Lead aVL Research Articles

Association of different electrocardiographic patterns with shock index, right ventricle systolic pressure and diameter, and embolic burden score in pulmonary embolism.

Some electrocardiographic (ECG) patterns are characteristic for pulmonary embolism but exact meaning of the different ECG signs are not well known. The aim of this study was to determine the association between four common ECG signs in pulmonary embolism [complete or incomplete right bundle branch block (RBBB), S-waves in the aVL lead, S1Q3T3 sign and negative T-waves in the precordial leads] with shock index (SI), right ventricle diastolic diameter (RVDD) and peak systolic pressure (RVSP) and embolic burden score (EBS). The presence of complete or incomplete RBBB, S waves in aVL lead, S1Q3T3 sign and negative T-waves in the precordial leads were determined at admission ECG in 130 consecutive patients admitted to the intensive care unit of a single tertiary medical center in a 5-year period. Echocardiography examination with measurement of RVDD and RVSP, multidetector computed tomography pulmonary angiography (MDCT-PA) with the calculation of EBS and SI was determined during the admission process. Multivariable regression models were calculated with ECG parameters as independent variables and the mentioned ultrasound, MDCT-PA parameters and SI as dependent variables. The presence of S-waves in the aVL was the only independent predictor of RVDD (F = 39.430, p < 0.001; adjusted R2 = 0.231) and systolic peak right ventricle pressure (F = 29.903, p < 0.001; adjusted R2 = 0.185). Negative T-waves in precordial leads were the only independent predictor for EBS (F = 24.177, p < 0.001; R2 = 0.160). Complete or incomplete RBBB was the independent predictor of SI (F = 20.980, p < 0.001; adjusted R2 = 0.134). In patients with pulmonary embolism different ECG patterns at admission correlate with different clinical, ultrasound and MDCT-PA parameters. RBBB is associated with shock, Swave in the aVL is associated with right ventricle pressure and negative T-waves with the thrombus burden in the pulmonary tree.

A Six Lead Electrocardiogram of Trypanosoma Brucei Infected Dogs

The cardiac function of dogs experimentally infected with Trypanosoma brucei infection was studied electrocardiographically. Ten mongrel dogs clinically free of cardiac abnormalities were used for the study. They were intra-peritoneally inoculated with 1 ml of Phosphate buffered saline diluted blood containing 1x106 of the federe strain of the parasite. A six lead electrocardiogram was taken in each of the dogs before and at 8th 16th and 24th days after inoculation of the parasites. Ventricular premature contraction, Atrio-ventricular blocks, polymorphic ventricular tachycardia, notched R wave, ST wave abnormalities and sinoventricular rhythm were displayed by the infected dogs. The infected dogs had elevated heart rate in all the six leads studied. At various times during the infection, QT and QTC of the infected dogs were significantly lower than the uninfected ones in leads II and AVF. At various days during the infection the QRS index was significantly wider than those of the uninfected dogs. T. brucei infected dogs have a lower variability of their RR index when compared to the uninfected ones. The R wave voltage was significantly reduced and T wave amplitude was significantly increased by the infection in lead AVL and lead I respectively. The result of this study has shown that T. brucei caused arrhythmia and ECG changes in dogs. The increased heart rate, reduced RR variability, and the shortened QT and QTC width seen during the infection reflects the enhanced state of the sympathetic activity in the infected dogs.

PREdiction of ST deviations in lead aVR as a noninvasive tool to predict the infarct-Related coronary artery in patients with acute Inferior-wall Myocardial Infarction (The PREST-RIMI Study)

Background: Acute myocardial infarction is one of the most common presentations of coronary artery disease (CAD). Although coronary angiography remains the gold standard for identification of the infarctrelated artery (IRA), conventional 12-lead electrocardiography (ECG) is an essential tool for diagnosis, risk stratification and prognosis. If specific ECG patterns can be recognized, it will be possible to determine the IRA and size of the ventricular area that is jeopardized. The existing ECG algorithms have good sensitivity for the right coronary artery (RCA) and good specificity for the left circumflex artery (LCx) as predictors of IRA in patients with acute inferior-wall myocardial infarction (IWMI), while the specificity for the RCA and sensitivity for the LCx are modest. OBJECTIVE: To evaluate deviations in lead aVR to predict IRA in patients with IWMI, and to validate several commonly used 12-lead ECG characteristics. Methods: A total of 585 consecutive patients with a first occurrence of acute IWMI were analyzed for the association between ECG and IRA diagnosed using coronary angiography. Subsequently, the sensitivity, specificity, positive predictive value, negative predictive value and accuracy of depression in lead aVR, along with various commonly used ECG criteria for predicting the IRA, were estimated using coronary angiographic findings as the gold standard. Results : The RCA and the LCx were found to be the IRA in 415 (71%) and 170 (29%) patients, respectively. It was observed that the absence of ST depression in lead aVR, ST depression in lead I ≥0.5 mm, ST depression in lead aVL >1 mm and ST elevation in lead III > ST elevation in lead II had excellent sensitivity and specificity in predicting the RCA as the culprit vessel. Similarly, ST depression in lead aVR ≥0.5 mm, the ratio of ST depression in lead V3 to ST elevation in lead III >1.2 had excellent sensitivity and specificity in predicting the LCx as the culprit vessel. Conclusion: These findings reveal that evaluation of ST deviations in lead aVR offers good sensitivity and specificity for LCx and RCA occlusions. The authors believe that using multiple ECG criteria may provide earlier and better identification of the IRA.

A Vector-Based Algorithm to Differentiate Septal and Free Wall Sites of Origin of Ventricular Arrhythmias in the Right Ventricular Outflow Tract

Purposes: There are few vector-based electrocardiogram (ECG) algorithms to differentiate ventricular tachycardia (VT) and premature ventricular complexes (PVCs) originating from the septum (SP) or free wall (FW) in the right ventricular outflow tract (RVOT). Methods: One hundred and twenty-one patients (mean age 41 ± 13 years; 62% female) underwent mapping and ablation of symptomatic PVC or VT with left bundle branch block morphology. Inferior axis and precordial lead transition zone ≥V3 on the ECG were analyzed retrospectively. Ablation was highly successful on the 95 SP patients and among 26 cases in the FW group. The ECG morphology of VT/PVC was analyzed to derive a novel algorithm to localize VT origin within the RVOT. A VT/PVC QRS axis ≥90° or an R wave amplitude ratios ≥1 in leads II and III predicted a septal origin. If neither of these characteristics were present, the following criteria were each given a score of 1: VT/PVC QRS axis <85;°, leads II and III R wave amplitude ratio <0;.88, QRS duration in lead III ≥155 ms, and QRS duration ≥155 ms in lead aVL. A cumulative score of ≥2 predicted an FW origin whereas a total score of <2; predicted an SP origin. A prospective analysis in 99 patients was used to confirm the significance of the algorithm. Results: Retrospective analysis showed that the new algorithm predicted an SP origin with an overall sensitivity, specificity, and positive predictive values of 95.2%, 88%, and 96.3%, respectively. Prospective analysis showed that the new algorithm predicted RVOT-SP origin with a sensitivity, specificity, and positive predictive values of 97.5%, 88.9%, and 97.5%, respectively. Conclusion: The new vector-based ECG algorithm can differentiate septal from FW sites of origin in the RVOT with a high sensitivity, specificity, and positive predictive values.

Electrocardiographic characteristics of idiopathic premature ventricular contractions originating from the junction of the right ventricular outflow tract and tricuspid annulus

AimsThe right ventricular outflow tract (RVOT) and tricuspid annulus (TA) are common origins for idiopathic PVCs from the right ventricle. We sought to clarify the characteristics of a subgroup of idiopathic PVCs originating from the RVOT–TA junction. Methods and resultsSurface ECG and intra-cardiac electrophysiological characteristics were analyzed in 101 patients with frequent PVCs who underwent successful RFCA in the right ventricle. Pacing was performed in the right ventricle in another 5 control subjects. The origin of PVCs determined by the successful ablation site was at the RVOT, the TA and the RVOT–TA junction in 78, 11 and 12 patients, respectively. The PVCs originating from RVOT–TA junction showed a monophasic R wave in leads I, II, III and aVF and a flat QRS complex in lead aVL. A flat QRS complex (rsr′, qs, qr, rs or r pattern, mean r or qs amplitude, 0.3±0.1mV) in lead aVL distinguished the RVOT–TA junction origin from the RVOT (deep negative, −0.7±0.4mV) and the TA (tall positive, 0.8±0.3mV) origins. Activation mapping and pace mapping strategies were successfully applied to localize this specific origin of the PVCs. Pacing at the RVOT–TA junction in the control subjects validated a flat QRS complex in lead aVL. ConclusionWe report for the first time that the RVOT–TA junction is a non-rare but distinct origin of right ventricular PVCs. The flat QRS complex in lead aVL distinguishes this origin from RVOT and TA. RFCA is highly effective for eliminating PVCs in this origin.

ST depression in lead aVL differentiates inferior ST-elevation myocardial infarction from pericarditis

BackgroundST-segment elevation (STE) due to inferior STE myocardial infarction (STEMI) may be misdiagnosed as pericarditis. Conversely, this less life-threatening etiology of ST elevation may be confused for inferior STEMI.We sought to determine if the presence of any ST-segment depression in lead aVL would differentiate inferior STEMI from pericarditis. MethodsRetrospective study of 3 populations. Cohort 1 included patients coded as inferior STEMI, cohort 2 included patients with a discharge diagnosis of pericarditis who presented with chest pain and at least 0.5 mm of ST elevation in at least 1 inferior lead. We analyzed the presenting electrocardiogram in both populations, with careful assessment of leads II, III, aVF, and aVL. In addition, we retrospectively studied a third cohort of patients with subtle inferior STEMI (<1-mm STE with occluded artery on catheterization) and assessed the sensitivity of ST depression in lead aVL for this group. ResultsOf 154 inferior STEMI patients, 154 had some amount of ST depression in lead aVL (100%; confidence interval, 98%-100%). Of the 49 electrocardiograms in the pericarditis group, all 49 had some inferior STE but none had any ST-segment depression in lead aVL (specificity, 100%; confidence interval, 91%-100%). In the third cohort, there were 272 inferior MIs with coronary occlusion, of which 54 were “subtle.” Of these, 49 had some ST depression in lead aVL. ConclusionWhen there is inferior ST-segment elevation, the presence of any ST depression in lead aVL is highly sensitive for coronary occlusion in inferior myocardial infarction and very specific for differentiating inferior myocardial infarction from pericarditis.

Myocardial Infarction with Ventricular Septal Rupture and Cardiogenic Shock

A 72-year-old woman with a history of systemic arterial hypertension presented to the emergency department with chest pain, and an electrocardiogram showed acute anterior myocardial infarction with striking ST-segment elevation, upright T waves, and large Q waves in leads V1 to V4 (Figure). Furthermore, the ST-segment elevation > 0.25 mV in lead V1, the ST depression ≥ 0.1 mV in lead III, and the ST elevation ≥ 0.1 mV in lead aVL indicated that the left anterior descending coronary artery was occluded proximal to both the first major septal perforating branch and the first diagonal branch (1–4). Figure. Electrocardiogram recorded on the patient's arrival in the emergency department. See text for explication. Also, note that there was sinus rhythm at a rate of 106 beats/min with the next to last QRS complex being a fusion of a premature ventricular complex ... Anterior infarcts from such proximal left anterior descending occlusions tend to be quite large and are often associated with cardiogenic shock (2, 4, 5), which this woman manifested soon after her arrival in the emergency department. An echocardiogram showed a left ventricular ejection fraction of approximately 40% with akinesis of the apex and distal two-thirds of the ventricular septum. The right ventricle was considerably dilated. Through a defect in the distal ventricular septum, blood shunted from left to right during systole with reversal of flow during diastole, suggesting an elevated right ventricular diastolic pressure. Laboratory studies of the patient's blood confirmed myocardial damage and indicated chronic kidney disease and acute metabolic acidosis (Table). Table. Laboratory results from blood drawn on admission The patient had a run of ventricular tachycardia while in the emergency department. Once stable, she was transported to the cardiac catheterization laboratory; an intra-aortic balloon was placed via the left femoral artery, and 1:1 counterpulsation was begun. Coronary arteriography, performed via the right femoral artery, showed proximal total occlusion of the left anterior descending coronary artery, diffuse disease of the left circumflex coronary artery with a totally occluded first obtuse marginal branch and 90% narrowing of the third obtuse marginal branch, and diffuse disease of the right coronary artery with a long 80% to 90% narrowing in its mid segment. Despite repeated inflations of first a 2.5 × 20 mm balloon and then a 2.0 × 25 mm balloon in the proximal and distal portions of the left anterior descending artery, there was no flow. Hypotension, bradycardia, and acidosis (arterial blood pH = 6.9; reference = 7.4) were temporarily combated with atropine, epinephrine, and sodium bicarbonate, and the patient was sent to the intensive care unit with an intravenous dopamine infusion and 1:1 intra-aortic balloon counterpulsation. She died several hours later. Ventricular septal rupture formerly occurred in 1% to 3% of patients with acute myocardial infarction and did so within the first week in more than 75% of them (6). Subsequently, among patients treated with fibrinolysis, the incidence of ventricular septal rupture was only 0.2%, and the median time from the onset of the infarct was 1 day (7). Approximately one-half of ventricular septal ruptures are in the setting of an anterior infarct, and one-half occur in patients with inferior infarcts (8, 9). At least two-thirds of patients with myocardial infarction and ventricular septal rupture die, and many of these, like our patient, are older and have cardiogenic shock; early operation by superb surgeons seems to improve the chances of survival (10). The large upright fused ST segments and T waves seen in the figure have been referred to as “tombstoning,” probably because of the appearance of tombstones and because they are signs of more extensive myocardial damage and of a poor prognosis (11). Sclarovsky believes that this pattern of deep anterior Q waves with persistently elevated ST segments and tall T waves indicates lack of reperfusion of the myocardium due to a severely damaged microcirculation (12).

Value of electrocardiogram (ECG) in identifying acute occlusion sites of right coronary artery

Clinical data of 151 patients with acute occlusion of right coronary artery were retrospectively analyzed. Coronary angiography and electrocardiography (EEG) were performed in all 151 patients, angiography showed proximal-middle segment occlusion in 114 cases and distant segment occlusion in 37 cases. The correlation of ECG findings with coronary artery occlusion sites was analyzed. Results showed that EEG findings related to proximal-middle segment occlusion were: ST segment elevation in lead V4R ≥0.05 mV, Ⅲ degree atrioventricular block, ST segment depression in lead Ⅰ>0.1 mV, ST segment depression in lead AVL≥0.2 mV, ST segment elevation in lead Ⅲ≥0.25 mV, the total ST depression in lead V2,V3 and V4 ≥0.4 mV , the total ST depression in lead I and aVL ≥0.25 mV; among which ST depression of Lead Ⅰ>0.1 mV, ST elevation of Lead V4R≥0.05 mV and Ⅲ degree atrioventricular block were used to predict occlusion of proximal-middle segment of right coronary artery with 100% specificity. ECG findings related to distal segment occlusion were: ST depression in lead Ⅰ≤0.1 mV, ST segment depression in lead AVL<0.2 mV, ST elevation in lead Ⅲ≤0.25 mV, the total ST depression in lead V2,V3 and V4 <0.4 mV, ST segment were not depression in lead V1-V5,the total ST depression in lead I and aVL<0.25 mV. Based on a 4-step flow method, ECG might be adopted to identify the acute occlusion sites in proximal-middle segment and distal segment of right coronary. Key words: Coronary occlusion; Inferior wall myocardial infarction; Electrocardiography

Focal atrial tachycardia surrounding the anterior septum: strategy for mapping and catheter ablation.

Background—Focal atrial tachycardias (ATs) surrounding the anterior atrial septum (AAS) have been successfully ablated from the right atrial septum (RAS), the aortic cusps, and the aortic mitral junction. However, the strategy for mapping and ablation of AAS-ATs has not been well defined.Methods and Results—Of 227 consecutive patients with AT, 47 (20.7%; mean age, 56.3±11.6 years) with AAS-ATs were studied; among them, initial ablation was successful at RAS in only 5 of 14 patients and at noncoronary cusp (NCC) in 28 of 33 patients. In 45 of the 47 patients, the 46 of 48 AAS-ATs were eliminated at RAS in 8 patients, NCC in 35 patients (earliest activation time at NCC was later than that at RAS by 5–10 ms in 6 patients), and aortic mitral junction in 3 patients (all with negative P wave in lead aVL and positive P wave in the inferior leads), including 1 patient whose 2 ATs were eliminated separately from the NCC and the aortic mitral junction.Conclusions—Most of the ATs surrounding the AAS can be eliminated from within the NCC, which is usually the preferential ablation site. Ablation at the RAS and aortic mitral junction should be considered when supported by P-wave morphologies on surface ECG and results of activation mapping and ablation.

R Wave in aVL Lead is a Robust Index of Left Ventricular Hypertrophy: A Cardiac MRI Study.

In patients free from overt cardiac disease, R wave in aVL lead (RaVL) is strongly correlated with left ventricular mass index (LVMI) assessed by transthoracic echocardiography. The aim of the present study was to extend this finding to other settings (cardiomyopathy or conduction disorders), by comparing ECG criteria of left ventricular hypertrophy (LVH) to cardiac MRI (CMR). In 501 patients, CMR and ECG were performed within a median-period of 5 days. CMR LVH cut-offs used were 83 g/m2 in men and 67 g/m2 in women. RaVL was independently correlated with LVMI in patients with or without myocardial infarction (MI) (N = 300 and N = 201, respectively). SV3 was independently correlated with LVMI and LV enlargement only in patients without MI. In the whole cohort, RaVL had area under receiver-operating characteristic curve of 0.729 (specificity 98.3%, sensitivity 19.6%, optimal cut-off 1.1 mV). The performance of RaVL was remarkable in women, in Caucasians, and in the presence of right bundle branch block. It decreased in case of MI. Overall, it is proposed that below 0.5 mV and above 1.0 mV, RaVL is sufficient to exclude or establish LVH. Between 0.5 and 1 mV, composite indices (Cornell voltage or product) should be used. Using this algorithm allowed classifying appropriately 85% of the patients. Our results showed that RaVL is a good index of LVH with a univocal threshold of 1.0 mV in various clinical conditions. SV3 may be combined to RaVL in some conditions, namely LV enlargement to increase its performance.

Isolated T Wave Inversion in Lead aVL: An ECG Survey and a Case Report.

Background. Computerized electrocardiogram (ECG) analysis has been of tremendous help for noncardiologists, but can we rely on it? The importance of ST depression and T wave inversions in lead aVL has not been emphasized and not well recognized across all specialties. Objective. This study's goal was to analyze if there is a discrepancy of interpretation by physicians from different specialties and a computer-generated ECG reading in regard to a TWI in lead aVL. Methods. In this multidisciplinary prospective study, a single ECG with isolated TWI in lead aVL that was interpreted by the computer as normal was given to all participants to interpret in writing. The readings by all physicians were compared by level of education and by specialty to one another and to the computer interpretation. Results. A total of 191 physicians participated in the study. Of the 191 physicians 48 (25.1%) identified and 143 (74.9%) did not identify the isolated TWI in lead aVL. Conclusion. Our study demonstrated that 74.9% did not recognize the abnormality. New and subtle ECG findings should be emphasized in their training so as not to miss significant findings that could cause morbidity and mortality.

Clinical Implication of ST Segment Depression in aVR &amp;amp; aVL in Patients with Acute Inferior Wall Myocardial Infarction

Objectives: The aim of the study was to assess the role of ST segment depression in the limb leads aVR and aVL for the diagnosis of acute posterior wall infarction and the identification of infarct related artery (IRA) in patients with acute inferior wall MI. Methods: In 159 patients with I-STEMI, 127 (80%) had RCA occlusion and 32 (20%) had LCX occlusion. In the ECG algorithms, RCA occlusion was indicated by ST depression in lead aVL higher than lead aVR and no ST depression in lead aVL and aVR. LCX occlusion was indicated by ST depression in lead aVR higher than or equal to lead aVL and no ST depression in aVL and aVR. Results: The sensitivity, specificity, positive and negative predictive values of these algorithms were high (98%, 82%, 92% and 95% for RCA occlusion and 83%, 98%, 95% and 92% for LCX occlusion). Conclusion: The ECG algorithms can reliably identify the culprit artery in I-STEMI. ST segment depression in limb leads aVR and aVL with avR ≥ aVL helps to diagnose left circumflex artery as a culprit IRA in an acute inferior wall MI.

0352: R wave in AVL lead is a robust index of left ventricular hypertrophy: a cardiac MRI study

in patient free from overt cardiac disease and conduction disorders, R wave in aVL lead (RaVL) is better correlated than other ECG indexes with left ventricular mass index (LVMI) assessed with transthoracic echocardiography. The aim of this study was to validate RaVL as an index of left ventricular hypertrophy (LVH) using cardiac MRI (CMR) in different conditions. In a cohort of 501 patients, CMR and ECG were performed within a median-period of 5 days. The CMR LVH cut-offs used were 83g/m 2 in men and 67g/m 2 in women. In mutivariable analysis (adjusted for age, left ventricular volume, blood pressure, age and gender), RaVL was correlated with LVMI in the whole cohort and also in patients with or without myocardial infarction (MI): β=0.037, p<0.001; β=0.053, p<0.001; β=0.039, p=0.010, respectively. In the whole cohort, area under ROC curve (AUC) was 0.729 (specificity 98.3%, sensitivity 19.6%, optimal cut-off 1.1 mV, 75.8% correctly classified). In the subgroup without MI (N=300), an optimal value of 1.0 mV classified correctly 80.7% of patients (AUC 0.781, specificity 95.5%, sensitivity 35.5%). In the subgroup with MI (N=201), RaVL had a lower diagnostic performance (AUC 0.673, specificity 97.7%, sensitivity 13.2%, optimal threshold 1.1 mV). We observed the same diagnostic performance of RaVL in women and in men without MI (optimal threshold 1.0 mV, AUC 0.788 and 0.778 respectively).The diagnostic value of RaVL was lower in patients with left bundle branch block (BBB) or left deviation axis in comparison with those having right BBB (optimal threshold 1.0 mV for all, AUC 0.556, 0.753 and 0.933 respectively). Using the gold standard to assess LVMI, our results demonstrated thar RaVL is a good index of LVH with a threshold around 1.0 mV independently of various clinical conditions.

R wave in aVL lead: an outstanding ECG index in hypertension.

The voltage of R wave in lead aVL (RaVL) seems to be more tightly correlated with left ventricular mass and cardiovascular events than any other ECG criterium of left ventricular hypertrophy. We hypothesized that RaVL could be an independent predictor of all-cause and cardiovascular death in hypertensive individuals. The baseline clinical and biological variables as well as ECG recordings were analyzed in a prospective cohort of 589 hypertensive individuals. After 10 years of follow-up, we observed 95 deaths of which 53 had a cardiovascular cause. The optimal RaVL voltages to predict all-cause and cardiovascular mortality were 0.8 and 0.6 mV, respectively. In a multivariate adjusted Cox model, having an RaVL voltage superior to these cutoffs was associated with increased risks of all-cause death [hazard ratio: 2.04, 95% confidence interval (CI): (1.30-3.22)] and of cardiovascular death [hazard ratio: 2.89, 95% CI: (1.47-5.68)]. In the whole cohort and with the same adjusted Cox regression model, each 0.1 mV increment would increase the risk of all-cause death by 1.07 times [95% CI: (1.02-1.12)] and that of cardiovascular death by 1.13 times [95% CI: (1.06-1.20)]. After excluding in turn patients with positive Sokolow index, Cornell voltage, or Cornell product, the results remained statistically significant, meaning that RaVL was still able to pick-up high-risk patients when other classical and more sophisticated indices were not observable. The present results strengthen previous reports that demonstrated a strong role of RaVL voltage in risk stratification in hypertension.

Usefulness of QRS Voltage Correction by Body Mass Index to Improve Electrocardiographic Detection of Left Ventricular Hypertrophy in Patients With Systemic Hypertension

Obesity reduces the accuracy of voltage-based electrocardiographic (ECG) criteria for diagnosis of left ventricular (LV) hypertrophy. We developed a new ECG score for diagnosis of LV hypertrophy, defined either by a typical strain pattern or a product of the Cornell voltage (R wave height in lead aVL plus S wave depth in lead V3) by body mass index >604mm∙kg/m(2). We examined a population of 2,747 untreated hypertensive subjects (mean age 49 ± 11 years) with good quality ECG and echocardiographic tracings. Several traditional ECG criteria for LV hypertrophy were compared with the new score, with echocardiographic LV mass taken as reference. Among the tested criteria, the highest sensitivity combined with specificity was yielded by the new score (sensitivity 36.1%, 95% confidence interval [CI] 32.9 to 39.4; specificity 90.5%, 95% CI 89.1 to 91.8; and accuracy 73.1%, 95% CI 71.5 to 74.8). Prevalence of ECG LV hypertrophy with the new score was 18%. On the basis of comparisons between areas under the receiver operating characteristic curves, the best performance was achieved by the new score with respect to other ECG criteria for LV hypertrophy (all p <0.0001). In conclusion, correction of Cornell voltage by body mass index as a marker of obesity improves the performance of traditional electrocardiography for diagnosis of LV hypertrophy in patients with hypertension.

Dénervation rénale dans le traitement de l’hypertension artérielle résistante : expérience du CHU de Lyon

AimWe report the first experience of Lyon's university hospital regarding renal denervation to treat patients with resistant essential hypertension. Patients and methodsOver a one-year period, 17 patients were treated (12 men, 5 women) with renal denervation. Baseline characteristics were as follows: age 56.5±11.5 years, BMI 33±5kg/m2 and ambulatory blood pressure 157±16/87±13mmHg with 4.2±1.5 anti-hypertensive treatment. ResultsWe did not observe per procedural and early complications. After a median follow-up of 3 months and with the same anti-hypertensive treatment, office systolic blood pressure (SBP) and diastolic blood pressure (DBP) decrease respectively of 20±15 (P<0.001) and 10±13mmHg (P=0.014) (n=17). After six months of follow-up, ambulatory blood pressure (ABPM) decrease of 17.5±14.9mmHg (P=0.027) for SBP and of 10.5±9.6mmHg (P=0.029) for DBP (n=6). Among these patients, five of them were controlled (ABPM inferior to 130/80mmHg) and electrical left ventricular hypertrophy indexes decreased: R wave in aVL lead of 4±3mm (P=0.031), Sokolow index of 3±3mm (P=0.205), Cornell voltage criterion of 9±7mm (P=0.027) and Cornell product of 1310±1104 (P=0.027). ConclusionOur results are in accordance with data from other centers. On average blood pressure decreases significantly but important inter individual variations are observed. The procedure seems safe.

Lead aVL on electrocardiogram: emerging as important lead in early diagnosis of myocardial infarction?

Although a diagnosis of acute myocardial infarction (AMI) that mandates emergency reperfusion therapy requires ST-segment elevation greater than 1 mm in at least 2 contiguous leads, some of the early electrocardiogram (ECG) changes of AMI can be subtle. Any ST-segment depression or T-wave inversion in lead aVL may be implicated in left anterior descending artery lesion or early reciprocal changes of inferior wall myocardial infarction, particularly when the clinical context suggests ischemia. Early recognition of reciprocal changes and serial ECG help initiate early appropriate intervention. Heightened awareness of ST segment and T-wave changes in lead aVL is of paramount importance to quickly identifying life-threatening condition.

Electrocardiographic characteristics of premature ventricular contractions in subjects with type 1 pattern of Brugada syndrome

BackgroundThe ECG characteristics of premature ventricular contractions (PVCs) in subjects with Brugada syndrome (BrS) phenotype were investigated. Methods and resultsA total of 96 patients with type 1 ECG pattern of BrS were screened for PVCs. The study population consisted of 10 male individuals (mean age 41.9±5.6years) with spontaneous (n=2) or drug-induced (n=8) type 1 ECG phenotype of BrS and PVCs. Twenty patients (11 males, age 44.6±15.1years) with idiopathic right ventricular outflow tract (RVOT) PVCs (LBBB/inferior axis morphology with a negative QRS complex in lead aVL) successfully ablated from an endocardial site were also included in the study, and served as comparative controls. Six subjects with BrS phenotype (five during drug challenge) displayed PVCs with LBBB/inferior axis morphology and negative QRS complex in aVL lead which indicates an RVOT origin. The ECG characteristics of PVCs with LBBB/inferior axis in subjects with BrS and idiopathic RVOT arrhythmia were subsequently compared. QRS duration in inferior (p=0.001) and right precordial leads (p<0.001) was significantly longer in subjects with BrS phenotype. The RS interval in lead V2 was also significantly prolonged in individuals with BrS phenotype (p=0.016). Subjects with BrS phenotype exhibited an increased intrinsicoid deflection time measured in right precordial leads compared to those with idiopathic RVOT PVCs (46.0±7.6 vs. 27.2±9.5ms, p<0.001). Finally, a pseudo-delta wave in precordial leads was more commonly observed in subjects with BrS ECG pattern (p=0.029). ConclusionsPVCs in BrS usually originate from the RVOT and display specific ECG characteristics that might be indicative of an epicardial origin. The prolonged interval criteria may be related to a localized epicardial conduction delay.

Chest pain associated with rate-related left bundle branch block and cardiac memory mimicking ischemia

BackgroundIntermittent left bundle branch block (LBBB) has been linked to chest pain, and causes cardiac memory electrocardiographic (ECG) changes mimicking ischemia. PurposeTo present a case of chest pain with ECG abnormalities suggestive of ischemia, both likely caused by LBBB. CaseA 33-year-old hypertensive female evaluated for chest pain and LBBB by ECG was treated with lisinopril and metoprolol, and scheduled for stress testing. A 12-lead ECG performed prior to the stress test, due to recurrence of the chest pain the preceding night, showed resolution of the LBBB with a lower heart rate, and T-wave inversions in the precordial leads suggestive of ischemia. She developed chest pains with reappearance of LBBB during stress testing, which prompted cardiac catheterization. This revealed normal coronaries and left ventricular systolic function. The ECG abnormalities were in retrospect likely due to cardiac memory. Her chest pains may have been caused by the intermittent, rate-related LBBB, as control of her heart rate and blood pressure with metoprolol and lisinopril improved her symptoms on follow-up. ConclusionIntermittent LBBB causes chest pain and electrocardiographic abnormalities suggestive of ischemia in the absence of obstructive coronary disease. Certain clinical and electrocardiographic features may provide clues to a non-ischemic etiology.<Learning objective: In the absence of obstructive coronary disease, rate-related left bundle branch block is associated with chest pain described as local, non-radiating, with palpitations and walk-through phenomenon. It can also cause electrocardiographic (ECG) changes of cardiac memory, which mimic myocardial ischemia, but with T waves that are positive in lead aVL, positive or isoelectric in lead I, and more inverted in the precordial leads compared with lead III. These clinical and ECG features may provide clues to non-coronary etiology of chest pain.>

Instabile Angina pectoris: Zusammenspiel von epikardialer Stenose und Prinzmetal-Spasmus

A 61-year-old man presented with recurrent angina pectoris at rest for 3 days. The medical history revealed hypertension and an elevated cholesterol level as cardiovascular risk factors. The physical examination revealed no pathological findings. ECG at admission showed no signs of ischemia, while high-sensitive Troponin T was slightly elevated. Echocardiography showed diastolic dysfunction and biatrial dilatation. During another episode of angina at rest, ECG showed T-wave inversion in lead aVL. Therefore, coronary angiography was performed. At the beginning of the examination the patient complained of angina at rest and ECG showed ST-elevation in the inferior leads. Coronary angiography revealed a subtotal stenosis in the middle part of the RCA. After intracoronary nitroglycerin injection there was a high-grade stenosis in this region. An intracoronary acetycholin provocation test was performed which reproduced a focal spasm in the area of the RCA stenosis with simultaneous changes in the ECG and reproduction of the patient's unusual angina. After implantation of a bare metal stent a subsequent ACH-test did not elicit any further coronary spasm. Four weeks after the procedure the patient had no further complaints under medical treatment. This case illustrates a patient with a focal Prinzmetal-type spasm with ST-elevation on top of a high-grade stenosis of the right coronary artery as an explanation for the unstable angina. Coronary spasm of the Prinzmetal-type can occur in vessels with epicardial stenosis as well as in vessels without stenosis. In some cases focal coronary spasm can be prevented by the implantation of a stent.