Value of the 12-lead electrocardiogram at hospital admission in the diagnosis of pulmonary embolism

Significance of dynamic changes in the fragmented QRS complex in acute pulmonary embolism

BACKGROUND

Dynamic changes in the fQRS complex between the initial and follow-up ECG in patients with acute pulmonary embolism (APE) have rarely been studied.

OBJECTIVE

The purpose of this study was to investigate the significance of dynamic changes in the fragmented QRS complex in APE patients.

METHODS

APE patients (n = 222) were divided into three groups based on their ECG data to determine whether there were dynamic changes in the fQRS complex from admission to follow-up at one month: the fQRS shallower group (n = 49), fQRS deeper group (n = 25) and fQRS unchanged group (n = 148). Each patient was observed and followed for 12 months.

RESULTS

Cox multivariate logistic regression analysis indicated that the dynamic deeper fQRS complex was an independent predictor of long-term mortality (HR: 5.563, 95 % CI: 1.079-28.678, P = 0.040) in patients with APE. Kaplan-Meier curve analysis revealed that the event-free survival of the fQRS shallower group significantly increased relative to that of the fQRS deeper group and that of the fQRS deeper group significantly decreased relative to that of the fQRS unchanged group and shallower group (P = 0.022, P = 0.041).

CONCLUSION

Compared with the deeper fQRS complex, the dynamic shallower fQRS complex was an indicator of a good prognosis in APE patients, while the dynamic deeper fQRS complex indicated a poor prognosis. Dynamical changes in fQRS may assist clinicians in risk stratification and individualized treatment for APE, as well as in predicting APE regression or progression.

Differentiating electrocardiographic indications of massive and submassive pulmonary embolism: A cross-sectional study in Southern Iran from 2015 to 2020

BACKGROUND

Although using electrocardiogram (ECG) for pulmonary embolism (PE) risk stratification has shown mixed results, it is currently used as supplementary evidence in risk stratification. This cross-sectional study aimed to assess and compare ECG findings of massive and submassive PE versus segmental PE.

METHODS

This cross-sectional study included 250 hospitalized patients with a confirmed diagnosis of acute PE from 2015 to 2020 in Southern Iran. Demographic variables, clinical data, troponin levels, on-admission ECG findings, echocardiography findings, and ECG findings 24 h after receiving anticoagulants or thrombolytics were extracted.

RESULTS

Patients diagnosed with submassive or massive PE exhibited significantly higher rates of right axis deviation (p = .010), abnormal ST segment (p < .0001), S1Q3T3 pattern (p < .0001), inverted T wave in leads V1-V3 (p < .0001), inverted T wave in leads V4-V6 (p < .0001), and inverted T wave in leads V1-V6 (p < .0001). In a multivariable model, inverted T wave in leads V1-V3, inverted T wave in leads V4-V6, pulse rate, and positive troponin test were the statistically independent variables for predicting submassive or massive PE. Furthermore, inverted T wave in leads V1-V3 (sensitivity: 85%, specificity: 95%, accuracy: 93%, AUC: 0.902) and troponin levels (sensitivity: 72%, specificity: 86%, accuracy: 83%, AUC: 0.792) demonstrated the best diagnostic test performance for discriminating submassive or massive PE from segmental PE.

CONCLUSION

In addition to clinical rules, ECG can serve as an ancillary tool for assessing more invasive testing and earlier aggressive treatments among patients with PE, as it can provide valuable information for the diagnosis and risk stratification of submassive or massive PE.

The impact of right bundle branch block and SIQIII-type patterns in determining risk levels in acute pulmonary embolism

Background: Electrocardiography (ECG) findings in acute pulmonary embolism (PE) are known to be related to various right ventricular (RV) alterations. These abnormalities are not included in risk stratification algorithms despite emerging evidence of their association with patient outcomes. We aimed to analyze the impact of right bundle branch block (RBBB) and/or SIQIII patterns as indicators for determining the level of risk in patients with PE. Methods: We performed a retrospective cohort study including all patients with confirmed acute PE hospitalized from January 2008 to December 2019 in two tertiary care cardiology departments. The first ECG taken at admission was selected and the analysis focused on the presence of a complete or an incomplete RBBB and SIQIII-type patterns. Results: A total of 255 patients were divided into two groups: Group I (47.8%, n=122) included patients with PE without RBBB nor SIQIII patterns, and Group II (52.2%, n=133) included patients with RBBB and/or SIQIII patterns. Patients in group II presented significantly more frequently with acute right heart symptoms (45.1% vs. 18%, p<0.001) and cardiogenic shock at admission (31.6 vs. 4.1%, p<0.001). Echocardiographic parameters indicating right heart injury also occurred more significantly in group II patients (p<0.001). By univariate analysis, patients in group II were found to be significantly associated with in-hospital mortality (22.6 vs. 6.1%, p=0.002) and major cardiovascular events (MACEs) during hospitalization (43.3 vs. 13.7%, p<0.001). Multivariate logistic regression analysis identified five independent factors predictive of MACEs: SIQIII and/or RBBB, renal failure, positive troponin levels, RV dysfunction and right heart failure symptoms during initial presentation. Kaplan-Meier survival analysis identified the inclusion in Group II and the presence of SIQIII pattern as predictors of overall mortality (p<0.001). Conclusions: Our study suggests an important and independent prognostic value of RBBB and SIQIII patterns and their usefulness in determining the outcome of PE patients.

The spatial ventricular gradient is associated with adverse outcomes in acute pulmonary embolism

BACKGROUND

The spatial ventricular gradient (SVG) is a vectorcardiographic measurement that reflects cardiac loading conditions via electromechanical coupling.

OBJECTIVES

We hypothesized that the SVG is correlated with right ventricular (RV) strain and is prognostic of adverse events in patients with acute pulmonary embolism (PE).

METHODS

Retrospective, single-center study of patients with acute PE. Electrocardiogram (ECG), imaging, and outcome data were obtained. SVG components were regressed on tricuspid annular plane systolic excursion (TAPSE), qualitative RV dysfunction, and RV/left ventricular (LV) ratio. Odds of adverse outcomes (30-day mortality, vasopressor requirement, or advanced therapy) after PE were regressed on demographics, RV/LV ratios, traditional ECG signs of RV dysfunction, and SVG components using a logit model.

RESULTS

ECGs from 317 patients (48% male, age 63.1 ± 16.6 years) with acute PE were analyzed; 36 patients (11.4%) experienced an adverse event. Worse RV hypokinesis, larger RV/LV ratio, and smaller TAPSE were associated with smaller SVG X and Y components, larger SVG Z components, and smaller SVG vector magnitude (p < .001 for all). In multivariable logistic regression, odds of adverse events after PE decreased with increasing SVG magnitude and TAPSE (OR 0.32 and 0.54 per standard deviation increase; p = .03 and p = .004, respectively). Receiver operating characteristic (ROC) analysis showed that, when combined with imaging, replacing traditional ECG criteria with the SVG significantly improved the area under the ROC from 0.70 to 0.77 (p = .01).

CONCLUSION

The SVG is correlated with RV dysfunction and adverse outcomes in acute PE and has a better prognostic value than traditional ECG markers.

A Novel Electrocardiography Model for the Diagnosis of Acute Pulmonary Embolism

Acute pulmonary embolism (acPE) is a severe disease that is often misdiagnosed as it is difficult to detect quickly and accurately. In this study, a novel electrocardiogram (ECG) model was used to estimate the probability of acPE rapidly via analysis of ECG characteristics. A total of 327 patients with acPE who were diagnosed at the Sichuan Provincial People's Hospital (SPPH) between 2018 and 2021 were retrospectively studied. A total of 331 patients were randomly selected as the control group, which included patients hospitalized during the same time period. The control group included patients who presented with characteristic symptoms of acPE, but this diagnosis was ruled out following further diagnostic testing. This study compared the diagnostic value of the ECG model with those of another ECG scoring model (Daniel-ECG score) and the most common prediction models (Wells score and Geneva score). This study established an ECG-predictive model using analysis of the ECG abnormalities in patients with acPE. The final ECG model included certain novel ECG signs that had not been incorporated in the previous ECG score of the patients, and thus, compared to the previous ECG score, exhibited a more favorable area under the receiver operating characteristic curve (AUC) value (0.8741). The model developed in this study was named the SPPH-ECG model. Furthermore, this study compared the SPPH-ECG model with Daniel-ECG score, Wells score, and Geneva score, and the SPPH-ECG model was demonstrated to exhibit a superior AUC value (0.8741), sensitivity (79.08%), negative predictive value (79.52%), and test accuracy (79.42%), while the Geneva score presented superior specificity (100%) and positive predictive value (100%) compared with the SPPH-ECG model. In conclusion, the SPPH-ECG model may play a role in ruling out acPE in patients during diagnostic testing and diagnose acPE rapidly and accurately in combination with the Geneva scoring system.

Diagnostic comparison of anterior leads T-wave inversion and McGinn-White sign in suspected acute pulmonary embolism: A systematic review and meta-analysis

Introduction:

Acute pulmonary embolism is the leading cause of cardiovascular mortality in which only 7% of total suspected cases were correctly diagnosed. Prompt diagnosis is essential to reduce disease burden. 12-lead electrocardiography has become standard of examination in any acute cardiovascular setting. Several abnormalities associated with right ventricular dysfunction include the classic McGinn-White and anterior leads T-wave inversion pattern due to conduction abnormalities. Nevertheless, studies conducting research in evaluating diagnostic values of both patterns have not come to definite conclusion. This review evaluates the diagnostic value of T-wave inversions in anterior leads difference compared to that of McGinn-White sign in patients with suspected acute pulmonary embolism.

Methods:

Literature searching was conducted from medical databases. Inclusion-exclusion criteria and study eligibility were assessed to select the included studies in this systematic review. Three final articles were selected and critically appraised using the Oxford Center of Evidence-Based Medicine appraisal tools for diagnostic study.

Results:

Considering the compared importance of selected studies, T-wave inversion shows better specificity (90.9% vs 88.7%) and sensitivity (35.5% vs 28.9%) although both signs exhibit minor impact in terms of sensitivity index. Analyses suggest higher averaged accuracy (accuracy index) and Youden index found in T-wave inversion than that of McGinn-White sign (accuracy index: 57.97% vs 56.16%; Youden index: 0.16 vs 0.12), providing more meaningful diagnostic value. Furthermore, anterior leads T-wave inversion possesses better diagnostic odds ratio than that of McGinn-White sign (5.52 vs 3.17).

Conclusion:

Anterior lead T-wave inversions present better diagnostic value than that of classic pattern of McGinn-White sign in electrocardiographic presentation of suspected acute pulmonary embolism.

Association of the positive T wave in lead aVR with short-term mortality in patients with acute pulmonary embolism

Background: Lead aVR provides prognostic information in various settings for patients with cardiovascular diseases. The present study aimed to investigate the prognostic value of a positive T wave in lead aVR (TaVR) for patients with acute pulmonary embolism (APE).Methods: We screened a total of 412 consecutive patients who were hospitalised with a diagnosis of APE between 2008 and 2018. We investigated electrocardiograms (ECGs) for the presence of a positive TaVR and classified other abnormal ECG findings. Additionally, clinical data, such as echocardiographic findings were recorded, and pulmonary embolism severity index (PESI) scores were calculated. The predictors of mortality at 30 days were investigated as the clinical outcome by logistic regression analysis.Results: In our study population, 54 patients (13.1%) died within 30 days. The prevalence of female gender, congestive heart failure, chronic obstructive pulmonary disease, and mean PESI scores were significantly higher in patients with a positive TaVR compared to those without it. Systolic blood pressure of patients with positive TaVR was significantly lower than that of patients without positive TaVR. In multivariate regression analysis; PESI scores (OR: 1.03; 95% CI: 1.01-1.04, p < .01), Right ventricular end-diastolic diameter (RVEDD) (OR: 1.07 95% CI: 1.01-1.13, p = .02), and a positive TaVR (OR: 4.41; 95% CI: 1.63-11.96, p < .01) were independently correlated with mortality.Conclusion: Positive TaVR, PESI scores, and RVEDD at hospital admission may have prognostic value in patients with APE. Positive T wave in lead aVR could be a useful marker in early risk stratification of pulmonary embolism.

Lack of diagnostic utility of the ECG-derived ventricular gradient in patients with suspected acute pulmonary embolism

INTRODUCTION

The YEARS algorithm was successfully developed to reduce the number of computed tomography pulmonary angiography (CTPA) investigations in the diagnostic management of patients with suspected pulmonary embolism (PE), although half of patients still needed to be referred for CTPA. We hypothesized that ECG derived ventricular gradient optimized for right ventricular pressure overload (VG-RVPO), an easy to use tool for detecting PE-induced pulmonary hypertension (PH), may further improve the efficiency of the YEARS algorithm.

METHODS

In this post-hoc analysis of the Years study, ECGs of 479 patients with suspected PE managed according to the YEARS algorithm were available for analysis. The diagnostic performance of VG-RVPO was assessed and likelihood ratios were calculated.

RESULTS

PE was diagnosed in 88 patients (18%). In patients with confirmed PE, 34% had an abnormal VG-RVPO versus 24% of those without PE (odds ratio 1.6; 95%CI 0.94-2.6). The mean VG-RVPO was -22 ± 13 and did not differ between the two patient groups (-22 versus -20; mean difference - 2, 95% CI -4.8 to 1.3). The sensitivity of VG-RVPO for PE was 24% (95%CI 34-45), the specificity 76% (95%CI 71-80) and the c-statistic 0.45 (95% CI 0.38-0.51). When combined with the YEARS algorithm, the likelihood ratios of VG-RVPO remained close to 1.0. Ruling out PE in patients with an indication for CTPA based on a normal VG-RVPO would have resulted in 58 missed cases.

CONCLUSIONS

The VG-RVPO has no diagnostic value for suspected acute PE, either as stand-alone diagnostic test or combined with the YEARS algorithm.

CONDENSED ABSTRACT

This post-hoc analysis of the YEARS study failed to demonstrate incremental diagnostic value of VG-RVPO for acute PE, either as stand-alone diagnostic test or combined with the YEARS algorithm. Nevertheless, the role of VG-RVPO recorded on admission could potentially be valuable in the risk stratification of PE during hospitalization, although this remains to be studied.

Electrocardiography changes and their significance during treatment of patients with intermediate-high and high-risk pulmonary embolism

BACKGROUND

Electrocardiography (ECG) signs, typical or acute pulmonary embolism, and their changes can be used for the prediction of clinical and haemodynamic outcomes.

PURPOSE

To study the predictive value of the resolution of admission ECG signs in higher risk pulmonary embolism patients for 30-day survival and for the decrease in right ventricular systolic pressure.

METHODS

We analysed the 12-lead ECGs at admission and daily for the first 5 days after hospitalisation in 110 intermediate-high and high-risk pulmonary embolism patients admitted to the intensive care unit of a single tertiary centre. The predictive value of the resolution of four ECG signs were analysed for 30-day survival and for the changes in right ventricular systolic pressure during hospitalisation: S-wave in the first standard lead, right bundle branch block pattern, S-wave in the aVL lead and negative T-waves in precordial leads.

RESULTS

ECG recordings showed the existence of S-wave in the I lead in 71 (64.5%), S-wave in the aVL in 77 (70%), right bundle branch block pattern in 30 (27.3%) and negative T-waves in 66 (60%) patients. All-cause 30-day in-hospital mortality was 13.6%. Among the ECG signs, only the presence of right bundle branch block at admission was significantly associated with 30-day all-cause mortality (hazard ratio (HR) adjusted for age, gender and right ventricular systolic pressure at admission was 7.7, 95% confidence interval (CI) 2.1-27.9; P=0.002). The resolution of three ECG signs during the first 5 days of hospitalisation, S-wave in the I lead (HR 26.4, 95% CI 3.1-226.6; P=0.003), S-wave in the aVL (HR 21.5, 95% CI 2.6-175.3; P=0.004) and right bundle branch block configuration (HR 5.2, 95% CI 1.3-20.8; P=0.020) were associated with 30-day survival. The intermediate-high and high-risk pulmonary embolism patients with S-wave resolution in lead aVL had 0.0% and 7.1% 30-day all-cause mortality, respectively. The patients with resolution of the S-wave in the first lead and in aVL as well as right bundle branch block had more pronounced changes in right ventricular systolic pressure at discharge (27±13 vs. 13±15 mmHg; P=0.011 for S-wave in I lead resolution, 27±12 vs. 15±17 mmHg; P=0.004 for S-wave in aVL resolution and 23±14 vs. 9±14 mmHg; P=0.040 for right bundle branch block resolution) than patients without resolution.

CONCLUSION

Resolution of S-waves and right bundle branch block in ECG correlates with lower all-cause 30-day mortality in intermediate-high and high-risk pulmonary embolism patients. Resolution of S-waves in the first lead and in aVL and right bundle branch block correlates with a decrease of right ventricular systolic pressure.

Prognostic Value of ECG in Patients with Pulmonary Embolism

Aim. To study the significance of electrocardiography (ECG) signs for determining the hospital prognosis in patients with pulmonary embolism (PE).

Material and methods. 472 consecutive patients (49.6% men; average age 58.06±14.28 years) with PE, hospitalized to our center from 23.04.2003 to 18.09.2014 were enrolled into the study. In all cases PE was confirmed by computed tomographic pulmonary angiography and rarely by pulmonary angiography, or by pathology. Patients management was in accordance with appropriate European guidelines. Data of patients' history, clinical symptoms, biochemical markers and instrumental methods (ECG, echocardiography) were analyzed by one-dimensional logistic regression. The end points were: death, shock and hypotension, right ventricular dysfunction and pulmonary hypertension, positive cardiac biomarkers.

pulmonary embolism, electrocardiography, prognosis, collapse, hypotension, dysfunction of the right ventricle. 443 patients (93.9%) without fatal outcome were the first group and 29 patients (6.1%) with a fatal outcome – the second group. SIQIII pattern (33 vs 55.2%; p=0.015), non-complete right bundle branch block (RBBB) (16.3 vs 37.9%; p=0.001), ST segment elevation in lead III (9.7 vs 20.7%, p=0.034), atrial fibrillation (12.9 vs 37.9%, p=0.048) were observed more frequently among patients of group 2. Multivariate analysis revealed that SIQIII pattern (odds ratio [OR] 2.26; 95% confidence interval [95%CI] 1.046-4.868; p=0.038) and RBBB (OR 2.84; 95%CI 1.272-6.327; p=0.011) were associated with worse prognosis. The SIQIII pattern was significantly associated with a fatal outcome with a sensitivity of 55% and a specificity of 33% (AUC=0.611) according to ROC-analysis. Risk of hypotension was related to the following ECG-signs: the p-pulmonale (OR 1.76; 95%CI 1.001-3.088; p=0.049), negative T-wave in lead III (OR 1.8; 95%CI 1.035-3.144; p=0.037). Inversion of the T wave in lead III was associated with the development of shock (OR 1.98; 95%CI 0.891-4.430; p=0.043).

ECG-signs were also associated with the development of right ventricular dysfunction and pulmonary hypertension: right axis deviation (OR 1.035; 95%CI 1.008-1.062; p=0.01), ST-segment elevation in the AVR lead (OR 3.769; 95%CI 1.018-13.955; p=0.047), negative T wave in leads III, V1-V3 (OR 1.015; 95%CI 1.008-1.023; p=0.001 and OR 1.014; 95%CI 1.005-1.022; p=0.001, respectively), RBBB (OR 1.013; 95%CI 1.003- 1.024; p=0.012), p-pulmonale (OR 1.015; 95%CI 1.007-1.023; p=0.001), deep S in leads V5-V6 (OR 1.015; 95%CI 1.006-1.024; p=0.001). However, there was no significant relationship between ECG signs and cardiac biomarkers (troponin I and BNP).

Conclusions. SIQIII pattern, RBBB and inversion of the T wave in lead III have prognostic value in unselected population of patients with PE. 

ECG in suspected pulmonary embolism

Objective

To establish the diagnostic value of prespecified ECG changes in suspected pulmonary embolism (PE).

Methods

Retrospective case–control study in a district general hospital setting. We identified 189 consecutive patients with suspected PE whose CT pulmonary angiogram (CTPA) was positive for a first PE and for whom an ECG taken at the time of presentation was available. We matched these for age±3 years with 189 controls with suspected PE whose CTPA was negative. We considered those with large (n=76) and small (n=113) clot load separately. We scored each ECG for the presence or absence of eight features that have been reported to occur more commonly in PE.

Results

20%–25% of patients with PE, including those with large clot load, had normal ECGs. The most common ECG abnormality in patients with PE was sinus tachycardia (28%). S1Q3T3 (3.7%), P pulmonale (0.5%) and right axis deviation (4.2%) were infrequent findings. Right bundle branch block (9.0%), atrial dysrhythmias (10.1%) and clockwise rotation (20.1%) occurred more frequently but were also common in controls. Right ventricular (RV) strain pattern was significantly more commonly in patients than controls, 11.1% vs 2.6% (sensitivity 11.1%, specificity 97.4%; OR 4.58, 95% CI 1.63 to 15.91; p=0.002), particularly in those with large clot load, 17.1% vs 2.6% (sensitivity 17.1%, specificity 97.4%; OR 7.55, 95% CI 1.62 to 71.58; p=0.005).

Conclusion

An ECG showing RV strain in a breathless patient is highly suggestive of PE. Many of the other ECG changes that have been described in PE occur too infrequently to be of predictive value.

Characteristics of synthesized right-sided chest electrocardiograms in patients with acute pulmonary embolism

BACKGROUND

The significance of right-sided chest lead electrocardiogram (ECG) abnormalities in acute pulmonary embolism (APE) is unclear. This study evaluated the characteristics of such abnormalities in APE patients.

METHODS

This retrospective study included consecutive patients who were diagnosed with APE by contrast-enhanced computed tomography or pulmonary artery angiography. A standard 12-lead ECG and a synthesized right-sided chest ECG were obtained from these patients. Waveform differences were noted between the acute and post-treatment phases.

RESULTS

In total, 56 APE patients (18 men and 38 women, mean age 66.7±13.3 years) were included. Traditional ECG findings, such as right-axis deviation, the S₁Q₃T₃ pattern, and clockwise rotation, were found in relatively few patients (14.3%, 32.1%, and 21.4%, respectively). In some cases, a negative T wave in standard 12-lead ECGs was observed in leads III, V1, and V2 (46.4%, 60.7%, and 39.9%, respectively). Syn-V3R ECG showed a higher frequency of negative T waves (66.1%) at the onset and significantly (p<0.01) decreased at the follow-up. Multiple logistic regression analyses for differentiating APE revealed that the negative T waves only in lead syn-V3R were significantly related (odds ratio: 6.95, 95% confidence interval: 2.50-19.32, p<0.001).

CONCLUSIONS

The presence of a negative T wave in a synthesized right-sided chest ECG, particularly in the V3R lead, is a new and distinctive finding denoting pulmonary embolism. To confirm the utility of this characteristic using synthesized right-sided chest ECGs for the diagnosis of APE, further studies with larger populations will be required.

A new criterion to differentiate atrioventricular nodal reentrant tachycardia from atrioventricular reciprocating tachycardia: Combined AVR criterion

AIM

A combined aVR criterion is described as the presence of a pseudo r' wave in aVR during tachycardia in patients without r' wave in aVR in sinus rhythm and/or a ≥50% increase in r' wave amplitude compared to sinus rhythm in patients with r' wave in the basal aVR lead. We aimed to investigate the use of combined aVR criterion in differential diagnosis of atrioventricular nodal reentrant tachycardia (AVNRT) and atrioventricular reciprocating tachycardia (AVRT).

METHODS

In this prospective study, 480 patients with inducible narrow QRS supraventricular tachycardia (SVT) were included. Twelve-lead electrocardiogram (ECG) was conducted during tachycardia and sinus rhythm. The patients were divided into two groups according to the arrhythmia mechanism that determined via EPS, AVNRT, and AVRT. Criteria of narrow QRS complex tachycardia were compared between the two groups.

RESULTS

AVNRT was present in 370 (77%) patients and AVRT in 110 (23%) patients. Combined aVR criterion was found to be more frequent in patients with AVNRT (84.1% and 9.1%, p < 0.001). In logistic regression analysis, combined aVR criterion and classical ECG criterion were found to be the most important predictors of AVNRT (p < 0.001). The sensitivity, specificity, positive predictive value, and negative predictive value of the combined aVR criterion for AVNRT were 84.1%, 90.9%, 96.9%, and 62.9%, respectively.

CONCLUSION

In the differential diagnosis of patients with SVT, the combined aVR criterion identifies the presence of AVNRT with an independent and acceptable diagnostic value. In addition to classical ECG criteria for AVNRT, it is necessary to evaluate the combined aVR criterion in daily practice.

Nonthrombogenic, stretchable, active multielectrode array for electroanatomical mapping

High-precision monitoring of electrophysiological signals with high spatial and temporal resolutions is one of the most important subjects for elucidating physiology functions. Recently, ultraflexible multielectrode arrays (MEAs) have been fabricated to establish conformal contacts with the surface of organs and to measure propagation of electrophysiological signals with high spatial-temporal resolution; however, plastic substrates have high Young's modulus, causing difficulties in creating appropriate stretchability and blood compatibility for applying them on the dynamically moving and surgical bleeding surface of the heart. Here, we have successfully fabricated an active MEA that simultaneously achieves nonthrombogenicity, stretchability, and stability, which allows long-term electrocardiographic (ECG) monitoring of the dynamically moving hearts of rats even with capillary bleeding. Because of the active data readout, the measured ECG signals exhibit a high signal-to-noise ratio of 52 dB. The novel stretchable MEA is carefully designed using state-of-the-art engineering techniques by combining extraordinarily high gain organic electrochemical transistors processed on microgrid substrates and a coating of poly(3-methoxypropyl acrylate), which exhibits significant antithrombotic properties while maintaining excellent ionic conductivity.

Case report and systematic review of pulmonary embolism mimicking ST-elevation myocardial infarction

Background

To study trends in the clinical presentation, electrocardiograms, and diagnostic imaging in patients with pulmonary embolism presenting as ST segment elevation.

Methods

We performed a systematic literature search for all reported cases of pulmonary embolism mimicking ST-elevation myocardial infarction. Pre-specified data such as clinical presentation, electrocardiogram changes, transthoracic echocardiographic findings, cardiac biomarkers, diagnostic imaging, therapy, and outcomes were collected.

Results

We identified a total of 34 case reports. There were 23 males. Mean age of the population was 56.5 ± 15.5 years. Patients presented with dyspnea (76.4%), chest pain (63.6%), and tachycardia (71.4%). All patients presented with ST-elevations, with the most common location being in the anterior-septal distribution, lead V3 (74%), V2 (71%), V1 (62%) and V4 (47%). ST-segment elevations in the inferior distribution were present in lead II (12%), III (18%), and aVF (21%). Presentation was least likely in the lateral distribution. Troponin was elevated in 78.9% of cases. Right ventricular strain was the most common echocardiographic finding. Over 80% of patients had findings consistent with elevated right ventricular pressure, with 50% reported RV dilatation and 20% RV hypokinesis. The most commonly used imaging modality was contrast-enhanced pulmonary angiography. There was a greater incidence of bilateral compared to unilateral pulmonary emboli (72.4% vs. 10%). About 65% patients received anticoagulation and 36.3% were treated with thrombolytics. Forty-six percent of patients required intensive care and 18.7% intubation. Overall mortality was 25.8%.

Conclusions

A review of the literature reveals that in patients presenting with pulmonary embolism, electrocardiogram findings of ST-segment elevations will occur predominantly in the anterior-septal distribution.

New Electrocardiographic Changes in Patients Diagnosed with Pulmonary Embolism

BACKGROUND

The electronic medical record is a relatively new technology that allows quick review of patients' previous medical records, including previous electrocardiograms (ECGs). Previous studies have evaluated ECG patterns predictive of pulmonary embolism (PE) at the time of PE diagnosis, though none have examined ECG changes in these patients when compared with their previous ECGs.

OBJECTIVE

Our aim was to identify the most common ECG changes in patients with known PE when their ECGs were compared with their previous ECGs.

METHODS

A retrospective chart review of patients diagnosed with PE in the emergency department was performed. Each patient's presenting ECG was compared with their most recent ECG obtained before diagnosis of PE.

RESULTS

A total of 352 cases were reviewed. New T wave inversions, commonly in the inferior leads, were the most common change found, occurring in 34.4% of cases. New T wave flattening, also most commonly in the inferior leads, was the second most common change, occurring in 29.5%. A new sinus tachycardia occurred in 27.3% of cases. In 24.1% of patients, no new ECG changes were noted, with this finding more likely to occur in patients younger than 60 years.

CONCLUSIONS

The most common ECG changes when compared with previous ECG in the setting of PE are T wave inversion and flattening, most commonly in the inferior leads, and occurring in approximately one-third of cases. Approximately one-quarter of patients will have a new sinus tachycardia, and approximately one-quarter will have no change in their ECG.

Right bundle branch block and SIQIII-type patterns for risk stratification in acute pulmonary embolism

INTRODUCTION

Risk stratification in acute pulmonary embolism (PE) is crucial for identification of patients with poor prognosis. We aimed to investigate the ECG alterations of right bundle branch block (RBBB) and SIQIII-type patterns for risk stratification in acute PE.

MATERIALS AND METHODS

Retrospective analysis of PE patients, treated in the Internal Medicine Department, was performed. Patients with RBBB and/or SIQIII-type were compared with those without both patterns. Logistic regression models for association between these ECG alterations and respectively right ventricular dysfunction (RVD), high-risk PE status and myocardial injury were computed.

RESULTS

175 patients were included for this retrospective analysis. Total study sample comprised 37 PE patients (21.1%) with RBBB and/or SIQIII-type patterns and 138 PE patients (78.9%) without both signs. Heart rate (97.4±17.2 vs. 93.2±26.8/min, P=0.021), cardiac troponin I values (0.19±0.38 vs. 0.11±0.24, P=0.003) and percentage of patients with RVD (83.9% vs. 52.7%, P=0.005) were significantly higher in PE patients with RBBB and/or SIQIII-type patterns compared to PE patients without both ECG alterations. Multi-variate logistic regression models adjusted for age and gender revealed significant associations between RBBB and RVD (OR3.942, 95% CI1.054-14.747, P=0.042) and between SIQIII-type patterns and RVD (OR5.667, 95% CI1.144-28.071, P=0.034). The association between RBBB and cardiac injury (cTnI>0.4ng/ml) (OR2.531, 95% CI 0.973-6.583, P=0.06) showed a borderline significance, while the association between SIQIII-type patterns and cardiac injury was significant (OR3.956, 95% CI1.309-11.947, P=0.015).

CONCLUSIONS

RBBB and SIQIII-type patterns were both associated with RV overload and cardiac injury. RBBB and SIQIII-type patterns were connected with 3.9-fold and 5.7-fold elevated risk of RVD, respectively.

The value of electrocardiographic abnormalities in the prognosis of pulmonary embolism: a consensus paper

Electrocardiographic (ECG) abnormalities in the setting of acute pulmonary embolism (PE) are being increasingly characterized and mounting evidence suggests that ECG plays a valuable role in prognostication for PE. We review the historical 21-point ECG prognostic score for the severity of PE and examine the updated evidence surrounding the utility of ECG abnormalities in prognostication for severity of acute PE. We performed a literature search of MEDLINE, EMBASE, and PubMed up to February 2015. Article titles and abstracts were screened, and articles were included if they were observational studies that used a surface 12-lead ECG as the instrument for measurement, a diagnosis of PE was confirmed by imaging, arteriography or autopsy, and analysis of prognostic outcomes was performed. Thirty-six articles met our inclusion criteria. We review the prognostic value of ECG abnormalities included in the 21-point ECG score, including new evidence that has arisen since the time of its publication. We also discuss the potential prognostic value of several ECG abnormalities with newly identified prognostic value in the setting of acute PE.

Fragmented QRS Complex Predicts In-Hospital Adverse Events and Long-Term Mortality in Patients with Acute Pulmonary Embolism

BACKGROUND

Electrocardiographic (ECG) abnormalities in pulmonary embolism (PE) are increasingly reported, and mounting data have recommended that ECG plays a crucial role in the prognostic assessment of PE patient population. However, there is scarce data on the prognostic importance of fragmented QRS (fQRS) on short- and long-term outcomes in patients with PE. Therefore, we aimed to investigate the prognostic role of fQRS in predicting in-hospital and long-term adverse outcomes in PE patients.

METHODS

A total of 249 patients (155 female, 66.2%; mean age, 66.0 ± 16.0) with the diagnosis of acute PE were enrolled and followed-up during median 24.8 months.

RESULTS

Compared with the fQRS (-) patient group, patients with fQRS showed higher rates of in-hospital adverse events including cardiogenic shock, the necessity of thrombolytic therapy, and in-hospital mortality as well as long-term all-cause mortality. In Kaplan-Meier survival analysis, during follow-up, all-cause mortality occurred more frequently in the fQRS (+) group (log-rank, P = 0.002). In multivariate Cox regression analysis, adjusted with other relevant parameters, the presence of fQRS were determined as an independent predictor of in-hospital adverse events (HR: 2.743, 95% CI: 1.267-5.937, P = 0.003) and long-term all-cause mortality (HR: 3.137, 95% CI: 1.824-6.840, P = 0.001).

CONCLUSIONS

The presence of fQRS complex, as a simple and feasible ECG marker, seems to be a novel predictor of in-hospital adverse events and long-term all-cause mortality in PE patient population. This parameter may utilize the identification of patients whom at higher risk for mortality and individualization of therapy.

ST-segment elevation in V1-V4 in acute pulmonary embolism: a case presentation and review of literature

INTRODUCTION

Electrocardiographic (ECG) abnormalities are seen in 70%-80% of patients with acute pulmonary embolism (APE). Rarely, APE presents with ST-segment elevation (STE) in leads V1-V4, mimicking ST-segment elevation myocardial infarction (STEMI). Herein, we describe a case of APE presenting with STE in V1-V3, along with a comprehensive review of the literature.

METHODS

We reviewed Pubmed/Medline indexed articles from 1950 to 2014 reporting cases of APE presenting with STE in V1-V3 or V4 (V1-V3/V4). Cases were analyzed with specific reference to patient demographics, clinical, laboratory, and radiological data, treatment, and outcome.

RESULTS

A total of 12 cases were identified comprising seven males and five females aged between 31 and 64 years. Five cases met the American College of Cardiology/American Heart Association criteria for massive APE due to sustained hemodynamic instability or requirement for inotropic support, and seven met criteria for submassive PE due to right ventricular (RV) dysfunction or elevated troponin in absence of systemic hypotension. Among the notable clinical features in this cohort is the high incidence of syncope, in 66.7% of the cases, high incidence of concomitant deep venous thrombosis (DVT) in 90% of cases that reported venous Doppler results (eight proximal and one distal DVT), and the presence of a dilated RV in 90% of the cases that reported echocardiographic results. In all but one case the initial working diagnosis was STEMI and emergent cardiac catheterization was planned. In the 90% of cases who eventually had a coronary angiography, the angiogram was performed prior to diagnosing APE, and the lack of occlusive disease prompted further workup that confirmed the diagnosis of APE. In-hospital mortality rate in the studied population was 16.7%.

CONCLUSION

STE in leads V1-V3/V4 in cases with APE identifies a subset of patients who are an intermediate to high risk category. In cases presenting with right precordial lead STE and clinical features that are more suggestive of APE rather than STEMI, a computed tomography pulmonary angiogram is warranted for earlier diagnosis of suspected APE, which allow for immediate-rather than delayed-initiation of therapeutic anticoagulant therapy if the diagnosis is confirmed and may avert the need for coronary angiography.

Submassive pulmonary embolism

Pulmonary embolism (PE) is a common diagnosis in critical care. Depending on the severity of clot burden, the clinical picture ranges from nearly asymptomatic to cardiovascular collapse. The signs and symptoms of PE are nonspecific. The clinician must have a high index of suspicion to make the diagnosis. PE is risk stratified into 3 categories: low-risk, submassive, and massive. Submassive PE remains the most challenging with regard to initial and long-term management. Little consensus exists as to the appropriate tests for risk stratification and therapy. This article reviews the current literature and a suggested approach to these patients.

T-wave inversion in patients with acute pulmonary embolism: prognostic value

INTRODUCTION

T-wave inversion (TWI) is a common ECG finding in patients with acute pulmonary embolism (APE).

OBJECTIVES

To determine the prevalence of TWI in patients with APE and to describe their relationship to outcomes.

METHODS

Retrospective study of 437 patients with APE. TWI patterns were described in two distributions: inferior (II, III, aVF) and precordial (V1-V6).

RESULTS

TWI was observed in 258 (59%) patients. The mortality rate was significantly higher in the group with TWI in the inferior AND precordial leads compared to the group without TWI (OR: 2.74; p = 0.024) and the group with TWI in the inferior OR precordial leads (OR: 2.43; p = 0.035). As compared those with TWI in <5 leads, patients with TWI in ≥5 leads experienced significantly higher rates of death (17.1% vs. 6.6%, OR: 2.92; p = 0.002) and complications.

CONCLUSIONS

TWI and the quantitative assessment thereof can be useful to risk stratify patients with APE.

Use of ischemic ECG patterns for risk stratification in intermediate-risk patients with acute PE

BACKGROUND

European recommendations on the management of acute pulmonary embolism (APE) divide patients into 3 risk categories: high, intermediate, and low. Mortality has previously been estimated at 3% to 15% in the intermediate group. The aim of this study was to use a new metric "ischemic electrocardiographic (ECG) patterns" to more precisely estimate the risk (complications or death) of APE patients identified as "intermediate risk" by current European Society of Cardiology (ESC) criteria.

METHODS

The study group consisted of 500 consecutive patients (290 females), with a mean age 66.3 ± 15.2 years, and 245 (72.8%) patients were initially classified as intermediate risk. Four ischemic ECG patterns were studied: (i) ST-segment ischemic pattern (STIP), (ii) global ischemic pattern (GIP), (iii) negative T wave pattern, and (iv) control group consisting of patients with no ischemic changes.

RESULTS

Predictors of death in univariate analysis included elevated troponin concentration (odds ratio [OR], 6.8; 95% confidence interval [CI], 1.28-169; P = 0.02]) and ischemic ECG patterns: STIP (OR, 6.3; 95% CI, 1.6-46.0; P = 0.007). Patients with right ventricular dysfunction (RVD) who were STIP (+) experienced significantly higher mortality rate compared to RVD patients who were STIP(-) (11.4% vs 1.6%; OR, 7.26; 95% CI, 1.82-52.8; P = 0.004). In patients with STIP (+) as compared to STIP (-), rate of death (OR, 6.35; P = 0.007) and rate of complications (OR, 4.19; P = 0.002) were significantly higher. Neither presence of negative T-waves nor GIP pattern was associated with a worse prognosis.

CONCLUSIONS

In patients with APE, an ischemic ECG pattern on hospital admission, when identified in addition to classic risk markers, is an independent risk factor for worse in-hospital outcomes.

Bedside cardiac testing in acute cor pulmonale

We present a case where an ECG and echocardiogram suggested pulmonary embolism and early treatment led to a positive outcome.

New onset S wave in pulmonary embolism: revisited (something old and something new)

We report a case of a young man who had a new onset S wave in lead 1 in his ECG with typical symptoms of acute onset of dyspoena 2 months after an episode of deep vein thrombosis, S wave disappeared 6 days after thrombolysis. We report this case as the clinical course was very typical plus we have reviewed the literature regarding diagnosis and risk stratification of pulmonary embolism for the student, or the casualty medical officer.

Correlation between ST-segment elevation and negative T waves in the precordial leads in acute pulmonary embolism: insights into serial electrocardiogram changes

BACKGROUND

Acute pulmonary embolism (APE) is often misdiagnosed as acute coronary syndrome because of the similarity of the presenting symptoms and of the electrocardiogram (ECG) manifestations. In APE, ST-segment elevation (STE) in leads V1 to V3 /V4 , mimicking anteroseptal myocardial infarction, is not a rare phenomenon. Negative T waves (NTW) in the precordial leads mimicking the "Wellens' syndrome" is an important ECG manifestation of APE. The evolution of these ECG changes-STE and NTW-in APE has not been thoroughly studied.

METHODS

We present two patient cases with APE and their evolving serial ECGs to analyze the correlation between STE and NTW.

RESULTS

NTW developed later than STE in these two patient cases.

CONCLUSIONS

NTW might represent a "postischemic" ECG pattern indicating a previous stage with transmural myocardial ischemia.

Therapeutic hypothermia-induced electrocardiographic changes and relations to in-hospital mortality

BACKGROUND

Therapeutic hypothermia improves survival for selected patients who remain comatose after cardiac arrest. Hypothermia triggers changes in electrocardiographic (ECG) parameters; however, the association of these changes to in-hospital mortality remains unclear.

HYPOTHESIS

QT interval changes induced by therapeutic hypothermia are not associated with in-hospital mortality.

METHODS

We retrospectively compared precooling ECG parameters to ECG parameters during hypothermia on all consecutive patients with available information who received hypothermia at our academic medical center between December 2006 and July 2012 (N = 101; 24% women). Paired 2-sample t test was used to compare precooling vs cooling ECG parameters. In-hospital mortality related to ECG parameter changes was compared using the Pearson χ(2) test.

RESULTS

Therapeutic hypothermia resulted in increases in PR and QTc intervals and decreases in heart rate and QRS intervals (P for all <0.02). During hospitalization, 45 of the 101 patients died. Survivors vs nonsurvivors did not differ in heart rate change (P = 0.74), PR change (P = 0.57), QRS change (P = 0.09), or QTc change (P = 0.67). Comparing patients who had reduced QTc intervals with hypothermia to those who had prolonged QTc with hypothermia, 14 out of 30 died in the former group, whereas 31 out of 71 died in the latter group (46.7% vs 43.7%, odds ratio [OR]: 1.13, 95% CI: 0.48-2.66). Patients presenting with right bundle branch block (RBBB) had a higher risk of in-hospital death compared to those without RBBB (72.2% vs 38.6%, OR: 4.14, 95% CI: 1.35-12.73).

CONCLUSIONS

Therapeutic hypothermia prolonged QTc interval with no association to in-hospital mortality. Presence of RBBB on initial presentation was related to increased mortality.

Variable ECG findings associated with pulmonary embolism

An elderly man with a recent diagnosis of invasive rectal adenocarcinoma was admitted to the hospital because of a lower gastrointestinal bleeding and low haemoglobin. During the hospitalisation he complained of chest pain. ECG showed new onset ST-segment elevation in leads III, aVF and in the precordial leads V1-V4. Shortly thereafter, he became hypotensive and coded. Despite resuscitation he passed away. Autopsy revealed massive pulmonary emboli with near complete obstruction of the involved branches of the pulmonary arteries. Coronary arteries were free of significant coronary artery disease and multiple sections of the myocardium showed the absence of myocardial infarction.

An unusual presentation of pulmonary embolism

Pulmonary embolism (PE) is a common cardiovascular emergency, by which occlusion of a part of the pulmonary arterial bed may lead to acute life threatening but potentially reversible right ventricular failure. Early diagnosis is fundamental to implement immediate effective treatment to reduce mortality. However, the diagnosis can be easily missed due to non-specific clinical presentation. We wish to present an unusual case whereby a patient with no risk factors for PE, symptoms suggestive of acute pericarditis and an ECG showing concave ST segment elevation was found to have multiple pulmonary emboli.

Care of patients with acute pulmonary emboli: a clinical review with cardiovascular focus

Acute pulmonary embolism (PE) is a common, multidisciplinary disease with substantial associated morbidity, mortality and healthcare expense. In this article we present a succinct review of diagnostic tools, risk stratification and medical therapies for cardiovascular care of patients with acute PE. While pulmonary angiography remains the 'gold standard' for diagnosis, a host of diagnostic modalities, interpreted in the setting of clinical probability, are available for patient assessment, including ECG, chest radiography, D-dimer, lower-extremity venous ultrasound, ventilation-perfusion scans, computed tomography and magnetic resonance angiography, and echocardiography, each with associated value. Diagnostic algorithms incorporate multiple tools in order to obtain a more comprehensive evaluation. Therapeutic anticoagulation remains the mainstay of therapy in PE. In massive PE, utilization of thrombolysis is reasonable in the absence of contraindications. Submassive PE, characterized by right ventricular dysfunction as assessed by echocardiography and ECG, is associated with higher mortality. Use of thrombolysis in submassive PE remains controversial. Catheter-directed therapies are emerging as an added approach to acute PE and have the potential to improve outcomes in PE. Use of inferior vena cava filters should be pursued in a select patient population as they serve to reduce recurrent acute PE; however, they are associated with more frequent deep venous thrombosis and provide no mortality benefit. In risk-stratified hemodynamically stable patients, an outpatient management strategy inclusive of therapeutic anticoagulation and careful clinical follow-up may be appropriate.

The role of ST-segment elevation in lead aVR in the risk assessment of patients with acute pulmonary embolism

BACKGROUD AND AIM: Patients with acute pulmonary embolism (APE) present with highly variable symptoms and ECG abnormalities. As ST-elevation in lead aVR has recently been described to predict right ventricular dysfunction (RVD), we aimed to correlate this sign to the severity of APE.

METHODS

Three-hundred ninety-six consecutive patients (in centers a and b) with proven APE were retrospectively analysed with respect to 12-lead-ECG, symptoms, thrombus location, echocardiograpy, troponin T, initial therapy and outcome. Data were then compared between patients with and without aVR-ST-elevation.

RESULTS

On admission aVR-ST-elevation was present in 34.3% (n = 136). Presence of aVR-ST-elevation was assossiated with more severe clinical presentation (dyspnoea at rest 44.9 vs. 29.2%; p = 0.002, hypotension 17.0 vs. 6.5%; p = 0.001, syncope 16.2 vs. 6.5%; p = 0.002), higher median troponin T levels (0.035 [0.01-0.2] versus 0.01 [0.01-0.02]; p < 0.001), more frequent RVD (74.5 vs. 46.6%; p < 0.001) and central located thrombi (50.8 vs. 29.2; p < 0.001). Thrombolysis was used more frequently (29.1 vs. 7.5%; p < 0.001) and in-hospital-mortality was increased (10.3 vs. 5.4%; p = 0.07) when compared to patients without that sign. Mortality in intermediate-risk APE patients with aVR-ST-elevation was 8.9% compared to 0% in those without (p = 0.04). In contrast, the presence of other classical ECG pattern of APE did not further increase mortality in intermediate-risk patients.

CONCLUSIONS

ST-elevation in lead aVR is associated with a more severe course of APE, especially in patients with intermediate-risk. Therefore, aVR-ST-elevation might be useful in risk stratification of APE.

The presence of ST-elevation in lead aVR predicts significant left main coronary artery stenosis in cardiogenic shock resulting from myocardial infarction: the Manitoba cardiogenic shock registry

INTRODUCTION

Electrocardiographic (ECG) predictors of significant angiographic left main coronary artery stenosis (LMCS>50%) have been described in acute myocardial infarction using ST-segment elevation in lead aVR (aVR-STE). However, there is a paucity of data on its association with LMCS>50% in the setting of cardiogemic shock (CGS).

METHODS

We investigated 210 consecutive, unselected, patients from Sept. 2002-2006 with CGS due to acute myocardial infarction undergoing cardiac catheterization. Of those, 191 patients with interpretable ECG tracings for aVR-STE analysis formed our study sample. aVR-STE was defined as ST-segment elevation≥1mm in aVR while LMCS>50% on coronary angiogram was defined as any left main lesion that demonstrated >50% lumen narrowing or equivalent by direct visualization or quantitative coronary angiography analysis.

RESULTS

There was 59% survival to discharge of this predominantly male cohort (median age 68±12years; 31% females). Fifty three (28%) cases had aVR-STE while 27 (14%) had LMCS>50%. Of those, 16 patients who had aVR-STE also had LMCS>50% (sensitivity 59%, specificity 77%, positive predictive value 30%, negative predictive value 92% for predicting LMCS>50%). Multivariate analysis revealed that aVR-STE was the only significant predictor of LMCS>50% was (p=0.014; Odds Ratio=3.06; 95% Confidence Interval 1.26-7.47).

CONCLUSION

In CGS due to acute myocardial infarction, aVR-STE>1mm proves to be an important predictor of LMCS>50%. Such data could be helpful in further risk stratification for optimal management during CGS.

Diagnosis and management of life-threatening pulmonary embolism

Pulmonary embolus (PE) is estimated to cause 200 000 to 300 000 deaths annually. Many deaths occur in hemodynamically unstable patients and the estimated mortality for inpatients with hemodynamic instability is between 15% and 25%. The diagnosis of PE in the critically ill is often challenging because the presentation is nonspecific. Computed tomographic pulmonary angiography appears to be the most useful study for diagnosis of PE in the critically ill. For patients with renal insufficiency and contrast allergy, the ventilation perfusion scan provides an alternative. For patients too unstable to travel, echocardiography (especially transesophageal echocardiography) is another option. A positive result on lower extremity Doppler ultrasound can also aid in the decision to treat. The choice of treatment in PE depends on the estimated risk of poor outcome. The presence of hypotension is the most significant predictor of poor outcome and defines those with massive PE. Normotensive patients with evidence of right ventricular (RV) dysfunction, as assessed by echocardiography, comprise the sub-massive category and are at intermediate risk of poor outcomes. Clinically, those with sub-massive PE are difficult to distinguish from those with low-risk PE. Cardiac troponin, brain natriuretic peptide, and computed tomographic pulmonary angiography can raise the suspicion that a patient has sub-massive PE, but the echocardiogram remains the primary means of identifying RV dysfunction. The initial therapy for patients with PE is anticoagulation. Use of vasopressors, inotropes, pulmonary artery (PA) vasodilators and mechanical ventilation can stabilize critically ill patients. The recommended definitive treatment for patients with massive PE is thrombolysis (in addition to anticoagulation). In massive PE, thrombolytics reduce the risk of recurrent PE, cause rapid improvement in hemodynamics, and probably reduce mortality compared with anticoagulation alone. For patients with a contraindication to anticoagulation and thrombolytic therapy, surgical embolectomy and catheter-based therapies are options. Thrombolytic therapy in sub-massive PE results in improved pulmonary perfusion, reduced PA pressures, and a less complicated hospital course. No survival benefit has been documented, however. If one is considering the use of thrombolytic therapy in sub-massive PE, the limited documented benefit must be weighed against the increased risk of life-threatening hemorrhage. The role of surgical embolectomy and catheter-based therapies in this population is unclear. Evidence suggests that sub-massive PE is a heterogeneous group with respect to risk. It is possible that those at highest risk may benefit from thrombolysis, but existing studies do not identify subgroups within the sub-massive category. The role of inferior vena cava (IVC) filters, catheter-based interventions, and surgical embolectomy in life-threatening PE has yet to be completely defined.

The T wave inversion score is useful for evaluating the time-course of acute pulmonary embolism

BACKGROUND

The 12-lead electrocardiogram (ECG) has relatively poor specificity for identifying acute pulmonary embolism (APE). The aim of this study was to investigate ECG abnormalities according to 2 different criteria and their usefulness for assessing changes in APE.

METHODS AND RESULTS

Fifty-two APE patients underwent ECG examinations in the acute and chronic phases. ECG abnormalities were assessed according to Stein's criteria (QRS complex abnormalities and T wave inversion in any lead except aV(L), III, aV(R), or V₁) and Kosuge's criteria (T wave inversion in any lead except aV(R) or aV(L)). Many patients had electrocardiographic abnormalities in the acute phase, but no specific abnormalities were found. According to Kosuge's criteria, the frequency of T wave inversion was higher than that of abnormal QRS complexes and T wave inversion according to Stein's criteria (P < 0.01). In 20 cases with preclinical ECG records, the time-course of changes in the T wave inversion score (total numbers of T wave inversions per patient) was examined. The peak T wave inversion score was noted at 3 days after onset (P < 0.01).

CONCLUSIONS

These results suggest that the T wave inversion score, calculated according to Kosuge's criteria, is useful for predicting the time-course of APE.

Pulmonary embolism presenting with evolving electrocardiographic abnormalities mimicking anteroseptal myocardial infarction: a case report

OBJECTIVES

To report a case with dynamic ST segment elevation suggestive of anteroseptal acute myocardial infarction (AMI) that proved to be bilateral pulmonary thromboembolism (PTE).

CLINICAL PRESENTATION AND INTERVENTION

A 50-year-old woman with syncope was transferred to the emergency department. Findings from the admission electrocardiogram were suggestive of anteroseptal AMI; however, coronary angiography revealed that the patient had normal coronary arteries. On further evaluation, the patient was found to have massive bilateral PTE.

CONCLUSION

This report emphasizes the role of evolving electrocardiographic changes in the diagnosis of PTE, particularly in patients with chest pain and ST segment elevation suggestive of acute coronary syndrome.

Electrocardiography patterns and the role of the electrocardiography score for risk stratification in acute pulmonary embolism

Background and Objectives

Data on the usefulness of a combination of different electrocardiography (ECG) abnormalities in risk stratification of patients with acute pulmonary embolism (PE) are limited. We thus investigated 12-lead ECG patterns in acute PE to evaluate the role of the ECG score in risk stratification of patients with acute PE.

Subjects and Methods

One hundred twenty-five consecutive patients (63±14 years, 56 men) with acute PE who were admitted to Kyungpook National University Hospital between November 2001 and January 2008 were included. We analyzed ECG patterns and calculated the ECG score in all patients. We evaluated right ventricular systolic pressure (RVSP) (n=75) and RV hypokinesia (n=80) using echocardiography for risk stratification of acute PE patients.

Results

Among several ECG findings, sinus tachycardia and inverted T waves in V_1-4 (39%) were observed most frequently. The mean ECG score and RVSP were 7.36±6.32 and 49±21 mmHg, respectively. The ECG score correlated with RVSP (r=0.277, p=0.016). The patients were divided into two groups {high ECG-score group (n=38): ECG score >12 and low ECG-score group (n=87): ECG score ≤12} based on the ECG score, with the maximum area under the curve. RV hypokinesia was observed more frequently in the high ECG-score group than in the low ECG-score group (p=0.006). Multivariate analysis revealed that a high ECG score was an independent predictor of high RVSP and RV hypokinesia.

Conclusion

Sinus tachycardia and inverted T waves in V_1-4 were commonly observed in acute PE. Moreover, the ECG score is a useful tool in risk stratification of patients with acute PE.

Electrocardiographic differentiation between acute pulmonary embolism and non-ST elevation acute coronary syndromes at the bedside

BACKGROUND

Clinical picture of acute pulmonary embolism (APE), with wide range of electrocardiographic (ECG) abnormalities can mimic acute coronary syndromes.

OBJECTIVES

Assessment of standard 12-lead ECG usefulness in differentiation at the bedside between APE and non-ST elevation acute coronary syndrome (NSTE-ACS).

METHODS

Retrospective analysis of 143 patients: 98 consecutive patients (mean age 63.4 +/- 19.4 year, 45 M) with APE and 45 consecutive patients (mean age 72.8 +/- 10.8 year, 44 M) with NSTE-ACS. Standard ECGs recorded on admission were compared in separated groups.

RESULTS

Right bundle branch block (RBBB) and S(1)S(2)S(3) or S(1)Q(3)T(3) pattern were found in similar frequency in both groups (10 [11%] APE patients vs 6 [14%] NSTE-ACS patients, 27 [28%] patients vs 7 [16%] patients, respectively, NS). Negative T waves in leads V(1-3) together with negative T waves in inferior wall leads II, III, aVF (OR 1.3 [1.14-1.68]) significantly indicated APE with a positive predictive value of 85% and specificity of 87%. However, counterclockwise axis rotation (OR 4.57 [2.74-7.61]), ventricular premature beats (OR 2.60 [1.60-4.19]), ST depression in leads V(1-3) (OR 2.25 [1.43-3.56]), and negative T waves in leads V(5-6) (OR 2.08 [1.31-3.29]) significantly predicted NSTE-ACS.

CONCLUSIONS

RBBB, S(1)S(2)S(3), or S(1)Q(3)T(3) pattern described as characteristic for APE were not helpful in the differentiation between APE and NSTE-ACS in studied group. Coexistence of negative T waves in precordial leads V(1-3) and inferior wall leads may suggest APE diagnosis.

Emergency department and office-based evaluation of patients with chest pain

The management of patients with chest pain is a common and challenging clinical problem. Although most of these patients do not have a life-threatening condition, the clinician must distinguish between those who require urgent management of a serious problem such as acute coronary syndrome (ACS) and those with more benign entities who do not require admission. Although clinical judgment continues to be paramount in meeting this challenge, new diagnostic modalities have been developed to assist in risk stratification. These include markers of cardiac injury, risk scores, early stress testing, and noninvasive imaging of the heart. The basic clinical tools of history, physical examination, and electrocardiography are currently widely acknowledged to allow early identification of low-risk patients who have less than 5% probability of ACS. These patients are usually initially managed in the emergency department and transitioned to further outpatient evaluation or chest pain units. Multiple imaging strategies have been investigated to accelerate diagnosis and to provide further risk stratification of patients with no initial evidence of ACS. These include rest myocardial perfusion imaging, rest echocardiography, computed tomographic coronary angiography, and cardiac magnetic resonance imaging. All have very high negative predictive values for excluding ACS and have been successful in reducing unnecessary admissions for patients at low to intermediate risk of ACS. As patients with acute chest pain transition from the evaluation in the emergency department to other outpatient settings, it is important that all clinicians involved in the care of these patients understand the tools used for assessment and risk stratification.

Uncommon electrocardiographic changes corresponding to symptoms during recurrent pulmonary embolism as documented by computed tomography scans

Electrocardiographic (ECG) findings of pulmonary embolism (PE) include S1Q3T3 pattern, right bundle-branch block, right-axis deviation, and T-wave inversion in medial precordial leads. We report other uncommon ECG changes associated with various symptoms during recurrent PE as documented by computed tomography (CT) scans in a single patients. An 83-year-old woman was admitted with PE secondary to deep venous thrombosis in the left leg. During episodes of chest pain, ECG showed QTc prolongation (480 ms) with new T-wave inversion in leads III, aVF, and V1-V3, and ST-segment depression in leads V5-V6. Despite adequate anticoagulant therapy, recurrent episodes of PE occurred in the hospital. When the patient experienced sudden chest tightness, ECG showed a new S-wave notch in lead V1 and clock-wise rotation with sinus tachycardia. She also experienced transient syncope with hypotension. At this time, ECG showed transient atrioventricular junctional rhythm followed by sinus arrest, and CT scan showed a new massive embolus in the main pulmonary trunk with right ventricular dilatation, as demonstrated by echocardiography. The mechanism responsible for QTc prolongation with ST-T changes, the S-wave notch in lead V1 with clockwise rotation, or atrioventricular junctional rhythm with sinus arrest during PE may be associated with myocardial ischemia, acute right ventricular overload, or vagal reflex, respectively.