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Background The 2009 electrocardiographic Selvester QRS score for LBBB (2009 LBSS) is prognostic in CRT-patients. Previous studies show limited diagnostic performance in detecting and quantifying left ventricular (LV) scar determined by cardiovascular magnetic resonance imaging (CMR). We aimed to develop an improved method for ECG detection of scar using a large and broadly selected dataset of patients with LBBB. Methods and results We retrospectively identified LBBB patients (n = 325) with available ECG and late gadolinium enhancement (LGE) CMR exams from four centers (142 [44%] with > 0% CMR scar). ECG metrics were measured digitally and semi-automatically, and were compared to CMR-determined scar presence and extent. The 2009 LBSS did not accurately detect or quantify CMR scar (R 2 = 0.04, Area under the Receiver operating characteristic curve [AUC]: 0.60, [95% confidence interval: 0.54–0.66]). Multivariable stepwise logistic regression applied in 44 pre-determined ECG variables resulted in an improved 6-variable ECG model to detect CMR-scar (AUC 0.72 [0.66–0.77]). Furthermore, a single ECG variable (Lead I R/S amplitude ratio) was predictive of both scar presence (AUC 0.71 [0.65–0.77]) and of LV ejection fraction 2 = 0.21) Conclusions The 2009 LBSS does not accurately detect or quantify CMR scar. Extensive comparison of ECG and CMR identified a single ECG measure (lead I R/S amplitude ratio

Primary revascularization (PR) and thrombolytic therapy (TT) reduce infarct size and mortality in patients with ST-segment elevation acute myocardial infarction (AMI). Electrocardiogram methods can determine the extent of myocardial salvage with different AMI therapies by comparing infarct size predicted by initial ST-segment changes and infarct size estimated by later quantitative QRS scores. In a community hospital setting, we used quantitative electrocardiogram methods to estimate infarct size and myocardial salvage associated with TT and PR amongst 50 patients presenting with inferior ST-segment elevation AMI. Baseline and electrocardiogram characteristics did not differ between TT (n = 29) and PR (n = 21) patients. There was no difference in median myocardial salvage (%) between TT vs. PR groups, (38.3% vs. 44.9% respectively, P =.66). Among patients with inferior AMI, myocardial salvage was achieved with both TT and PR therapy and did not differ significantly between reperfusion strategies.

Introduction Calcific aortic stenosis (AS) is a common valvular disease among the elderly. Often, AS leads to left ventricular hypertrophy (LVH) and symptoms of heart failure. Severe AS can be treated by transcatheter aortic valve replacement (TAVR). Previous studies have shown that electrocardiogram (ECG) criteria for LVH correlate poorly with left ventricular mass (LVM) in echocardiography. However, such correlations have not been studied in TAVR patients. Aims To evaluate ECG LVH criteria as a method of diagnosing and quantifying LVH in patients with AS undergoing TAVR. Material and methods Twenty-four patients, with neither pacemaker nor bundle branch block, who had undergone pre-TAVR ECG and echocardiography were included. The ECGs were evaluated using the Sokolow–Lyon, Romhilt–Estes and Cornell Voltage criteria for LVH as well as spatial maximal QRS-T angle and 3D QRS maximal spatial vector. The LVM was measured by echocardiography. Results 15 (63%) patients met the echocardiographic threshold for LVH. 7 patients (29%) were positive by the Sokolow–Lyon, 5 (21%) by the Romhilt–Estes and 12 (50%) by the Cornell Voltage criteria for LVH. There was no correlation between LVM and conventional ECG LVH criteria or spatial parameters. QRS duration correlated with LVM (r=0.56, R 2 =0.31, p=0.005). However, there was no correlation between QRS duration and LVM index or relative wall thickness (RWT). Conclusions In TAVR patients, none of the ECG LVH criteria should be used for evaluation of LVM. QRS duration is moderately correlated to LVM and is the most useful ECG estimate of LVM.

The investigators report the diagnostic performance of the latest version (Version 2.5) of the recently developed Cardiovise algorithm for detecting prior myocardial infarction (MI). The Cardiovise 2.5 prior MI algorithm, a component of Cardiovise Cardiac Diagnostic System (Inovise Medical, Inc, Newberg, OR), uses scalar QRS, scalar T wave, and vectorcardiographic QRS criteria for detecting, sizing, and localizing prior MI. In this study only the detection part of the algorithm's performance was evaluated, using 105 patients with and 98 patients without prior MI as indicated by the results of cardiac imaging with Sestamibi. The specificity, and sensitivity of Cardiovise 2.5 for detecting prior MI in this population of patients are 97% and 79%, respectively. The sensitivity and overall diagnostic performance of Cardiovise 2.5 was significantly better than those of a total of 6 human readers (3 cardiologists and 3 primary care physicians) and to 2 commercially available ECG diagnostic algorithms.

Consideration of increased T wave amplitude (tall T waves), either alone or in association with other electrocardiographic (ECG) parameters, may be beneficial for the early detection of acute transmural ischemia, and quantification of the increase might be used in quantifying the ischemic area. The primary purpose of this study was to quantify normal T wave amplitude limits according to ECG lead, sex, and age. One thousand nine hundred thirty-five subjects in two normal populations were analyzed, and the 98th percentile of the positive T wave amplitude for each ECG lead (including -aVR) was considered the upper limit of normal. Normal T wave amplitude was two times greater in the precordial than in the limb leads, and it was approximately 25% greater in men than in women in all leads. There was approximately a 10% decrease in normal T wave amplitude between 18-39- and 40-59-year-old patients and a 15% decrease between 40-59- and 60-79-year-old patients. The upper limit of normal T wave amplitudes identified in this study confirm those developed by Lepeschkin for use as means for each lead when age and sex are not considered. These limits might be incorporated into both normograms and automated ECG analysis systems to determine the presence or absence of tall T waves in patients presenting with symptoms of acute transmural ischemia.

Purpose: Several ST segment deviation scores have been developed to estimate the myocardial area at risk (AAR) during acute myocardial infarction (AM I), which can be used to measure the effectiveness of reperfusion therapy. The purpose of this study was to assess whether one of these ST segment deviation scores (the Aldrich score) is sufficiently stable between the electrocardiogram (ECG) recorded in the ambulance (ECG I) and the ECG recorded at the time of admission to the hospital (ECG 2) to be used as a baseline estimation of the AAR. Methods: The Aldrich scores were compared between ECG 1 and ECG 2 in 77 patients who met the criteria for ST elevation myocardial infarction. The ECGs had a time interval of at least 5 minutes and were recorded before reperfusion therapy. Sufficiently stable was defined as 95% of the patients did not show a temporal change of the Aldrich score of more than 4.5%. Results: The mean time interval between ECG 1 and ECG 2 was 20 +/- 9 minutes. Forty-three percent of the total study population showed an "unstable Aldrich score" between ECG I and ECG 2. Fifty-seven percent showed a "stable Aldrich score", which means that the 95% standard for sufficiently stable was not fulfilled. By dividing the population based on infarct location, the group with inferior AMI (n = 43) showed more stability (67%) than the group with anterior AMI (n = 34) (44%) (P

Background Electrocardiogram (ECG)-based detection of ischemia is typically dependent on identifying changes in repolarization. Analysis of high-frequency QRS (HFQRS) components, related to the depolarization phase of the cardiac action potential, has been reported to better identify ischemia. Our aim was to test the hypothesis that HFQRS analysis is both more sensitive and specific than standard ECG for detecting exercise-induced ischemia in patients undergoing exercise myocardial perfusion imaging (MPI). Methods Exercise MPI was performed in 133 consecutive patients (age, 63 ± 12; 100 males) and used as the gold standard for ischemia. Patients with QRS duration more than 120 milliseconds (n = 20), technical problems (n = 8), or inconclusive MPI (n = 4) were excluded, leaving 101 patients for analysis. Conventional ECG was combined with high-resolution ECG acquisition that was digitized and analyzed using the HyperQ System (BSP, Tel Aviv, Israel). The relative HFQRS intensity change during exercise was used as an index of ischemia. Results Of the 101 patients who were included in the analysis, 19 exhibited MPI ischemia. The HFQRS index of ischemia was found to be more sensitive (79% vs 41%; P < .05) and more specific (71% vs 57%; P < .05) than conventional ST analysis. Conclusions The HFQRS analysis was more sensitive and specific than conventional ECG interpretation in detecting exercise-induced ischemia and exhibited enhanced diagnostic performance in both women and men. Thus, it may aid in the noninvasive diagnosis of ischemic heart disease.

Background The size of myocardial infarction (MI) is of significance for the prognosis. Selvester scores might be valuable for this estimation. Objective To compare the differences in Selvester scores for chronic MI provided from standard and EASI-derived 12-lead electrocardiograms (ECGs) and to compare these scores to the MI size measured by delayed-enhancement magnetic resonance imaging (DE-MRI). Methods Thirty-seven patients were studied. In connection with their DE-MRI scan follow-up after chest pain, body surface potential mapping was performed. Standard and EASI 12-lead ECGs were constructed from the maps. Two investigators manually performed the measurements required for scoring with the Selvester system using a quad-plot format of the ECGs. One of the investigators repeated this once for the standard leads. Results The differences between the 2 ECG estimations of MRI-measured MI size were not statistically significant. Neither the association nor the agreement between MRI and EASI-lead measurements or between MRI and standard-lead measurements were very strong. Conclusions The differences between ECG and MRI measurements of MI size indicate that both methods may need improvement.

After an acute myocardial infarction (MI), it is important to define the infarct size because it is related to mortality and morbidity. The Selvester QRS Score is an electrocardiographic (ECG) method that has been developed for estimating MI size. It has been shown to correlate well with postmortem anatomically measured sizes of single MI in patients who did not receive thrombolytic therapy. The aim of this study was to test the hypothesis that correlation between Selvester QRS Score-estimated MI size and contrast-enhanced magnetic resonance imaging (ceMRI)-measured MI size is equivalent in patients who did vs those who did not receive thrombolytic therapy.Thirty-six patients with MI (24 with thrombolytic therapy and 12 without) received ceMRI and ECG at admission and at 1 or 6 months after admission. Indeed, in 23 of the patients, the therapy was intravenous only. The Selvester QRS Score was calculated using the 1-month ECG or, if not available, the 6-month ECG. The correlation between the 2 measures of MI size was determined for all patients and for the 2 groups separately.The mean MI size in the group that did not receive thrombolytic therapy was 8.5% +/- 6.4% estimated by the Selvester QRS Score and 11.7% +/- 10.2% measured by ceMRI. For the group that received thrombolytic therapy, Selvester QRS Score was 13.9% +/- 11.1% and ceMRI was 20.2% +/- 11.3%. The mean MI size in both groups combined was 12.1% +/- 10.0% estimated by the Selvester QRS Score and 17.3% +/- 11.5% measured by ceMRI. The Spearman rank correlation coefficient between Selvester QRS Score and ceMRI was 0.74 (P.0001) for all patients, 0.74 (P.0001) for the group that received thrombolytic therapy, and 0.64 (P = .024) for the group that did not receive thrombolytic therapy.The associations between Selvester QRS Score and ceMRI-based MI were statistically significant and similar in both groups.

We tested the hypothesis that paramedic recognition of ST-elevation myocardial infarction (STEMI) and cardiologist activation of the cardiac catheterization laboratory without transmission of the electrocardiogram reduces door-to-balloon times.We studied a consecutive series of patients suspected to have STEMI who were taken to the cardiac catheterization laboratory in the 6-month period before hotline implementation (historical controls) and during the first year of hotline use (intervention group, hotline; emergency medical service patients without hotline, concurrent controls).Emergency medical services activated the hotline 47 times, and 25 patients were subsequently taken to the catheterization laboratory. Patients who received PCI involving hotline use (n = 20) had significantly shorter door-to-balloon times (58 minutes; 25th-75th percentile, 52-73 minutes) than historical controls (n = 15) (112 minutes; 25th-75th percentile, 81-137; P.0001) and concurrent controls (n = 15) (92 minutes; 25th-75th percentile, 76-112; P = .019).Paramedic transtelephonic communication to cardiologist of clinical and electrocardiogram assessment resulted in a 54-minute reduction in door-to-balloon time for patients with STEMI.

Background During acute myocardial infarction, both ST elevation and QRS distortion on the initial electrocardiogram (ECG) have been correlated with poorer prognosis. Studies in dogs and humans suggest that these ECG markers provide information about myocardial protection from both collateral blood flow and ischemic preconditioning. Methods In a protocol designed to precondition the heart with ischemia, we examined both ST-segment elevation and QRS complex prolongation in lead II of the ECG in 23 mongrel dogs during the first and fourth episode of 5 minutes of left circumflex artery occlusion. Myocardial collateral flow was measured during each of these episodes by injection of radioactive microspheres 2.5 minutes into the episode of ischemia. Results During ischemia, the degree of elevation of the ST segments was reduced markedly in hearts preconditioned with ischemia and/or in hearts with the greatest amounts of collateral arterial flow. During the first episode of ischemia, the ST segments increased to a similar extent in severe and moderate ischemia, but less in hearts in which the ischemia was mild. However, marked QRS prolongation was present only in hearts with severe ischemia, and decreased when the hearts were preconditioned. In addition, large ischemic beds exhibited the most marked QRS prolongation, whereas small but even severely ischemic beds showed little or no change in QRS duration. Conclusion Both ST elevation and QRS prolongation are reduced by the presence of collateral flow and ischemic preconditioning. The QRS complex merits further study as an important marker of the degree of myocardial protection during human acute myocardial ischemia/infarction.

The Anderson-Wilkins (AW) electrocardiographic (ECG) acuteness score complements time from pain onset in prognostic stratification of patients with acute myocardial infarction (AMI). However, for the AW acuteness score to be of practical use in the acute situation, it must be an integral component of a commercial automated ECG analysis program. The objective of this study was to determine the concordance between human and computer measurements and calculation of the AW acuteness score. The mean difference in AW acuteness score was 0.11 +/- 0.66 for anterior and -0.07 +/- 1.24 for inferior AMI. Ninety-nine percent of the differences were found to be 1.0 or less for the anterior AMI group, and 91.7% were 1.0 or less in the inferior AMI group. The differences were primarily caused by minor disagreements in measurements. In conclusion, the AW acuteness score established using manual ECG waveform measurements can be implemented into commercial automated ECG analysis programs to achieve practical use in clinical decision support for patients with AMI.