Catecholamine response to exercise in patients with non-obstructive hypertrophic cardiomyopathy.

KEY POINTS: Intense physical activity, a potent stimulus for sympathetic nervous system activation, is thought to increase the risk of malignant ventricular arrhythmias among patients with hypertrophic cardiomyopathy (HCM). As a result, the majority of patients with HCM deliberately reduce their habitual physical activity after diagnosis and this lifestyle change puts them at risk for sequelae of a sedentary lifestyle: weight gain, hypertension, hyperlipidaemia, insulin resistance, coronary artery disease, and increased morbidity and mortality. We show that plasma catecholamine levels remain stably low at exercise intensities below the ventilatory threshold, a parameter that can be defined during cardiopulmonary exercise testing, but rise rapidly at higher intensities of exercise. These findings suggest that cardiopulmonary exercise testing may be a useful tool to provide an individualized moderate-intensity exercise prescription for patients with HCM. ABSTRACT: Intense physical activity, a potent stimulus for sympathetic nervous system activation, is thought to increase the risk of malignant ventricular arrhythmias among patients with hypertrophic cardiomyopathy (HCM). However, the impact of exercise intensity on plasma catecholamine levels among HCM patients has not been rigorously defined. We conducted a prospective observational case-control study of men with non-obstructive HCM and age-matched controls. Laboratory-based cardiopulmonary exercise testing coupled with serial phlebotomy was used to define the relationship between exercise intensity and plasma catecholamine levels. Compared to controls (C, n = 5), HCM participants (H, n = 9) demonstrated higher left ventricular mass index (115 ± 20 vs. 90 ± 16 g/m2 , P = 0.03) and maximal left ventricular wall thickness (16 ± 1 vs. 8 ± 1 mm, P < 0.001) but similar body mass index, resting heart rate, peak oxygen consumption (H = 40 ± 13 vs. C = 42 ± 7 ml/kg/min, P = 0.81) and heart rate at the ventilatory threshold (H = 78 ± 6 vs. C = 78 ± 4% peak heart rate, P = 0.92). During incremental effort exercise in both groups, concentrations of adrenaline and noradrenaline were unchanged through low- and moderate-exercise intensity until reaching a catecholamine threshold (H = 82 ± 4 vs. C = 85 ± 3% peak heart rate, P = 0.86) after which levels of both molecules rose rapidly. In patients with mild non-obstructive HCM, plasma catecholamine levels remain stably low at exercise intensities below the ventilatory threshold but rise rapidly at higher intensities of exercise. Routine cardiopulmonary exercise testing may be a useful tool to provide an individualized moderate-intensity exercise prescription for patients with HCM.

Nonalcoholic Steatohepatitis is Associated with Cardiac Remodeling and Dysfunction.

OBJECTIVE: Preliminary data suggest that nonalcoholic fatty liver disease is associated with early heart failure (HF). However, whether nonalcoholic steatohepatitis (NASH) is directly associated with echocardiographic changes in cardiac structure or function remains unknown. METHODS: A retrospective cohort was identified of individuals (N = 65) without known heart disease, undergoing elective bariatric surgery with perioperative liver biopsy, and available recent transthoracic echocardiography (TTE). TTE measures were evaluated by NASH status using correlation coefficients, ANOVA, and linear regression, accounting for cardiometabolic factors. RESULTS: Median age was 47 years; 22% (n = 14) had NASH. NASH patients had increased median left atrial (LA) volume (28.6 mL/m2 vs. 24.8 mL/m2 ; P < 0.0001) and left ventricular (LV) mass (82.6 g/m2 vs. 78.6 g/m2 ; P < 0.0001), indexed for height. NASH was inversely correlated with indices of diastolic function, including septal E' (r = -0.90 [95% CI: -1.21 to -0.42]; P = 0.020) and E:A (r = -0.31 [95% CI: -0.51 to -0.09]; P = 0.037). In adjusted analyses, NASH remained associated with increased LV mass index (ß1 = 7.16 [SE: 4.95]; P = 0.001) and LA volume index (ß1 = 0.19 [SE: 0.08]; P = 0.001) and reduced lateral and septal E' (ß1 = -0.91, P = 0.015; ß1 = -0.89, P = 0.047, respectively). CONCLUSIONS: In this bariatric cohort, NASH was associated with changes in myocardial structure and in load-dependent indices of LV diastolic function, suggestive of subclinical HF.

Trials of Quality Improvement in Imaging.

Cardiovascular imaging plays a central role in the diagnosis and treatment of cardiovascular disease. Recently, increased emphasis has been placed on quality in cardiovascular imaging, and it is becoming a central priority for various stakeholders, including patients, physicians, and payers. The changing health care landscape and associated challenges imposed on cardiac imagers, including reductions in reimbursement and growing need for pre-authorization, have also helped bring quality metrics to the forefront. Continuous quality improvement initiatives provide the framework for the team of physicians, technical staff members, administrators, and other health care professionals to deliver high-quality care. Efforts to improve quality in cardiac imaging have started to form the foundation for numerous research studies in this arena, and although few in number, randomized control trials have begun to emerge. This review highlights quality improvement studies focusing on appropriate use education, reporting, and radiation dose reduction in cardiovascular imaging.

Effect of Release of the First Pediatric Appropriate Use Criteria on Transthoracic Echocardiogram Ordering Practice.

Pediatric appropriate use criteria (AUC) were recently published for initial outpatient transthoracic echocardiography (TTE). The purpose of this study was to determine the effect of AUC publication on TTE ordering patterns of pediatric cardiologists. Data were prospectively collected on patients who had initial outpatient TTE ordered before (phase I, April to September 2014) and 3 months after (phase II, January to April 2015) AUC document publication at 6 centers. Site investigators assessed each study's indication and assigned AUC appropriateness as "appropriate" (A), "may be appropriate" (M), "rarely appropriate" (R), or "unclassifiable." One hundred three physicians ordered 4,562 TTEs (2,655 phase I and 1,907 phase II). Overall, there was no statistically significant change in the proportion of A, M, or unclassifiable, but R decreased (12.0% to 9.6%, p = 0.01). There was significant variability among the centers in the percentage of studies for indications rated R (4.9% to 34.8%). There was no significant change in any of the appropriateness ratings at 4 centers, a decrease in R and an increase in A at 1 and a decrease in R and increase in unclassifiable at another. The first pediatric AUC document had only a small impact on physician ordering behavior for initial TTEs, including a small decrease in R. There was a significant variability in appropriateness of studies among centers. These data suggest that active educational interventions are required to substantially improve the appropriate use of pediatric TTE in the outpatient setting.

Cardiovascular Risk and Disease Among Masters Endurance Athletes: Insights from the Boston MASTER (Masters Athletes Survey To Evaluate Risk) Initiative.

BACKGROUND: Masters athletes (MAs), people over the age of 35 that participate in competitive sports, are a rapidly growing population that may be uniquely at risk for cardiovascular (CV) disease. The objective of this study was to develop a comprehensive clinical CV profile of MA. METHODS: An electronic Internet-based survey (survey response rate = 66 %) was used to characterize a community cohort of MAs residing in Eastern Massachusetts, USA. Clinical and lifestyle factors associated with prevalent CV disease were determined using logistic regression. RESULTS: Among 591 MAs (66 % men, age = 50 ± 9 years) with 21.3 ± 5.5 years of competitive endurance sport exposure, at least one CV risk factor was present in 64 % including the following: family history of premature atherosclerosis (32 %), prior/current tobacco exposure (23 %), hypertension (12.0 %), and dyslipidemia (7.4 %). There was a 9 % (54/591) prevalence of established CV disease which was accounted for largely by atrial fibrillation (AF) and coronary atherosclerosis (CAD). Prevalent AF was associated with years of exercise exposure [adjusted odds ratio, OR (95 % confidence intervals); OR = 1.10 (1.06, 1.21)] and hypertension [OR = 1.05 (1.01, 1.10)] while CAD was associated with dyslipidemia [OR = 9.09 (2.40, 34.39)] and tobacco use [OR = 1.78 (1.34, 3.10)] but was independent of exercise exposure. CONCLUSIONS: Among MAs, AF is associated with prior exercise exposure whereas CAD is associated with typical risk factors including dyslipidemia and prior tobacco use. These findings suggest that there are numerous opportunities to improve disease prevention and clinical care in this population.

Effect of Educational Intervention on the Rate of Rarely Appropriate Outpatient Echocardiograms Ordered by Attending Academic Cardiologists: A Randomized Clinical Trial.

Importance: Appropriate use criteria-based educational initiatives have been shown to improve transthoracic echocardiography (TTE) ordering practices of physicians in training. Whether such an intervention is successful with attending cardiologists remains unknown. Objective: To prospectively investigate the effect of an appropriate use criteria-based educational intervention on ordering of outpatient TTEs by attending academic cardiologists. Design, Setting, and Participants: We conducted a prospective, randomized clinical trial of an educational intervention designed to reduce the number of outpatient TTEs that were deemed to be rarely appropriate by published appropriate use criteria. Investigators classifying TTEs were blinded to participant groupings. The study was conducted within the cardiology division at the Massachusetts General Hospital, an academic quaternary care hospital. Staff members of the cardiology division were included; 66 cardiologists were randomized. The study was conducted from November 19, 2013, to June 1, 2014. An analysis of the evaluable population was performed. Interventions: The appropriate use criteria-based educational intervention consisted of a review lecture and electronic information card, as well as monthly individual physician feedback via email. The email described the percentage of rarely appropriate TTEs as well as the appropriate use criteria rationale for classifying studies as rarely appropriate. Main Outcomes and Measures: We hypothesized a priori that the educational intervention would reduce the number of rarely appropriate TTEs. The primary outcome was the rate of rarely appropriate TTEs. Results: Of the 66 cardiologists enrolled in the study, 65 were included in the analysis (1 intervention cardiologist retired from practice during the study). The participants' mean (SD) age was 50.6 (10.5) years; 48 (73%) were men. Following intervention, the proportion of rarely appropriate TTEs was significantly lower in the intervention vs control group (143 of 1359 [10.5%] vs 285 of 1728 [16.5%]; odds ratio [OR], 0.59 [95% CI, 0.39-0.88]; P = .01), and there was a nonsignificant increase in the proportion of appropriate TTEs in the intervention vs control group (1054 [77.6%] vs 1244 [72.0%]; OR, 1.38 [95% CI, 0.93-2.05]; P = .11). The most common of the 428 rarely appropriate indications were routine surveillance within 3 years after prosthetic valve insertion (73 [17.1%]), routine surveillance within 1 year for moderate or severe valvular stenosis (64 [15.0%]), and routine surveillance of cardiomyopathy (45 [10.5%]) or ventricular function (36 [8.4%]). Conclusions and Relevance: An appropriate use criteria-based educational and feedback intervention reduced the number of rarely appropriate TTEs ordered by attending academic cardiologists. This strategy may be feasible to improve TTE utilization among cardiologists, and this type of intervention warrants study in other practice environments. Trial Registration: clinicalrials.gov Identifier: NCT01968642.

Effect of growth hormone treatment on diastolic function in patients who have developed growth hormone deficiency after definitive treatment of acromegaly.

OBJECTIVE: Although growth hormone (GH) replacement is prescribed for patients with hypopituitarism due to many etiologies, it is not routinely prescribed for patients with GH deficiency (GHD) after cure of acromegaly (acroGHD). This study was designed to investigate the effect of GH replacement on cardiac parameters in acroGHD. DESIGN: We prospectively evaluated for 12months 23 patients with acroGHD: 15 subjects on GH replacement and eight subjects not on GH replacement. Main outcome measures included LV mass corrected for body surface area (LVM/BSA) and measures of diastolic dysfunction (E/A ratio and deceleration time), as assessed by echocardiography. RESULTS: After 12months of follow-up, there were no differences between the GH-treated group and the untreated group in LVM/BSA (GH: 74.4±22.5g/m(2) vs untreated: 72.9±21.3g/m(2), p=0.89), E/A ratio (GH: 1.21±0.39 vs untreated: 1.08±0.39, p=0.50) or deceleration time (GH: 224.5±60.1ms vs untreated: 260±79.8ms, p=0.32). The overall degree of diastolic function was similar between the groups with 42.9% of untreated subjects and 50% of GH-treated subjects (p=0.76) classified as having normal diastolic function at follow-up. CONCLUSIONS: There were no significant differences in LVM/BSA or parameters of diastolic function in patients with a history of acromegaly treated for GHD as compared to those who were untreated. These data are reassuring with respect to cardiovascular safety with GH use after treatment for acromegaly, although further longer term study is necessary to evaluate the safety and efficacy of GH treatment in this population.

Design and methods of the Echo WISELY (Will Inappropriate Scenarios for Echocardiography Lessen SignificantlY) study: An investigator-blinded randomized controlled trial of education and feedback intervention to reduce inappropriate echocardiograms.

BACKGROUND: Appropriate use criteria (AUC) for transthoracic echocardiography (TTE) were developed to address concerns regarding inappropriate use of TTE. A previous pilot study suggests that an educational and feedback intervention can reduce inappropriate TTEs ordered by physicians in training. It is unknown if this type of intervention will be effective when targeted at attending level physicians in a variety of clinical settings. AIMS: The aim of this international, multicenter study is to evaluate the hypothesis that an AUC-based educational and feedback intervention will reduce the proportion of inappropriate echocardiograms ordered by attending physicians in the ambulatory environment. METHODS: In an ongoing multicentered, investigator-blinded, randomized controlled trial across Canada and the United States, cardiologists and primary care physicians practicing in the ambulatory setting will be enrolled. The intervention arm will receive (1) a lecture outlining the AUC and most recent available evidence highlighting appropriate use of TTE, (2) access to the American Society of Echocardiography mobile phone app, and (3) individualized feedback reports e-mailed monthly summarizing TTE ordering behavior including information on inappropriate TTEs and brief explanations of the inappropriate designation. The control group will receive no education on TTE appropriate use and order TTEs as usual practice. CONCLUSIONS: The Echo WISELY (Will Inappropriate Scenarios for Echocardiography Lessen Significantly in an education RCT) study is the first multicenter randomized trial of an AUC-based educational intervention. The study will examine whether an education and feedback intervention will reduce the rate of outpatient inappropriate TTEs ordered by attending level cardiologists and primary care physicians (www.clinicaltrials.gov identifier NCT02038101).

Educational intervention to reduce inappropriate transthoracic echocardiograms: the need for sustained intervention.

BACKGROUND: We previously demonstrated that an Appropriate Use Criteria (AUC)-based educational intervention reduced inappropriate transthoracic echocardiograms (TTE) on an inpatient medical service. Whether improved TTE ordering is sustained after discontinuation of the intervention is unknown. METHODS: We conducted a prospective, time series analysis of an educational intervention designed to reduce inappropriate TTE. Ordering patterns during the intervention were compared with a preintervention control period and a postintervention period. The goal of the present analysis was to determine the TTE ordering patterns after discontinuation of the educational intervention. The primary outcome was the proportion of inappropriate TTEs. RESULTS: Using the 2011 AUC 99.2% of all TTEs were classifiable. Compared to the control, there was a 26% reduction in the number of TTEs ordered per day during the intervention (3.9 vs. 2.9 TTEs, P < 0.001), but no significant difference between the intervention and postintervention periods (2.9 vs. 3.1, P = 0.23). The intervention produced a decrease in the inappropriate TTE rate and an increase in the appropriate TTE rate. Compared to the intervention, in the postintervention period the rate of inappropriate TTEs increased (5% vs. 11%, P = 0.01) and appropriate TTEs decreased (93% vs. 86%, P = 0.008). The postintervention rate of inappropriate TTEs was similar to the preintervention control period (11% vs. 13%, P = 0.23). CONCLUSIONS: Following completion of an AUC-based educational intervention the proportion of inappropriate TTEs increased to the preintervention level. The long-term success of an intervention designed to improve appropriate utilization of TTE requires a sustained effort of education and feedback.

An educational intervention reduces the rate of inappropriate echocardiograms on an inpatient medical service.

OBJECTIVES: This study sought to prospectively study the impact of an appropriate use criteria (AUC)-based educational intervention on transthoracic echocardiography (TTE) ordering among house staff on the inpatient general internal medicine service at an academic medical center. BACKGROUND: AUC for TTE were developed in response to concerns about inappropriate use of TTE. To date, educational interventions based on the AUC to reduce inappropriate use of TTE have not been prospectively studied. METHODS: A prospective, time series analysis of an educational intervention was conducted and then compared with TTE ordering on the same medical service during a control period. The intervention consisted of: 1) a lecture to house staff on the 2011 AUC for TTE; 2) a pocket card that applied the AUC to common clinical scenarios; and 3) biweekly e-mail feedback regarding ordering behavior. TTE ordering was tracked over the intervention period on a daily basis and feedback reports were e-mailed at 2-week intervals. The primary outcome was the proportion of inappropriate and appropriate TTE ordered during the intervention period. RESULTS: Of all TTEs ordered in the control and study periods, 99% and 98%, respectively, were classifiable using the 2011 AUC. During the study period, there was a 26% reduction in the number of TTE ordered per day compared with the number ordered during the control period (2.9 vs. 3.9 TTE, p < 0.001). During the study period, the proportion of inappropriate TTE was significantly lower (5% vs. 13%, p < 0.001) and the proportion of appropriate TTE was significantly higher (93% vs. 84%, p < 0.001). CONCLUSIONS: A simple educational intervention produced a significant reduction in the proportion of inappropriate TTE and increased the proportion of appropriate TTE ordered on an inpatient academic medical service. This study provides a practical approach for using the AUC to reduce the number of inappropriate TTE. Further study in other practice environments is warranted.

The feasibility, diagnostic yield, and learning curve of portable echocardiography for out-of-hospital cardiovascular disease screening.

BACKGROUND: The reduction in the size of full-capability echocardiographic machines facilitates "out-of-hospital" transthoracic echocardiography (TTE). Data documenting the feasibility, yield, and logistical considerations of out-of-hospital TTE for preparticipation evaluation of athletes are sparse. METHODS: A multiyear study was conducted to examine the role of 12-lead electrocardiography for athlete screening in which TTE was used to document or exclude underlying structural heart disease. Using a commercially available portable transthoracic echocardiographic system, the rate of technically adequate imaging, diagnostic yield, and the time required for the completion of TTE (including setup, performance, and interpretation) were examined. TTE was performed in university medical offices and at "out-of-office" athletic facilities. Measurements were recorded during each year of the study to determine the impact of targeted attempts to improve efficiency. RESULTS: Four hundred sixty-seven of 510 participants had transthoracic echocardiographic images that were technically adequate for complete interpretation (imaging success rate, 92%). Echocardiographic evidence of physiologic, exercise-induced cardiac remodeling was observed in 110 of 510 (22%). Cardiac abnormalities with relevance to sports participation risk were detected in 11 of 508 participants (2.2%). Over 3 years, the average time for the completion of TTE (including setup, imaging, and interpretation) decreased (year 1, 17.4 ± 3 min; year 2, 14.0 ± 2.1 min; year 3, 11.0 ± 1.8 min; P < .001). This was driven by a significant decrease in the time required for TTE at out-of-office athletic facilities. CONCLUSIONS: Community-based TTE in athletes is feasible and is associated with a high rate of technically adequate imaging. Importantly, there appears to be a significant learning curve associated with out-of-hospital TTE.

Performance of the 2010 European Society of Cardiology criteria for ECG interpretation in athletes.

BACKGROUND: The European Society of Cardiology (ESC) recently published revised criteria for ECG interpretation in the athlete. OBJECTIVE: To examine the performance of the 2010 ESC ECG criteria in a population of athletes undergoing preparticipation cardiovascular disease screening. METHODS: University athletes (n=508) underwent routine medical history/physical examination and ECG before athletic participation. Transthoracic echocardiography (TTE) was also performed on each participant to detect or exclude cardiac findings with relevance to sport participation. Screening test statistics were calculated to determine the performance of the 2010 ESC criteria, and the performance of the 2010 criteria was compared with the 2005 criteria. RESULTS: Application of the 2010 ESC criteria, compared with the 2005 criteria, reduced the number of participants with abnormal ECG findings from 83/508 (16.3%) to 49/508 (9.6%). The reduction in the number of abnormal ECGs was driven by the reclassification of participants with isolated QRS voltage criteria for left ventricular hypertrophy from abnormal to normal. Of the 49 participants with abnormal ECGs, 14/49 (29%) had a single ECG abnormality and 35/49 (71%) had two or more abnormalities. The use of the 2010 criteria was associated with improved specificity (reduction in the false positive rate) and preserved sensitivity when compared with the 2005 criteria. CONCLUSION: Application of the 2010 ESC criteria for ECG interpretation in the athlete improves the accuracy of an ECG-inclusive preparticipation screening strategy by reducing the rate of false positive ECGs.

Significance of electrocardiographic right bundle branch block in trained athletes.

We sought to determine the clinical and physiologic significance of electrocardiographic complete right bundle branch block (CRBBB) and incomplete right bundle branch block (IRBBB) in trained athletes. The 12-lead electrocardiographic and echocardiographic data from 510 competitive athletes were analyzed. Compared to the 51 age-, sport type-, and gender-matched athletes with normal 12-lead electrocardiographic QRS complex duration, the 44 athletes with IRBBB (9%) and 13 with CRBBB (3%) had larger right ventricular (RV) dimensions, as measured by the basal RV end-diastolic diameter (CRBBB 43 ± 3 mm, IRBBB 38 ± 6 mm, normal QRS complex 35 ± 4 mm, p <0.001) and RV end-diastolic area (CRBBB 33 ± 5, IRBBB 27 ± 7, and normal QRS complex 23 ± 3 cm(2); p <0.001). Athletes with CRBBB also had a relative reduction in the RV systolic function at rest as assessed by the RV fractional area change and peak systolic tissue velocity. Finally, QRS prolongation was associated with parallel increases in interventricular dyssynchrony (basal RV to basal lateral left ventricular peak systolic tissue velocity time difference: CRBBB 112 ± 15, IRBBB 73 ± 33, normal QRS complex 43 ± 39 ms, p <0.001). Despite these findings, no athlete with CRBBB or IRBBB was found to have pathologic structural cardiac disease. In conclusion, among trained athletes, CRBBB and IRBBB appear to be markers of a structural and physiological cardiac remodeling triad characterized by RV dilation, a relative reduction in the RV systolic function at rest, and interventricular dyssynchrony.

Cardiovascular screening in college athletes with and without electrocardiography: A cross-sectional study.

BACKGROUND: Although cardiovascular screening is recommended for athletes before participating in sports, the role of 12-lead electrocardiography (ECG) remains uncertain. To date, no prospective data that compare screening with and without ECG have been available. OBJECTIVE: To compare the performance of preparticipation screening limited to medical history and physical examination with a strategy that integrates these with ECG. DESIGN: Cross-sectional comparison of screening strategies. SETTING: University Health Services, Harvard University, Cambridge, Massachusetts. PARTICIPANTS: 510 collegiate athletes who received cardiovascular screening before athletic participation. MEASUREMENTS: Each participant had routine history and examination-limited screening and ECG. They received transthoracic echocardiography (TTE) to detect or exclude cardiac findings with relevance to sports participation. The performance of screening with history and examination only was compared with that of screening that integrated history, examination, and ECG. RESULTS: Cardiac abnormalities with relevance to sports participation risk were observed on TTE in 11 of 510 participants (prevalence, 2.2%). Screening with history and examination alone detected abnormalities in 5 of these 11 athletes (sensitivity, 45.5% [95% CI, 16.8% to 76.2%]; specificity, 94.4% [CI, 92.0% to 96.2%]). Electrocardiography detected 5 additional participants with cardiac abnormalities (for a total of 10 of 11 participants), thereby improving the overall sensitivity of screening to 90.9% (CI, 58.7% to 99.8%). However, including ECG reduced the specificity of screening to 82.7% (CI, 79.1% to 86.0%) and was associated with a false-positive rate of 16.9% (vs. 5.5% for screening with history and examination only). LIMITATION: Definitive conclusions regarding the effect of ECG inclusion on sudden death rates cannot be made. CONCLUSION: Adding ECG to medical history and physical examination improves the overall sensitivity of preparticipation cardiovascular screening in athletes. However, this strategy is associated with an increased rate of false-positive results when current ECG interpretation criteria are used. PRIMARY FUNDING SOURCE: None.

Ability of terminal QRS notching to distinguish benign from malignant electrocardiographic forms of early repolarization.

Recent studies have suggested that early repolarization (ER) might be associated with up to 1/3 of idiopathic ventricular tachycardia/ventricular fibrillation (VT/VF) cases ("malignant" ER). We sought to identify electrocardiographic features to distinguish benign from malignant variants of ER. We reviewed the medical records for implantable-cardioverter defibrillators implanted at a single institution (1988 to 2008) to identify cases of idiopathic VT/VF. The electrocardiograms were scored for ER, defined as a >or=0.1-mV elevation of the QRS-ST junction manifesting as J-point slurring or notching in 2 contiguous leads. We also identified a cohort of 200 healthy age- and gender-matched controls with electrocardiographic findings previously identified as normal ER ("benign" ER cohort). Of 1,224 consecutive implantable-cardioverter defibrillator implants, we identified 39 cases of idiopathic VT/VF. Of the 39 cases, 9 (23%) demonstrated ER. During a mean follow-up of 7.2 +/- 4.6 years, the combined end point of appropriate implantable-cardioverter defibrillator shocks or all-cause mortality occurred less frequently in cases of idiopathic VT/VF with ER than in those without ER (11% vs 30%, odds ratio 0.29, 95% confidence interval 0.03 to 2.69, p = 0.40). A comparison of the electrocardiograms between those with malignant ER and controls demonstrated that QRS notching was significantly more prevalent among cases when present in leads V4 (44% vs 5%, p = 0.001) and V5 (44% vs 8%, p = 0.006), with a similar trend in lead V6 (33% vs 5%, p = 0.013). In conclusion, left precordial terminal QRS notching is more prevalent in malignant variants of ER than in benign cases. These findings could have important implications for risk stratification of patients with ER.