Lead aVL Research Articles

A LABILE EQUILIBRIUM: THE CONTROVERSIAL ROLE OF BETA–BLOCKERS IN A CASE OF MID–VENTRICULAR TAKOTSUBO SYNDROME

Abstract Case Report Takotsubo syndrome (TTS) is a non–ischemic heart disease mimicking acute coronary syndrome. The mid–ventricular variant is almost rare (15% of TTS cases). A 62 years old woman was referred to our hospital for oppressive chest pain radiating to the jaw lasting at least 30 minutes after an attempted strangulation by a family member. She denied any conventional cardiovascular risk factor; she was taking beta–blockers (BB) to reduce symptomatic and idiopathic premature ventricular complexes (PVCs) burden. On arrival, the patient was hemodynamically stable, reporting only swallowing difficulties. Physical examination revealed neck bruising and irregular pulse. The initial ECG showed sinus rhythm with a heart rate of 62 bpm, PVCs and a biphasic T wave in lead aVL. Hs–cTnI first dosage was 145 pg/mL. Transthoracic echocardiography (TTE) found moderate left ventricular (LV) dysfunction and severe hypokinesis of mid septal and mid inferior segments. Coronary angiography revealed normal coronary arteries. Left ventriculogram showed hypokinesis of the midventricular section with a hyperdynamic base and apex suggestive of mid–ventricular variant of TTS. After a few hours, she experienced a lipothymic episode and telemetry showed marked sinus bradycardia followed by multiple sinus pauses. A TTE was immediately performed, demonstrating a worsening LV ejection fraction with new development of severe symmetrical akinesia of the LV apex. Successively, psychotherapy was started. Wall motion abnormalities and LV systolic function completely recovered over a few days. At present the patient is in good health status. Discussion domestic violence against women is prevalent, but it is often omitted as a potential stress trigger that affects their hearts. In Italy, it’s reported that 32% of women had experienced physical violence. Strangulation is very uncommon as cause of TTS and psychotherapy may prevent recurrences and recover in a shorter time. Bradycardia due to atrioventricular block and asystole has been described in the acute phase of TTS and it is often attributed to BB therapy. Although BB have been proposed to add further benefit of blunting the effect of catecholamine excess, their use should be used cautiously in the acute phase of TTS. Moreover, beta–adrenoceptor hypersensitivity may generate a parasympathetic drive when on BB infusion, provoking a worsening LV dysfunction and a transient sick sinus syndrome as we described.

ELECTROCARDIOGRAPHIC DIAGNOSIS OF LEFT VENTRICULAR MYOCARDIAL HYPERTROPHY (LITERATURE REVIEW)

Left ventricular hypertrophy (LVH) is one of the most important predictors of cardiovascular events in patients with arterial hypertension (AH). Literature data on the role of electrocardiography (ECG) in diagnosing left ventricular (LV) myocardial hypertrophy are presented. Recommendations of the European Society of Cardiology and the European Society of Hypertension from 2018 and International Clinical Protocols "Duodecim" state the following LVH criteria: Sokolov-Lyon criteria: SV1 + RV5 > 35 mm; wave R in lead aVL > 11 mm; SV1 ≥ 25 mm, RV5–V6 > 25 mm; Cornell voltage index: SV3 + RaVL >20 mm in women and >28 mm in men; Cornell product: the product of the Cornell voltage index and the duration of the QRS complex (RaVL + SV3) × QRS – for men and (RaVL + SV3 + 8) × QRS – for women. The criteria of LVH is the value of the Cornell product > 2440 mm×ms. However, ECG criteria for detecting LVH are not sensitive enough. Peguero JG, Lo Presti S, et al. (2017) developed a more accurate method of diagnosing LVH by measuring the amplitude of the deepest S wave (SD) in any individual lead and adding it to the amplitude of the S wave in lead V4 (SV4) [SD+ SV4]. When the sum of [SD+ SV4] exceeds 28 mm in men or 23 mm in women (Peguero-Lo Presti criteria), LVH can be diagnosed.Objective: to systematize modern literary data on electrocardiographic diagnosis of left ventricular myocardial hypertrophy. Conclusion. Due to its low cost, easy availability, reproducibility and high specificity, electrocardiography remains the simplest and most common method of diagnosing myocardial hypertrophy. The Peguero-Lo Presti criteria for diagnosing left ventricular hypertrophy are more sensitive and specific than the voltage criteria of Sokolov-Lyon and Cornell.

Diagnostic performance of machine learning on 12-lead electrocardiogram for predicting multi-vessel coronary vasospastic angina

Abstract Background Multi-vessel coronary vasospastic angina (multi-VSA) is life-threatening disease. However, 12-leads electrocardiogram (ECG) in no chest symptom period was considered to have no predictive value for the multi-VSA. We tried to predict multi-VSA by machine learning (ML) on parameters of the 12-lead electrocardiogram. Purpose To predict multi-VSA by machine learning on ECG parameters in no chest pain period. Methods We recruited 227 consecutive sinus-rhythm patients (63.6±12.9years, 136men) who underwent acetylcholine-provocation test in coronary angiography (CAG). Multi-VSA was defined as spasm in at least 2 major branches which was provoked by ACh. ECG was recorded before CAG in no chest pain period. ML was performed on table data of ECG parameters (ex. ST level ant J point, R wave amplitude, and/or J wave in each lead) using several ensemble learning methods. Results 79 patients (35%) showed multi-VSA, and the breakdown of the multi-VSA was as follows: double vessel 44, triple vessel 35, including LAD 73, LCx 47, RCA73. Univariate logistic regression analysis extracted 23 significant but weak predictors, the highest area under receiver operating characteristics curve (AUROC) was 0.673 of Q wave amplitude in lead aVL. Conversely, ML demonstrated high diagnostic performance (AUROC of extra trees classifier: 0.817). Shapley additive explanation method in the extra trees showed male, QTc, J wave in lead II, and low amplitude of Q wave in lead I/aVL played essential roles to build the ML model. Conclusion Several parameters of 12-lead ECG in multi-VSA patients contains potential features of VSA, and their aggregation and ensemble learning can predict VSA with high diagnostic performance.

Detection and classification of atrial and ventricular cardiovascular diseases to improve the cardiac health literacy for resource constrained regions.

ECG is a non-invasive way of determining cardiac health by measuring the electrical activity of the heart. A novel detection technique for feature points P, QRS and T is investigated to diagnose various atrial and ventricular cardiovascular anomalies with ECG signals for ambulatory monitoring. Before the system is worthy of field trials, it is validated with several databases and recorded their response. The QRS complex detection is based on the Pan Tompkins algorithm and difference operation method that provides positive predictivity, sensitivity and false detection rate of 99.29%, 99.49% and 1.29%, respectively. Proposed novel T wave detection provides sensitivity of 97.78%. Also, proposed P wave detection provides positive predictivity, sensitivity and false detection rate of 99.43%, 99.4% and 1.15% for the control study (normal subjects) and 82.68%, 94.3% and 25.4% for the case (patients with cardiac anomalies) study, respectively. Disease detection such as arrhythmia is based on standard R-R intervals while myocardial infarction is based on the ST-T deviations where the positive predictivity, sensitivity and accuracy are observed to be 94.6%, 84.2% and 85%, respectively. It should be noted that, since the frontal leads are only used, the anterior myocardial infarction cases are detected with the injury pattern in lead avl and ST depression in reciprocal leads. Detection of atrial fibrillation is done for both short and long duration signals using statistical methods using interquartile range and standard deviations, giving very high accuracy, 100% in most cases. The system hardware for obtaining the 2 lead ECG signal is designed using commercially available off the shelf components. Small field validation of the designed system is performed at a Public Health Centre in Gujarat, India with 42 patients (both cases and controls). 78.5% accuracy was achieved during the field validation. It is thus concluded that the proposed method is ideal for improvisation in cardiac health monitoring outreach in resource constrainedregions.

Isolated T wave Inversion in Lead aVL as an early sign of Inferior Wall Myocardial Infarction

Electrocardiogram (ECG) is instrumental in identifying acute myocardial infarction (AMI). ST-segment elevation in a region of specific coronary vessels in an acute coronary syndrome (ACS) setting is the hallmark of AMI. Reciprocal ST depression and T wave inversion (TWI) are well-recognized changes that could accompany ST segment elevations. Reciprocal changes may represent the only early manifestation of AMI and may be present in specific leads such as lead aVL as early and sensitive markers of AMI. Abnormalities in the ST segment and T wave can result from non-ACS causes, but early recognition and appropriate intervention are paramount for patients with ACS. We report a case of a 55-year-old male with acute IWMI with early reciprocal and dynamic ECG changes with a literature review.

Combination of current and new electrocardiographic-based criteria: a novel score for the discrimination of left bundle branch capture.

Most of the criteria used to diagnose direct capture of the left bundle branch (LBB) have never been validated in an external sample. We hypothesized that lead aVL might add relevant information, and the combination of several electrocardiograph (ECG)-based criteria might discriminate better LBB capture from left ventricular septal (LVS) capture, than each criterion separately. Single-centre study involving all consecutive patients who received LBB area pacing. LBB capture was defined according to QRS morphology transition criteria during decremental pacing. Multivariate logistic regression analysis was performed to develop a predictive score for LBB capture. A total of 71 patients with confirmed LBB capture were analysed. The optimal cut-off values of R wave peak time (RWPT) in lead V6 (V6-RWPT) and V6-V1 interpeak interval for the discrimination of LBB capture were <83 ms and ≥33 ms, respectively. The RWPT in lead aVL (aVL-RWPT) showed a good discrimination power for the differential diagnosis of LBB capture and LVS capture. The optimal value for aVL-RWPT was 79 ms [sensitivity (SN) and specificity (SP) of 71.2% and 88.4%, respectively]. A new score, with a good diagnostic performance (area under the curve of 0.976), was constructed gathering the information from V6-RWPT, aVL-RWPT, and V6-V1 interpeak interval. The optimal score of 3 points showed a SN and SP of 89.2% and 100%, respectively for the differentiation of LBB capture. ECG-based criteria are useful to confirm the capture of the LBB. The combination of V6-RWPT, aVL-RWPT, and V6-V1 interpeak interval values demonstrated better diagnostic performance than isolated measurements.

Machine learning models of 6-lead ECGs for the interpretation of left ventricular hypertrophy (LVH)

BackgroundLeft Ventricular Hypertrophy (LVH) is closely linked to the cardiovascular disease prognosis, and thus, timely diagnosis improves outcomes. Diagnosis is challenging due to dependency on doctor's visits and a 12‑lead ECG. In addition, the interpretation of LVH from ECGs is challenging due to variability of ECG measurements, body habitus, electrode positioning, several LVH ECG criteria and EP mechanisms. The aims of this study are to evaluate different big data-driven machine learning models for ECG LVH interpretation based on limb leads only, and to compare the performance of an ECG parameter-based statistical model with a deep learning-based model. Methods and dataThe first two models are binary class Random Forest (RF) models, an ensemble learning method which constructs many decision trees at training time and predicts the class chosen by the greatest number of trees at inference time. One random forest is trained using the following five features: lead aVL R-wave amplitude, lead I, II, aVL ST segment amplitude, and QRS duration. The second RF model uses 54 features across all limb leads, including the five features used by the smaller model. The second type of model is a multi-class deep neural network (DNN) which takes median beats of 6 limb leads arranged in Cabrera sequence as input. The signal preprocessing included forming median beats, filtering with a 40-Hz lowpass filter, and down-sampling to 125 Hz. The DNN models consist of 1 lead-formation convolutional layer, 5 downsampling convolutional resnet blocks with skip connections, and 3 fully connected layers. The training dataset consisted of 1 million 10-s 12‑lead ECGs, and an independent test dataset consisted of 250,000 10-s ECGs from the Mayo Clinic. ResultsThe five-parameter RF model has the prediction performance of Area Under the Receiver-Operator Curve (AUC) 0.78, and the larger RF model had AUC of 0.83. The DNN model for ECG LVH detection achieves AUC 0.92 using only the limb leads, compared to an AUC of 0.98 for the full 12‑lead DNN. ConclusionThe study shows that machine learning models trained only on limb leads achieve promising results with potential to add clinical value to early detection mechanisms. We also observe that the RF model splits parameters by thresholds known to be characteristic of LVH, and that the DNN model can automatically detect morphology differences from 6 limb lead ECGs. This will be meaningful for expanding the capabilities of potential electrical LVH detection in mobile 6‑lead ECG devices.

Utility of the aVL Lead in the Electrocardiographic Diagnosis of Atrioventricular Nodal Re-Entrant Tachycardia

Background: Reciprocating atrioventricular tachycardia can be categorized into common slow–fast atrioventricular node re-entrant (AVNRT) and orthodromic atrioventricular reciprocating tachycardia (AVRT). The electrocardiogram (ECG) during tachycardia is useful in distinguishing these two mechanisms. The presence of a pseudo- R0-wave in lead V1 or pseudo-S-wave in the inferior leads has been widely used, although the value of an isolated aVL lead has not been evaluated yet. To determine whether an isolated aVL lead of the surface 12-lead ECG is useful for the differential diagnosis between AVNRT and AVRT. Methods: This cross sectional observational study was conducted at the department of Cardiology, National Institute of Cardiovascular Diseases &amp; Hospital, for 1-year period. Patient admitted in NICVD due to supraventricular tachycardia and was screened as a case of AVNRT &amp; AVRT were approached for inclusion of the study. After initial management all patients were subjected to perform electrophysiological study and radiofrequency ablation. The specific pattern of changes in aVL lead were recorded in each cases and were analyze to determine the sensitivity, specificity and positive predictive values to estimate AVRT &amp; AVNRT. Informed written consent was taken from the subject and ethical issues were ensured. Total 60 patients were included for final analysis. Data analysis was done by statistical program Statistical Package for Social Science (SPSS) version 20.0. Results: Among the 60 study population, mean age was 41.28±11.21 SD (years) [age range: 18-65 years]. Total 44 patients (73%) had AVNRT and 16 patients (27%) had found AVRT in Electrophysiological evaluation. About 61.7% patients were female and 38.3% patients were male in this study with no significant gender difference in between AVNRT and AVRT group (p&gt;0.05). Total 43.3% patients had aVL notch on ECG. Among patients who had AVNRT, 54.5% had aVL notch and among patients who had AVRT, 12.5% had aVL .........

Screening for hypertension-mediated organ damage and aetiology: still of value after 65 years of age?

Secondary forms and hypertension-mediated organ damage (HMOD) may differ between younger and older hypertensive patients. The aim of the present study was to explore the specificity of HMOD and secondary forms in patients ≥ 65 years in comparison to younger ones in a contemporary cohort. We analysed 938 patients recruited between 2004 and 2014 (Cardiology department, Croix-Rousse Hospital, Lyon) who had at baseline HMOD and secondary forms screening among them 190 were ≥ 65 years. The mean (2.1 ± 0.8 vs. 1.2 ± 0.9, P < 0.001) and frequency of HMOD (96.3% vs. 72.9%, P < 0.001) was higher in patients ≥ 65 years than younger ones. Carotid femoral pulse wave velocity > 10 m/s was the most frequent HMOD in patients ≥ 65 years (90.1%), while echocardiographic left ventricular hypertrophy was the most common in the younger patients (45.0%). Among ECG left ventricular indexes, only R wave in aVL lead was significantly more frequently observed in patients ≥ 65 years (32.6%) than in younger ones (19.0%, P < 0.001). The frequency of secondary hypertension was not significantly different between younger and older patients (respectively; 30.5% vs. 27.8%, P = 0.487). The most frequent aetiology was primary aldosteronism regardless of age, followed by renovascular hypertension (6.3% vs. 3.3%, P = 0.038). Among older patients, 3.2% were treated with adrenalectomy and 6.3% with percutaneous transluminal renal angioplasty. Extensive screening of HMOD in older patients may be questionable as nearly all patients had one; aetiology must however be explored as a third of older patients had a secondary form.

Abstract 11580: Clinical Validation of a Smartphone Compatible 6L Electrocardiogram Device in Ambulatory Patients

Introduction: Novel ECG devices seek to facilitate easier obtainment of ECG recordings, while not compromising accuracy, compared to a standard clinical 12-L ECG. We aimed to compare the accuracy of the AliveCor Kardia 6L device with simultaneously recorded 12-L ECG recording with the patient in the same position. Hypothesis: The AliveCor Kardia 6L ECG device demonstrates data highly correlated with a standard 12-L ECG. Methods: We included patients seen in an outpatient cardiology clinic. ECG data using the Kardia 6L and a standard 12-L were obtained simultaneously in the seated position. Median beats for each method were compared using Pearson’s correlation. Results: One hundred patients (mean age 57±18, 55% female) were included. Lead aVL R wave amplitude (r= 0.99), T wave amplitude (r= 0.99), T wave axis (r= 0.96) QRS axis (r= 1.00), QRS duration (r= 0.94), and QT duration (r= 0.96) demonstrated excellent correlation between the two methods (Figure). Conclusion: The 6L Kardia device allows for accurate ECG measurements in ambulatory patients. This illustrates implications for the diagnosis of cardiac diseases, including left ventricular hypertrophy, in both clinical and nonclinical settings.

Promise or peril: the ECG in HCM

Abstract Introduction Hypertrophic cardiomyopathy is a complex disease of the myocardium characterised by left ventricular hypertrophy &amp;gt;15mm in any one segment, in the absence of loading conditions. The phenotypic variability and inhomogeneous nature of the condition have resulted in difficulties with diagnosis. Despite the significant progression in cardiac imaging and genetics, the electrocardiogram (ECG) remains the cornerstone of initial evaluation of patients with HCM and in the screening of families. Moreover, the ECG is in widespread use for pre-participation sports screening. Purpose Original and contemporary studies indicate that the ECG is normal in only 6–10% of patients with echocardiographic evidence of HCM. We hypothesised that the ECG may be normal in a significant proportion of HCM patients. This study sought to reassess the ECG as a screening tool in a HCM cohort. Methods 112 patients were selected randomly from the database of a specialist cardiomyopathy clinic. Their most recent ECG, clinical and imaging data were reviewed. All patients had echocardiographic HCM and were carriers of pathogenic sarcomere gene mutations. Patients with phenocopies were excluded. ECG data for 100 age and sex-matched controls was also analysed. ECG interpretation was performed using international criteria. Results 18% of patients with a clinical diagnosis of HCM by conventional diagnostic standards (LV wall thickness &amp;gt;15mm) had a normal ECG. A further 7% had a normal ECG with a mild HCM phenotype (LV wall thickness of 13–14mm). The most common abnormality observed was T wave inversion (TWI) in 28%. An additional unexpected finding in the HCM group was isolated TWI in lead aVL. This occurred in 27% of patients in the absence of any other repolarisation abnormalities, compared with 1% of controls. The significance of this finding is unclear. 27% of HCM patients displayed voltage criteria for left ventricular hypertrophy by either Cornell or Sokolow-Lyon criteria, with just 4% meeting criteria for both. 13% of HCM patients had corrected QT prolongation, in the absence of medications responsible for this. Conclusion The ECG continues to play a pivotal role in HCM diagnosis but its sensitivity to detect disease has been over-estimated. Up to a quarter of patients with HCM have a normal ECG. This is significantly higher than previously reported. The ECG in isolation therefore is not a reliable tool for screening for HCM in the general population and especially unreliable in at-risk subjects. Funding Acknowledgement Type of funding sources: Foundation. Main funding source(s): The Mater Foundation

322-OR: ECG-Derived QRS-T Angle Is an Independent Predictor of Sudden Cardiac Death in Patients with Type 2 Diabetes: From the SURDIAGENE Prospective Study

Diabetes is associated with a high risk of sudden cardiac death (SCD) but the risk of non-SCD is even higher. We aimed to assess cardiac electrical markers for predicting SCD in patients with T2D. SURDIAGENE is a French prospective cohort of T2D patients. Baseline 12-lead ECG of 1285 (64±years; 43% female) patients were concordantly evaluated by 2 cardiologists to measure 15 ECG-derived markers. Causes of death were adjudicated by an independent committee. The primary outcome was SCD which was defined as a sudden, natural, and unexpected death, with preceding duration of symptoms &amp;lt;24 hours for witnessed cases and &amp;lt;1 hour witnessed cases. Bonferroni-adjusted cause-specific Cox proportional hazards and Fine and Gray competing-risk models were performed to identify independent predictors (adjustment for age, sex, HbA1c, NT-proBNP, eGFR, ACR, history of myocardial infarction, diuretic, and insulin) . At baseline, mean diabetes duration was 14±years and mean HbA1c 7.8±1.6%. During a median follow up of 7.4 years, 446 deaths occurred including 83 (18.6%) SCD. In univariate analysis, R wave voltage ≥mm in aVL lead, corrected QT interval and QRS-T angle ≥90° were associated with SCD risk at the Bonferroni-adjusted level of significance (P &amp;lt; 0.0033) . Using competing-risk multivariate analysis, QRS-T angle ≥90° only was significantly associated with a higher risk of SCD (sHR 1.63 [1.01-2.62]; P=0.045) but interestingly not with non-SCD (sHR 1.02 [0.78-1.33], P=0.87) . Discrimination of SCD prediction model was improved by QRS-T angle beyond multivariate Cox model parameters (C-statistic improved from 0.798 to 0.805, P&amp;lt;0.0001) . ECG-derived QRS-T angle is an independent predictor of SCD in patients with T2D and improves SCD-risk model prediction accuracy. Disclosure R.Garcia: Other Relationship; Abbott, Boston Scientific Corporation, Medtronic, Microport. The surdiagene study group: n/a. M.Tavernier: None. E.Gand: None. J.De keizer: None. B.Alos: None. C.Bouleti: Consultant; AstraZeneca, Novartis Pharmaceuticals Corporation, Research Support; Pfizer Inc. B.Degand: None. S.Hadjadj: Consultant; Abbott Diabetes, AstraZeneca, Boehringer Ingelheim International GmbH, Eli Lilly and Company, Novartis AG, Novo Nordisk, Sanofi, Servier Laboratories, Valbiotis, Other Relationship; Janssen Pharmaceuticals, Inc. P.Saulnier: Consultant; Grünenthal Group, Research Support; AstraZeneca, Novo Nordisk, Sanofi.

Can peak left ventricular activation time measured in aVL identify left bundle capture during left bundle branch area pacing?

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Two main types of capture are observed during left bundle branch area pacing (LBBAP): LBB pacing (selective-LBBP or non-selective LBBP) and LV septal (LVS) capture. Several criteria are used to distinguish between both types. Methods Prospective study of patients who received LBBAP device for bradycardia or heart failure indications (bailed-out strategy). LBBP was defined if monopolar paced QRS had a right bundle branch conduction delay pattern, at least one of the following criteria: (a) Demonstration of LB potential with LB-local ventricular electrogram interval of 10–35 ms. (b) Demonstration of transition in QRS morphology from non-selective to selective LB capture or non-selective to LVS capture (sudden decrease in LVAT of 10 ms) with decrementing output. (c) Peak LV activation time time as measured in leads V5–V6 &amp;lt;80 ms. Patients not fulfilling criteria for LBBP were catalogued as LVS pacing. We analyzed the role that peak LVAT in the lead aVL (measured from the onset of the pacing spike to the peak of the R wave) had to discriminate between LBBP and LVS pacing and its correlation with LVAT measured in V5-V6. Results 154 consecutive LBBAP procedures were included. Success was achieved in 150 patients (97,4%). Mean age at implant was 79.4±9.3 years, native QRS duration was 118.7±29.4 ms, and LVEF was ≤ 40% in 16 (10,5%). A narrow (&amp;lt; 120 ms) QRS complex was present in 82 patients (53,2%) and LBBB was present in 21 patients. Indications for pacing were second- or third-degree AV block (n=57), slow AF (n=22), bifascicular or trifascicular block (n=12), sinus node disease (n=56) and need for resynchronization therapy (n=6). A Medtronic 3830-69 lead was implanted using a C-315-His sheath in all procedures. We did not perform His mapping to select the target delivery zone. LBBP was achieved in 117 patients (NSLBBP in 67 and SLBBP in 50) while LVS was achieved in the remaining 30 patients. Paced QRS duration after LBBAP was 115.3±14.7 ms, with a mean LVAT (measured at V5/V6) of 79.8±11.3 ms and mean LVAT in aVL of 83.6±14.6 ms. Left bundle potential was seen in 64 patients (44.4% of total population. LVAT in both V5/V6 and aVL was longer in LBBP patients compared to LVS patients (table 1). Accuracy of LVAT measured in aVL for the differential diagnosis of LBBP and LVS capture was good (AUC 84,6%). The diagnostically optimal value for discrimination among the two types of capture was 84 ms (sensitivity and specificity of 65.5% and 93.3%, respectively) (Panel A, figure 1). Moreover, ROC curve for discrimination between patients with LVAT in V5/V6&amp;lt;80 ms and &amp;gt;80 ms was also good (AUC 87.8%). A cut-off point for LVAT in aVL &amp;lt; 84 ms was also the diagnostically optimal value with a sensitivity and specificity of 80.2% and 80%, respectively). (Panel B, figure 1) Conclusions Peak LVAT measured in aVL lead might be a useful tool during LBBAP for differentiation between LBB capture and LVS capture.

Is It ST-Segment-Elevation Myocardial Infarction?

A 76-year-old man presented with acute-onset chest pain and dyspnea. He had a history of coronary artery disease, ischemic cardiomyopathy (left ventricular ejection fraction, 25%), recent non-ST-segment-elevation myocardial infarction (NSTEMI), and stenting of the left anterior descending coronary artery (LAD) one month before the current presentation. Soon thereafter, he underwent stenting of the left main coronary artery (LMCA), obtuse marginal branch (OMB), and left circumflex coronary artery. His chest pain subsided soon after arrival at the emergency department. His cardiac troponin I level was 22 ng/mL (normal level, &lt;0.03 ng/mL), and his brain natriuretic peptide level was 841 pg/mL (normal level, &lt;100 pg/mL). Figure 1 shows his electrocardiogram (ECG).What is the diagnosis?C) STEMI due to first OMB or ramus intermedius occlusionThe ECG shows sinus rhythm, mild ST-segment elevation (STE) with T-wave inversion in lead aVL, ST-segment depression with positive T waves in leads II, III, aVF, and V3 through V6, and an isoelectric ST segment in leads I and V1 through V2. The Fourth Universal Definition of Myocardial Infarction1 says, “More profound ST-segment shifts or T-wave inversions involving multiple leads/territories are associated with a greater degree of myocardial ischaemia, and a worse prognosis. For example, ST-segment depression ≥1 mm in 6 leads, which may be associated with STE in lead aVR or lead V1 and hemodynamic compromise, is suggestive evidence of multivessel disease or left main disease” (eliminating answer A). This is considered a high-risk ECG pattern for which invasive intervention within 2 hours is recommended, in accordance with the 2020 European Society of Cardiology guidelines for managing acute coronary syndromes without persistent STE.2 Our patient's ECG shows ST-segment depression in 7 leads but no significant STE in lead aVR or V1. In contrast, STE with negative T waves is seen in lead aVL.Patients with a nonischemic early repolarization pattern can have STE in lead aVL. However, the T waves are usually positive, and there is often a J-point notch. The pattern here suggests a reperfused or more advanced stage of STEMI,3 and the patient's clinical presentation (symptom resolution after hospital arrival) supports this diagnosis.New STE in 2 contiguous leads is necessary for the diagnosis of STEMI.1 However, this is an epidemiologic (not pathophysiologic) criterion, to minimize false-positive diagnosis. Acutely occluded arterial branches may cause STE in only one lead with diffuse ST-segment depression.4 The STE in leads aVL and V2 through V5 is caused by LAD occlusion proximal to the first diagonal branch (eliminating answer B),4 and STE in leads aVL and V2 without STE in leads V3 through V5 suggests an occluded first diagonal branch. The ST-segment depression in the anterolateral and inferior leads is incompatible with the typical presentation of takotsubo cardiomyopathy (answer D). The STE in lead aVL, incompatible with ischemic cardiomyopathy (answer E), is accompanied by ST-segment depression in lead V2, suggesting obstruction of the first OMB. Our patient had an isoelectric ST segment in lead V2, so the differential diagnosis is an occluded OMB or ramus intermedius.4 A coronary angiogram on the second day of admission showed subacute thrombotic occlusion of the first OMB (Fig. 2, arrow), and stenting restored patent flow.Disclosures: NoneFunding/support: None

Screening for hypertension-mediated organ damage and aetiology: Still of value after 65 years of age?

Pathophysiological aspects and the consequences of hypertension may differ between younger and older patients. The aim of the present study was to explore the specificity of hypertension-mediated organ damage (HMOD) and secondary forms in patients ≥ 65 years in comparison to younger ones in a contemporary cohort. A total of 938 hypertensive patients who had at baseline HMOD and secondary forms screening were included among them 190 were ≥ 65 years. The mean ± SD number (2.1 ± 0.8 vs. 1.2 ± 0.9, P < 0.001) and frequency of HMOD (96.3% vs. 72.9%, P < 0.001) was higher in patients ≥ 65 years than younger ones. Carotid femoral pulse wave velocity > 10 m/s was the most frequent HMOD in patients ≥ 65 years (90.1%), while echocardiographic left ventricular hypertrophy was the most common in the younger patients (45.0%). Among ECG left ventricular ECG indexes, only R wave in aVL lead was significantly more frequently observed in patients ≥ 65 years (32.6%) than in younger ones (19.0%, P < 0.001). The frequency of secondary hypertension was not significantly different between younger and older patients (respectively; 30.5% vs. 27.8%, P = 0.487). The most frequent aetiology was primary aldosteronism regardless of age. The frequency of renovascular hypertension was higher in patients ≥ 65 years (6.3% vs. 3.3%, P = 0.038). Among older patients, 3.2% were treated with adrenalectomy (primary aldosteronism or Cushing syndrome) and 6.3% with percutaneous transluminal renal angioplasty. In a tertiary centre, secondary forms of hypertension have a similar frequency in both subgroups. Extensive screening of HMOD in patients aged ≥ 65 years may be questionable because of its very high frequency.

Inter-relationships of different electrocardiographic indicators of left ventricular hypertrophy in 25,000 Chinese adults

Abstract Background Several electrocardiographic (ECG) indices have previously been proposed to diagnose left ventricular hypertrophy (LVH). Such indices utilize different criteria, including increased QRS voltage, prolonged QRS duration, left axis deviation, and LAFB and LBBB-like patterns in varying combinations. However, the inter-relationships of these different electrocardiographic indices of LVH with each otherare not fully understood. The purpose of this study is to estimate the relationships between the different LVH indices. Methods Electronic tracings of 12-lead ECGs recorded in 24,786 adult participants in the China Kadoorie Biobank recorded in 2014 were accessed to detect presence of LVH. ECG parameters of LVH, including individual and combinations of such parameters (voltage-only criteria such as Sokolov-Lyon, Cornell, Gubner as well as scores such as Romhilt-Estes point score) were estimated using customized computer software (Cardiolyse Oy, Finland) and compared proprietary LVH point score algorithms (Mortara, USA). Relationships between the different indices were assessed using a correlation matrix to explore associations between individual parameters and combined indices of such parameters. The matrices were used to construct heat maps and identify clustering of individual parameters. Results Overall, approximately 10% of the population had LVH assessed by Mortara algorithms. This graph shows that along with the free standing peaks, the rest are divided into two clusters of interconnected individual parameters. In the center of the largest cluster is the parameter, reflecting R-peak magnitude in aVL lead. In the center of another cluster was the left ventricular strain pattern, as described in Romhilt-Estes point score system. Overall, the Sokolov-Lyon index and LVH point score in Veritas algorithm had the strongest relationships with each other, but the Gubner and Cornell indices had relatively weak correlations with the other indices (Table 1). The mean correlation coefficient between five combined LVH indices was as follows: Veritas (Mortara) – 0.58, Sokolov-Lyon – 0.56, Romhilt-Estes – 0.45, Gubner – 0,32, Cornell – 0,3. Conclusions Parameters such as R-peak magnitude in aVL and left ventricular strain pattern were the most strongly related with each other. Aggregate indices, such as the Sokolov-Lyon index and LVH point score in Veritas algorithm were the most strongly related with all other indices, but the Gubner and Cornell indices were only weakly correlated. The results reinforce the utility of Sokolov-Lyon index and Mortara algorithms as the optimum measures of LVH. Funding Acknowledgement Type of funding sources: None.

A Two Channels Wireless Electrocardiograph System Using Bluetooth Communication

Health problems with cardiovascular system disorders are still ranked high, according to data from the WHO reported that there are about 31% of causes of death globally are cardiovascular diseases. The purpose of this study was to develop a 12 lead electrocardiograph with 2 displays and the HC-05 as a real-time transmitter of heart signal data. The electrocardiogram signal is obtained from the wiretapping by attaching the electrode cable to the Lead I, Lead II, Lead III, aVR, aVL, and aVF leads, then processed on IC AD620, HPF and LPF filters and non-inverting amplifiers and then processed using Arduino UNO for further display. in the form of a signal on the Delphi 7 application. The research method is to measure the heart signal on the ECG Simulator, by testing several BPMs, namely 30, 60, 120 and 240 on each lead. After testing the signal equation at the 0.5mV setting by calculating the error rate, the highest error value is obtained in lead I, lead aVL and aVF of 7.14% and the smallest error is 3.57% error in lead III. Then at the 1mV setting by calculating the error rate, the highest error value in lead aVL is 7.14% and the smallest error is 2.36%. at the 2mV setting by calculating the error rate, the highest error value is obtained in leads aVL and aVF of 5.71% and the smallest error is obtained by an error of 2.1% in lead II. the results of this study are implemented so that in the future an ECG examination can be carried out and then monitored remotely like a doctor's room because the data communication uses bluetooth.

А new electrocardiographic criterion in diagnosis right ventricular myocardial infarction

The aim of this study is to identify the features of ST-changes in 12-leads surface ECG, which help to diagnose the right ventricular involvement in inferior myocardial infarction. The study included 145 patients with inferior myocardial infarction, the right ventricular infarction (RVI) was detected by echocardiography in 62 (42.8%) patients. ST segment depression in lead aVL was deeper than in lead V3 in 93.5% of patients with RVI. This feature is revealed in 4.9% patients with inferior myocardial infarction without RVI only. The sensitivity of this criterion for diagnosis RVI is 93.5%, the specificity is 95.2%, the predictive value of positive and negative results make up 93.5 and 95.2%.

Performance of a novel ECG criterion for improving detection of left ventricular hypertrophy: a cross-sectional study in a general Chinese population

ObjectivesThe sensitivity of ECG for detecting left ventricular hypertrophy (LVH) is low. The aim of this study was to explore a better ECG criterion for screening LVH in a large...

The Changes of T-Wave Amplitude and QT Interval Between the Supine and Orthostatic Electrocardiogram in Children With Dilated Cardiomyopathy.

Objectives: Electrocardiogram (ECG) can be affected by autonomic nerves with body position changes. The study aims to explore the ECG changes of children with dilated cardiomyopathy (DCM) when their posture changes.Materials and methods: Sixty-four children diagnosed with DCM were recruited as research group and 55 healthy children as control group. T-wave amplitude and QT interval in ECG were recorded, and their differences between supine and orthostatic ECG were compared in both groups. Subsequently, the children with DCM were followed up and the differences before and after treatment compared.Results: ① Comparisons in differences: Differences of T-wave amplitude in lead II and III, aVF, and V5 and differences of QT interval in lead II, aVL, aVF, and V5 were lower in the research group than in the control group. ② Logistic regression analysis and diagnostic test evaluation: The differences of T-wave amplitude in lead III and QT interval in lead aVL may have predictive value for DCM diagnosis. When their values were 0.00 mV and 30 ms, respectively, the sensitivity and specificity of the combined index were 37.5 and 83.6%. ③ Follow-up: In the response group, the T-wave amplitude difference in lead aVR increased and the difference of QT interval in lead V6 decreased after treatment. In the non-response group, there was no difference before and after treatment. When the combined index of the differences of T-wave amplitude difference in lead aVR and QT interval difference in lead V6, respectively, were −0.05 mV and 5 ms, the sensitivity and specificity of estimating the prognosis of DCM were 44.4 and 83.3%.Conclusions: The differences of T-wave amplitude and QT interval may have a certain value to estimate DCM diagnosis and prognosis.