Optimal method for ablation of atypical AVNRT.

BACKGROUND: Considering that ablation of atypical AVNRT may be unsuccessful after ablation at the right posterior septum, in this study, we aimed to present an optimal method for ablation of atypical AVNRT. Also, we evaluated the efficacy of this technique for preventing recurrences. METHODS: This is a prospective, double-center study. It was conducted on 62 patients with atypical AVNRT referred for radiofrequency ablation. The patients were randomly divided into two groups before ablation: 1-Group A (n = 30): treated with conventional ablation at the anatomic area of the slow pathway; 2-Group B (n = 32): ablation was done 2 mm higher in the septum during fluoroscopy. RESULTS: The mean age of patients in groups A and B were 54 ± 11.7 and 55 ± 12.2, respectively (P = 0.43). In group A, ablation was successful in 24 (80%) patients following right-sided slow pathway ablation, and the remaining patients required further treatment with either a left-side approach (N = 4, 13.3%) or ablation of additional regions (N = 2, 6.7%). In group B, ablation was successful in all patients. After a 48-month follow-up, recurrence of symptomatic atypical AVNRT was detected in 4 (13.3%) patients of group A and none of group B patients (p < 0.001). CONCLUSION: In patients with atypical AVNRT, ablation 2 mm above the conventional area is more promising regarding success rate and recurrence of the arrhythmia.

Evaluation of the efficacy of signal-averaged electrocardiogram testing in the cardiac assessment of beta-thalassemia major patients.

BACKGROUND: More than 70% of thalassemia's major mortality is due to the cardiac complications of this syndrome, mostly consequent to myocardial Iron overload; therefore, evaluation of such complications is of utmost importance. T2*MRI is used to assess hepatic and myocardial Iron load in thalassemia patients, which is not always available. Signal-Averaged Electrocardiography is a rather easy method of evaluating major thalassemia patients regarding their risk for sudden cardiac death. METHODS AND MATERIALS: In this cross-sectional study, 48 patients with thalassemia major underwent evaluation with electrocardiography, signal-averaged electrocardiography, echocardiography, T2*MRI, and ferritin level. The association of the existence of ventricular late potentials in SAECG and other cardiac variables was evaluated. Moreover, the association between myocardial and hepatic Iron load and cardiac characteristics was assessed. RESULTS: 48 patients with a mean age of 30.31 ± 7.22 years old entered the study. 27 (56.3%) of the patients had ventricular late potentials, which were associated with myocardial dry Iron weight (P = 0.011). Nonspecific ST-T changes and premature atrial and ventricular contractions were seen more frequently in patients with late potentials (P = 0.002, 0.031, and 0.031, respectively). Patients with higher myocardial and hepatic Iron loads had longer QTc in their 12-lead surface electrocardiograms. CONCLUSION: Patients with ventricular late potentials assessed by SAECG had a higher myocardial Iron load. Higher myocardial Iron load is associated with higher cardiac complications in patients with beta-thalassemia major; therefore, SAECG can be used as a screening test for cardiac complications in beta-thalassemia major patients.

Body Image and Adjustment among Patients with Heart Rhythm Management Devices following Cardiac Rehabilitation Program: A Randomized, Controlled Clinical Trial.

Introduction: Heart rhythm management devices save patients' lives. However, they may cause problems with the patient's perspective of their body image. Therefore, given the significance of the heart function and cardiac rehabilitation, this study was conducted to investigate and compare the effect of the cardiac rehabilitation program on adjustment and body image among patients who use heart rhythm management devices.Methods: This two-group clinical trial was conducted with 100 patients who used various heart rhythm management devices. The patients were randomly assigned into either the control group or intervention group (50 patients in each group) via four triad blocks. The intervention was 16 sessions of the cardiac rehabilitation program and 4 telephone follow-ups over twelve weeks. Data was gathered before the intervention and both eight and twelve weeks after the intervention using the psychosocial adjustment to illness scale and the body image and relationships scale.Findings: The majority of the patients were male and in the age range of 40-60 years. Before the intervention, no statistically significant differences were reported between the groups in terms of adjustment control = 68.13 ± 9.1, intervention = 67.13 ± 4.6) and body image (control = 93.14 ± 8.5, intervention = 91.16 ± 8.4) (P>0.5). However, in the intervention group, with each of three devices (pacemaker, ICD, CRT), significant improvements were observed in all aspects of adjustment (16.7 ± 9.3, 25.3 ± 9.5, 20.6 ± 10.3) and body image (45.50 ± 9.80, 55.10 ± 8.80, 42.90 ± 6.10) over time respectively (P<0.001).Conclusion: The effectiveness of the cardiac rehabilitation program in improving the body image was reported in this study. Therefore, the cardiac rehabilitation program can have a vital role in improving body image and adjustment among patients who use various cardiac rhythm management devices.

Significance of ST-Segment elevation in V4R lead in patients with anterior myocardial infarction.

BACKGROUND: There is some evidence of the association between ST-segment elevation in the V4R chest lead and the likelihood of anterior wall myocardial infarction; however, the link of this phenomenon with the location and the severity of the coronary involvements in such patients remains uncertain. We aimed to investigate the ST-segment elevation in V4R leads in patients with anterior myocardial infarction and also its effect on prognosis as well as the detection and prediction of the location of arterial stenosis in coronary angiography. METHODS: Data collection was performed by reviewing the hospital recorded files of 195 patients' suspicion of acute myocardial infarction who have been referred within 2 h of the onset of cardiac symptoms. The patients were then categorized into two groups with and without ST elevation in the V4R chest lead. RESULTS: Comparing two groups showed a significantly higher rate of concurrent ST-segment elevation in V1 lead in those with ST-segment elevation in V4R. Echocardiography on the day after anterior myocardial infarction showed LVEF <40% in 74% and 35.2% of patients with and without ST-segment elevation in V4R, respectively, indicating a significant difference. The lesions on proximal LAD were more common in the group with ST-segment elevation in V4R. CONCLUSION: Our study emphasized a high likelihood of ST-segment elevation in V4R lead concurrently with ST-elevation in V1 lead. Also, the appearance of ST-segment elevation in V4R lead can be accompanied with a lower LVEF, myocardial infarct size, involvement of proximal part of LAD, and Wrap around LAD.

Prevention of adhesive capsulitis following pacemaker implantation: A randomized controlled study.

INTRODUCTION: Gradual painful loss of active and passive range of motion in shoulder joint was introduced as adhesive capsulitis (AC). Disabilities in patients with AC are absenteeism from work, loss to leisure time, and recurrent seeking to health care services. The aim of this study was to evaluate the incidence of AC following pacemaker implementation. The effect of physical therapy and exercise education was also evaluated to prevent AC following pacemaker implementation. METHODS: This study is a randomized clinical controlled trial. It was conducted on 62 pacemaker candidates. Patients with no shoulder pain and without any motion limits were enrolled in the study consecutively. The patients randomly were divided into two groups after pacemaker implementation. One group was treated with physical therapy (group A, n = 28) and the other group did not (group B, n = 34). The incidence of AC was assessed in both groups after 4 months. RESULTS: A total of 62 patients were enrolled in the study. The mean age was 63.2 ± 12.1 years in the group A and 67.1 ± 17.6 years in the group B. Age was not significantly different between groups. A total of 11 patients (17.7%) had AC 16 weeks after the initial visit (two patients in group A and nine patients in group B; P = .004). CONCLUSIONS: Incidence of AC is 17.7% following device implantation. Exercise education and physical therapy significantly reduces AC incidence following pacemaker implantation.

Effect of Cardiac Resynchronisation Therapy on Electrical Remodelling.

BACKGROUND: Cardiac resynchronisation therapy (CRT) is an accepted device therapy in patients with low ejection fraction. Beneficial effects of CRT result from mechanical remodelling. Some controversial reports suggest that CRT may also induce electrical remodelling with intrinsic QRS narrowing but still the effect of CRT on electrical remodelling is an issue for debate. The aim of our study was to evaluate the effects of CRT on intrinsic QRS duration. For clarity, our analysis was performed by the signal averaged electrocardiogram (SAECG) which is a high resolution electrocardiographic signal suitable for accurate measurement of QRS duration. Signal averaged electrocardiogram provides a better value of QRS duration compared to 12-lead ECG by the ability to detect ventricular late potentials. METHODS: A total of 48 consecutive patients with severe systolic dysfunction and typical left bundle branch block (LBBB) were enrolled in the study prospectively. Patients were scheduled for CRT-D implantation according to the current guidelines. Intrinsic QRS duration was accurately measured by SAECG before and at least 14 months after CRT implantation. RESULTS: The mean intrinsic QRS duration remained unchanged during follow-up (from 149.9±13.8ms to 149.6±18.4ms; P= 0.3). Among 32 CRT responder patients, the mean intrinsic QRS duration remained unchanged during follow-up. Also, the mean intrinsic QRS duration showed no significant changes in 16 CRT non-responders. CONCLUSION: Structural remodelling induced by CRT does not necessarily translate into decrease of intrinsic ventricular activation. Despite significant left ventricular recovery, electrical characteristics of the left ventricular conduction system cannot generally be expected to recuperate.

Prediction of midterm performance of active-fixation leads using current of injury.

BACKGROUND: There are only limited prospective data on the clinical relevance of current of injury (COI) as a predictor of the midterm performance of active-fixation leads. This study sought to investigate whether it is possible to predict the midterm performance of active-fixation leads using COI recorded at the time of implantation. METHODS AND RESULTS: One hundred fifty patients (78 men; mean age, 63 ± 19 years) who received active-fixation pacing (n = 201) and defibrillator (n = 51) leads were studied. COI was measured from the intracardiac bipolar electrogram recorded at the time of lead implantation. The study outcome was good lead performance at 6 months, defined as P wave ≥ 1.5 mV, threshold <1.5 V for atrial lead, R-wave ≥ 5 mV, and threshold <1 V for ventricular lead. A total of 102 active-fixation atrial and 150 ventricular leads were implanted. During a 6-month follow-up, invasive intervention was required for seven atrial and seven ventricular leads. In multivariate analysis, COI was the only independent predictor of good outcome for the active-fixation atrial (odds ratio [OR]: 5.67, 95% confidence interval [CI]: 2.18-14.76, P = 0.001) and ventricular leads (OR: 3.99, 95% CI: 1.08-21.26, P = 0.002). Receiver-operating characteristic analysis identified ST-segment elevation ≥2.0 mV for the atrial leads (sensitivity, 75%; specificity, 89%) and ≥10.0 mV for the ventricular leads (sensitivity, 70%; specificity, 87%) as optimal cutoffs for good midterm performance. CONCLUSIONS: Midterm performance of active-fixation leads is predictable using COI recorded at the time of lead implantation. A ST-segment elevation ≥2.0 mV in the atrial leads and ≥10.0 mV in the ventricular leads are recommended to improve the lead performance at 6 months.

Catheter ablation of an accessory pathway within the marshall vein in a patient with mechanical mitral valve.

A 37-year-old man, known case of mitral valve replacement, was referred for ablation. Meticulous mapping showed the earliest signal in the distal coronary sinus (CS). Endocardial ablation via transseptal approach failed to permanently ablate the accessory pathway. Similarly, ablation within the CS was unsuccessful. Finally, the mapping catheter was introduced into the vein of Marshall (VoM) and a very early signal was obtained. In the first 3 seconds of the radiofrequency energy application within the VoM, delta wave disappeared. During 1-year follow-up, the patient had no recurrence of the palpitations and electrocardiogram showed no delta wave.

Positive Brugada challenge test in V1 R-V3 R as a predictor of malignant prognosis in Brugada patients.

BACKGROUND: The Brugada syndrome is a heterogeneous genetic disease that predisposes to life-threatening ventricular tachyarrhythmias and sudden cardiac death (SCD). The only proven way to prolong the survival of patients with Brugada syndrome is to implant an implantable cardioverter-defibrillator (ICD). This should be implanted for high-risk patients only. METHOD: The patients with type 2 or 3 Brugada ECG pattern were selected for the study. We evaluated 126 patients with Brugada type ECG patterns. Nineteen patients had positive response. Those who had positive result in right side located leads had poorer prognosis. CONCLUSION: Positive flecainide challenge test in right side located pericordial leads can be used as a predictor of poor prognosis in Brugada patients. This can be evaluated in another research for its role in the implantation of ICD. Also, the oral flecainide is not sensitive enough to rule out the presence of Brugada syndrome and it should not be trusted as a screening test for suspected cases.

The effect of left ventricular (LV) remodeling on ventricular arrhythmia in cardiac resynchronization therapy (CRT-D) patients (antiarrhythmic effect of CRT).

BACKGROUND: In patients with low ejection fraction and ventricular dyssynchrony, cardiac resynchronization therapy (CRT) is an accepted therapeutic modality. In these patients, CRT can improve the quality of life and exercise tolerance in addition to improved survival. On the other hand, antiarrhythmic effects of CRT is a place of debate. METHOD: In this study, we evaluated the effect of CRT-induced reverse remodeling on ventricular arrhythmia in heart failure patients. Patients with CRT were divided to two groups of responders and nonresponders. Responders were those with reduction of LVESD of more than 10% or increase in LVEF of more than 5%. They were visited and device analysis was performed during the follow-up. RESULTS: One hundred and nineteen patients were enrolled in this study. Those with reverse remodeling experienced fewer ventricular arrhythmias after two years of follow-up (N = 2 vs 11, P = 0.001). CONCLUSION: Reverse remodeling associated with CRT implantation can result in decreased frequency of ventricular arrhythmias.

A Novel Technique for Managing Guidewire-Induced Distal Coronary Perforation Using Coronary Balloon Pieces.

We report the case of a 49-year-old female patient who underwent percutaneous coronary intervention of the right coronary and posterior descending arteries complicated with guidewire-induced coronary artery perforation. We successfully managed and sealed this perforation through the embolization of balloon pieces into the target vessel. (Level of Difficulty: Advanced.).

Comparing Clinical and Hemodynamic Parameters between the Two Aortic Valve Replacement in Patients with Severe Aortic Stenosis.

Context: Various techniques have been proposed for suturing following prosthetic aortic valve implantation, but each has its potential side effects such as patient-prosthesis mismatch (PPM) and paravalvular leak (PVL). Aims: In the present study, we aimed to compare the postoperative sequels of aortic valve replacement (AVR) following the use of two suturing techniques including from the inside of the aorta as the common and classic suturing techniques as compared to new approach including from the outside of the aorta. Settings and Design: This cross-sectional study was performed on patients suffering from symptomatic severe aortic valve disease and candidates for AVR in one of three referral hospitals for cardiovascular disease patients in Shiraz from 2019-2021. Subjects and Methods: The patients underwent one of the two considered surgical techniques for AVR including traditional approach (n = 60) or the tested approach (suturing from the outside of the aorta) (n = 30). Statistical Analysis Used: For statistical analysis, results were presented as mean ± standard deviation for quantitative variables and were summarized by frequency (percentage) for categorical variables. Results: PVL and PPM were revealed in none of the participants undergoing the tested approach, while the pointed complications were found in 41.7% and 25.0% of patients underwent traditional approach, respectively, indicating a significant difference. There was no evidence of abnormal dimensionless valve index (DVI) in the patients undergoing sutures from outside the aorta, whereas the rate of DVI abnormality in the patients undergoing traditional procedures was shown to be 18.3%. The mean aortic valve gradient was significantly higher in the group scheduling for the traditional surgical method. Conclusions: Applying new suturing method as suturing from the outside of the aorta, due to the selection of appropriate valve size, the risk for adverse consequences including PPM, PVL, or DVI can be significantly reduced.

The value of QRS onset of the outflow tract PVC in V1 and V2 leads recorded in fourth, third, and second intercostal spaces to differentiate main origins of premature ventricular contraction-A prospective cohort study.

Background: Electrocardiography (ECG) is now proposed as a simple and cost-effective tool to determine the location of arrhythmias before ablation. We aimed to examine the value of the QRS onset of outflow tract PVC in V1 and V2 leads recorded in fourth, third, and second intercostal spaces to differentiate two main origins for premature ventricular contraction (PVC) including right ventricular outflow tract (RVOT) and left ventricular outflow tract (LVOT). Methods: In this prospective cohort study, a total of 58 patients were studied, from whom a surface ECG was obtained using V1 and V2 leads in the fourth, third, and second intercostal spaces. ECG and Electrophysiology studie (EPS) data were then recorded and compared to determine the sensitivity and specificity of QRS onset in locating arrhythmias. The reciever operating characterictic (ROC) curve analysis was applied to test diagnostic performance. Results: Based on the time of PVC initiation in each of the V1 and V2 leads in the fourth intercostal space, if PVC is recorded earlier in the V1 lead, its source in 95.8% of the patients is RVOT and if PVC preceded the V2 lead, 70.59% of the patients had PVC from LVOT. Comparing of QRS onset in V1 and V2 leadsrecorded from third% and and second intercostal spaces had considerable sensitivity and specificity to determine the origin of the outflow tract PVC (81.82 and 94.12%, respectively). Conclusion: Simultaneous recording of outflow tract PVCs from second third and fourth intercostal spaces and comparing their onset can determine the left and right outflow tract PVCs with high sensitivity and specificity.

Signal averaged ECG in patients with early repolarization.

BACKGROUND: Early repolarization (ER) pattern is diagnosed when the J-point is elevated on the patient's electrocardiogram. The aim of this study was to evaluate signal-averaged electrocardiography (SAECG) in patients with ER pattern. METHODS: Subjects were divided into three groups: 1-patients with normal ECG pattern (control group); 2-patients with J-point elevation in the inferior leads; and 3-patients with J-point elevation in non-inferior leads. RESULTS: The mean filtered QRS duration in groups with J-point elevation in inferior leads and non-inferior leads and in the control, was 86.4 ± 23.4 msec, 84.8 ± 26.6 msec, and 85.8 ± 24.8 msec, respectively, indicating no significant difference across the three groups. The mean duration of terminal QRS < 40µV was 21.2 ± 4.2 msec, 22.8 ± 4.6 msec, and 23.1 ± 4.5 msec in the mentioned groups, respectively, without a significant difference between the groups. Additionally, the mean root-mean-square voltage of terminal 40 msec was 34.5 ± 8.3 µV, 35.3 ± 8.6µV, and 35.7 ± 9.2 µV in patients with increased J-point in inferior leads, non-inferior leads, and the control group, respectively, showing no difference between the groups. CONCLUSION: In conclusion, we found that parameters in SAECG did not have any significant difference between patients with ER pattern and healthy individuals. Moreover, we concluded that SAECG cannot distinguish the patients with elevated J-point in inferior leads from non-inferior leads. Overall, SAECG does not appear to be a reliable diagnostic tool for the assessment of ER pattern.

aVR ST-segment changes and prognosis of ST-segment elevation myocardial infarction.

BACKGROUND: Clinical importance of aVR lead-related changes in predicting the prognosis of acute myocardial infarction remains uncertain. The present study aimed to assess the value of ST-segment changes in aVR lead and the outcome and sequels of the first episode of acute ST-segment elevation myocardial infarction. METHODS: This prospective cohort study was conducted on patients suffering first episode of ST-segment elevation myocardial infarction and underwent percutaneous coronary intervention. Information was collected through hospital-recorded files reading. The electrocardiogram (ECG) was taken from the patients upon entering the hospital and followed-up for 30 days to assess cardiovascular complications. RESULTS: In patients with anterior STEMI, with the use of multivariate analysis, admission aVR ST elevation ≥1 mm was found to be a strong and independent predictor of major cardiovascular adverse events (MACE) within 30 days of discharging (P value for trend .002). In patients with inferior (± RV) ST-segment elevation myocardial infarction (STEMI), with the use of multivariate analysis, admission aVR ST depression ≥1 mm was found to be a strong and independent predictor of MACE within 30 days of discharging (P value for trend .01). CONCLUSION: In patients with anterior STEMI, admission aVR STE ≥1 mm was found to be a strong and independent predictor of MACE within 30 days of discharging. On the other hand, in patients with inferior STEMI, aVR ST depression ≥1 mm was found to be a strong and independent predictor of MACE within 30 days of discharging.

Uncovering Cardiac Involvement in Childhood Diabetes: Is it Time to Move Toward Speckle Tracking Echocardiography in Childhood Diabetes Management?

CONTEXT: One of the most common endocrine disorders in children is diabetes which is the leading cause of premature cardiovascular disease in adulthood. AIMS: This study is aimed to investigate the extend of cardiac involvement in diabetic children by speckle tracking echocardiography (STE) in comparison to two-dimensional (2D) echocardiography and routine laboratory data. SETTINGS AND DESIGN: A cross-sectional study conducted on patients under 18 years of age who deal with type one diabetes mellitus for more than 5 years. SUBJECTS AND METHODS: To compare the STE results, we included the STE data of 25 normal age-matched children. All patients underwent laboratory analysis for lipid profile, blood sugar, and 2D echocardiography plus STE. STATISTICAL ANALYSIS USED: Two-sample independent t-test, Chi-square test, logistic regression test, Spearman's rank correlation coefficient, and the Pearson correlation coefficient. RESULTS: From March 2018 to 2019, we included 53 patients, mean age 15.8 ± 0.39 years and 52.8% female, and 25 nondiabetic control in this study. STE revealed global longitudinal strain (LS) -18.4 versus - 24.2 for patient (44 valid cases) versus control group, respectively, with significant statistical difference. Diabetic patients had lower LS in all segments compared to the control group. CONCLUSIONS: STE has very high sensitivity to detect cardiac involvement far earlier than 2D echocardiography. None of the routine biomarkers or demographic features can predict cardiac involvement based on segmental abnormalities of STE. Active investigation to clear the remote impact of STE abnormalities and its practical role in childhood diabetes management is highly recommended.

Aortopathic effect of androgenic anabolic steroids.

BACKGROUND: Anabolic androgens have been reported to be associated with cardiovascular complications. One study revealed that increase in vascular stiffness in bodybuilders is associated with anabolic androgens and improvement in vascular function may occur following anabolic androgens discontinuation. The aim of this study was to investigate any possible relation between aortic elastic properties and anabolic androgens. METHODS: Study population was divided into 3 groups: Group-1 [n = 35] consisted of bodybuilders who denied any current or previous use of anabolic androgens. Group-2 [n = 18] was bodybuilders with regular using of anabolic androgens for at least 2 year prior to the start of our study. Group-3 was 13 healthy age-matched sedentary men as a control group. Cardiac echocardiography was performed in the bodybuilders and controls and indexes of aortic function were calculated. RESULTS: Aortic stiffness was approximately twofold higher in anabolic androgens user bodybuilders compared with drug-free bodybuilders [P < 0.001]. CONCLUSION: The present study demonstrates that chronic anabolic androgens use clearly produces significant decrease in the elastic properties of aorta.

Negative current of injury due to inadvertent polarity reversal during active atrial lead implantation.

We report an example of the negative current of injury (COI) during permanent pacemaker implantation. Cardiac perforation was our first priority. However, patient had stable hemodynamics, and the fluoroscopic location of the atrial lead was acceptable. Therefore, the connections were checked revealing the cause of the negative COI; the red (+) clips was attached to the tip of the atrial lead rather than anodal ring. Correcting the connections resolved the problem. This report shows that a negative COI might not only be due to cardiac perforation or right ventricular ischemia but that checking the lead connectivity should be carried out first.

Balloon-shaped cystic subaortic membrane.

A 22-year-old man with a 4 month history of dyspnoea on exertion was referred for echocardiography. Transthoracic echocardiography revealed a balloon-shaped cystic mass (2 x 2 cm) attached to the left ventricular outflow tract (LVOT). Continuous-wave Doppler echocardiography showed a 44 mmHg mean LVOT gradient. The patient underwent transoesophageal echocardiography for detailed echocardiographic examination of LVOT and aortic valve. Transoesophageal echocardiography revealed a balloon-shaped cystic mass originating from the LVOT at the aorto-mitral communication. In the operating theatre, a cystic ballooning subaortic membrane was found and excised successfully. The morphology of the membrane was similar to that shown by transoesophageal echocardiography.

Short QT interval: A novel predictor of androgen abuse in strength trained athletes.

OBJECTIVES: To find the relationship between anabolic androgenic steroids (AAS) using and QT interval in athletes. METHODS: Between January 1, 2005 and May 31, 2007, we examined QTc interval duration in 165 consecutive male professional bodybuilders [age: 32.1 +/- 4.6 years]. Of these, 79 were AAS users. The control group included 90 sedentary age and gender matched subjects [none of them were AAS users]. RESULTS: The QTc interval of AAS abusing bodybuilders was significantly shorter compared with QTc interval in AAS-free bodybuilders and control group. Short QTc interval (< or =380 ms) was an independent predictor of AAS abusing in the multivariate analysis. CONCLUSIONS: To the best of our knowledge, there is no published report regarding electrocardiographic diagnosis and screening of AAS abusing athletes. In the present study, we present an easy and applicable method to screen and diagnose AAS abusing among professional bodybuilders. In the presence of QTc interval < or = 380 ms in a bodybuilder, one would predict AAS abusing with 83% sensitivity and 88% specificity.