Ecg

This paper presents a review of the techniques found in the literature that aim to achieve a robust heartbeat detection from fusing multi-modal physiological signals (e.g., electrocardiogram (ECG), blood pressure (BP), artificial blood pressure (ABP), stroke volume (SV), photoplethysmogram (PPG), electroencephalogram (EEG), electromyogram (EMG), and electrooculogram (EOG), among others). Techniques typically employ ECG, BP, and ABP, of which usage has been shown to obtain the best performance under challenging conditions...

Ambulatory electrocardiography (ECG) allows for extended monitoring of arrhythmias in a real-world setting. This article reviews the currently available ambulatory ECG devices and their differences in design, function, indications, efficacy, cost, and optimal use in clinical practice.

An autopsy case of sudden death due to pulmonary arterial hypertension (PAH) in a 5-year-old boy whose cause of death was not determined during autopsy, but was later determined by postmortem examination, is presented. The boy developed convulsions that subsequently stopped, but remained unconscious. He was transported to hospital by ambulance, but died soon after. The boy had been found to have right ventricular overload on ECG 2 weeks earlier. A plan had been made to consult a doctor for a specialist visit 2 months later...

AIMS: Patients with left ventricular dysfunction (LVD) and prolonged QRS on surface electrocardiogram are at increased risk for heart failure and death and may benefit from resynchronization therapy. Patients with initial narrow QRS may prolong their QRS during the disease course. The occurrence of delayed QRS prolongation, its predictors and associated risk of heart failure hospitalizations (HFH) or death are currently unknown and the subject of this investigation. METHODS & RESULTS: Patients with LVD, QRS < 120 ms and available follow-up ECGs were retrospectively evaluated for persistent unprovoked QRS prolongation >130 ms...

This paper deals with transformations from electrocardiographic (ECG) to vectorcardiographic (VCG) leads. VCG provides better sensitivity, for example for the detection of myocardial infarction, ischemia, and hypertrophy. However, in clinical practice, measurement of VCG is not usually used because it requires additional electrodes placed on the patient's body. Instead, mathematical transformations are used for deriving VCG from 12-leads ECG. In this work, Kors quasi-orthogonal transformation, inverse Dower transformation, Kors regression transformation, and linear regression-based transformations for deriving P wave (PLSV) and QRS complex (QLSV) are implemented and compared...

OBJECTIVES: To evaluate emergency medical services (EMS) delays and their impact on time to treatment and mortality in patients with ST-elevation myocardial infarction (STEMI). METHOD: We collected data on EMS time intervals from published studies across five electronic databases. The primary EMS interval was the time in minutes between first medical contact and arrival at hospital door (FMC-to-door time). Secondary intervals were other components of EMS delay. Weighted means were measured using random-effects models...

BACKGROUND: There is limited data on electrocardiographic (ECG) abnormalities and their prognostic significance in women with peripartum cardiomyopathy (PPCM). We sought to characterize ECG findings in PPCM and explore the association of ECG findings with myocardial recovery and clinical outcomes. HYPOTHESIS: We hypothesized that ECG indicators of myocardial remodeling would portend worse systolic function and outcomes. METHODS: Standard 12-lead ECGs were obtained at enrollment in the Investigations of Pregnancy-Associated Cardiomyopathy study and analyzed for 88 women...

BACKGROUND: Prior studies have proposed several electrocardiogram (ECG) criteria in limb leads for identifying the culprit coronary artery (CCA) in patients with acute inferior wall myocardial infarction (IWMI). The aim of our study was to conduct an evidence-based evaluation and test accuracy comparison of these criteria. METHODS: We searched the PubMed, Embase, and Ovid. Eligible studies to assess the diagnostic performance of ECG criteria predicting CCA in IWMI were reviewed for inclusion...

Implantable loop recorder with discontinuous ECG recording enables monitoring of heart rhythm over several years. Consequently, in patients with recurrent syncope it is possible to record an ECG during the next syncopal event to obtain symptom-ECG correlations. In patients with recurrent syncope of unknown origin, the implantation of a loop recorder leads to an earlier diagnosis and an asystole is more often detected as the cause of the recurrent syncope. In addition, the loop recorder identifies patients who will benefit from pacemaker implantation...

Our contribution focuses on the characterization of sleep apnea from a cardiac rate point of view, using Recurrence Quantification Analysis (RQA), based on a Heart Rate Variability (HRV) feature selection process. Three parameters are crucial in RQA: those related to the embedding process (dimension and delay) and the threshold distance. There are no overall accepted parameters for the study of HRV using RQA in sleep apnea. We focus on finding an overall acceptable combination, sweeping a range of values for each of them simultaneously...

BACKGROUND: Using a comprehensive ST-segment-elevation myocardial infarction registry, we evaluated the relationships of baseline Q waves, time from symptom onset, and reperfusion strategy with in-hospital clinical outcomes. METHODS AND RESULTS: Consecutive ST-segment-elevation myocardial infarction patients from a defined health region were classified by the presence of baseline Q waves and additionally into primary percutaneous coronary intervention, fibrinolysis, or no reperfusion...

BACKGROUND: Pulmonary embolism (PE) represents a clinical challenge for clinicians because of nonspecific presentations, including dyspnea, chest pain, and tachycardia. The immediate 12-lead electrocardiogram (ECG) is commonly used to facilitate differential diagnosis of acute chest pain. Although relative rare, massive pulmonary embolism could induce ST segment elevation and mimic acute myocardial infarction. CASE PRESENTATION: We present a challenging scenario that ECG showed ST segment elevation, nevertheless, urgent coronary angiogram revealed non-obstructive coronary artery disease...

BACKGROUND: Terminal "QRS distortion" on the electrocardiogram (ECG) (based on Sclarovsky-Birnbaum's Grades of Ischemia Score) is a sign of severe ischemia, associated with adverse cardiovascular outcome in ST-segment elevation myocardial infarction (STEMI). In addition, ECG indices of the acuteness of ischemia (based on Anderson-Wilkins Acuteness Score) indicate myocardial salvage potential. We assessed whether severe ischemia with or without acute ischemia is predictive of infarct size (IS), myocardial salvage index (MSI) and left ventricular ejection fraction (LVEF) in anterior versus inferior infarct locations...

BACKGROUND: Delays in attending to ST-elevation myocardial infarction (STEMI) are indicators or markers of quality of health services. Several records suggest gender disparity in cardiac care as a contributor to the increased mortality among women. METHODS: We prospectively enrolled all consecutive STEMI patients who were transferred to our hospital from January through December 2015. The following variables were analyzed: Symptom-to-Door Time (SDT); Time to First ECG (TECG); Transfer Time to Referring Center (TTRC); and Door-to-Cath lab time (DCT)...

Importance: Severe heart failure caused by cardiac sarcoidosis is difficult to diagnosis without biopsy. Objective: To assess whether total electrocardiographic 12-lead QRS voltage may be a clue to diagnosis. Design, Setting, Participants: Case-series study with cases collected at Baylor University Medical Center at Dallas, Dallas, Texas, from January 13, 2005, to January 24, 2017. The clinical records of 16 patients with severe heart failure caused by cardiac sarcoidosis were studied...

Importance: Clinical guidelines advise against routine electrocardiograms (ECG) in low-risk, asymptomatic patients, but the frequency and impact of such ECGs are unknown. Objective: To assess the frequency of ECGs following an annual health examination (AHE) with a primary care physician among patients with no known cardiac conditions or risk factors, to explore factors predictive of receiving an ECG in this clinical scenario, and to compare downstream cardiac testing and clinical outcomes in low-risk patients who did and did not receive an ECG after their AHE...

A resting electrocardiogram (ECG) is recommended for screening of sudden cardiac death in young athletes. However, ECG interpretation in athletes requires an adequate training because normal physiological training adaptations in athletes can sometimes be hardly distinguished from abnormal findings suggestive of underlying pathology. In 2017, a consensus of international experts established new recommendations for a clear and accurate interpretation of ECGs in athletes. This article aims to guide non-cardiologists according to these new data, allowing a better triage of anomalies requiring further investigations...

BACKGROUND: Interpretation of the athlete's ECG is based on differentiation between benign ECG changes and potentially pathological abnormalities. The aim of the study was to compare the 2010 European Society of Cardiology (ESC) and the 2017 International criteria for differential diagnosis between hypertrophic cardiomyopathy (HCM) and athlete's heart. METHODS: The study populations included 200 patients with HCM and 563 athletes grouped as follows: 'group 1', including normal ECG and isolated increase of QRS voltages, which are considered non-pathologic according to ESC and International criteria; 'group 2', including left atrial enlargement or left axis deviation in isolation and Q-waves with an amplitude ≥4 mm but <25% of the ensuing R-wave and a duration <0...

PURPOSE: Cardiac late effects are responsible for a significant burden of mortality and morbidity among pediatric Hodgkin's lymphoma (HL) survivors (HLS). The aim of our study was to assess clinical and subclinical cardiac sequelae in a cohort of childhood HLS treated in the 1980s with doxorubicin, bleomycin, vinblastine, and dacarbazine (the ABVD regimen) and limited-field radiotherapy (RT). METHODS: We retrospectively examined a series of HLS treated from 1979 to 1989...

PURPOSE: Athletes and members of the public increasingly rely on wearable HR monitors to guide physical activity and training. The accuracy of newer, optically based monitors is unconfirmed. We sought to assess the accuracy of five optically based HR monitors during various types of aerobic exercise. METHODS: Fifty healthy adult volunteers (mean ± SD age = 38 ± 12 yr, 54% female) completed exercise protocols on a treadmill, a stationary bicycle, and an elliptical trainer (±arm movement)...