Subsequent ECG Research Articles

A polygenic risk score for the QT interval is an independent predictor of drug-induced QT prolongation.

Drug-induced QT prolongation (diLQTS), and subsequent risk of torsade de pointes, is a major concern with use of many medications, including for non-cardiac conditions. The possibility that genetic risk, in the form of polygenic risk scores (PGS), could be integrated into prediction of risk of diLQTS has great potential, although it is unknown how genetic risk is related to clinical risk factors as might be applied in clinical decision-making. In this study, we examined the PGS for QT interval in 2500 subjects exposed to a known QT-prolonging drug on prolongation of the QT interval over 500ms on subsequent ECG using electronic health record data. We found that the normalized QT PGS was higher in cases than controls (0.212±0.954 vs. -0.0270±1.003, P = 0.0002), with an unadjusted odds ratio of 1.34 (95%CI 1.17-1.53, P<0.001) for association with diLQTS. When included with age and clinical predictors of QT prolongation, we found that the PGS for QT interval provided independent risk prediction for diLQTS, in which the interaction for high-risk diagnosis or with certain high-risk medications (amiodarone, sotalol, and dofetilide) was not significant, indicating that genetic risk did not modify the effect of other risk factors on risk of diLQTS. We found that a high-risk cutoff (QT PGS ≥ 2 standard deviations above mean), but not a low-risk cutoff, was associated with risk of diLQTS after adjustment for clinical factors, and provided one method of integration based on the decision-tree framework. In conclusion, we found that PGS for QT interval is an independent predictor of diLQTS, but that in contrast to existing theories about repolarization reserve as a mechanism of increasing risk, the effect is independent of other clinical risk factors. More work is needed for external validation in clinical decision-making, as well as defining the mechanism through which genes that increase QT interval are associated with risk of diLQTS.

Successful prediction of left bundle branch block-induced cardiomyopathy and treatment effect by artificial intelligence-enabled electrocardiogram.

Left bundle branch block (LBBB) induced cardiomyopathy is an increasingly recognized disease entity. However, no clinical testing has been shown to be able to predict such an occurrence. A 70-year-old male with a prior history of LBBB with preserved ejection fraction (EF) and no other known cardiovascular conditions presented with presyncope, high-grade AV block, and heart failure with reduced EF (36%). His coronary angiogram was negative for any obstructive disease. No other known etiologies for cardiomyopathy were identified. Artificial intelligence-enabled ECGs performed 6 years prior to clinical presentation consistently predicted a high probability (up to 91%) of low EF. The patient successfully underwent left bundle branch area (LBBA) pacing with correction of the underlying LBBB. Subsequent AI ECGs showed a large drop in the probability of low EF immediately after LBBA pacing to 47% and then to 3% 2 months post procedure. His heart failure symptoms markedly improved and EF normalized to 54% at the same time. Artificial intelligence-enabled ECGS may help identify patients who are at risk of developing LBBB-induced cardiomyopathy and predict the response to LBBA pacing.

EYE-ECG: An RCT of the influence of student characteristics and expert eye-tracking videos with cued retrospective reporting on students' ECG interpretation skills.

Teaching of ECG interpretation frequently relies on visual schemas. However, subsequent student ECG interpretation skills are often poor. Expertise research shows that expert looking patterns frequently deviate from the steps taught in schema learning. The present study made a cardiology expert's gaze interpreting ECGs visible - through eye-tracking videos with cued retrospective reporting (CRR) - and investigated the potential as an additional expert-driven route to improve medical students' ECG interpretation skills. N=91 Medical students participated in the RCT of an ECG e-learning session aimed at medical students' ECG interpretation skills gain, either receiving the newly developed eye-tracking video with CRR audio commentary materials (n=47) or studying via four clinical cases only (n=44). Three outcome scores relating to different aspects of ECG interpretation skills were derived from pre-post MCQ ECG tests. The effect of the EYE-ECG training and additional characteristics (e.g., prior experience, interest) on student ECG interpretation skills were evaluated using t-tests and multivariate linear regression. A small, non-significant advantage of the EYE-ECG training signifying a tendency for greater knowledge gain was observed, compared to training as usual. In multivariate regression models, the predictive value of clinical case 1 was an unexpected finding warranting further exploration. Additional gains after an only 9-minute intervention using videos of expert's real-time gaze pattern in combination with hearing their thought processes during ECG interpretation is a promising finding. Furthermore, a number of specific performance characteristics enabling students to best benefit from ECG training were identified and possible modifications to the learning intervention suggested.

P132 A CASE REPORT OF A STEMI MIMICKER IN A PATIENT WITH TUMORAL MYOCARDIAL INFILTRATION AND LITERATURE REVIEW

Abstract Introduction We report a case of ‘STEMI–like’ presentation, with marked STE on ECG in a patient with lung cancer and cardiac catheterization showing no significant coronary obstruction. A 76y woman presented in the emergency room with dyspnea and chest pain.She had a history of hypertension, obesity, previous cerebellar ischemia and pulmonary neoplasia with involvement of left upper lobe and stenosis of main left bronchus and mediastinal infiltration, on palliative treatment.First ECG showed atrial fibrillation (AF) 150 bpm and marked convex STE in I and aVL leads with reciprocal changes, so urgent coronary angiography (CA) was performed. Initial therapy was BB, ASA and UFH. CA surprisingly showed no significant coronary obstruction. Transthoracic echo (TTE) showed a large mass involving pericardium and left atrium, with infiltration of left myocardial lateral wall with a fingernail shape. HS troponin reached 10xN. The STE persisted on subsequent ECGs. In conclusion the ECG changes are due to neoplastic infiltration of left ventricle lateral wall, while AF is due to atrial infiltration. Discharged on day3, the patient was maintained on palliative care plus BB but no antithrombotic therapy due to very high risk of pulmonary bleeding and hemorrhagic infarction of ventricular wall. In our case no Thoracic CT Scan was performed, so we cannot differentiate between cardiac muscular involvement by pericardial metastasis and infiltration by the primary tumor, which is more likely because of the anatomic relationship between left upper lobe and the heart. Discussion Cardiac metastases varies in incidence (2.3 –18.3%), decrease with age, and most frequently origin from respiratory system. They can involve any heart chambers, clinical patterns depend on degree and site of myocardial infiltration.When ventricular wall is infiltrated pseudo–ischemic ECG changes may be induced;persistency of STE suggests tumour compression and/or myocardial infiltration. Patients with known malignancy with chest pain and STE should be screened for cardiac metastases and treated with a single (and not double) antiplatelet agent until coronary stenosis are confirmed. If systemic thrombolysis is considered, a bedside TTE should be performed before therapy.

PO-01-076 DIAGNOSIS OF CORONARY VASOSPASM PROMPTED BY EPISODIC ST ELEVATION ON A CONSUMER MOBILE ECG DEVICE

Mobile ECG-enabled devices are increasingly used by consumers with limited data on sensitivity to detect ischemic ECG changes. Coronary vasospasm is an important cause of sudden cardiac arrest. The aim of this report is to present a case of a man who was determined to have coronary vasospasm resulting in ST elevation and VF. The patient came to medical attention after recording apparent ST elevation on a consumer mobile ECG device. N/A The patient is a 64-year-old man with paroxysmal atrial fibrillation previously treated with catheter ablation with an implantable loop recorder in place. Two weeks prior to his presentation to our institution, he collapsed at church. He was found to be pulseless and underwent bystander CPR. In-field ECG revealed ventricular fibrillation requiring defibrillation (Figure 1A). Subsequent ECG revealed inferior ST elevation. Coronary angiography demonstrated significant stenosis in the left circumflex artery and mild disease in the right coronary artery. Percutaneous coronary intervention of the left circumflex artery was performed with drug eluting stent. The patient was prescribed aspirin, clopidogrel, and metoprolol. Implantable cardioverter defibrillator placement was deferred as his cardiac arrest was felt to be due to an acute coronary syndrome treated with revascularization. Over the subsequent two weeks, the patient reported episodic sensations of chest uneasiness. He recorded a 6 lead ECG on his AliveCor Kardia device at baseline (Figure 1B) and during symptoms (Figure 1C). Exercise treadmill stress testing revealed no evidence of ischemia. Due to ongoing symptoms, he presented to our institution. Baseline ECG was normal. On telemetry, dynamic ST changes were noted with morphology matching the tracing recorded on his Kardia device, followed by degeneration into nonsustained VF (Figure 1D-F). Coronary angiography revealed a patent left circumflex artery stent and stable non-obstructive right coronary artery disease. Echocardiography was normal. Cardiac biomarkers were normal. A diagnosis of coronary vasospasm was made. The patient was managed with amlodipine and isosorbide mononitrate. After an informed discussion, the patient was discharged with a wearable cardioverter defibrillator. He has not had any arrhythmias or ischemic symptoms during follow-up. While typically used to diagnose arrhythmias, mobile ECG monitors may record ischemic electrocardiographic changes. These may assist in the diagnosis of coronary vasospasm.

Detection of Atrial Fibrillation in a Large Population Using Wearable Devices: The Fitbit Heart Study.

Morbidity from undiagnosed atrial fibrillation (AF) may be preventable with early detection. Many consumer wearables contain optical photoplethysmography (PPG) sensors to measure pulse rate. PPG-based software algorithms that detect irregular heart rhythms may identify undiagnosed AF in large populations using wearables, but minimizing false-positive detections is essential. We performed a prospective remote clinical trial to examine a novel PPG-based algorithm for detecting undiagnosed AF from a range of wrist-worn devices. Adults aged ≥22 years in the United States without AF, using compatible wearable Fitbit devices and Android or iOS smartphones, were included. PPG data were analyzed using a novel algorithm that examines overlapping 5-minute pulse windows (tachograms). Eligible participants with an irregular heart rhythm detection (IHRD), defined as 11 consecutive irregular tachograms, were invited to schedule a telehealth visit and were mailed a 1-week ambulatory ECG patch monitor. The primary outcome was the positive predictive value of the first IHRD during ECG patch monitoring for concurrent AF. A total of 455 699 participants enrolled (median age 47 years, 71% female, 73% White) between May 6 and October 1, 2020. IHRDs occurred for 4728 (1%) participants, and 2070 (4%) participants aged ≥65 years during a median of 122 (interquartile range, 110-134) days at risk for an IHRD. Among 1057 participants with an IHRD notification and subsequent analyzable ECG patch monitor, AF was present in 340 (32.2%). Of the 225 participants with another IHRD during ECG patch monitoring, 221 had concurrent AF on the ECG and 4 did not, resulting in an IHRD positive predictive value of 98.2% (95% CI, 95.5%-99.5%). For participants aged ≥65 years, the IHRD positive predictive value was 97.0% (95% CI, 91.4%-99.4%). A novel PPG software algorithm for wearable Fitbit devices exhibited a high positive predictive value for concurrent AF and identified participants likely to have AF on subsequent ECG patch monitoring. Wearable devices may facilitate identifying individuals with undiagnosed AF. URL: https://www. gov; Unique identifier: NCT04380415.

P35 A RARE CASE OF VENTRICULAR ARRHYTHMIA STORM AND COMPLETE ATRIOVENTRICULAR BLOCK IN A PATIENT WITH BECKER MUSCULAR DYSTROPHY

Abstract A 68 year–old male presented to the Emergency Department of our Institute with palpitations for the last 20 minutes. The patient suffered from Becker’s muscular dystrophy (BMD) with hypotonic tetraparesis and dilated cardiomyopathy with moderate left ventricular dysfunction. The patient had also arterial hypertension and a previous ischemic stroke treated with thrombolysis and subsequently with warfarin. On the admission, the patient was alert, blood pressure was 90/60 mmHg and heart rate 180 bpm. An ECG (Fig. 1) showed regular, wide–complex tachycardia (QRS duration of 240 msec) with right branch block morphology with left axial deviation. A bolus of amiodarone 200 mg ev was administered without efficacy followed by a bolus of lidocaine 50 mg. The patient developed symptomatic hypotension, so external electrical cardioversion was performed with a single DC shock at 200J, effective in restoring sinus rhythm. Amiodarone and beta blocker therapy was started. On laboratory tests, the main values were normal, including the ultrasensitive troponin hs–cTnI. Echocardiography showed a mildly dilated left ventricle with diffuse hypokinesia conditioning severe reduction of systolic function (FE 35%) (Fig. 2). On subsequent telemetric ECG monitoring, no recurrences of sustained ventricular tachycardia (VT) were recorded, but it was observed an episode of complete atrioventricular (AV) block conditioning a symptomatic 9.5–second asystole, treated with atropine. Then the patient underwent CRT–D implantation in secondary prevention. The day after the procedure, an arrhythmic storm occurred and was effectively treated with multiple attempts of antitachycardia pacing and device shock. In the following days, the patient continued to present with episodes of VT despite antiarrhythmic drugs. Hence, an endo–epicardial ablation of the arrhythmic substrate was evaluated in Heart team. In view of an intubation and the high anesthesiological risk, it was indicated to continue the optimized medical therapy. Mexiletine 200 mg tid was added to metoprolol 100 mg bid and amiodarone 200 mg od. In the following days, no arrhythmic recurrences were recorded on continuous ECG monitoring. The patient was discharged from the hospital asymptomatic and with no sign of heart failure. At 2 years of follow–up, the patient remained asymptomatic, with no arrhythmic events recorded by the device and in the absence of any adverse effects caused by mexiletine.

Ivabradine Use in a Pediatric Heart Transplant Recipient with Refractory Atrial Tachycardia

<h3>Introduction</h3> Ivabradine, an oral I_f channel antagonist, has been used in pediatric and adult heart failure patients for heart rate control, and in adult heart transplant (HT) recipients with sinus tachycardia secondary to cardiac graft denervation. There are little data describing the use of ivabradine in pediatric HT patients. We describe the use of ivabradine in a pediatric HT recipient with refractory ectopic atrial tachycardia (EAT) causing hemodynamic instability. <h3>Case Report</h3> A 3 year old male underwent HT for restrictive cardiomyopathy. Post-transplant course was complicated by pulmonary hypertensive crisis and cardiac arrest, followed by the development of EAT at a rate of >200 bpm and periods of atrial flutter 2 weeks post-transplant. Steroids were started for suspected clinical rejection, but endomyocardial biopsy was reassuring (ACR grade 1R/1A, pAMR0). Hypotension was noted when EAT rate was >170 bpm. Patient was refractory to esmolol, sotalol, and amiodarone. He underwent EP study with ablation of a posterolateral atrial focus, with recurrence of EAT several hours later. Given ongoing hemodynamic instability with EAT, repeat ablation was performed 1 week later with termination of EAT. However, periodic EAT recurred 3 weeks later and he was again symptomatic with recurrent emesis with rates >170 bpm. Ivabradine 0.05 mg/kg twice daily was initiated. After a single dose, the duration and frequency of EAT periods decreased. Rhythm was mostly sinus (SR) with a rate of 90-100 bpm with premature atrial contractions (PACs), few atrial couplets and blocked PACs. No hypotension, bradycardia, or hemodynamic instability was noted. He was discharged home and dose was up-titrated as an outpatient to 0.2 mg/kg twice daily. Six weeks later, a 72 hour Holter monitor showed predominately SR with short bursts of EAT with variable AV conduction, atrial ectopy overall making up <10% of beats, and rare premature ventricular contractions (PVCs). All subsequent clinic ECGs with follow up to 3 months demonstrated SR. Repeat Holter 3 months after initiation of ivabradine showed SR with rare, isolated PACs and PVCs with no EAT. <h3>Summary</h3> Ivabradine can be considered for EAT treatment in pediatric patients post-HT, with no identified side effects.

533 Uncommon ECG presentation in Tako-tsubo syndrome

Abstract Aims We present the case of an 80-year-old woman without prior cardiovascular history, recent instrumental diagnosis of peritoneal carcinomatosis and ongoing oncologic diagnostic work up. Methods and results The patient was admitted to our ED for acute-onset worsening dyspnoea. On first clinical evaluation, she denied typical angina, remarkable clinical features were dyspnoea, tachycardia and hypotension. Admission ECG showed sinus rhythm with posterior and inferior ST elevation (leads DII, aVF, V5, V6) with reciprocal ST segment depression in leads V1–V2. Echocardiography confirmed infero-postero-lateral akinesia determining moderate reduction of LVEF (35–40%), normal aortic root, no pericardial effusion. Laboratory tests revealed normal WBC count, mild anaemia (HB 10.7 g/dl), normal renal function, elevated C-reactive protein (139 mg/l, n.v. &amp;lt; 8). Cardiac troponin I (cTnI) was normal on admission, with significant delta on second determination (0.012 &amp;gt; 2.5 ng/ml, nv &amp;lt; 0.023). ST elevation persisted after BP normalization and hypoxia treatment; so, taken into account the increased procedural risk due to patient’s age and comorbidities, however we decided to perform urgent coronary angiography. Surprisingly, coronary angiography revealed absence of any significant stenosis, with TIMI 3 flow in any coronary segment. The patient was then admitted to the ICU with diagnosis of MINOCA. The next day ECG revealed normalization of ST segment and Q wave in V2–V3. On day 2 new ECG showed new ventricular repolarization abnormalities with T wave inversion in precordial leads. Peak hs-cTnI was &amp;gt;15 000 ng/l. Repeat echocardiography on day 2 reported complete akinesia of all the apical segments of the LV with normo-hyperkinesia of the mid-basal segments (apical ballooning pattern) and severely depressed systolic function (FE 32–35%). During the following days patient’s symptoms improved, with rapid weaning from oxygen therapy and stable haemodynamic parameters. After 10 days the patient repeated echocardiography, which revealed improvement of global LVEF and persisting mild apical hypokinesia, suggesting the diagnostic hypothesis of Tako-Tsubo Syndrome (TTS) or TTS-phenocopy (unfortunately cardiac MRI was not performed). The patient was therefore transferred to oncology department to complete the diagnostic work-up; primary mammary neoplasia was identified, moreover associated with metastasis in the liver and the brain. Unfortunately, the patient died a month later due to non-cardiac causes. This is the case report of an uncommon MINOCA, which presented mimicking inferolateral acute STEMI, but subsequent ECG and echocardiographic evolution showed the more typical TTS pattern, with apical ballooning on echo and deep negative T waves in anterior leads. Conclusions The prevalence of MINOCA is estimated to be 6% to 8% among patients diagnosed with MI, especially women, however it is more common in patients with NSTEMI compared with STEMI; moreover in cases of TTS presenting with ST elevation, usually the elevation is found in anterior leads without reciprocal ST depression; in this patient instead ST elevation was inferolateral with reciprocal anterior ST depression. Absence of obstructive CAD and clinical/echocardiographic evolution allowed us to confirm the diagnosis of MINOCA/TTS.

Accuracy of Resolution of ST-Segment Elevation in Electrocardiogram to Determine the Patency of Infarct-Related Artery.

Introduction: There is very limited data comparing the accuracy of ECG to angiography in predicting reperfusion status. In this study, we will determine the accuracy of ECG change i.e. resolution of ST-segment elevation in predicting infarct-related artery (IRA) patency after thrombolysis in patients with ST-segment elevated myocardial infarction (STEMI), in comparison to angiography.Methods: Three hundred and forty-one (n = 341) patients with acute STEMI received streptokinase, a thrombolytic agent within 12 hours of symptoms, and were enrolled in the study via consecutive convenient non-probability sampling. ECG was recorded as soon as the patient arrived in the emergency unit of cardiology. Subsequent ECG was recorded three hours after the administration of streptokinase to look for resolution of ST-segment elevation. ST-segment resolution was classified as greater/equal to 50% resolved or less than 50% resolved. Coronary angiography was performed within 24 hours of hospitalization and flow in the IRA was assessed.Results: The most common site of myocardial infarction (MI) was the anterior wall (50.1%) and the commonest artery involved was the left anterior descending artery (44.2%). On ECG, ST-resolution of more than 50% was found in 242 (70.9%) participants. Thrombolysis in MI (TIMI) grade III flow in angiography was found in 211 (61.8%) participants. The sensitivity and specificity of ST-resolution to detect TIMI grade III flow was 94.79% and 67.69%, respectively, while accuracy was 84.46%.Conclusion: ST-resolution on ECG after streptokinase can predict IRA patency on coronary angiography with moderate to good accuracy. ECG can assist in predicting the impact of streptokinase early in the course of management and give an option of monitoring patient prognosis with a non-invasive test in patients not comfortable with angiography.

Abstract 16107: Electrocardiographic Findings and Their Associations With Adverse Outcomes in Hospitalized Patients With COVID-19

Introduction: Although primarily a respiratory illness, COVID-19 frequently involves the cardiovascular system. Hypothesis: Accordingly, we assessed whether abnormal electrocardiographic findings, including cardiac dysrhythmias, ST/T wave changes, and QTc interval prolongation, predict adverse outcomes in patients with COVID-19. Methods: A multi-center retrospective study of hospitalized patients with COVID-19 was performed across 4 hospitals in Texas and 1 in New York. Initial and subsequent ECG findings among patients with uncomplicated disease course, patients with adverse clinical outcomes (need for vasopressors, mechanical ventilation or renal replacement therapy) and patients who died were analyzed. Univariable and multivariable Cox analyses were performed. Results: We identified 297 consecutive patients with COVID-19. Of these patients, 91% had available ECGs. Median heart rate on initial ECG was 92 bpm (IQR: 27), and median QTc interval was 442 msec (IQR: 40). Longer QTc interval on initial ECG was associated with adverse clinical outcomes (443 msec, IQR: 43) and death (457 msec, IQR: 52, vs 441.5 msec, IQR: 36; p=0.033). Cardiac dysrhythmias or ST/T wave changes were noted in subsequent ECGs of 46% of patients and were associated with adverse clinical outcomes (58%) or death (68% vs 33%; HR: 2.2, 95% CI: 1.3-3.6; p=0.002). Sixty-four patients (23%) developed a QTc interval &gt;500msec during their hospitalization. In multivariable Cox analysis, history of coronary artery disease was independently associated with development of QTc&gt;500msec (HR 2.1, 95% CI 1.0-4.4; p=0.047) while other baseline comorbidities were not. Patients with QTc&gt;500msec were more commonly treated with azithromycin (91% vs 77%; p=0.048); no other differences in COVID-19 treatment were identified. In-hospital mortality among patients with QTc&gt;500msec was 37% versus 13% among patients with shorter QTc intervals (HR: 2.6, 95% CI 1.5-4.5; p=0.001). Conclusions: Prolonged QTc interval on initial ECG of COVID-19 patients predicted adverse outcomes and death. Azithromycin was associated with development of QTc&gt;500msec. Patients with a QTc interval &gt;500msec had a 2.6 times higher risk for in-hospital mortality compared to patients with shorter QTc intervals.

The Short QTc Is a Marker for the Development of Atrial Flutter and Atrial Fibrillation.

A short QT interval has been difficult to define, and there is debate whether it exists outside of an extremely small group of individuals with inherited channelopathies and whether it predicts cardiac arrhythmias. The objective was to identify cases with short QT and their consequences. Our hospital ECG database was screened for cases with a QTc based on the Bazett formula (QTcBZT) of less than 340 ms. The QTc was recalculated using the spline (QTcRBK) formula, which more accurately adjusts for the heart rate and identifies cases based on percentile distribution of the QT interval. The exclusion criteria were presence of bundle branch block, arrhythmias, or electronic pacemakers. An age- and sex-matched cohort was obtained from individuals with normal QT intervals with the same exclusion criteria. There were 28 cases with a short QTc (QTcRBK < 380 ms). The age was 69.6 ± 14.6 years (mean ± SD) (50% males). The QT interval was 305.7 ± 61.1 ms with QTcRBK 308.4 ± 31.4 ms. Subsequent ECGs showed atrial flutter in 21%, atrial fibrillation in 18%, and atrial tachycardia in 4% of cases. Thus, atrial arrhythmias occurred in 43% of cases. This incidence was significantly (p < 0.0001) greater than the incidence of atrial arrhythmias in age- and sex-matched controls. In conclusion, a short QT interval can be readily identified based on the first percentile of the new QTc formula. A short QTc is an important marker for the development of atrial arrhythmias, including atrial flutter and atrial fibrillation, with the former predominating. It should be part of patient assessment and warrants consideration to develop strategies for detection and prevention of atrial arrhythmias.

Wide-complex tachycardia in a patient with old myocardial infarction.

An elderly man with a history of coronary artery disease presented with sudden-onset palpitations. The electrocardiogram showed wide complex tachycardia with left bundle branch morphology which terminated spontaneously. Subsequent ECGs confirmed the diagnosis as atrial fibrillation with aberrant conduction because of a diseased left bundle.

P6536Implementation of a mass atrial fibrillation screening program in Canadian community practice

Abstract Background Atrial fibrillation is the most common arrhythmia seen in clinical practice, and is an important cause of stroke. In up to 10% of patients, stroke is the first clinical manifestation of undiagnosed atrial fibrillation (AF). Early detection of AF is therefore desirable, as it would provide an opportunity to initiate appropriate stroke prevention with anticoagulation. While European guidelines recommend screening for AF as part of routine care in patients with risk factors, the optimal modality has not yet been determined. Smartphone enabled single lead ECG devices have been shown to be highly accurate and could prove to be an effective point of care tool for uncovering AF in the community and may facilitate implementation of screening recommendations. Purpose We sought to describe the integration of a smartphone enabled single lead ECG device into the practice of selected Canadian community-based physicians and its impact on patient care. Methods Canadian community-based physicians were provided with a smartphone enabled single lead ECG device for a period of six months. Physicians were instructed to perform a single 30 second ECG recording in patients over the age of 65 who present for a regular follow-up visit. Patients with previous AF diagnosis were excluded. Outcomes related to screening, and stroke prevention-treatment initiation were prospectively ascertained and documented using a patient flow tracker. Results Among 612 physicians who were invited to participate in the program, 315 (51%) agreed to track and report the use of the device that was provided to them. During this program, 315 physicians screened a total of 15,538 patients. AF was detected 1103 patients (7.1%). The majority of patients with a positive screen underwent a subsequent 12-lead ECG confirmatory exam (79%). AF could not be confirmed in 277 patients (31.7% of patients undergoing 12-lead ECG). A total of 677 patients were initiated on oral anticoagulation (OAC), with 262 patients (24%) being initiated on OAC prior to ECG confirmation. Conclusion Undiagnosed AF is common in patients &gt;65 years of age in community practice. The results of this program indicate that single lead mobile ECG devices can be integrated into routine point of care use for Canadian physicians and, can be a valuable tool to detect previously undiagnosed AF. While this approach identified a large number of undiagnosed AF patients eligible for OAC therapy, undertreatment with OAC remains a concern. Acknowledgement/Funding Bristol-Myers Squibb/Pfizer Alliance

Rationale and design of a large-scale, app-based study to identify cardiac arrhythmias using a smartwatch: The Apple Heart Study

BackgroundSmartwatch and fitness band wearable consumer electronics can passively measure pulse rate from the wrist using photoplethysmography (PPG). Identification of pulse irregularity or variability from these data has the potential to identify atrial fibrillation or atrial flutter (AF, collectively). The rapidly expanding consumer base of these devices allows for detection of undiagnosed AF at scale.MethodsThe Apple Heart Study is a prospective, single arm pragmatic study that has enrolled 419,093 participants (NCT03335800). The primary objective is to measure the proportion of participants with an irregular pulse detected by the Apple Watch (Apple Inc, Cupertino, CA) with AF on subsequent ambulatory ECG patch monitoring. The secondary objectives are to: 1) characterize the concordance of pulse irregularity notification episodes from the Apple Watch with simultaneously recorded ambulatory ECGs; 2) estimate the rate of initial contact with a health care provider within 3 months after notification of pulse irregularity. The study is conducted virtually, with screening, consent and data collection performed electronically from within an accompanying smartphone app. Study visits are performed by telehealth study physicians via video chat through the app, and ambulatory ECG patches are mailed to the participants.ConclusionsThe results of this trial will provide initial evidence for the ability of a smartwatch algorithm to identify pulse irregularity and variability which may reflect previously unknown AF. The Apple Heart Study will help provide a foundation for how wearable technology can inform the clinical approach to AF identification and screening. (Am Heart J 2019;207:66–75.)

Abstract P027: Time-updated Premature Ventricular Contractions on 12-lead ECG Are Associated With the Risk of Sudden Cardiac Death: Atherosclerosis Risk in Communities Study and Cardiovascular Health Study

Introduction: The association between premature ventricular contractions (PVCs) and Sudden Cardiac Death (SCD) remains controversial. Hypothesis: We hypothesized that PVCs are associated with SCD. Methods: Presence of PVCs was detected on 12-lead ECG recorded at baseline or any of 4 follow-up visits in 15,667 participants (pts) (mean age: 54.2 + 5.8 Yrs; 55% female; 73% Whites) of the Atherosclerosis Risk in Communities (ARIC) study. For validation cohort, we included baseline and 9 follow-up visits ECG data in 5,846 pts (mean age: 72.8+ 5.6 yrs; 57.7% female, 84.2% whites) from Cardiovascular Health Study (CHS). Competing risk analyses models were constructed to test the association between time-updated PVCs and SCD risk. Model 1 was adjusted for age, sex, race and study center. Model 2 in addition was adjusted for time-updated coronary heart disease, heart failure, atrial fibrillation, stroke, and hypertension. Results: In ARIC pts, across all study visits, PVCs were observed in 2.6% of the ECGs; 99.7% of pts were PVC-free at least once; 8.8% of pts had PVC at least once. 97.7% of pts without PVCs remained PVC-free at the next visit; 19.1% of pts with detected PVC had PVC at the next visit; 2.4% of pts who were PVC-free on previous ECG, transitioned to having PVC on subsequent visit ECG. In CHS, across all 10 yearly study visits, on average, PVC was observed on 4.85% of ECG recordings; 99.4% of participants were PVC-free at least once; 21.9% of pts had PVC at least once. 96.4% of PVC-free pts remained free from PVC at the next visit. 30.6% of pts with detected PVC on a given ECG had PVC at the next visit. 3.6% of pts who did not have PVC on previous ECG, transitioned to having PVC at the next visit. 69.4% of pts with PVC on a given ECG transitioned to being PVC-free next year. In adjusted competing risk analysis PVC was associated with SCD, but not with non-sudden cardiac death or non-cardiac death (Table). Conclusions: Time-updated presence of PVC on a short 10-sec resting 12-lead ECG is associated with SCD.

The subsequent ECG synchronized CT scan shows no evidence of dissection

The subsequent ECG synchronized CT scan shows no evidence of dissection

Фибрилляции предсердий у пациентов с ожирением в практике терапевта

We examined 296 patients with atrial fibrillation and arterial hypertension consisting of a collection of complaints, anamnesis, and objective examination, measurement of waist circumference (WS), the study of leptin levels in blood of the patients with BMI 25 kg/m 2 or more at the beginning of the observation, electrocardiographic examination (ECG), echocardiography at the beginning and at the end of the study. Paroxysms of atrial fibrillation were recorded when performing ECG in case of occurrence of symptoms typical for AF, but asymptomatic forms were detected by daily monitoring the regularity of the radial pulse with the subsequent ECG to confirm AF. A patient should be observed for a year. Overweight and abdominal obesity affect the course of atrial fibrillation, increasing the number of repeated paroxysms. Predictors of repeated paroxysms of atrial fibrillation were women with WS more than 80 cm, the hormone content above 8.7 mg/ml and diastolic blood pressure over 90 mmHg and men with BMI 25 kg/m 2 or more.

Cope's sign and complete heart block in a 78-year-old patient with biliary colic

IntroductionAcute cholecystitis and biliary colic may have signs and symptoms similar to those of Acute Coronary Syndrome(ACS) along with ischemic ECG changes. Cholecystitis and/or biliary colic have been both reported as trigger factors for bradyarrhythmia in the literature. Case ReportA 78-year-old male patient was admitted to our Emergency Department (ED) due to acute abdominal pain. The ECG on admission showed sinus bradycardia with a rate of 40 beats per minute (bpm) without signs of acute ischemia and a brief period (7 s) of complete atrioventricular (AV) block. He was initially treated with analgesics. After the remission of the pain, a subsequent ECG was performed which showed sinus bradycardia of 55 bpm. The AV block terminated one hour after the patient’s admission. The patient remained hemodynamically stable during the episode. He underwent an ultrasound of the abdomen in the ED which revealed sludge and one stone in the gallbladder without signs of inflammation. Laboratory test results for D-dimer and troponin were negative, while the coronary angiography showed coronary vessels without significant lesions. ConclusionBiliary colic can cause severe reversible reflex bradycardia (Cope’s Sign), even complete heart block. Pain relief is very important in the management of such cases.

Football Athlete with Chest Pain and Dysphagia

HISTORY: 22 year old collegiate football player was seen in clinic for several years of intermittent dysphagia with associated chest pain. Symptoms had occurred 3-4 times annually, but athlete had noted increasing frequency over the past several weeks with occasional associated heartburn. He was initially treated with oral omeprazole 40 mg daily for presumed gastroesophageal reflux disorder. Two weeks later, following an intense practice, he developed severe, burning, substernal chest pain and diaphoresis which prompted emergency department evaluation for possible cardiac etiology. PHYSICAL EXAMINATION: Vitals: HR 56, BP 147/90, RR 18 General: Uncomfortable, writhing on exam table Neck: Supple. No lymphadenopathy. CV: Regular rate and regular rhythm with no murmurs. No friction rub heard. Distal pulses are intact. No lower extremity edema. Pulmonary: No respiratory distress. Lungs are clear to auscultation bilaterally. Abdominal: Soft, non-tender, non-distended. DIFFERENTIAL DIAGNOSIS: GERD Esophageal stricture Esophageal spasm Acute coronary syndrome Myocarditis/Pericarditis Coronary or aortic dissection TESTS AND RESULTS: WBC 5.5, HGB 13.7 Troponins- 0.09, 0.24, 3.63 (peak) CRP 0.2, ESR 9 Creatinine 1.8 CK (peak) 836 ECG: interpreted as having diffuse ST elevation Subsequent ECG: precordial J point elevation without concave ST elevations Echocardiogram: left ventricular ejection fraction of 45-50% Cardiac MRI: Small areas of focal mid-wall, late gadolinium enhancement (LGE) consistent with myocarditis Barium swallow study: transient “feline esophagus” without diverticulum or stricture EGD: longitudinal furrows with punctate white spots. Biopsies revealed increased intra-epithelial eosinophils up to 50 per hpf TSH 1.06 ANA, ANCA, Anti-SCL 70, C4 all negative FINAL WORKING DIAGNOSIS: Presumptive Viral Myocarditis Eosinophilic Esophagitis (EoE), biopsy-proven TREATMENT AND OUTCOMES: Placed on medical hold for remainder of football season Repeat cardiac MRI improved Returned to light weightlifting and easy spinning without recurrence of symptoms. Will be reevaluated by exercise stress test and echocardiogram before further return to sport decisions are made Remains on twice daily omeprazole 40 mg for management of his EoE until follow up with GI.