Transient QT interval prolongation with inverted T waves indicates myocardial salvage on dual radionuclide single-photon emission computed tomography in acute anterior myocardial infarction

Temporal electrocardiographic changes in anterior ST elevation myocardial infarction versus the Takotsubo syndrome

Background

Electrocardiography (ECG) on admission is similar in ST elevation myocardial infarction (STEMI) and Takotsubo syndrome (TTS). ECG on admission has been extensively investigated and compared between STEMI and TTS, however, only a few studies have compared temporal ECG. Our aim was to compare ECG in anterior STEMI versus female TTS from admission to day 30.

Methods

Adult patients with anterior STEMI or TTS treated at Sahlgrenska University Hospital (Gothenburg, Sweden) from December 2019 to June 2022 were prospectively enrolled. Baseline characteristics, clinical variables and ECGs from admission to day 30 were analyzed. Using a mixed effects model, we compared temporal ECG between female patients with anterior STEMI or TTS, as well as between female and male patients with anterior STEMI.

Results

A total of 101 anterior STEMI patients (31 female, 70 male) and 34 TTS patients (29 female, 5 male) were included. The temporal pattern of T wave inversion was similar between female anterior STEMI and female TTS, as well as between female and male anterior STEMI. ST elevation was more common, whereas QT prolongation was less common, in anterior STEMI compared with TTS. Q wave pathology was more similar between female anterior STEMI and female TTS than between female and male anterior STEMI.

Conclusions

The pattern of T wave inversion and Q wave pathology from admission to day 30 was similar in female patients with anterior STEMI and female patients with TTS. Temporal ECG in female patients with TTS may be interpreted as following a "transient ischemic" pattern.

ECG differences and ECG predictors in patients presenting with ST segment elevation due to myocardial infarction versus takotsubo syndrome

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Takotsubo syndrome and myocardial infarction can present with ST segment elevation.

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ECG in Takotsubo resembles left anterior descending artery myocardial infarction.

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Ventricular arrhythmia or death occur in both Takotsubo and myocardial infarction.

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ST segment changes predict ventricular arrhythmia or death in myocardial infarction.

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ST segment changes do not predict ventricular arrhythmia in Takotsubo syndrome.

Background

Previous studies comparing electrocardiogram (ECG) in Takotsubo syndrome (TS) versus ST elevation myocardial infarction (STEMI) included TS patients without ST elevation, did not consider the culprit lesion in STEMI or had groups that were unbalanced regarding sex and age. Accounting for these factors, we sought to conduct a more reliable comparison of ECG in TS with ST-elevation (STE-TS) versus STEMI. The secondary aim was to investigate if ST segment changes, T wave inversion or prolonged QT interval predicted ventricular arrhythmia or death in STE-TS and STEMI.

Methods

All STE-TS patients who presented at Sahlgrenska University Hospital between 2008 and 2019 were matched by sex and age to STEMI patients. STEMI patients were subcategorized according to whether or not the culprit lesion was located in the left anterior descending artery (LAD). Baseline characteristics, in‐hospital outcomes and admission ECGs were analyzed.

Results

104 STE-TS patients were sex- and age-matched with 274 STEMI patients (113 LAD-STEMI, 161 non-LAD STEMI). Admission ECG in STE-TS was more similar to LAD STEMI than non-LAD STEMI. Reciprocal ST depression was less common in STE-TS (7/104, 6.7%) compared with STEMI (112/274, 41%; p= < 0.001). The sum of all ST elevations and the sum of all ST-deviations predicted life-threatening ventricular arrhythmia (LTVA) or death in LAD STEMI but not in STE-TS.

Conclusions

In conclusion, admission ECG in STE-TS was similar to LAD STEMI but reciprocal ST depression was less common in STE-TS compared with STEMI overall. ST segment changes predicted LTVA or death in STEMI but not in STE-TS.

Hydroxychloroquine reduces interleukin-6 levels after myocardial infarction: The randomized, double-blind, placebo-controlled OXI pilot trial

OBJECTIVES

To determine the anti-inflammatory effect and safety of hydroxychloroquine after acute myocardial infarction.

METHOD

In this multicenter, double-blind, placebo-controlled OXI trial, 125 myocardial infarction patients were randomized at a median of 43 h after hospitalization to receive hydroxychloroquine 300 mg (n = 64) or placebo (n = 61) once daily for 6 months and, followed for an average of 32 months. Laboratory values were measured at baseline, 1, 6, and 12 months.

RESULTS

The levels of interleukin-6 (IL-6) were comparable at baseline between study groups (p = 0.18). At six months, the IL-6 levels were lower in the hydroxychloroquine group (p = 0.042, between groups), and in the on-treatment analysis, the difference at this time point was even more pronounced (p = 0.019, respectively). The high-sensitivity C-reactive protein levels did not differ significantly between study groups at any time points. Eleven patients in the hydroxychloroquine group and four in the placebo group had adverse events leading to interruption or withdrawal of study medication, none of which was serious (p = 0.10, between groups).

CONCLUSIONS

In patients with myocardial infarction, hydroxychloroquine reduced IL-6 levels significantly more than did placebo without causing any clinically significant adverse events. A larger randomized clinical trial is warranted to prove the potential ability of hydroxychloroquine to reduce cardiovascular endpoints after myocardial infarction.

Risk of in-hospital life-threatening ventricular arrhythmia or death after ST-elevation myocardial infarction vs. the Takotsubo syndrome

Aims

The risk of life‐threatening ventricular arrhythmias (LTVA) has been reported to be lower in Takotsubo syndrome (TS) compared with ST‐elevation myocardial infarction (STEMI). However, the extent to which these differences relate to the fact that most patients with TS are women (who have a lower risk of LTVA) and a relatively larger proportion of patients with STEMI are men is incompletely understood. We aimed to investigate the risk of LTVA or death in sex‐matched and age‐matched patients with TS, anterior STEMI, and non‐anterior STEMI.

Methods and results

We systematically reviewed the charts of all patients with TS who were treated at Sahlgrenska University Hospital (Gothenburg, Sweden) between 2008 and 2019. A total of 155 patients with confirmed TS (according to the European Society of Cardiology diagnostic criteria for TS) were sex‐matched and age‐matched 1:1:1 to patients with anterior and non‐anterior STEMI. Baseline characteristics and in‐hospital outcomes were recorded directly from the patient charts for all patients, and all admission electrocardiographs were analysed. The primary outcome was the composite of death or LTVA [defined as sustained ventricular tachycardia (>30 s) or ventricular fibrillation] within 72 h. The risk of LTVA or death within 72 h after admission was considerably lower in TS (2.6%) vs. anterior STEMI (14%; P = 0.002) and non‐anterior STEMI (9.0%; P = 0.02), despite similar or greater risks of acute heart failure, and similar risks of cardiogenic shock. Compared with STEMI, TS was associated with a lower risk of sustained and non‐sustained ventricular tachycardia and ventricular fibrillation.

Conclusions

In a predominantly female age‐matched and sex‐matched cohort of patients with TS, anterior STEMI, and non‐anterior STEMI, the adjusted risk of in‐hospital LTVA or death was considerably lower in TS compared with STEMI, despite similar or greater risk of acute heart failure and similar risk of cardiogenic shock.

Dynamic changes of QTc interval and prognostic significance in takotsubo (stress) cardiomyopathy

BACKGROUND

Prolonged QT corrected (QTc) intervals are associated with adverse cardiovascular outcomes both in healthy and high-risk populations. Our objective was to evaluate the QTc intervals during a takotsubo cardiomyopathy (TTC) episodes and their potential prognostic role.

HYPOTHESIS

Dynamic changes of QTc interval during hospitalization for TTC could be associated with outcome at follow-up.

METHODS

Fifty-two consecutive patients hospitalized for TTC were enrolled. Twelve-lead electrocardiogram (ECG) was performed within 3 h after admission and repeated after 3, 5, and 7 days. Patients were classified in 2 groups: group 1 presented the maximal QTc interval length at admission and group 2 developed maximal QTc interval length after admission.

RESULTS

Mean admission QTc interval was 493 ± 71 ms and mean QTc peak interval was 550 ± 76 ms (P < 0.001). Seventeen (33%) patients were included in group 1 and 35 (67%) patients in group 2. There were no differences for cardiovascular risk factors and in terms of ECG findings such as ST elevation, ST depression, and inverted T waves. Rates of adverse events during hospitalization among patients of group 1 and 2 were different although not significantly (20% vs 6%, P = 0.22). After 647 days follow-up, patients of group 1 presented higher risk of cardiovascular rehospitalization (31% vs 6%, P = 0.013; log-rank, P < 0.01). At multivariate analysis, including age and gender, a prolonged QTc interval at admission was significantly associated with higher risk of rehospitalization at follow-up (hazard ratio: 1.07 every 10 ms, 95% confidence interval: 1.003-1.14, P = 0.04).

CONCLUSIONS

Prolonged QTc intervals at admission during a TTC episode could be associated with a higher risk of cardiovascular rehospitalization at follow-up. Dynamic increase of QTc intervals after admission are characterized by a trend toward a better prognosis.

Delayed Normalization of Electrocardiograms in Patients with Takotsubo Cardiomyopathy due to Aneurysmal Subarachnoid Hemorrhage

BACKGROUND

Takotsubo cardiomyopathy (TCM) is caused by excessive physical and mental stress, and sometimes causes potentially fatal arrhythmias such as torsades de pointes. This study characterized the features of TCM due to aneurysmal subarachnoid hemorrhage, particularly the delayed normalization of electrocardiograms compared with that of transthoracic echocardiograms.

METHODS

Ten patients with TCM were selected from the 450 patients with subarachnoid hemorrhage treated in our hospital between January 2007 and November 2015. We retrospectively examined these 10 patients with regard to various factors, including durations of abnormal electrocardiographic and echocardiographic findings.

RESULTS

All 10 patients were women. Mean age at diagnosis was 69.3 years (range, 40-90 years). Electrocardiographic findings were as follows: inverted or flattened T waves (100%); QTc prolongation >0.45 seconds (90.0%); ST segment elevation (60.0%); and ST segment depression (20.0%). Echocardiograms showed typical findings of TCM in 9 cases and inverted TCM in 1 case. In 1 case, ventral fibrillation was observed. Normalization of electrocardiograms was consistently delayed compared with that of echocardiograms, by more than 3 weeks in at least 5 cases (50%). If follow-up of electrocardiographic parameters is discontinued at the point of normalization of wall motion and the end of the vasospasm period, fatal arrhythmia may occur in the aftermath.

CONCLUSIONS

This study showed a notable delay in recovery of abnormal electrocardiographic findings compared with the recovery of echocardiographic findings. Sufficient attention to persistent abnormalities on electrocardiography is warranted, even after improvements in cardiac wall motion and the vasospasm period.

Prolonged QT and myocardium recovery after primary PCI: a cMRI study

BACKGROUND

The presence of viable stunned myocardium recovering after primary angioplasty is not easy to identify in the early phase of acute myocardial infarction (AMI) by noninvasive bed-side methods. We therefore aimed to assess whether a simple electrocardiogram parameter may be of help in identifying the presence of stunned viable myocardium recovering after reperfusion with primary angioplasty.

MATERIALS AND METHODS

A total of 14 consecutive patients with ST-elevation AMI (STEMI) were enrolled in the study and underwent QT duration assessment after admission: the difference between QT corrected (QTc) in the ischaemic areas and QTc values in nonischaemic areas was therefore calculated and compared with the presence and the extension of viable stunned myocardium, assessed by comparing akinetic/dyskinetic areas at admission echocardiography with akinetic/dyskinetic areas and extension of scar at 6-month cardiac magnetic resonance imaging (cMRI).

RESULTS

In subjects with viable recovering myocardium, 75% had a QTc max > 440 ms (vs. 17%, P = 0·03); higher differential QTc values and smaller scar areas were found (33 ms vs. -17 ms, 14% vs. 27%, P = 0·03, 0·06 respectively). Differential QTc values > 0 were able to identify the presence of viable myocardium with an odds ratio of 35 (P < 0·05, sensitivity 88%, specificity 83%, positive predictive power 88%, negative predictive power of 83%). Differential QTc values were related to the extension of viable recovering myocardium (P < 0·001).

CONCLUSION

Viable myocardium recovering after primary angioplasty in STEMI may be predicted by the presence of increased QTc values in ischaemic areas in comparison with nonischaemic areas.

Prevalence and prognostic significance of long QT interval in patients with acute coronary syndrome: review of the literature

BACKGROUND

Sympathetic hyperactivity is linked with several adverse cardiovascular events in patients with acute coronary syndrome (ACS). Sympathetic activity increases early in the process of ischemia through 2 mechanisms. One originates from the central nervous system and leads to enhanced sympathetic activity. The other mechanism originates at the infarct zone and leads to B receptor up-regulation and catecholamine supersensitivity. Nevertheless, sympathetic hyperactivity accompanied by an underlying myocardial structural damage is likely to increase the ventricular repolarization duration measured as QT interval on the body surface electrocardiogram.

PURPOSE

The aims of the current review of the literature were to examine the physiological processes underlying the use of long QT interval as a risk prediction tool in patients with ACS and to critically review and critique the existing evidence related to this matter.

CONCLUSION

The available evidence is contradictory and includes serious limitations in design and QT measurement and correction. Until accurate and reliable data are available, it is difficult to determine the additional clinical value and prognostic significance of long QT interval in patients with ACS beyond that in other patients.

CLINICAL IMPLICATIONS

Long QT interval is not uncommon among patients with ACS. Automated continuous QT interval monitoring is superior to manual QT interval measurement with the standard 10-second electrocardiogram. Optimum care for patients with ACS requires nurses to keep monitoring the QT interval several days after the initial event.

Electrocardiographic Findings in Takotsubo Cardiomyopathy: ECG Evolution and Its Difference from the ECG of Acute Coronary Syndrome

BACKGROUND

Electrocardiogram (ECG) manifestations of takotsubo cardiomyopathy (TC) produce ST-segment elevation or T-wave inversion, mimicking acute coronary syndrome (ACS). We describe the ECG manifestation of TC, including ECG evolution, and its different points from ACS.

METHODS

We studied 37 consecutive patients (age 67 ± 15 years, range 23–89, M:F = 12:25) from March 2004 to November 2012 with a diagnosis of TC who were proven to have apical ballooning on echocardiography or left ventricular angiography and normal coronary artery. We analyzed their standard 12-lead ECGs, including rate, PR interval, QRS duration, corrected QT (QTc) interval, ECG evolutions, and arrhythmia events.

RESULTS

Two common ECG findings in TC were ST-segment elevation (n = 13, 35%) and T inversion (n = 24, 65%), mostly in the precordial leads. After ST-segment resolution, in a few days (3.5 days), diffuse and often deep T-wave inversion developed. Eight patients (22%) had transient Q-waves lasting a few days in precordial leads. No reciprocal ST-segment depression was noted. T-wave inversion continued for several months. QT prolongation (<440 milliseconds) was observed in 37 patients (97%). There were no significant life-threatening arrhythmias except atrial fibrillation (n = 6, 16%).

CONCLUSION

There are distinct differences between the ECGs of TC and ACS. These differences will help to differentiate TC from ACS.

Specific findings of the standard 12-lead ECG in patients with 'Takotsubo' cardiomyopathy: comparison with the findings of acute anterior myocardial infarction

The clinical course of 'Takotsubo' cardiomyopathy closely resembles that of acute myocardial infarction (AMI) and coronary angiography (CAG) is usually performed to distinguish the 2 conditions during the acute phase. The present study was designed to determine whether the standard 12-lead electrocardiogram (ECG) findings could help to distinguish 'Takotsubo' cardiomyopathy from anterior AMI. The study group comprised 13 patients with 'Takotsubo' cardiomyopathy and 13 consecutive patients with anterior AMI. Patients with 'Takotsubo' cardiomyopathy had abnormal Q waves less frequently than patients with anterior AMI (15% vs 69%, p=0.008). No reciprocal changes were seen in the inferior leads in patients with 'Takotsubo' cardiomyopathy (p=0.0003). The ratio of ST-segment elevation in leads V(4-6) to V(1-3) (SigmaSTeV(4-6)/V(1-3)) was significantly higher in patients with 'Takotsubo' cardiomyopathy (1.55+/-0.53 vs 0.57+/-0.58, p=0.0004). The QTc interval was significantly longer in patients with 'Takotsubo' cardiomyopathy. The absence of reciprocal changes, absence of abnormal Q waves, and a SigmaSTeV(4-6)/V(1-3) >/=1 all showed a high sensitivity and specificity for diagnosing 'Takotsubo' cardiomyopathy. Furthermore, the combination of the absence of reciprocal changes and a SigmaSTeV(4-6)/V (1-3) >/=1 had a greater specificity (100%) and overall accuracy (91%) than either criteria. Therefore, the standard 12-lead ECG on admission can help to distinguish 'Takotsubo' cardiomyopathy from anterior AMI.