic effects remain unknown. We aimed to assess the short-term effects of air pollution on ventricular arrhythmias in a population of high-risk patients with implantable cardioverter-defibrillators (ICDs) or cardiac resynchronisation therapy defibrillators (ICD-CRT). METHODS: In this prospective multicentre study, we assessed 281 patients (median age 71 years) across nine centres in the Veneto region of Italy. Episodes of ventricular tachycardia and ventricular fibrillation that were recorded by the diagnostic device were considered in this analysis. Concentrations of particulate matter of less than 10 µm (PM10) and less than 2·5 µm (PM2·5) in aerodynamic diameter, carbon monoxide, nitrogen dioxide, sulphur dioxide, and ozone were obtained daily from monitoring stations, and the 24 h median value was considered. Each patient was associated with exposure data from the monitoring station that was closest to their residence. Patients were followed up for 1 year and then scheduled to have a closing visit, within 1 more year. This study is registered with ClinicalTrials.gov, number NCT01723761. FINDINGS: Participants were enrolled from April 1, 2011, to Sept 30, 2012, and follow-ups (completed on April 5, 2014) ranged from 637 to 1177 days (median 652 days). The incidence of episodes of ventricular tachycardia and ventricular fibrillation correlated significantly with PM2·5 (p<0·0001) but not PM10. An analysis of ventricular fibrillation episodes alone showed a significant increase in risk of higher PM2·5 (p=0·002) and PM10 values (p=0·0057). None of the gaseous pollutants were significantly linked to the occurrence of ventricular tachycardia or ventricular fibrillation. In a subgroup analysis of patients with or without a previous myocardial infarction, only the first showed a significant association between particulate matter and episodes of ventricular tachycardia or ventricular fibrillation. INTERPRETATION: Particulate matter has acute pro-arrhythmic effects in a population of high-risk patients, which increase on exposure to fine particles and in patients who have experienced a previous myocardial infarction. The time sequence of the arrhythmic events suggests there is an underlying neurally mediated mechanism. From a clinical point of view, the results of our study should encourage physicians to also consider environmental risk when addressing the prevention of arrhythmic events, particularly in patients with coronary heart disease, advising them to avoid exposure to high levels of fine particulate matter. FUNDING: There was no funding source for this study.

Three-dimensional electroanatomic voltage mapping increases accuracy of diagnosing arrhythmogenic right ventricular cardiomyopathy/dysplasia.

BACKGROUND: Three-dimensional electroanatomic voltage mapping offers the potential to identify low-voltage areas that correspond to regions of right ventricular (RV) myocardial loss and fibrofatty replacement in patients with arrhythmogenic RV cardiomyopathy/dysplasia (ARVC/D). METHODS AND RESULTS: Thirty-one consecutive patients (22 men and 9 women; mean age, 30.8+/-7 years) who fulfilled the criteria of the Task Force of the European Society of Cardiology and International Society and Federation of Cardiology (ESC/ISFC) for ARVC/D diagnosis after noninvasive clinical evaluation underwent further invasive study including RV electroanatomic voltage mapping and endomyocardial biopsy (EMB) to validate the diagnosis. Multiple RV endocardial, bipolar electrograms (175+/-23) were sampled during sinus rhythm. Twenty patients (group A; 65%) had an abnormal RV electroanatomic voltage mapping showing > or =1 area (mean 2.25+/-0.7) with low-voltage values (bipolar electrogram amplitude <0.5 mV), surrounded by a border zone (0.5 to 1.5 mV) that transitioned into normal myocardium (>1.5 mV). Low-voltage electrograms appeared fractionated with significantly prolonged duration and delayed activation. In 11 patients (group B; 35%), electroanatomic voltage mapping was normal, with preserved electrogram voltage (4.4+/-0.7 mV) and duration (37.2+/-0.9 ms) throughout the RV. Low-voltage areas in patients from group A corresponded to echocardiographic/angiographic RV wall motion abnormalities and were significantly associated with myocyte loss and fibrofatty replacement at EMB (P<0.0001) and familial ARVC/D (P<0.0001). Patients from group B had sporadic disease and histopathological evidence of inflammatory cardiomyopathy (P<0.0001). During the time interval from onset of symptoms to the invasive study, 11 patients (55%) with electroanatomic low-voltage regions received an implantable cardioverter/defibrillator because of life-threatening ventricular arrhythmias, whereas all but 1 patient with a normal voltage map remained stable on antiarrhythmic drug therapy (P=0.02). CONCLUSIONS: Three-dimensional electroanatomic voltage mapping enhanced accuracy for diagnosing ARVC/D (1) by demonstrating low-voltage areas that were associated with fibrofatty myocardial replacement and (2) by identifying a subset of patients who fulfilled ESC/ISFC Task Force diagnostic criteria but showed a preserved electrogram voltage, an inflammatory cardiomyopathy mimicking ARVC/D, and a better arrhythmic outcome.

Contribution of decreased atrial function in the pathogenesis of neurally mediated syncope.

One of the most important mechanisms proposed in the pathogenesis of neurally mediated syncope considers the stimulation of myocardial mechanoreceptors as the final trigger leading to reflex hypotension and bradycardia. The aim of our study was to analyze the modifications of systolic and diastolic velocities of the left ventricle by tissue Doppler echocardiography, during the upright tilt test, to confirm the presence of an increased ventricular contractility before syncope. We evaluated 47 patients (mean age 43 years) with unexplained syncope and 13 healthy subjects. Three echocardiographic recordings were collected: at baseline, during the initial 5 minutes of the test, and after 15 minutes of tilt. The upright tilt test was positive in 28 patients. During the test, all of them had a similar, significant, progressive reduction of left ventricular end-diastolic volume, left atrial area, and left atrial volume. In contrast, the left ventricular ejection fraction showed an early, more pronounced decrease in those with positive tests. By tissue Doppler echocardiography, the systolic waves remained almost unchanged, and the early filling waves decreased similarly in those with positive or negative findings and the controls. In contrast, the atrial filling waves showed a significant decrease only in patients with positive tests. In conclusion, our study did not find increased ventricular contractility before syncope. In contrast, a decreased atrial contribution to ventricular filling characterized patients with positive upright tilt test results, which, we postulate, may be an important contributory factor to vasovagal syncope.

Association between remote implantable cardioverter defibrillator monitoring and beta-blocker utilization: An analysis from the EFFECT study.

INTRODUCTION: A substantial number of heart failure patients undergoing implantation of implantable cardioverter defibrillators (ICDs) fail to receive beta-blockers, or receive them at a suboptimal dose. Remote monitoring (RM) is becoming the standard means of following up recipients of ICDs. However, the impact of this shift toward remote ICD follow-up on the quality of drug therapy management in current clinical practice is unknown. The present analysis was aimed at investigating the impact of RM on the dose of beta-blockers achieved, and its association with clinical outcome at 12 months. METHODS: Altogether 987 consecutive patients were enrolled and followed up for at least 12 months in 25 Italian centres. RM was adopted by 499 patients. RESULTS: The number of patients receiving beta-blockers at any dose decreased after 12 months (from 403 (81%) to 370 (74%) for the remote arm and from 389 (80%) to 342 (70%) for the standard arm, both p < 0.02). Nonetheless, the number of patients on beta-blockers at the effective dose increased in both arms (from 60 (12%) to 82 (16%) for remote and from 63 (13%) to 98 (20%) for standard arms respectively, both p < 0.05). At multivariate analysis, RM was not associated with an effective dose of beta-blockers at the follow-up evaluation. However, the adoption of RM (p = 0.003) and the achievement of the effective dose of beta-blockers (p = 0.006) were independently and positively associated with an improved outcome. DISCUSSION: In a 'real-world' setting, we did not find an association between RM and the achieved dose of beta-blockers. However, we reported outcome benefits in achieving the effective dose of beta-blockers during follow-up and in adopting RM.

Implantable cardioverter-defibrillator therapy for prevention of sudden death in patients with arrhythmogenic right ventricular cardiomyopathy/dysplasia.

BACKGROUND: Arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) is a condition associated with the risk of sudden death (SD). METHODS AND RESULTS: We conducted a multicenter study of the impact of the implantable cardioverter-defibrillator (ICD) for prevention of SD in 132 patients (93 males and 39 females, age 40+/-15 years) with ARVC/D. Implant indications were a history of cardiac arrest in 13 patients (10%), sustained ventricular tachycardia in 82 (62%), syncope in 21 (16%), and other in 16 (12%). During a mean follow-up of 39+/-25 months, 64 patients (48%) had appropriate ICD interventions, 21 (16%) had inappropriate interventions, and 19 (14%) had ICD-related complications. Fifty-three (83%) of the 64 patients with appropriate interventions received antiarrhythmic drug therapy at the time of first ICD discharge. Programmed ventricular stimulation was of limited value in identifying patients at risk of tachyarrhythmias during the follow-up (positive predictive value 49%, negative predictive value 54%). Four patients (3%) died, and 32 (24%) experienced ventricular fibrillation/flutter that in all likelihood would have been fatal in the absence of the device. At 36 months, the actual patient survival rate was 96% compared with the ventricular fibrillation/flutter-free survival rate of 72% (P<0.001). Patients who received implants because of ventricular tachycardia without hemodynamic compromise had a significantly lower incidence of ventricular fibrillation/flutter (log rank=0.01). History of cardiac arrest or ventricular tachycardia with hemodynamic compromise, younger age, and left ventricular involvement were independent predictors of ventricular fibrillation/flutter. CONCLUSIONS: In patients with ARVC/D, ICD therapy provided life-saving protection by effectively terminating life-threatening ventricular arrhythmias. Patients who were prone to ventricular fibrillation/flutter could be identified on the basis of clinical presentation, irrespective of programmed ventricular stimulation outcome.