Segment Elevation In Lead aVR Research Articles

P-310 Clinical Significance of ST Segment Elevation in Lead aVR as Predictor of Left Main Coronary Artery Occlusion in Acute Coronary Syndrome

P-310 Clinical Significance of ST Segment Elevation in Lead aVR as Predictor of Left Main Coronary Artery Occlusion in Acute Coronary Syndrome

ST segment elevation in lead aVr and left main coronary infarction in the post-resuscitated patient

Lead aVR is an electrocardiographic lead that is frequently ignored [1,2]. Many clinicians consider lead aVR as a not useful electrocardiogram one. Instead of this, we report a patient that was resuscitated from a ventricular fibrillation and presented with ST-elevation in lead aVr (Figures ​(Figures11 and ​and2)2) and right bundle brunch block. The patient was immediately transferred to the cath lab and a left main coronary artery occlusion (LMCA) was visualized [3]. In this emergency scenario the patient had another cardiac arrest in pulseless electric activity and we proceeded with percutaneous revascularization of the LMCA (Figure ​(Figure3).3). The patient returned to spontaneous circulation and after 14 days was dispatched from hospital without neurologic sequelae. The rapid diagnosis of such events is critical to guiding early intervention and appropriate disposition in many patients with ACS. Electrocardiography is an appropriate bedside tool used in the ED to make a rapid diagnosis of ACS especially using the aVr lead, allowing physicians to select appropriate therapy and to predict potential cardiovascular complications. Figure 1 Figure 2 Figure 3

ST segment elevation in lead aVR during exercise testing is associated with LAD stenosis

To evaluate, in patients with chest pain, the diagnostic value of ST elevation (STE) in lead aVR during stress testing prior to (99m) Tc-sestamibi scanning correlating ischaemic territory with angiographic findings. Consecutive patients attending for (99m) Tc-sestamibi myocardial perfusion imaging (MPI) completed a treadmill protocol. Peak exercise ECGs were coded. STE >or=0.05 mV in lead aVR was considered significant. Gated perfusion images and findings at angiography were assessed. STE in lead aVR occurred in 25% (138/557) of the patients. More patients with STE in aVR had a reversible defect on imaging compared with those who had no STE in aVR (41%, 56/138 vs 27%, 114/419, p=0.003). Defects indicating a left anterior descending artery (LAD) culprit lesion were more common in the STE in aVR group (20%, 27/138 vs 9%, 39/419, p=0.001). There was a trend towards coronary artery stenosis (>70%) in a double vessel distribution involving the LAD in those patients who had STE in aVR compared with those who did not (22%, 8/37 vs 5%, 4/77, p=0.06). Logistic regression analysis demonstrated that STE in aVR (OR 1.36, p=0.233) is not an independent predictor of inducible abnormality when adjusted for STD >0.1 mV (OR 1.69, p=0.026). However, using anterior wall defect as an end-point, STE in aVR (OR 2.77, p=0.008) was a predictor even after adjustment for STD (OR 1.43, p=0.281). STE in lead aVR during exercise does not diagnose more inducible abnormalities than STD alone. However, unlike STD, which is not predictive of a territory of ischaemia, STE in aVR may indicate an anterior wall defect.

Prediction of acute left main coronary artery obstruction by 12-lead electrocardiography. ST segment elevation in lead aVR with less ST segment elevation in lead V 1

Prediction of acute left main coronary artery obstruction by 12-lead electrocardiography. ST segment elevation in lead aVR with less ST segment elevation in lead V 1

Prediction of acute left main coronary artery obstruction by 12-lead electrocardiography: ST segment elevation in lead aVR with less ST segment elevation in lead V1

OBJECTIVESWe sought to determine the electrocardiographic (ECG) features associated with acute left main coronary artery (LMCA) obstruction.BACKGROUNDPrediction of LMCA obstruction is important with regard to selecting the appropriate treatment strategy, because acute LMCA obstruction usually causes severe hemodynamic deterioration, resulting in a less favorable prognosis.METHODSWe studied the admission 12-lead ECGs in 16 consecutive patients with acute LMCA obstruction (LMCA group), 46 patients with acute left anterior descending coronary artery (LAD) obstruction (LAD group) and 24 patients with acute right coronary artery (RCA) obstruction (RCA group).RESULTSLead aVR ST segment elevation (>0.05 mV) occurred with a significantly higher incidence in the LMCA group (88% [14/16]) than in the LAD (43% [20/46]) or RCA (8% [2/24]) groups. Lead aVR ST segment elevation was significantly higher in the LMCA group (0.16 ± 0.13 mV) than in the LAD group (0.04 ± 0.10 mV). Lead V1ST segment elevation was lower in the LMCA group (0.00 ± 0.21 mV) than in the LAD group (0.14 ± 0.11 mV). The finding of lead aVR ST segment elevation greater than or equal to lead V1ST segment elevation distinguished the LMCA group from the LAD group, with 81% sensitivity, 80% specificity and 81% accuracy. A ST segment shift in lead aVR and the inferior leads distinguished the LMCA group from the RCA group. In acute LMCA obstruction, death occurred more frequently in patients with higher ST segment elevation in lead aVR than in those with less severe elevation.CONCLUSIONSLead aVR ST segment elevation with less ST segment elevation in lead V1is an important predictor of acute LMCA obstruction. In acute LMCA obstruction, lead aVR ST segment elevation also contributes to predicting a patient’s clinical outcome.

Clinical significance of S-T segment elevation in lead aVR in anterior myocardial infarction. Assessment by thallium-201 exercise scintigraphy.

The significance of exercise-induced S-T elevation in aVR was studied in 57 patients with recent anterior infarction and single-vessel disease. S-T elevation in aVR was found at peak exercise in 24 patients. Although the initial defect area was similar in the groups with and without S-T elevation in aVR, the redistribution area was larger in the former group (p < 0.01). When three electrocardiographic criteria were used in the multivariate analysis, S-T elevation in aVR was the significant variable related to redistribution in the anterior wall. Thus, S-T elevation in aVR may indicate ischemia of the anterior wall.