Differences in negative T waves between acute pulmonary embolism and acute coronary syndrome

T Wave Inversion: A Screening Tool for Rapidly Differentiating Acute Coronary Syndrome and Pulmonary Embolism

Introduction Acute coronary syndrome (ACS) and acute pulmonary embolism (PE) are life-threatening conditions with similar clinical presentations. As current diagnostic tools, such as computed tomography pulmonary angiography, for distinguishing between these two conditions are time-consuming and may not be available in all settings, we tried in this study to devise a diagnostic tool based on electrocardiography to distinguish between ACS and acute PE based on T wave features. Methods Medical records of patients with diagnoses of ACS and acute PE, who were referred to three hospitals affiliated with Shiraz University of Medical Sciences, Shiraz, Iran, from March 2019 to March 2021, were evaluated. One expert cardiologist read patients' electrocardiograms (ECGs). All ECGs were recorded at the standard 25 mm/s and 10 mm/mV. The sum of T wave inversion or TWI (mV) in consecutive leads, including anterior leads (V1, V2, V3, and V4), inferior leads (II, III, aVF), and lateral leads (I, aVL, V5, and V6) were calculated to estimate the cut-off points used to differentiate ACS versus acute PE. The receiver operating characteristic (ROC) curve was used to estimate the diagnostic accuracy of T wave changes. The Youden index was used to calculate the optimum cut-offs for sensitivity and specificity. Results Of 151 patients with a mean age of 55.44±12.88 years, 74 were in the acute PE and 77 were in the ACS groups. The results showed that the TWI sum in anterior leads >1.2 mV (P<0.001), in lateral leads >0.9 mV (P<0.001), in anterior-to-inferior leads ratio >12 (P<0.001), and V4/V1 leads ratio >4 (P<0.001) rules out acute PE. Anterior-to-lateral TWI ratio (AUC=0.807, sensitivity=70.3%, specificity=10%) was significantly distinctive among ACS and acute PE patients. Conclusion TWI sum in anterior leads >1.2 mV, in lateral leads >0.9 mV, in anterior-to-inferior leads ratio >12, and in V4/V1 leads ratio >4 rules out acute PE. The anterior-to-lateral TWI ratio obtained from patients' ECG was significantly distinctive among the patients and can be used as a screening tool.

Saddle Pulmonary Embolism Detected by Transthoracic Echocardiography in a Patient With Suspected Myocardial Infarction

•PE is very rarely identified on TTE. •Saddle PE does not represent a higher-risk subset of PE. •Catheter-based therapies are becoming more commonplace in the management of acute PE.

An Older Patient With Chest Pain-Diagnostic Traps

This case report describes an older patient with persistent chest pain, recent hospitalization for SARS-CoV-2 infection, and previous kidney transplantation.

Index of cardiac-electrophysiological balance and the effects of thrombolytic therapy on the electrocardiogram of patients with pulmonary embolism

OBJECTIVE

Different parameters on electrocardiograms (ECG) have been investigated to predict arrhythmia and mortality in patients with acute pulmonary embolism (APE). The acute effect of thrombolytic therapy (TT) on these parameters has not been investigated yet.

METHODS

We examined the data of 83 patients who were evaluated as high-risk APE and discharged from the hospital after TT. First, the high-risk APE patients' ECGs were compared with healthy control subjects (n = 55). After their admission and 24 hours later, the ECGs of patients with APE were compared. Heart rate, P-wave morphology, QRS duration, QT distance, Tp-e, and the index of cardiac electrophysiological balance (iCEB) were analyzed.

RESULTS

Although P maximum was not different between the groups' ECGs, heart rate, QT, QTc (corrected QT) interval, Tp-e intervals, Tp-e/QT ratio, and P wave dispersion were significantly higher in the APE group ( P values < 0.031). iCEB or iCEBc (corrected iCEB) values were lower in APE group ( P < 0.001). After TT, we determined a decrease in heart rate, Tp-e interval, and Tp-e/QT ratio ( P < 0.001). Although we detected a decrease in the QT and QTc interval and QT dispersion (QTd), QTd had no statistical significance (respectively P -value 0.013, 0.029, and 0.096). The iCEB and iCEBc levels were lower after TT ( P -value was 0.035 and 0.044 respectively).

CONCLUSION

The QT, QTc, Tp-e interval, Tp-e/QTc ratio, iCEB, and iCEBc values significantly decreased after TT. It may be thought that effective TT causes partial improvement in ventricular repolarization in an early period.

Usefulness of a Novel Electrocardiographic Score to Estimate the Pre-Test Probability of Acute Pulmonary Embolism

According to our experience the 12-lead electrocardiogram (ECG) may be used to estimate the pretest probability of acute pulmonary embolism (acPE). To this end, we devised a novel ECG score (nECGs) composed of 5 known ECG criteria, best characterizing the key pathogenetic steps of acPE. A retrospective derivation cohort including 136 patients with acPE and a prospective validation cohort including 149 consecutive patients were used to devise and validate the nECGs. The latter cohort consisted of 76 patients with acPE and 73 controls presenting with characteristic symptoms of acPE, in whom the work-up ruled out acPE. We compared the diagnostic value of our nECGs with those of another ECG score (Daniel-ECG-score) and of the best prediction rules (3 Wells score and 2 Geneva score variants). The sensitivity (98.7%), negative predictive value (98%), test accuracy (84.4%) and the negative likelihood ratio (LR) (0.019) of the nECGs were superior to those of all other investigated methods. There was no between-groups difference in the positive LR. The specificity (69%) of the nECGs was inferior to those of the Daniel-ECG-score and Wells scores and did not differ or was superior to those of the Geneva score variants. The positive predictive value (77.3%) of the nECGs was superior to those of the 2 Geneva scores and did not differ from those of the other methods. In conclusion, the nECGs due to its superior sensitivity, negative predictive value, test accuracy, and negative LR estimated the pretest probability of acPE better than the Daniel-ECG-score and the prediction rules.

Impact of COVID-19 on the Cardiovascular System: A Review

The recent outbreak of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 has been declared a public health emergency of international concern. COVID-19 may present as acute respiratory distress syndrome in severe cases, and patients with pre-existing cardiovascular comorbidities are reported to be the most vulnerable. Notably, acute myocardial injury, determined by elevated high-sensitivity troponin levels, is commonly observed in severe cases, and is strongly associated with mortality. Therefore, understanding the effects of COVID-19 on the cardiovascular system is essential for providing comprehensive medical care for critically ill patients. In this review, we summarize the rapidly evolving data and highlight the cardiovascular considerations related to COVID-19.

Comparison between Negative T waves characteristics in acute coronary syndrome and pulmonary embolism

BACKGROUND

Electrocardiogram (ECG) is the first available modality used in patients with chest pain and dyspnea in emergency rooms. We aimed to study differences between acute coronary syndrome (ACS) and acute pulmonary embolism (APE) in patients presented primarily with abnormal negative T waves on their admission Electrocardiogram.

METHODS

This research was a retrospective study in which 297 patients (97 patients with APE and 200 with ACS) were included. The patients were admitted to the emergency ward of a tertiary heart center between 2015 and 2017. In addition to the evaluation of distribution of negative T waves, the depth of the inverted precordial T waves was measured.

RESULTS

The mean age of patients was 62.0 ± 11.4 in ACS group and 60.7 ± 17.6 in APE group (P value = 0.563). Total negative T in V3 and V4 in ACS and APE groups was 9.1 mm and 4.2 mm respectively (P value <0.001). Total magnitude of negative T in anterior leads divided by total magnitude of negative T in inferior leads for ACS and APE groups were 15.1 ± 12.0 and 5.4 ± 3.6 respectively (P value = 0.001). ROC curves showed that total magnitude of negative T in V4 divided by negative T in V1 can be valuable. A cutoff point of 1.75 with sensitivity of 73.5% and specificity of 84.9% (95% CI 0.79-0.91 P < 0.001) could differentiate APE patients from ACS patients.

CONCLUSION

This study suggests that total magnitude of negative T in left precordial leads divided by right precordial leads can be valuable in differentiating APE from ACS.

Diagnostic value of the corrected QT difference between leads V1 and V6 in patients with acute pulmonary thromboembolism

In acute pulmonary thromboembolism (PTE), right ventricular pressure overload impairs right-sided cardiac conduction and repolarization. We hypothesized that if heterogeneity of repolarization between right and left ventricles occurs in acute PTE, there would be the difference of repolarization between them. Therefore, we aimed to evaluate the diagnostic value of corrected QT interval (QTc) difference between leads V1 and V6 (V1 - V6) in patients with acute PTE.A total of 89 patients with suspected acute PTE who underwent computed tomographic angiography (CTA) were enrolled from January to December 2015. PTE was identified by CTA. We compared electrocardiographic (ECG) parameters, especially QTc difference (V1 - V6) between patients with PTE and those without PTE.Acute PTE was finally diagnosed in 45 patients. Clinical situations including the chief complaint were not different between PTE and non-PTE groups. S1Q3T3, a traditional ECG marker, had no diagnostic value for acute PTE. Patients with PTE had a significantly longer mean QTc in V1 (454.6 ± 44.3 vs 417.5 ± 31.3 ms, P < .001) and larger QTc difference (V1 - V6) (34.8 ± 30.5 vs -12.5 ± 16.6 ms, P < .001) than non-PTE controls. QTc difference (V1 - V6) was negative in all patients without PTE. PTE patients had a higher prevalence of T wave inversion in leads III (51.1% vs 29.5%, P = .038) and V1 (82.2% vs 38.6%, P < .001). A QTc difference (V1 - V6) of ≥20 ms identified PTE with 82.2% sensitivity, 100.0% specificity, and 100.0% positive predictive value.QTc difference (V1 - V6) had an excellent diagnostic value for differentiating patients with and without acute PTE.

Chest pain with giant global T wave inversions and extreme QT prolongation

Negative T waves in electrocardiography have been widely studied. We presents a case of Wellens' syndrome which is a pattern of global inverted T waves with QT prolongation on ECG due to transient proximal LAD occlusion and pointed out other differential diagnosis.

Implications of Using the Cabrera Sequence for Diagnosing Acute Coronary Syndrome

The 12-lead electrocardiogram (ECG) is the important, initial examination for diagnosing acute coronary syndrome (ACS). In the traditional 12-lead ECG display, the precordial leads are displayed in their anatomically contiguous order, which makes it easy to understand the positional relationships between the precordial leads and the heart, but the limb leads are not. The "Cabrera sequence" displays the limb leads in an anatomically contiguous manner, which facilitates understanding of the positional relations between the limb leads and the heart, resulting in more rapid, easy, and accurate ECG interpretation than the traditional limb leads display. This review explores the clinical advantages of the Cabrera sequence as compared with the traditional limb leads display for the diagnosis of ACS. (Circ J 2016; 80: 1087-1096).