Electrocardiogram Changes Research Articles

Clinical Profile and Short-Term Outcomes of Patients Admitted with Acute Pulmonary Embolism in a Tertiary Care Centre

Background: Venous thromboembolism is a major contributor to the global disease burden, with an incidence of around 10 million cases per year and substantially associated morbidity and mortality. Objectives: The study aimed to assess the clinical, laboratory, and radiological profile along with electrocardiogram and echocardiogram changes and the treatment and outcomes in patients admitted with acute pulmonary embolism (PE) in a tertiary care centre. The etiologies and risk factors of the same were also evaluated. Materials and Methods: This was a hospital-based prospective observational study conducted among 31 patients over a period of 18 months. The study was conducted at a tertiary care centre in the Department of General Medicine. Patients of age more than 12 years, admitted with a confirmed diagnosis of acute PE based on computed tomography pulmonary angiography (CTPA), were included in the study. Results: Thrombolysis was done in 12.9% cases, while anticoagulants were given in 87.1% cases. Oxygen therapy was required in 74.2% cases on day 1 while in 9.7% on day 30. Secondary pulmonary hypertension was the commonest complication observed in the study, in 54.8% cases. Severe hypoxia was seen in 35.4% cases. No complications were seen in 6.4% cases. Mortality was recorded in 9.6% of the cases. Conclusion: Since PE is among the leading causes of death and disability, there should be a high degree of suspicion in all clinical settings. And since prolonged immobilisation is a strong risk factor for PE patients at risk, they should be offered prophylactic anticoagulation.

Berberine efficacy against Doxorubicin-induced cardiotoxicity: A systematic review

Cardiotoxicity is one of the main complications of chemotherapy that increases morbidity and mortality in cancerous patients. The present systematic review aimed to investigate the protective effects of berberine (Ber) on doxorubicin (Dox)-induced cardiotoxicity. The study protocol was developed following the PRISMA statement. An extensive search was performed in multiple databases, including Embase, PubMed, Cochrane library, Web of Science, and Scopus. After defining the inclusion/exclusion criteria of the study, 12 records were included. The desired data of the retrieved articles were extracted from the studies and imported into an Excel form and ultimately, the effects, probable outcomes and mechanisms were surveyed. By activating sirtuin 1 (SIRT1), Ber caused reduced oxidative damage and loss of mitochondria integrity in cardiomyocytes. It also regulated autophagy and apoptosis via down-regulating AMP-activated protein kinase (AMPK), nucleotide-binding oligomerization domain, leucine rich repeat, and pyrin domain containing protein (NLRP) activation. Moreover, Ber increased superoxide dismutase (SOD), catalase (CAT), and plasma glutathione peroxidase (GSH-Px) activities, reduced the levels of malondialdehyde (MDA), up-regulated SIRT3, and subsequently reduced oxidative stress in cardiomyocytes and loss of mitochondria integrity, leading to developed apoptosis and regulating the histopathological and electrocardiogram changes in the myocardium. It also ameliorated the DOX-induced calcium ions (Ca2+) and iron overload. Ber reduced oxidant and inflammatory activity, and regulated apoptosis of cardiomyocytes, thus protecting the cells against DOX-induced cardiotoxicity.

A vigilance estimation method for high-speed rail drivers using physiological signals with a two-level fusion framework

The vigilance decrement of high-speed rail (HSR) drivers is one of the main factors contributing to accidents. It’s necessary to develop an effective and reliable method to estimate HSR drivers’ vigilance. Given that response speed is one of the most important capabilities of HSR drivers, the reaction time (RT) of signal detection would be an objective indicator of vigilance. We explored the relationship between RTs and self-reported Karolinska Sleepiness Scale (KSS) scores. And analyzed the change of electroencephalogram (EEG) and electrocardiogram (ECG) features with RTs. Then, a regression model with two-level fusion was proposed to continuously evaluate HSR drivers’ vigilance by estimating their RTs. In the feature-level fusion, a convolutional neural network (CNN) module was used to fuse selected EEG and ECG. Then, EEG, ECG, and fused features were fed into three long short-term memory (LSTM) models to calculate HSR drivers’ RTs in parallel. In the decision-level fusion, a threshold filter was performed on the sub-results of three long short-term memory (LSTM) models to calculate the weights, and the final result was fused with the sub-results with a linear regression (LR) model. Data of 30 HSR drivers in a simulated experiment were used to validate our proposed method. The mean absolute error (MAE), root mean square error (RMSE), and Pearson correlation coefficient (PCC) of our model were 80.13 ms, 109.42 ms, and 0.83, respectively. The results indicated that the estimation accuracy and reliability were improved significantly. This method would make some contributions to developing HSR driver vigilance monitoring systems.

Changes of electrocardiograms of animals with epinephrine heart damage in influences of stress and castration

Changes of electrocardiograms of animals with epinephrine heart damage in influences of stress and castration

Ventricular Septal Defect Exposure by Tricuspid Valve Chordal Detachment-A Retrospective Matched Study.

Background: Transatrial approach is the standard method in repairing ventricular septal defects (VSD) in the pediatric population. However, the tricuspid valve (TV) apparatus might obscure the inferior border of the VSD risking the adequacy of repair by leaving residual VSD or heart block. Detachment of the TV chordae has been described as an alternative technique to TV leaflet detachment. The aim of this study is to investigate the safety of such a technique. Methods: Retrospective review of patients who underwent VSD repair between 2015 and 2018. Group A (n = 25) had VSD repair with TV chordae detachment were matched for age and weight to group B (n = 25) without tricuspid chordal or leaflet detachment. Electrocardiogram (ECG) and echocardiogram at discharge and at 3 years of follow-up were reviewed to identify new ECG changes, residual VSD, and TV regurgitation. Results: Median ages in groups A and B were 6.13 (IQR 4.33-7.91) and 6.33 (4.77-7.2) months. New onset right bundle branch block (RBBB) was diagnosed at discharge in 28% (n = 7) of group A versus 56% (n = 14) in group B (P = .044), while the incidence dropped to 16% (n = 4) in group A versus 40% (n = 10) in group B (P = .059) in the 3 years follow-up ECG. Echocardiogram at discharge showed moderate tricuspid regurgitation in 16% (n = 4) in group A and 12% (n = 3) in group B (P = .867). Three years of follow-up echocardiography revealed no moderate or severe tricuspid regurgitation and no significant residual VSD in either group. Conclusion: No significant difference in operative time was observed between the two techniques. TV chordal detachment technique reduces the incidence of postoperative RBBB without increasing the incidence of TV regurgitation at discharge.

Novel insights in the pathomechanism of Brugada syndrome and fever-related type 1 ECG changes in a preclinical study using human-induced pluripotent stem cell-derived cardiomyocytes.

Brugada syndrome (BrS) is causing sudden cardiac death (SCD) mainly at young age. Studying the underlying mechanisms associated with BrS type I electrocardiogram (ECG) changes in the presence of fever and roles of autophagy for BrS remains lacking. We sought to study the pathogenic role of an SCN5A gene variant for BrS with fever-induced type 1 ECG phenotype. In addition, we studied the role of inflammation and autophagy in the pathomechanism of BrS. Human-induced pluripotent stem cell (hiPSC) lines from a BrS patient harboring a pathogenic variant (c.3148G>A/p. Ala1050Thr) in SCN5A and two healthy donors (non-BrS) and a CRISPR/Cas9 site-corrected cell line (BrS-corr) were differentiated into cardiomyocytes (hiPSC-CMs) for the study. Reductions of Nav 1.5 expression, peak sodium channel current (INa ) and upstroke velocity (Vmax ) of action potentials with an increase in arrhythmic events were detected in BrS compared to non-BrS and BrS-corr cells. Increasing the cell culture temperature from 37 to 40°C (fever-like state) exacerbated the phenotypic changes in BrS cells. The fever-effects were enhanced by protein kinase A (PKA) inhibitor but reversed by PKA activator. Lipopolysaccharides (LPS) but not increased temperature up to 40°C enhanced the autophagy level in BrS-hiPSC-CMs by increasing reactive oxidative species and inhibiting PI3K/AKT signalling, and hence exacerbated the phenotypic changes. LPS enhanced high temperature-related effect on peak INa shown in BrS hiPSC-CMs. Effects of LPS and high temperature were not detected in non-BrS cells. The study demonstrated that the SCN5A variant (c.3148G>A/p.Ala1050Thr) caused loss-of-function of sodium channels and increased the channel sensitivity to high temperature and LPS challenge in hiPSC-CMs from a BrS cell line with this variant but not in two non-BrS hiPSC-CM lines. The results suggest that LPS may exacerbate BrS phenotype via enhancing autophagy, whereas fever may exacerbate BrS phenotype via inhibiting PKA-signalling in BrS cardiomyocytes with but probably not limited to this variant.

Tolerability and Safety of Lacosamide in Neonatal Population.

Lacosamide is a newer antiepileptic medication used in refractory neonatal seizures with limited safety and efficacy data. This case series spans 4 years and includes 38 neonates cared for in the neonatal, pediatric, and cardiovascular intensive care units, who received lacosamide for refractory seizures. Because lacosamide affects atrioventricular node function in adults, among other metrics, electrocardiogram (ECG) changes were monitored closely in these neonates. Within this cohort, 2 neonates were found to have atrial bigeminy on ECG and telemetry. Otherwise, lacosamide was generally well tolerated with sleepiness being the most common symptom noted. This case series reports data on the tolerability of lacosamide and emphasizes the importance of monitoring key cardiac intervals with ECG before and after the use of lacosamide in this population.

QRS and QT Interval Modifications in Patients with Type 2 Diabetes Mellitus.

Diabetes Mellitus imbricates inflammatory processes on their pathophysiology, it could affect cardiac electrophysiology. Cardiac inflammatory process leads electrocardiogram changes. Nevertheless, there are discrepancies about whether it prolongs or decreases waves and intervals such as QRS and QT. Furthermore, QRS dispersion has not been studied. To identify QRS complex and QT interval modifications in type 2 diabetic patients. A descriptive cross-sectional study was carried out in 59 type 2 diabetic patients selected by non-probabilistic sampling. Electrocardiogram was performed, QRS and QT interval were measured manually by two observers. Dispersion of both variables was calculated to compare with normal values. Two variables showed differences for sex, QRS dispersion was higher in females (45.84), p=0.0001 vs. reference value; QT dispersion (63.12) showed significance difference (p=0.0246) vs. reference value for males. Greater than five years of illness was related to higher QRS values (124.11 vs. 137.28), p=0.005 and corrected QT dispersion (61.81 vs. 78.79), p=0.022. The electrocardiographic differences between sexes may suggest a gender influence. The longer duration of diabetes diseases could increase cardiovascular risk of arrhythmias due to greater QRS duration and corrected QT interval prolongation.

Isolated T wave Inversion in Lead aVL as an early sign of Inferior Wall Myocardial Infarction

Electrocardiogram (ECG) is instrumental in identifying acute myocardial infarction (AMI). ST-segment elevation in a region of specific coronary vessels in an acute coronary syndrome (ACS) setting is the hallmark of AMI. Reciprocal ST depression and T wave inversion (TWI) are well-recognized changes that could accompany ST segment elevations. Reciprocal changes may represent the only early manifestation of AMI and may be present in specific leads such as lead aVL as early and sensitive markers of AMI. Abnormalities in the ST segment and T wave can result from non-ACS causes, but early recognition and appropriate intervention are paramount for patients with ACS. We report a case of a 55-year-old male with acute IWMI with early reciprocal and dynamic ECG changes with a literature review.

Correlation of Mean Heart Dose and Cardiac Biomarkers with Electrocardiographic Changes in Patients Receiving Thoracic Radiation Therapy.

Cardiotoxicity is a well-recognized, serious adverse effect of thoracic radiation therapy. This study aimed to evaluate longitudinal electrocardiogram (ECG) changes in patients receiving thoracic radiation therapy and identify correlating factors that can predict the risk of cardiotoxicity. This retrospective study included 202 patients treated with thoracic radiation therapy, and chemotherapy and targeted therapy were allowed. Mean heart dose (MHD) was evaluated on dose-volume histograms. ECG, high-sensitivity cardiac troponin T (hs-cTnT), and N-terminal B-type natriuretic peptide (NT-proBNP) analyses were conducted before irradiation and during the follow-up period of 6-12 months (average 8 months). Chi square test and logistic regression analysis were applied to identify risk factors associated with ECG changes. At a median time of 3 months postirradiation, 46.5% of patients showed ECG changes, and 33.0% of patients achieved baseline ECG levels during the follow-up period at a median of 5 months postirradiation. Logistic regression analysis identified MHD, hs-cTnT and NT-pro BNP as significant factors associated with ECG changes (P < 0.05). Hs-cTnT and NT-proBNP were increased significantly after radiation therapy compared with baseline levels (P < 0.05), and these increases were observed as a median time of 2 months postirradiation, which was earlier than ECG changes. Higher MHD and elevated hs-cTnT and NT-proBNP levels correlated with an increased risk of ECG changes in patients receiving thoracic radiation therapy. Early identification of patients at high risk of cardiotoxicity and timely intervention might reduce the incidence of radiation-induced cardiac toxicity.

Ring finger protein 10 improves pirarubicin-induced cardiac inflammation by regulating the AP-1/Meox2 signaling pathway

ObjectivesPirarubicin (THP) is widely used in clinical antitumor therapy, but its cardiotoxicity seriously affects the therapeutic effect in patients. In the study, we investigated the role of ring finger protein 10 (RNF10) in cardiotoxicity induced by THP. Materials and methodsA cardiac toxicity model in Sprague-Dawley (SD) rats induced by THP was established. Changes in diet, weight, electrocardiogram (ECG), and echocardiography were observed. Serum levels of brain natriuretic peptide (BNP), creatine kinase MB (CK-MB), cardiac troponin T (cTnT), and lactate dehydrogenase (LDH) were measured. The expression of RNF10 in myocardium was observed by immunohistochemistry. The expressions of RNF10, activator protein-1 (AP-1), mesenchyme homeobox 2 (Meox2), total nuclear factor (NF)-κB p65 (T-P65), phosphorylated NF-κB p65 (PP65), monocyte chemoattractant protein-1 (MCP-1), tumor necrosis factor (TNF)-α, interleukin (IL)-6, and mature IL-1β were detected by Western blot. A THP-induced H9c2 myocardial cell injury model was established. RNF10 was downregulated or overexpressed by RNF10 siRNA and a RNF10 lentiviral vector, respectively. Then, cell viability was measured. The expression of RNF10 in H9c2 cells was observed by immunofluorescence. All of the above signaling pathways were verified by Western blots. FindingsTHP caused a series of cardiotoxic manifestations in SD rats. Our studies suggested that THP caused cardiac inflammation by inhibiting the expression of RNF10, while overexpression of RNF10 antagonized the cardiotoxicity induced by THP. SignificanceOur study showed RNF10 improved THP-induced cardiac inflammation by regulating the AP-1/Meox2 signaling pathway. RNF10 may be a new target to treat THP-induced cardiotoxicity.

Metformin and Dapagliflozin Attenuate Doxorubicin-Induced Acute Cardiotoxicity in Wistar Rats: An Electrocardiographic, Biochemical, and Histopathological Approach

Doxorubicin is a widely used anticancer drug whose efficacy is limited due to its cardiotoxicity. There is no ideal cardioprotection available against doxorubicin-induced cardiotoxicity. This study aimed to investigate the anticipated cardioprotective potential of metformin and dapagliflozin against doxorubicin-induced acute cardiotoxicity in Wistar rats. At the beginning of the experiment, cardiac screening of experimental animals was done by recording an electrocardiogram (ECG) before allocating them into the groups. Thereafter, a total of thirty healthy adult Wistar rats (150–200 g) were randomly divided into five groups (n = 6) and treated for eight days as follows: group I (normal control), group II (doxorubicin control), group III (metformin 250 mg/kg/day), group IV (metformin 180 mg/kg/day), and group V (dapagliflozin 0.9 mg/kg/day). On the 7th day of the treatment phase, doxorubicin 20 mg/kg was administered intraperitoneal to groups II, III, IV, and V. On the 9th day (immediately after 48 h of doxorubicin administration), blood was collected from anesthetized animals for glucose, lipid profile, CK-MB & AST estimation, and ECG was recorded. Later, animals were sacrificed, and the heart was dissected for histopathological examination. We found that compared to normal control rats, CK-MB, AST, and glucose were significantly increased in doxorubicin control rats. There was a significant reversal of doxorubicin-induced hyperglycemia in the rats treated with metformin 250 mg/kg compared to doxorubicin control rats. Both metformin (180 mg/kg and 250 mg/kg) and dapagliflozin (0.9 mg/kg) significantly altered doxorubicin-induced ECG changes and reduced the levels of cardiac injury biomarkers CK-MB and AST compared to doxorubicin control rats. Metformin and dapagliflozin protected the cellular architecture of the myocardium from doxorubicin-induced myocardial injury. Current study revealed that both metformin and dapagliflozin at the FDA-recommended antidiabetic doses mitigated doxorubicin-induced acute cardiotoxicity in Wistar rats. The obtained data have opened the perspective to perform chronic studies and then to clinical studies to precisely consider metformin and dapagliflozin as potential chemoprotection in the combination of chemotherapy with doxorubicin to limit its cardiotoxicity, especially in patients with comorbid conditions like type II diabetes mellitus.

A randomized, single-blind, multi-center clinical observational study of a new super lubricath coating catheter latex catheters using in urethral catheterization

ABSTRACT Polymer polyvinylpyrrolidone (PVP) can be described as the main coating. After heating and curing, it is able to build a strong adhesion to the latex catheter for creating a durable and effective hydrophilic coating. In this study, we aim to explore the advantages and disadvantages of the new super lubricath latex catheter PVP coating compared with the common latex catheter. 148 patients who participated in the study were completely randomly divided into two groups, the observation group and the control group. When the urinary catheter was incubated, indwelling in subjects’ body, and removed from the subjects, the researchers accordingly recorded the subjects’ comfort feedback, device safety evaluation and the patient’s vital signs, relevant blood and urine examination index, electrocardiogram (ECG) changes and recorded various adverse events. PVP super lubricath coating latex catheter offered better comfort, less damage to the urethra, and no significant disadvantage in safety compared to regular latex catheters, improving quality of care and patient satisfaction compared to regular latex urinary catheters.

Conflicting results on the role of ECG in risk-stratification for sudden cardiac death in childhood hypertrophic cardiomyopathy.

The research group at University College London introduced the concept of standardizing the quantification of risk by assessing risk of sudden death or equivalent malignant arrhythmia event occurring during the subsequent 5 years of follow-up after diagnosis. While the aims in the recent article by Norrish et al.1 published in this journal are laudable, it is imperative to highlight the methodological shortcomings underlying their analysis. The authors aim to assess the ability of the electrocardiogram (ECG) risk-score and other aspects of the 12-lead ECG to predict ‘major arrhythmic cardiac event’. They selected a subset (356/1029) of the multi-centre cohort of paediatric patients with hypertrophic cardiomyopathy (HCM) used to construct the HCM Risk-Kids algorithm, where ECGs had been archived. This subset however consisted mainly of recently recruited patients, and so median follow-up was only 3.9 years (interquartile range Q1–Q3 2.0–7.7).1 A major concern is that Norrish et al. did not restrict their analysis to include only those survivors who had reached 5 years of follow-up (n = 77 + 68 = 145), and the patients who had a ‘major arrhythmic cardiac event’ within 5 years of follow-up (n = 17). Instead they compared all patients without events, even if 25% of them had <2 years follow-up, with all patients who had major arrhythmic cardiac event, even if 8 of them had an event later than 5 years of follow-up. Thus, in fact, only 17 (patients with major arrhythmic cardiac event within 5 years) + 145 (patients with ≥5 years follow-up without event) = 162 of the patients are actually statistically informative about the end-point of major arrhythmic cardiac event within 5 years.1 This constitutes only 46% of the total ECG group analysed. The other 194 actually confuse the results as patients with high-risk ECG features and short follow-up might have had a major arrhythmic cardiac event later on within the 5-year span. Similarly, the ECGs of patients with major arrhythmic cardiac event after >5 years of follow-up might have evolved more ECG changes closer to the event as shown in other studies.2 Thus including these late major arrhythmic cardiac events will underestimate the sensitivity of the method.

An Observational Study of Vataja Hridroga in Correlation with Electrocardiographic Changes

Diagnosing a disease is far important before initiating the treatment. Different important and involuntary functions are regulated by different Dosha, Dhatu and Oja, which are situated in the heart. Hridroga is disease of Marma and is life threatening. However emphasis is given to explore the possibility of inclusion of electrocardiogram a bedside investigating tool as a support to existing Pramanas and Rugna pariksha. In accordance with the World Health Organization, India accounts for one-fifth of these deaths worldwide especially in younger population. So the study aimed at comprehension of electrocardiographic changes in patients suffering from Vataja Hridroga as mentioned in Charak samhita, Sushruta Samhita, Ashtanghridaya and their specific correlation. 100 patients were included in the study and their symptomatology with electrocardiographic changes was observed. Vata Pradhan Kapha-Pitta Anubandha observed in in 38% patients, Vata Pradhan Kapha Anubandha observed in 34% patients, Keval Vata Pradhanata observed in 23% patients, Vata Pradhan Pitta Anubandha observed in 5% patients. This Kapha-Pitta Anubandha indicates its contribution in Srotorodha Pradhan and Avaranatmak Samprapti. Dosha vitiation and Anubandha causes various pathological changes in Hridaya like Shotha, Paka, Srotorodh thereby leads to specific changes in electrocardiogram. Significant correlation between two were observed.

A Study of Cardiovascular Manifestations in Hypothyroidism

Aim and Objective: To study cardiovascular manifestations in hypothyroidism. Materials and Methods: An observational study was carried out in Parul Sevashram Hospital, Vadodara, Gujarat, India. 150 patients, both men, and women, diagnosed with hypothyroidism attending the Parul Sevashram Hospital were recruited from the outpatient and in-patient departments of medicine. Clinical profiles, history, complications, and all required data were collected. All patients were regularly called for follow-up based on their visits. As per the investigator’s discretion, laboratory tests, i.e., thyroid function tests, CBC, electrocardiogram (ECG), and 2D echocardiography were performed as and when required, and medication was prescribed. All physical examinations and all vitals were recorded at every visit till the end of the study. Results: A total of 150 patients were included in this study. Male:female: 57:93; age: 28–76 years. Patients were examined in a prospective manner and results were compared with the control group to evaluate the effect of hypothyroidism, subclinical and overt, on the cardiac status by echocardiography. Variables of heart structure and function were assessed by cross-sectional and Doppler echocardiography. Interventricular septum (IVS) dimensions were significantly raised in moderate subclinical and severe overt hypothyroidism (mean 0.9 +/- 0.03 and 0.9 +/- 0.2 cm). Left ventricular posterior wall (LVPW) thickness was significantly increased only in overt hypothyroidism (mean 1.3 +/- 0.2). However, RVW and LVID showed no definite pattern of change. Pericardial effusion and diastolic dysfunction were seen in 72 cases only in overt hypothyroidism. Diastolic dysfunction with pericardial effusion was found in 74 (49.3%) cases followed by diastolic dysfunction in 49 (32.6%), systolic dysfunction in 15 (10.0 %), and increased interventricular septum spectrum thickness in 12 (8.6%) patients. The majority of the diastolic dysfunction was mild dysfunction associated with females. No cases were found to have severe diastolic dysfunction. Discussion: On the basis of a case history, the clinical and para-clinical manifestations of hypothyroidism are reviewed. Exertion dyspnea without signs of cardiac insufficiency occurs frequently. The minute and stroke volume and heart rate are reduced. The blood pressure may rise (reversible) and hypertension may occur. The function of the left ventricle is reversibly reduced. X-ray of the thorax may reveal massive relatively asymptomatic pleural effusion and cardiomegaly. Pericardial exudate occurs frequently and is demonstrated best by echocardiography. The plasma concentrations of several different enzymes (including creatine kinase (CK), CK-MB, and LDH) may be raised in myxedema. The reason for this is perhaps compromised membrane function in the skeletal muscle cells. Conclusion: Hypothyroidism, both subclinical and overt, is associated with cardiovascular alteration, both structural and functional. IVS and LVPW thickness are markedly affected, and there is an impairment in left ventricular function in diastole. Furthermore, hypothyroidism is more common in females, between the age group of 20–50 years. The majority of the patients have cardiovascular changes such as ECG abnormalities, pericardial effusion, diastolic dysfunction, and diastolic hypertension. We strongly suggest early detection and initiation of hormone replacement therapy can minimize the associated cardiovascular changes. Recommendation: To study inter-and intracellular deposits, infiltrations, and fibrosis in the myocardium and these probably contribute to some of the on-specific, reversible ECG changes (low voltage, flattening/inversion of T waves, sinus bradycardia). To study hypothyroidism present can increase atheroma formation. The patients can be grouped into overt and subclinical hypothyroid.

Non-invasive detection of cardiac allograft rejection among heart transplant recipients using an electrocardiogram based deep learning model.

Current non-invasive screening methods for cardiac allograft rejection have shown limited discrimination and are yet to be broadly integrated into heart transplant care. Given electrocardiogram (ECG) changes have been reported with severe cardiac allograft rejection, this study aimed to develop a deep-learning model, a form of artificial intelligence, to detect allograft rejection using the 12-lead ECG (AI-ECG). Heart transplant recipients were identified across three Mayo Clinic sites between 1998 and 2021. Twelve-lead digital ECG data and endomyocardial biopsy results were extracted from medical records. Allograft rejection was defined as moderate or severe acute cellular rejection (ACR) based on International Society for Heart and Lung Transplantation guidelines. The extracted data (7590 unique ECG-biopsy pairs, belonging to 1427 patients) was partitioned into training (80%), validation (10%), and test sets (10%) such that each patient was included in only one partition. Model performance metrics were based on the test set (n = 140 patients; 758 ECG-biopsy pairs). The AI-ECG detected ACR with an area under the receiver operating curve (AUC) of 0.84 [95% confidence interval (CI): 0.78-0.90] and 95% (19/20; 95% CI: 75-100%) sensitivity. A prospective proof-of-concept screening study (n = 56; 97 ECG-biopsy pairs) showed the AI-ECG detected ACR with AUC = 0.78 (95% CI: 0.61-0.96) and 100% (2/2; 95% CI: 16-100%) sensitivity. An AI-ECG model is effective for detection of moderate-to-severe ACR in heart transplant recipients. Our findings could improve transplant care by providing a rapid, non-invasive, and potentially remote screening option for cardiac allograft function.

Reversible QRS attenuation/fragmentation in patients with takotsubo syndrome.

To the Editor: I read with great interest the paper by Li et al,1 about the 80-year-old woman whose electrocardiogram (ECG), in the setting of takotsubo syndrome (TTS), revealed “fragmentation of the QRS complexes across precordial leads V4-6, lead aVR, and a positive deflection embedded within the QRS complex in lead V1.” The comprehensive analysis of the authors about the pathogenesis of arrhythmias in patients with TTS, in connection with the vagal influences, and underlying myocardial edema and microfibrosis, are highly appreciated. I have some comments and questions for the authors: (1) In reference to the statement that these ECG changes were resolved in 3 months, it will be of interest to the readers to know whether other ECGs in this patient were recorded between the admission and the 3-month time point, and if such ECGs revealed QRS fragmentation or its earlier resolution. (2) Reversible attenuation of the QRS amplitude has been previously described in various combinations of the ECG leads, and lead aVR, in connection with TTS, and attributed to myocardial edema2, 3; careful inspection of Figure 1 of the present paper reveals attenuation of the QRS amplitude in leads I, II, III, aVR, aVL, aVF, V1, and V3–V6. (3) Did the patient have any ECGs prior to her admission with TTS, to compare it with the ECG obtained on admission? None.

Longitudinal association of electrocardiogram abnormalities with major adverse cardiac events in people with Type 2 diabetes: the Hoorn Diabetes Care System cohort.

To investigate the association of (changes in) electrocardiogram (ECG) abnormalities with incident major adverse cardiac events (MACE) in people with Type 2 diabetes (T2D) without pre-existing cardiovascular disease (CVD). A prospective longitudinal study of 11 993 people with T2D without known CVD from the Hoorn Diabetes Care System cohort. Annually repeated measurements (1998-2018), included cardiovascular risk factors, over 70 000 ECG, and self-reported cardiovascular events. ECG abnormalities were classified according to the Minnesota Classification as prolonged PR duration, prolonged QRS duration, left QRS-axis, QS pattern, ST-segment/T-wave abnormalities, or tall R-wave. The association of ECG abnormalities with MACEs was assessed using time-dependent Cox-regression models, adjusted for time-varying cardiovascular risk factors, and medication use [hazard ratios (HRs) with 95% confidence intervals (CIs)]. During a median follow-up of 6.6 (IQR, 3.1-10.7) years, 5445 (45.4%) of the participants had an ECG abnormality (prevalent or incident) at any of the median 6 (IQR, 3-10) annual ECG recordings, and 905 people (7.5%) had a MACE (529 coronary heart disease (CHD), 250 heart failure (HF), and 126 sudden cardiac arrest (SCA)). After adjustment, most ECG abnormalities were associated with HF: prolonged QRS duration [HR, 4.01 (95% CI, 2.67-6.03)], QS pattern [2.68 (0.85-8.49)], ST-segment/T-wave abnormalities [4.26 (2.67-6.80)], and tall R-wave [2.23 (1.33-3.76)]. Only QS pattern [2.69 (1.20-6.03)] and ST-segment/T-wave abnormalities [2.11 (1.48-3.02)] were associated with CHD. These associations were robust across age, sex, hypertension, or estimated CVD risk subgroups. In people with T2D without pre-existing CVD, ECG abnormalities related to decelerated conduction, ischaemia, and hypertrophy are predominantly early signs of emerging HF, while only abnormalities related to ischaemic disorders are signs of CHD.

Changes of electrocardiograms and heart morphology of animals with different resistance to hypoxia under influences of stress

Stress is a process that increases a person’s adaptive capacity and leads to the various diseases, such as hypertension, coronary artery disease, heart attack, cardiac arrest, stroke, mental disorders such as depression and anxiety and even sudden death. Individual response to stress may depend on age, gender, features of autonomic regulation, state of the central nervous system, endocrine systems, higher nervous activity. With excessive stress, the work of internal organs is disturbed, in particular, the cardiovascular system. Determination of the damaging effect of stress on the cardiovascular system in individuals with different reactivity will contribute to the development of individual correction methods. The aim of the study was to analyze the changes in electrocardiograms (ECG) and morphological feachers after stress in animals with different resistance to hypoxia. Material and methods of investigation. Experiments were performed on 48 Wistar rats, with high and low resistance to hypoxia (HRH, LRH), aged 5–6 months. Animals were divided into two groups – control and experimental (after immobilization stress). Individuals with different resistance to hypoxia were selected by method of V. Ya. Berezovsky. Stress was modeled by three one-hour immobilization of rats, which were immobilized on their backs with an interval of 24 hours between each stressful episode. Investigation we did after 24 hours after third immobilization. Under anesthesia were registrated ECG and taken heart for morphological investigation. Sections were stained with hematoxylin and eosin. Results. In examining the ECG in control HRH and LRH animals, no significant difference in the analyzed ECG indicators was established. 24 hours after the last 1 hour three-time immobilization in HRH rats were noted an increase in heart rate, a decrease of the duration of the RR interval, a decrease of the amplitude of the R wave, an increase of QTc interval, an increase of the amplitude of the T wave, an increase in the deviation of the ST segment from the isoline. In LRH rats, stress caused an increase in heart rate, a decrease in the duration of the RR interval, a decrease in the duration of the PQ interval, a decrease in the amplitude of the R wave, an increase in the amplitude of the T wave, an increase in the deviation of the ST segment from the isoline. When comparing the parameters of НRH and LRH rats, in LRH were found a smaller amplitude of the P wave, a smaller amplitude of the R wave, a smaller value of the QTc interval, greater deviation of the ST segment from the isoline. Physiological changes on ECG can also connected with morphological feaches. Conclusions. Stress leads to changes in functional and histological properties of heart, which depends on resistance to hypoxia. In the ECG 24 hours after the last 1 hour three-time immobilization in HRH and LRH rats were noted an increase in heart rate, a decrease of the duration of the RR interval, a decrease of the amplitude of the R wave, an increase of the amplitude of the T wave, an increase in the deviation of the ST segment from the isoline. In HRH rats were also an increase of QTc interval, in LRH rats – a decrease in the duration of the PQ interval. Indxes changes were grater in LRH rats. Mophological changes was higher also in LRH animals.