ASSOCIATION OF ST ELEVATION IN LEAD AVR WITH LEFT MAIN STEM AND TRIPLE VESSEL DISEASES IN PATIENTS WITH NON-ST ELEVATION MYOCARDIAL INFARCTION

Objectives: To determine frequency of left main stem (LMS) and triple vessel coronary artery disease (3VCAD) in patients of Non-ST-elevation myocardial infarction (NSTEMI) and to compare the frequency of LMS and 3VCAD in patients with NSTEMI with or without ST elevation in lead aVR. Methodology: Total 346 patients with NSTEMI having age 30-70 years were included in this descriptive cross-sectional study. The data on demographic details was collected. All patients underwent electrocardiography (ECG) and cardiac specific troponin-I assessment. Patients were categorized as NSTEMI with or without ST-elevation in lead aVR. Coronary angiography was performed in all patients and angiographic findings were noted. Results: Mean age of patients was 51.87±10.03 years. There were 218 (63.01%) males and 128 (36.99%) female patients. 182 (52.60%) patients of NSTEMI had ST elevation in aVR. LMS disease was found in 53 (29.10%) patients with ST elevation in aVR. Sensitivity, specificity, positive predive value and negative predictive value of ST elevation in aVR for LMS disease was 62.35%, 50.57%, 29.12% and 80.49% respectively. 3 VCAD was found in 54 (29.70%) with ST elevation in aVR. Sensitivity, specificity, positive predive value and negative predictive value of ST elevation in aVR for 3VCAD was 77.14%, 53.52%, 29.67% and 90.24% respectively. Conclusion: NSTEMI patients with ST elevation in aVR may have higher chances of having LMS disease or 3VCAD. There is high negative predictive value for ST elevation in aVR to predict LMS disease or 3VCAD.

A Study of the ST Changes in the aVR Lead on 12-Lead ECG to Identify Infarct - Related Artery (IRA) in Patients With Acute Inferior Wall Myocardial Infarction

BACKGROUND: Lead avR is a valuable but mostly ignored lead in clinical electrocardiography. Recently, ST-segment depression in lead aVR during an inferior wall myocardial infarction has been suggested as a predictor of LCX artery involvement. METHODS: This study was a single centre cross sectional observational study done in BPKIHS, Dharan from February 2018 to January 2020. Patients presenting to the OPD or emergency room of BPKIHS diagnosed as acute inferior wall myocardial infarction based on clinical symptoms, ECG and/or Cardiac tropinin I levels, and planned for coronary angiography, meeting the inclusion and exclusion criterias were included. RESULTS: Among 134 cases, male:female ratio was 1.3:1. Overall, 38 patients (28.4%) were found to have aVR depression and 96 patients (71.6%) were without aVR depression. The culprit artery was found to be the right coronary artery in 95 patients (70.9%), the LCx in 39 patients (29.1%). The sensitivity and specificity of ST-segment depression in lead aVR for LCx as the culprit artery were 92.3% and 97.9% respectively. Positive predictive and Negative predictive value for LCx as the culprit arteries were 94.74% and 96.87%. The sensitivity, specificity, positive predictive value and negative predictive value for RCA as the culprit artery were 97.89%, 92.3%, 96.89% and 94.73% respectively. CONCLUSION: Significant ST depression in aVR is associated with a higher specificity and good sensitivity for LCX lesions, the ST changes in this lead should be carefully examined in all patients who are suspected of having inferior wall myocardial infarction.

The Added Value of ST-Elevation in Lead aVR to Clinical TIMI Score in Predicting the Angiographic Severity of Coronary Artery Disease in Patients with Non ST-Elevation Myocardial Infarction

Background Atherosclerosis is the ongoing process of plaque formation involving primarily the intima of large and medium-sized arteries. The condition progresses relentlessly throughout a person’s lifetime, before finally manifesting itself as an acute ischemic event. TIMI score is a tool of 7 points for patients with NSTE-ACS to detect the risk according to the score. The term acute coronary syndrome (ACS) includes unstable angina (UA), non STsegment elevation myocardial infarction (NSTEMI), and ST-segment elevation myocardial infarction (STEMI). Aim To investigate the added value of the presence of ST-segment elevation in lead avR on admission electrocardiogram to the (TIMI) clinical scoring system in predicting the angiographic severity of coronary artery disease in patients admitted with NSTE-ACS. Patients and Methods 150 patients with Non ST-segment elevation acute coronary syndrome was included from Cardiology Department, Ain Shams University Hospital, Cairo, Egypt. Results From those patients, 137 patients (91.3%) diagnosed by coronary angiography to have significant CAD and 93 patients (62%) had ST-Elevation in lead aVR . These 137 patients were divided into 3 groups according to TIMI risk score to 16 patients (10.6%) had low risk score, 63 patients (42.0%) had intermediate risk & lastly 58 patients (38.7%) had high risk score. . Although being useful in prediction of multi-vessel & LM involvement among high risk group, TIMI score failed to predict the same in intermediate & low risk groups where multi-vessel involvement was found in 46 patients (30.6%) & 7 patients (4.6%) of intermediate & low risk groups respectively. Also LM involvement was found in 15 patients (10%) & 2 patients (1.3%) of intermediate & low risk groups respectively. Conclusion ST-segment elevation (STE) in lead avR had an adding predicting value in NSTEACS patients especially those with low to intermediate TIMI score. Adding the value of STE in lead aVR to TIMI risk score may improve the early stratification & management of those patients at high risk coronary artery disease, with subsequent impact on morbidity & mortality.

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.

Standard ECG in Brugada Syndrome as a Marker of Prognosis: From Risk Stratification to Pathophysiological Insights

Background The 12‐lead ECG plays a key role in the diagnosis of Brugada syndrome (BrS). Since the spontaneous type 1 ECG pattern was first described, several other ECG signs have been linked to arrhythmic risk, but results are conflicting. Methods and Results We performed a systematic review to clarify the associations of these specific ECG signs with the risk of syncope, sudden death, or equivalents in patients with BrS. The literature search identified 29 eligible articles comprising overall 5731 patients. The ECG findings associated with an incremental risk of syncope, sudden death, or equivalents (hazard ratio ranging from 1.1–39) were the following: localization of type 1 Brugada pattern (in V2 and peripheral leads), first‐degree atrioventricular block, atrial fibrillation, fragmented QRS, QRS duration >120 ms, R wave in lead aVR, S wave in L1 (≥40 ms, amplitude ≥0.1 mV, area ≥1 mm 2 ), early repolarization pattern in inferolateral leads, ST‐segment depression, T‐wave alternans, dispersion of repolarization, and Tzou criteria. Conclusions At least 12 features of standard ECG are associated with a higher risk of sudden death in BrS. A multiparametric risk assessment approach based on ECG parameters associated with clinical and genetic findings could help improve current risk stratification scores of patients with BrS and warrants further investigation. Registration URL: https://www.crd.york.ac.uk/prospero/ . Unique identifier: CRD42019123794.

Lead aVR predicts early revascularization but not long-term events in patients referred for stress electrocardiography

Background Exercise stress electrocardiography (ExECG) is recommended as a first-line tool to assess ischemia, but standard ST-analysis has limited diagnostic accuracy. ST elevation in lead aVR has been associated with left main and LAD disease in the population undergoing coronary angiography but has not been studied in the general population undergoing stress testing for the initial evaluation of CAD without coronary angiography. We sought to determine the predictive value of lead aVR elevation for ischemia, early revascularization, and subsequent cardiac events in consecutive patients undergoing ExECG. Methods and results The study cohort included 641 subjects referred for ExECG who were dichotomized by presence or absence of aVR elevation ≥1mm and compared for prevalence and predictors of ischemia and a composite of cardiac death, nonfatal myocardial infarction, and late revascularization. The cohort had a median age of 57 and 57% were male. The prevalence of aVR elevation was 11.5%. The prevalence of significant ischemia on patients who received imaging was significantly higher with aVR elevation (14.3% vs 2.3%, p<0.001). Early revascularization occurred in 10.9% with vs 0.2% without aVR elevation, p<0.001. No subjects without aVR elevation or ST-depression underwent early revascularization. However, cardiac event rates were similar over a median 4.0 years of follow-up with and without aVR elevation (2.8% vs. 2.6%, p = 0.80). aVR elevation did not predict long-term cardiac events by Kaplan-Meier survival analysis (p = 0.94) or Cox proportional hazards modeling (p = 0.35). Conclusions aVR elevation during ExECG predicts ischemia on imaging and early revascularization but not long-term outcomes and could serve as a useful adjunct to standard ST-analysis and potentially reduce the need for concurrent imaging.

ST Elevation in Lead aVR with Malperfusion Syndrome: Sign of Severe Aortic Dissection

Aortic dissection presenting with ST elevation in lead aVR of electrocardiogram is strongly associated with mortality. It is also associated with dissection involving the root of aorta and coronary vessels. We report a case of young male with hypertension, who presented with severe chest pain and unilateral lower limb pain. Physical examination of the left lower limb was consistent with acute limb ischemia. Electrocardiogram revealed acute anterolateral myocardial infarction together with ST elevation in aVR. Bedside transthoracic echocardiography showed a dilated aortic root measuring 4.51 cm with presence of intimal flap which raised the suspicion of dissection of root of aorta and left coronary artery. Computed tomography angiogram revealed aortic dissection from the root of aorta including the intimal flap near the origin of the left coronary artery, down to common iliac extending to the left iliac artery. Unfortunately, the patient opted for non-surgical intervention and succumbed 48 hours later. This case highlights that in case of aortic dissection, which presents with malperfusion syndrome, the presence of ST segment elevation at lead aVR should raise the suspicion for extensive aortic dissection involving the aortic root and left coronary artery which signifies unfavourable outcome