Electrocardiogram alterations in non-traumatic brain injury: a systematic review

The presence of abnormal electrocardiograms in individuals without known organic heart disease is one of the most common manifestations of cardiac dysfunction occurring during acute non traumatic brain injury. The primary goal of the present review is to provide an overview of the available data and literature regarding the presence of new-onset electrocardiographic (ECG) alterations in acute non traumatic brain injury. The secondary aim is to identify the incidence of ECG alterations and consider the prognostic significance of new-onset ECG changes in this setting. To do so, English language articles from January 2000 to January 2022 were included from PubMed using the following keywords: "electrocardiogram and subarachnoid hemorrhage", "electrocardiogram and intracranial hemorrhage", "Q-T interval and subarachnoid hemorrhage ", "Q-T interval and intracranial bleeding ", "Q-T interval and intracranial hemorrhage", and "brain and heart- interaction in stroke". Of 3162 papers, 27 original trials looking at electrocardiogram alterations in acute brain injury were included following the PRISMA guideline. ECG abnormalities associated with acute brain injury could potentially predict poor patient outcomes. They could even herald the future development of neurogenic pulmonary edema (NPE), delayed cerebral ischemia (DCI), and even in-hospital death. In particular, patients with SAH are at increased risk of having severe ventricular dysrhythmias. These may contribute to a high mortality rate and to poor functional outcome at 3 months. The current data on ECG QT dispersion and mortality appear less clearly associated. While some patients demonstrated poor outcomes, others showed no relationship with poor outcomes or increased in-hospital mortality. Observing ECG alterations carefully after cerebral damage is important in the critical care of these patients as it can expose preexisting myocardial disease and change prognosis.

Subarachnoidal hemorrhage related cardiomyopathy: an overview of Tako-Tsubo cardiomyopathy and related cardiac syndromes

INTRODUCTION

Subarachnoid hemorrhage (SAH) is caused by a ruptured intracranial aneurysm leading to acute extravasation of blood into the subarachnoid space. SAH has an incidence of 6.3 per 100,000 persons per year in Europe and accounts for 5% of all strokes. SAH occurs at a relatively young age and has poor clinical outcomes and high mortality rates. Cardiac syndromes are regularly seen in patients with acute neurologic disease including SAH. These cardiac complications of SAH are associated with increased morbidity and mortality and present in a large variety and severity.

AREAS COVERED

The main goal of this review is to describe the SAH-related cardiac syndromes. Secondly, we will provide an overview of the underlying pathophysiology regarding the development of cardiac syndromes. Thirdly, we will describe the impact of cardiac syndromes on patient outcome.

EXPERT OPINION

Of all neurology patients, SAH patients have the highest risk of developing takotsubo syndrome (TTS), occurring in about 0.8-30% of patients. Both TTS and neurogenic stunned myocardium have many similarities on echocardiographic evaluation. In European Cardiology consensus, SAH is recognized as a primary cause of TTS.

Assessment of the ECG T-Wave in Patients With Subarachnoid Hemorrhage

BACKGROUND

Prolongation of the interval from the peak to the end of the T wave (Tp-Te) on a 12-lead electrocardiogram (ECG) is associated with ventricular arrhythmias. The aim of this study was to clarify associations between Tp-Te, Tp-Te/QT, and Tp-Te/rate-corrected QT (QTc) with clinical severity of subarachnoid hemorrhage (SAH) and clinical outcomes.

METHODS

This retrospective study included 222 patients with acute SAH (group S) and 306 patients with unruptured cerebral aneurysms (group U). Tp-Te, Tp-Te/QT, and Tp-Te/QTc were manually measured in standard 12-lead ECG recordings on admission and comparisons made between patients in groups S and U. The relationships of these ECG parameters with Hunt and Hess grade and Glasgow outcome scale were analyzed using multiple logistic regression analysis after adjustment for confounding factors.

RESULTS

Tp-Te, Tp-Te/QT, and Tp-Te/QTc were significantly greater in group S than in group U (group S: 109±30, 0.26±0.07, and 0.24±0.06 ms; group U: 84±12, 0.22±0.03, and 0.21±0.03 ms, respectively; P < 0.0001). In addition, in the multiple logistic regression analyses these variables were positively correlated with the Hunt and Hess grade (Tp-Te odds ratio [95% confidence interval], 2.414 [1.375-4.238], P=0.002; Tp-Te/QT, 1.886 [1.085-3.277], P = 0.024; Tp-Te/QTc, 1.873 [1.07-3.278], P=0.028, and negatively correlated with Glasgow outcome scale Tp-Te odds ratio [95% confidence interval], 4.168 [2.409-7.209], P<0.001; Tp-Te/QT, 2.434 [1.413-4.192], P=0.001; Tp-Te/QTc 2.953 [1.703-5.123], P<0.001).

CONCLUSIONS

Tp-Te, Tp-Te/QT, and Tp-Te/QTc are associated with disease severity and clinical outcome in patients with SAH.

Does the Magnitude of the Electrocardiogram QT Interval Dispersion Predict Stroke Outcome?

BACKGROUND

QT dispersion, maximal interlead difference in QT interval on 12-lead electrocardiogram (ECG), measures cardiac repolarization abnormalities. Data are conflicting whether QT dispersion predicts adverse outcome in acute ischemic stroke (AIS) patients. Our objective is to determine if QT dispersion predicts: (1) short-term clinical outcome in AIS, and (2) stroke location (insular versus noninsular cortex).

METHODS

Admission ECGs from 412 consecutive patients with acute stroke symptoms from 2 university-based stroke centers were reviewed. QT dispersion was measured. A neuroradiologist reviewed brain imaging for insular cortex involvement. Favorable clinical outcomes at discharge were modified Rankin Scale (mRS) score of 0-1, discharge National Institutes of Health Stroke Scale (NIHSS) score less than 2, and discharge to home. Multiple logistic regressions were performed for each outcome measure and to determine the association between insular infarct and QT dispersion.

RESULTS

Of 145 subjects in the final analysis, median age was 65 years (interquartile range [IQR] 56-75), male patients were 38%, black patients were 68%, median QT dispersion was 78 milliseconds (IQR 59-98), and median admission NIHSS score was 4 (IQR 2-6). QT dispersion did not predict short-term clinical outcome for mRS score (odds ratio [OR] = 1.001, 95% confidence interval [CI] .99-1.01, P = .85), NIHSS at discharge (OR = .994, 95% CI .98-1.01, P = .30), or discharge disposition (OR = 1.001, 95% CI .99-1.01, P = .81). Insular cortex involvement did not correlate with QT dispersion magnitude (OR = 1.009, 95% CI .99-1.02, P = .45).

CONCLUSIONS

We could not demonstrate that QT dispersion is useful in predicting short-term clinical outcome at discharge in AIS. Further, the magnitude of QT dispersion did not predict insular cortical stroke location.

Relationship between QT interval dispersion in acute stroke and stroke prognosis: a systematic review

BACKGROUND

QT dispersion (QTd) has been proposed as an indirect electrocardiography (ECG) measure of heterogeneity of ventricular repolarization. The predictive value of QTd in acute stroke remains controversial. We aimed to clarify the relationship between QTd and acute stroke and stroke prognosis.

METHODS

A systematic review of the literature was performed using prespecified medical subjects heading terms, Boolean logic, and the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. Eligible studies included ischemic or hemorrhagic stroke and provided QTd measurements.

RESULTS

Two independent reviewers identified 553 publications. Sixteen articles were included in the final analysis. There were a total of 888 stroke patients: 59% ischemic and 41% hemorrhagic. There was considerable heterogeneity in study design, stroke subtypes, ECG assessment time, control groups, and comparison groups. Nine studies reported a significant association between acute stroke and baseline QTd. Two studies reported that QTd increases are specifically related to hemorrhagic strokes, involvement of the insular cortex, right-side lesions, larger strokes, and increases in 3,4-dihydroxyphenylethylene glycol in hemorrhagic stroke. Three studies reported QTd to be an independent predictor of stroke mortality. One study each reported increases in QTd in stroke patients who developed ventricular arrhythmias and cardiorespiratory compromise.

CONCLUSIONS

There are few well-designed studies and considerable variability in study design in addressing the significance of QTd in acute stroke. Available data suggest that stroke is likely to be associated with increased QTd. Although some evidence suggests a possible prognostic role of QTd in stroke, larger and well-designed studies need to confirm these findings.

Anesthesia induction with sevoflurane and propofol: evaluation of P-wave dispersion, QT and corrected QT intervals

The present study compared the effects of anesthesia induction with sevoflurane and propofol on hemodynamics, P-wave dispersion (Pwd), QT interval and corrected QT (QTc) interval. A total of 72 adult patients were included in this prospective study. All patients had control electrocardiograms (ECGs) before anesthesia induction. Anesthesia was induced with sevoflurane inhalation or intravenous propofol. Electrocardiography for all patients was performed during the 1(st) and 3(rd) minutes of induction, 3 minutes after administration of muscle relaxant, and at 5 minutes and 10 minutes after intubation. Pwd and QT intervals were measured on all ECGs. QTc intervals were determined using the Bazett formula. There was no significant difference in Pwd and QT and QTc intervals on control ECGs. In the sevoflurane group, except for control ECGs, Pwd and QTc interval on all ECGs were significantly longer than those in the propofol group (p < 0.05). We conclude that propofol should be used for anesthesia induction in patients with a predisposition to preoperative arrhythmias, and in those whose Pwd and QTc durations are prolonged on preoperative ECGs.

Preoperative abnormal P and QTc dispersion intervals in patients with metabolic syndrome

We evaluated P wave dispersion (Pwd), QT, corrected QT (QTc), QT dispersion, and corrected QT dispersion (QTcd) intervals in patients with metabolic syndrome (MetS). Patients scheduled to undergo elective noncardiac surgery were included in the study. The main diagnoses, anthropometric measurements, waist circumferences, body mass index, electrocardiograms, serum levels of electrolytes, glucose, and lipids were recorded for all patients. QTc, QTcd intervals were determined with the Bazett formula. MetS (group M, n = 36) was diagnosed using the Adult Treatment Panel III. Controls (group C, n = 40) were chosen on the basis of patients with no MetS and matched for age and gender. There were no differences between groups in terms of age, sex, or serum electrolyte levels (P > 0.05). Waist circumferences, body mass index, serum glucose, and triglyceride values in group M were significantly higher than those in group C (P < 0.001). In group M, Pwd, QTc, QT dispersion and QTcd intervals were significantly longer than those in group C (P < 0.001). This finding and our retrospective analysis suggest that these patients may be at greater risk of perioperative arrhythmias.