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Qiu S, Liu T, Zhan Z, Li X, Liu X, Xin X, Lu J, Wu L, Wang L, Cui K, Xiu J. Revisiting the diagnostic and prognostic significance of high-frequency QRS analysis in cardiovascular diseases: a comprehensive review. Postgrad Med J 2024:qgae064. [PMID: 38796714 DOI: 10.1093/postmj/qgae064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2024] [Revised: 04/07/2024] [Accepted: 04/19/2024] [Indexed: 05/28/2024]
Abstract
Cardiovascular diseases (CVDs) present a significant global public health threat, contributing to a substantial number of cases involving morbidity and mortality. Therefore, the early and accurate detection of CVDs plays an indispensable role in enhancing patient outcomes. Decades of extensive research on electrocardiography at high frequencies have yielded a wealth of knowledge regarding alterations in the QRS complex during myocardial ischemia, as well as the methodologies to assess and quantify these changes. In recent years, the analysis of high-frequency QRS (HF-QRS) components has emerged as a promising non-invasive approach for diagnosing various cardiovascular conditions. Alterations in HF-QRS amplitude and morphology have demonstrated remarkable sensitivity as diagnostic indicators for myocardial ischemia, often surpassing measures of ST-T segment changes. This comprehensive review aims to provide an intricate overview of the current advancements, challenges, and prospects associated with HF-QRS analysis in the field of CVDs.
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Affiliation(s)
- Shifeng Qiu
- Department of Cardiology, Southern Medical University, Nanfang Hospital, Guangzhou 510515, China
- Guangdong Provincial Key Laboratory of Shock and Microcirculation, Southern Medical University, Nanfang Hospital, Guangzhou 510515, China
- State Key Laboratory of Organ Failure Research, Southern Medical University, Nanfang Hospital, Guangzhou 510515, China
| | - Tinghui Liu
- Department of Cardiology, Southern Medical University, Nanfang Hospital Zengcheng Campus, Guangzhou 511340, China
| | - Zijin Zhan
- Department of Cardiology, Southern Medical University, Nanfang Hospital Zengcheng Campus, Guangzhou 511340, China
| | - Xue Li
- Department of Gastroenterology, Southern Medical University, Nanfang Hospital, Guangzhou 510515, China
| | - Xuewei Liu
- Guangdong Provincial Key Laboratory of Shock and Microcirculation, Southern Medical University, Nanfang Hospital, Guangzhou 510515, China
- The Tenth Affiliated Hospital of Southern Medical University (Dongguan People's Hospital), Southern Medical University or The First School of Clinical Medicine, Southern Medical University, Dongguan 523018, China
| | - Xiaoyu Xin
- Department of Cardiology, Southern Medical University, Nanfang Hospital, Guangzhou 510515, China
- Guangdong Provincial Key Laboratory of Shock and Microcirculation, Southern Medical University, Nanfang Hospital, Guangzhou 510515, China
- State Key Laboratory of Organ Failure Research, Southern Medical University, Nanfang Hospital, Guangzhou 510515, China
| | - Junyan Lu
- Department of Cardiology, Southern Medical University, Nanfang Hospital, Guangzhou 510515, China
- Guangdong Provincial Key Laboratory of Shock and Microcirculation, Southern Medical University, Nanfang Hospital, Guangzhou 510515, China
- State Key Laboratory of Organ Failure Research, Southern Medical University, Nanfang Hospital, Guangzhou 510515, China
| | - Lipei Wu
- Department of Cardiology, Southern Medical University, Nanfang Hospital Zengcheng Campus, Guangzhou 511340, China
| | - Li Wang
- Department of General Internal Medicine Unit One, Southern Medical University, Nanfang Hospital Zengcheng Campus, Guangzhou 511340, China
| | - Kai Cui
- Department of Cardiology, Southern Medical University, Nanfang Hospital, Guangzhou 510515, China
- Guangdong Provincial Key Laboratory of Shock and Microcirculation, Southern Medical University, Nanfang Hospital, Guangzhou 510515, China
- State Key Laboratory of Organ Failure Research, Southern Medical University, Nanfang Hospital, Guangzhou 510515, China
| | - Jiancheng Xiu
- Department of Cardiology, Southern Medical University, Nanfang Hospital, Guangzhou 510515, China
- Guangdong Provincial Key Laboratory of Shock and Microcirculation, Southern Medical University, Nanfang Hospital, Guangzhou 510515, China
- State Key Laboratory of Organ Failure Research, Southern Medical University, Nanfang Hospital, Guangzhou 510515, China
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Liu L, Du X, Wei X, Dong W, Lu H, Jiang G, Deng G. The combination of high-frequency QRS and ST-segment alterations during exercise stress tests enhanced the diagnostic efficacy for coronary artery disease. Clin Cardiol 2024; 47:e24254. [PMID: 38476105 DOI: 10.1002/clc.24254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Revised: 02/28/2024] [Accepted: 03/01/2024] [Indexed: 03/14/2024] Open
Abstract
BACKGROUND High-frequency QRS (HF-QRS) manifests as a novel adjunct electrocardiographic marker with potential utility in coronary artery disease (CAD) detection. HYPOTHESIS We hypothesize that HF-QRS analysis may be superior to conventional ST-segment analysis in detecting CAD, and the combination of these two analyses in the exercise stress test may enhance the diagnostic efficacy for CAD. METHODS The study incorporated a sample of 157 patients (mean age 62 ± $\pm $ 9 years) referred for nonemergent angiography. Before angiography, patients underwent exercise stress testing utilizing an upright bicycle. High-resolution electrocardiogram (ECG) data were collected during the exercise test, facilitating both HF-QRS and conventional ST-segment analyses. The diagnostic efficacy of HF-QRS and ST-segment analysis were compared, utilizing angiographic outcomes as the gold standard. The study design integrated HF-QRS analysis and ST-segment analysis via sequential and concurrent testing protocols. RESULTS In terms of CAD detection, HF-QRS analysis displayed superior sensitivity compared to conventional ST-segment analysis (63% vs. 37%, p = .002). The serial test significantly increased specificity from 79% to 97% (p = .002) compared to ST-deviation analysis alone. It showed a markedly low sensitivity of 26%. The parallel test significantly increased sensitivity from 37% to 77% (p < .001), while retaining a moderate level of specificity of 51%. The quantity of ECG leads exhibiting a positive HF-QRS response demonstrated a correlation with the severity of CAD (p < .001). CONCLUSIONS HF-QRS analysis exhibited superior sensitivity in detecting angiographically confirmed CAD relative to conventional ST-segment analysis. Moreover, the combination of HF-QRS and ST-segment alterations during exercise stress test enhanced the diagnostic efficacy for CAD.
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Affiliation(s)
- Long Liu
- The First Clinical College, Chongqing Medical University, Chongqing, China
| | - Xinyue Du
- Cardiovascular Medicine Department, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Xue Wei
- The First Clinical College, Chongqing Medical University, Chongqing, China
| | - Wei Dong
- School of Medical Imaging, Zunyi Medical University, Zunyi, Guizhou, China
| | - Hong Lu
- The First Clinical College, Chongqing Medical University, Chongqing, China
| | - Guishen Jiang
- The First Clinical College, Chongqing Medical University, Chongqing, China
| | - Guolan Deng
- Cardiovascular Medicine Department, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
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Omer N, Bergman E, Ben-David T, Huri S, Beker A, Abboud S, Granot Y, Meerkin D. Changes in High-Frequency Intracardiac Electrogram Indicate Cardiac Ischemia. J Cardiovasc Transl Res 2021; 15:84-94. [PMID: 34115322 DOI: 10.1007/s12265-021-10146-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Accepted: 06/02/2021] [Indexed: 11/30/2022]
Abstract
High-frequency QRS (HFQRS) analysis of surface ECG is a reliable marker of cardiac ischemia (CI). This study aimed to assess the response of HFQRS signals from standard intracardiac electrodes (iHFQRS) to CI in swine and compare them with conventional ST-segment deviations. Devices with three intracardiac leads were implanted in three swine in a controlled environment. CI was induced by inflating a balloon in epicardial coronary arteries. A designated signal-processing algorithm was applied to quantify the iHFQRS content before, during, and after each occlusion. iHFQRS time responses were compared to conventional ST-segment deviations. Thirty-three over thirty-nine (85%) of the occlusions presented significant reduction in the iHFQRS signal, preceding ST-segment change, being the only indicator of CI in brief occlusions. iHFQRS was found to be an early indicator for the onset of CI and demonstrated superior sensitivity to conventional ST-segment deviations during brief ischemic episodes.
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Affiliation(s)
- Noam Omer
- The Department of Biomedical Engineering, Tel Aviv University, Tel Aviv, Israel.
| | | | | | | | | | - Shimon Abboud
- The Department of Biomedical Engineering, Tel Aviv University, Tel Aviv, Israel
| | | | - David Meerkin
- Department of Cardiology, Shaare Zedek Medical Center, Jerusalem, Israel
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Thomas GS, Ghashghaei R. An opportunity to improve exercise test accuracy by incorporating high frequency QRS (HFQRS) waveform assessment. J Nucl Cardiol 2020; 27:2076-2079. [PMID: 30693429 DOI: 10.1007/s12350-019-01600-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Accepted: 01/04/2019] [Indexed: 11/29/2022]
Affiliation(s)
- Gregory S Thomas
- MemorialCare Heart & Vascular Institute, Southern California, CA, USA.
- Division of Cardiology, University of California, Irvine School of Medicine, Orange, CA, USA.
| | - Roxana Ghashghaei
- MemorialCare Heart & Vascular Institute, Southern California, CA, USA
- Division of Cardiology, University of California, Irvine School of Medicine, Orange, CA, USA
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Balfour PC, Gonzalez JA, Shaw PW, Caminero MP, Holland EM, Melson JW, Sobczak M, Izarnotegui V, Watson DD, Beller GA, Bourque JM. High-frequency QRS analysis to supplement ST evaluation in exercise stress electrocardiography: Incremental diagnostic accuracy and net reclassification. J Nucl Cardiol 2020; 27:2063-2075. [PMID: 30506155 PMCID: PMC6542725 DOI: 10.1007/s12350-018-01530-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2018] [Accepted: 11/02/2018] [Indexed: 11/29/2022]
Abstract
BACKGROUND Exercise stress electrocardiography (ECG) alone is underutilized in part due to poor diagnostic accuracy. High-frequency QRS analysis (HF-QRS) is a novel tool to supplement ST evaluation during stress ECG. We compared the diagnostic accuracy and net reclassification of HF-QRS analysis compared with ST evaluation for substantial myocardial ischemia by exercise SPECT myocardial perfusion imaging (MPI). METHODS AND RESULTS Exercise SPECT MPI was performed in 257 consecutive eligible patients (mean age 59 ± 12, 67% male). An ischemic HF-QRS pattern was defined as a ≥ 1 µV absolute reduction and a ≥ 50% relative reduction of the root-mean-square of the 150-250 Hz band signal in ≥ 3 leads. Left ventricular ischemia of ≥ 10% on SPECT MPI was the diagnostic standard for substantial myocardial ischemia. HF-QRS analysis demonstrated incremental diagnostic value to ST evaluation plus clinical risk factors (AUC 0.804 vs 0.749, P < .0001). A HF-QRS + ST -analysis strategy identified 92.3% of subjects with substantial ischemia and no abnormality in 59.9% of the cohort. No cardiac events occurred in patients without substantial ischemia identified by HF-QRS analysis. CONCLUSIONS In this prospective analysis, exercise stress ECG with HF-QRS analysis identified any and substantial ischemia with high diagnostic accuracy and may allow more than half of referred patients to safely avoid imaging.
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Affiliation(s)
- Pelbreton C Balfour
- Cardiovascular Division, Department of Medicine, Cardiovascular Imaging Center, University of Virginia Health System, 1215 Lee Street, Box 800662, Charlottesville, VA, 22908, USA
| | - Jorge A Gonzalez
- Division of Cardiovascular Disease, Scripps Clinic, La Jolla, CA, USA
| | | | | | | | - Jack W Melson
- Cardiovascular Division, Department of Medicine, Cardiovascular Imaging Center, University of Virginia Health System, 1215 Lee Street, Box 800662, Charlottesville, VA, 22908, USA
| | - Michael Sobczak
- Cardiovascular Division, Department of Medicine, Cardiovascular Imaging Center, University of Virginia Health System, 1215 Lee Street, Box 800662, Charlottesville, VA, 22908, USA
| | - Valerie Izarnotegui
- Cardiovascular Division, Department of Medicine, Cardiovascular Imaging Center, University of Virginia Health System, 1215 Lee Street, Box 800662, Charlottesville, VA, 22908, USA
| | - Denny D Watson
- Cardiovascular Division, Department of Medicine, Cardiovascular Imaging Center, University of Virginia Health System, 1215 Lee Street, Box 800662, Charlottesville, VA, 22908, USA
- Departments of Radiology, University of Virginia Health System, Charlottesville, VA, USA
| | - George A Beller
- Cardiovascular Division, Department of Medicine, Cardiovascular Imaging Center, University of Virginia Health System, 1215 Lee Street, Box 800662, Charlottesville, VA, 22908, USA
- Departments of Radiology, University of Virginia Health System, Charlottesville, VA, USA
| | - Jamieson M Bourque
- Cardiovascular Division, Department of Medicine, Cardiovascular Imaging Center, University of Virginia Health System, 1215 Lee Street, Box 800662, Charlottesville, VA, 22908, USA.
- Departments of Radiology, University of Virginia Health System, Charlottesville, VA, USA.
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Kolosova KS, Grigoryeva NY, Kosyuga YI. High-Frequency ECG for Detection of Myocardial Ischemia Associated with Right Coronary Artery Stenosis in IHD Patients. Sovrem Tekhnologii Med 2020; 12:86-90. [PMID: 34513042 PMCID: PMC8353702 DOI: 10.17691/stm2020.12.1.11] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Indexed: 11/14/2022] Open
Abstract
The aim of the investigation was to study the parameters of high-frequency ECG in leads V1, V3R, V4R, V5R, V6R as additional diagnostic criteria for detecting the areas of myocardial ischemia associated with stenosis of the right coronary artery (RCA) in IHD patients. MATERIALS AND METHODS The study involved 47 patients who underwent selective coronary angiography (SCA) for detection of IHD. The patients were divided into two groups based on the SCA results: group 1 included 28 patients with hemodynamically significant RCA stenosis; group 2 consisted of 19 patients with hemodynamically non-significant RCA stenosis. Prior to SCA, all patients underwent resting high-frequency ECG recording in 12 conventional leads and in leads V3R-V6R for 5 min. The study also involved 15 volunteers with no history of cardiovascular disease or IHD symptoms (control group) who underwent ECG in the same leads. The resulting data were processed and analyzed using the ArMaSoft-12-Cardio software (©ArMaSoft, 1995-2019, Russia), which made it possible to determine the presence or absence of reduced amplitude zones (RAZ) of the QRS complex in all morphological variants, the root-mean-square (RMS) deviation, and excess kurtosis. RESULTS Statistically significant differences in the RAZ parameter of the QRS complex were revealed in high-frequency ECG of patients with hemodynamically significant and non-significant RCA stenosis. The RAZ sum in leads V1, V3R, V4R, V5R, V6R was 7.86±0.77 and 3.58±0.53, respectively, while in patients with no IHD signs, it equaled 1.87±0.43 (p=0.00001).The RMS value in patients with no IHD signs was 3.89±0.42, in patients with hemodynamically non-significant and significant RCA stenosis it equaled 3.51±0.34 and 2.73±0.24, respectively (p=0.008).The kurtosis value was statistically significantly higher in patients with hemodynamically significant stenosis (1.07±0.12), in contrast to those with hemodynamically non-significant stenosis and without IHD (0.78±0.05 and 0.64±0.03, respectively).An average correlation between the value of coronary stenosis and the sum of RAZ scores was found (r=0.66).However, RMS and kurtosis parameters correlate with the degree of RCA stenosis at a lower level.According to ROC analysis, the RAZ parameter showed better diagnostic results compared to RMS and kurtosis. Given the nonparametric nature of the available data, the prognostic capabilities of the studied parameters can be considered satisfactory as shown by the results of binary logistic regression. CONCLUSION The RAZ parameter of high-frequency ECG in leads V1, V3R, V4R, V5R, V6R may serve as an additional diagnostic criterion for identifying the areas of myocardial ischemia associated with RCA stenosis in IHD patients.
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Affiliation(s)
- K S Kolosova
- PhD Student, Department of Faculty and Polyclinic Therapy, Privolzhsky Research Medical University, 10/1 Minin and Pozharsky Square, Nizhny Novgorod, 603005, Russia
- Head of the Department of Faculty and Polyclinic Therapy, Privolzhsky Research Medical University, 10/1 Minin and Pozharsky Square, Nizhny Novgorod, 603005, Russia
- Associate Professor, Department of Pathological Physiology, Privolzhsky Research Medical University, 10/1 Minin and Pozharsky Square, Nizhny Novgorod, 603005, Russia
| | - N Yu Grigoryeva
- PhD Student, Department of Faculty and Polyclinic Therapy, Privolzhsky Research Medical University, 10/1 Minin and Pozharsky Square, Nizhny Novgorod, 603005, Russia
- Head of the Department of Faculty and Polyclinic Therapy, Privolzhsky Research Medical University, 10/1 Minin and Pozharsky Square, Nizhny Novgorod, 603005, Russia
- Associate Professor, Department of Pathological Physiology, Privolzhsky Research Medical University, 10/1 Minin and Pozharsky Square, Nizhny Novgorod, 603005, Russia
| | - Yu I Kosyuga
- PhD Student, Department of Faculty and Polyclinic Therapy, Privolzhsky Research Medical University, 10/1 Minin and Pozharsky Square, Nizhny Novgorod, 603005, Russia
- Head of the Department of Faculty and Polyclinic Therapy, Privolzhsky Research Medical University, 10/1 Minin and Pozharsky Square, Nizhny Novgorod, 603005, Russia
- Associate Professor, Department of Pathological Physiology, Privolzhsky Research Medical University, 10/1 Minin and Pozharsky Square, Nizhny Novgorod, 603005, Russia
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Golightly J, Shipman S, Owens R, Painter K. A Case of Acute Coronary Occlusion in a Morbidly Obese Patient Masked on Electrocardiogram by Low QRS Voltage. J Investig Med High Impact Case Rep 2020; 8:2324709620903133. [PMID: 31997664 PMCID: PMC6993149 DOI: 10.1177/2324709620903133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Accepted: 12/21/2019] [Indexed: 11/16/2022] Open
Abstract
Timely diagnosis of acute coronary occlusion is essential to avoid chronic cardiac impairment and death. We describe an uncommon case of acute myocardial infarction masked by low QRS voltage secondary to morbid obesity. This case highlights the importance of considering the degree of ST-segment elevation proportionally to the QRS amplitude if there is clinical suspicion of acute coronary occlusion.
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Affiliation(s)
| | - Stacia Shipman
- INTEGRIS Southwest Medical Center, Oklahoma City, OK, USA
| | - Ross Owens
- INTEGRIS Southwest Medical Center, Oklahoma City, OK, USA
| | - Kelly Painter
- INTEGRIS Southwest Medical Center, Oklahoma City, OK, USA
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Wagner J, Knaier R, Infanger D, Arbeev K, Briel M, Dieterle T, Hanssen H, Faude O, Roth R, Hinrichs T, Schmidt-Trucksäss A. Functional aging in health and heart failure: the COmPLETE Study. BMC Cardiovasc Disord 2019; 19:180. [PMID: 31362698 PMCID: PMC6664502 DOI: 10.1186/s12872-019-1164-6] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Accepted: 07/18/2019] [Indexed: 01/16/2023] Open
Abstract
BACKGROUND Cardiovascular (CV) diseases including heart failure are the leading causes of morbidity, with age being the primary risk factor. The combination of age-related organic functional impairment and reduced physical fitness can drastically impact an individual's healthspan. One's lifespan can potentially be prolonged by the preservation or improvement of physical fitness. However, it remains unclear as to which biomarkers are most suitable for distinguishing between healthy aging and the impaired organ function associated with heart failure. Therefore, a comprehensive assessment of the components of physical fitness and CV function will be performed to identify the most important factors contributing to aging in relation to both health and disease. METHODS This cross-sectional investigation will consist of two parts: COmPLETE-Health (C-Health) and COmPLETE-Heart (C-Heart). C-Health will examine the aging trajectories of physical fitness components and CV properties in a healthy population sample aged between 20 and 100 years (n = 490). Separately, C-Heart will assess the same markers in patients at different stages of chronic heart failure (n = 80). The primary outcome to determine the difference between C-Health and C-Heart will be cardiorespiratory fitness as measured by cardiopulmonary exercise testing on a bicycle ergometer. Secondary outcomes will include walking speed, balance, isometric strength, peak power, and handgrip strength. Physical activity as a behavioural component will be assessed objectively via accelerometry. Further, CV assessments will include pulse wave velocity; retinal, arterial, and venous diameters; brachial and retinal arterial endothelial function; carotid intima-media thickness; and systolic and diastolic function. The health distances for C-Health and C-Heart will be calculated using the methodology based on statistical (Mahalanobis) distance applied to measurements of quantitative biomarkers. DISCUSSION This research seeks to identify physical fitness and CV biomarkers that best resemble underlying CV risk with age. Further, it will examine which physical fitness markers are impaired most in heart failure. The presented integrative approach could define new recommendations for diagnostic guidance in aging. Ultimately, this study is expected to offer a better understanding of which functional characteristics should be specifically targeted in primary and secondary prevention to achieve an optimal healthspan.
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Affiliation(s)
- Jonathan Wagner
- Department of Sport, Exercise and Health, University of Basel, Birsstrasse 320 B, 4052 Basel, Switzerland
| | - Raphael Knaier
- Department of Sport, Exercise and Health, University of Basel, Birsstrasse 320 B, 4052 Basel, Switzerland
| | - Denis Infanger
- Department of Sport, Exercise and Health, University of Basel, Birsstrasse 320 B, 4052 Basel, Switzerland
| | - Konstantin Arbeev
- Biodemography of Aging Research Unit (BARU), Social Science Research Institute, Duke University, Durham, NC 27705 USA
| | - Matthias Briel
- Department of Clinical Research, Basel Institute for Clinical Epidemiology and Biostatistics, University Hospital Basel, Spitalstrasse 12, 4056 Basel, Switzerland
- Department of Health Research Methods, Evidence, and Impact, McMaster University, 1280 Main Street, Hamilton, ONL8S4K1 Canada
| | - Thomas Dieterle
- University Clinic of Medicine, Cantonal Hospital Baselland, University of Basel, Rheinstrasse 26, 4410 Liestal, Switzerland
| | - Henner Hanssen
- Department of Sport, Exercise and Health, University of Basel, Birsstrasse 320 B, 4052 Basel, Switzerland
| | - Oliver Faude
- Department of Sport, Exercise and Health, University of Basel, Birsstrasse 320 B, 4052 Basel, Switzerland
| | - Ralf Roth
- Department of Sport, Exercise and Health, University of Basel, Birsstrasse 320 B, 4052 Basel, Switzerland
| | - Timo Hinrichs
- Department of Sport, Exercise and Health, University of Basel, Birsstrasse 320 B, 4052 Basel, Switzerland
| | - Arno Schmidt-Trucksäss
- Department of Sport, Exercise and Health, University of Basel, Birsstrasse 320 B, 4052 Basel, Switzerland
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Analysis of the High-Frequency Content in Human QRS Complexes by the Continuous Wavelet Transform: An Automatized Analysis for the Prediction of Sudden Cardiac Death. SENSORS 2018; 18:s18020560. [PMID: 29439530 PMCID: PMC5854972 DOI: 10.3390/s18020560] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Revised: 02/06/2018] [Accepted: 02/07/2018] [Indexed: 02/07/2023]
Abstract
BACKGROUND Fragmentation and delayed potentials in the QRS signal of patients have been postulated as risk markers for Sudden Cardiac Death (SCD). The analysis of the high-frequency spectral content may be useful for quantification. METHODS Forty-two consecutive patients with prior history of SCD or malignant arrhythmias (patients) where compared with 120 healthy individuals (controls). The QRS complexes were extracted with a modified Pan-Tompkins algorithm and processed with the Continuous Wavelet Transform to analyze the high-frequency content (85-130 Hz). RESULTS Overall, the power of the high-frequency content was higher in patients compared with controls (170.9 vs. 47.3 10³nV²Hz-1; p = 0.007), with a prolonged time to reach the maximal power (68.9 vs. 64.8 ms; p = 0.002). An analysis of the signal intensity (instantaneous average of cumulative power), revealed a distinct function between patients and controls. The total intensity was higher in patients compared with controls (137.1 vs. 39 10³nV²Hz-1s-1; p = 0.001) and the time to reach the maximal intensity was also prolonged (88.7 vs. 82.1 ms; p < 0.001). DISCUSSION The high-frequency content of the QRS complexes was distinct between patients at risk of SCD and healthy controls. The wavelet transform is an efficient tool for spectral analysis of the QRS complexes that may contribute to stratification of risk.
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Maršánová L, Ronzhina M, Smíšek R, Vítek M, Němcová A, Smital L, Nováková M. ECG features and methods for automatic classification of ventricular premature and ischemic heartbeats: A comprehensive experimental study. Sci Rep 2017; 7:11239. [PMID: 28894131 PMCID: PMC5593838 DOI: 10.1038/s41598-017-10942-6] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2017] [Accepted: 08/16/2017] [Indexed: 11/16/2022] Open
Abstract
Accurate detection of cardiac pathological events is an important part of electrocardiogram (ECG) evaluation and subsequent correct treatment of the patient. The paper introduces the results of a complex study, where various aspects of automatic classification of various heartbeat types have been addressed. Particularly, non-ischemic, ischemic (of two different grades) and subsequent ventricular premature beats were classified in this combination for the first time. ECGs recorded in rabbit isolated hearts under non-ischemic and ischemic conditions were used for analysis. Various morphological and spectral features (both commonly used and newly proposed) as well as classification models were tested on the same data set. It was found that: a) morphological features are generally more suitable than spectral ones; b) successful results (accuracy up to 98.3% and 96.2% for morphological and spectral features, respectively) can be achieved using features calculated without time-consuming delineation of QRS-T segment; c) use of reduced number of features (3 to 14 features) for model training allows achieving similar or even better performance as compared to the whole feature sets (10 to 29 features); d) k-nearest neighbours and support vector machine seem to be the most appropriate models (accuracy up to 98.6% and 93.5%, respectively).
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Affiliation(s)
- Lucie Maršánová
- Department of Biomedical Engineering, Faculty of Electrical Engineering and Communication, Brno University of Technology, Technická 12, Brno, 616 00, Czech Republic.
| | - Marina Ronzhina
- Department of Biomedical Engineering, Faculty of Electrical Engineering and Communication, Brno University of Technology, Technická 12, Brno, 616 00, Czech Republic
| | - Radovan Smíšek
- Department of Biomedical Engineering, Faculty of Electrical Engineering and Communication, Brno University of Technology, Technická 12, Brno, 616 00, Czech Republic
- Institute of Scientific Instruments, The Czech Academy of Sciences, Královopolská 147, Brno, 612 64, Czech Republic
| | - Martin Vítek
- Department of Biomedical Engineering, Faculty of Electrical Engineering and Communication, Brno University of Technology, Technická 12, Brno, 616 00, Czech Republic
| | - Andrea Němcová
- Department of Biomedical Engineering, Faculty of Electrical Engineering and Communication, Brno University of Technology, Technická 12, Brno, 616 00, Czech Republic
| | - Lukas Smital
- Department of Biomedical Engineering, Faculty of Electrical Engineering and Communication, Brno University of Technology, Technická 12, Brno, 616 00, Czech Republic
| | - Marie Nováková
- Department of Physiology, Faculty of Medicine, Masaryk University, Kamenice 5, Brno, 625 00, Czech Republic
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Tsutsumi T, Okamoto Y, Takano N, Wakatsuki D, Tomaru T, Nakajima T. High-frequency power within the QRS complex in ischemic cardiomyopathy patients with ventricular arrhythmias: Insights from a clinical study and computer simulation of cardiac fibrous tissue. Comput Biol Med 2017; 87:132-140. [PMID: 28591674 DOI: 10.1016/j.compbiomed.2017.05.022] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Revised: 05/18/2017] [Accepted: 05/19/2017] [Indexed: 10/19/2022]
Abstract
BACKGROUND The distribution of frequency power (DFP) within the QRS complex (QRS) is unclear. This study aimed to investigate the DFP within the QRS in ischemic cardiomyopathy (ICM) with lethal ventricular arrhythmias (L-VA). A computer simulation was performed to explore the mechanism of abnormal frequency power. METHODS The study included 31 ICM patients with and without L-VA (n = 10 and 21, respectively). We applied the continuous wavelet transform to measure the time-frequency power within the QRS. Integrated time-frequency power (ITFP) was measured within the frequency range of 5-300 Hz. The simulation model consisted of two-dimensional myocardial tissues intermingled with fibroblasts. We examined the relation between frequency power calculated from the simulated QRS and the fibroblast-to-myocyte ratio (r) of the model. RESULTS The frequency powers significantly increased from 180 to 300 Hz and from 5 to 15 Hz, and also decreased from 45 to 80 Hz in patients with ICM and L-VA compared with the normal individuals. They increased from 110 Hz to 250 Hz in ICM alone. In the simulation, the high-frequency power increased when the ratio (r) were 2.0-2.5. Functional reentry was initiated if the ratio (r) increased to 2.0. CONCLUSIONS Abnormal higher-frequency power (180-300 Hz) may provide arrhythmogenic signals in ICM with L-VA that may be associated with the fibrous tissue proliferation.
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Affiliation(s)
- Takeshi Tsutsumi
- Division of Cardiology, Eda Memorial Hospital, Yokohama, 225-0012, Japan.
| | - Yoshiwo Okamoto
- Department of Electrical, Electronics and Computer Engineering, Faculty of Engineering, Chiba Institute of Technology, Narashino, 275-0016, Japan
| | - Nami Takano
- Center for Health Check-up and Preventive Medicine, Kanto Central Hospital, Tokyo, 154-0098, Japan
| | - Daisuke Wakatsuki
- Division of Cardiology, Showa University Fujigaoka Hospital, Yokohama, 227-8501, Japan
| | - Takanobu Tomaru
- Intensive Care Unit and Clinical Physiology Department, Cardiology Division, Toho University Medical Center, Sakura Hospital, Sakura, 285-8741, Japan
| | - Toshiaki Nakajima
- Department of Cardiovascular Medicine, Dokkyo Medical University, 880 Kitakobayashi, Mibu, Tochigi, 321-0293, Japan
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Ventricular dyssynchrony assessment using ultra-high frequency ECG technique. J Interv Card Electrophysiol 2017; 49:245-254. [PMID: 28695377 PMCID: PMC5543201 DOI: 10.1007/s10840-017-0268-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Accepted: 06/20/2017] [Indexed: 11/17/2022]
Abstract
Purpose The aim of this proof-of-concept study is to introduce new high-dynamic ECG technique with potential to detect temporal-spatial distribution of ventricular electrical depolarization and to assess the level of ventricular dyssynchrony. Methods 5-kHz 12-lead ECG data was collected. The amplitude envelopes of the QRS were computed in an ultra-high frequency band of 500–1000 Hz and were averaged (UHFQRS). UHFQRS V lead maps were compiled, and numerical descriptor identifying ventricular dyssynchrony (UHFDYS) was detected. Results An electrical UHFQRS maps describe the ventricular dyssynchrony distribution in resolution of milliseconds and correlate with strain rate results obtained by speckle tracking echocardiography. The effect of biventricular stimulation is demonstrated by the UHFQRS morphology and by the UHFDYS descriptor in selected examples. Conclusions UHFQRS offers a new and simple technique for assessing electrical activation patterns in ventricular dyssynchrony with a temporal-spatial resolution that cannot be obtained by processing standard surface ECG. The main clinical potential of UHFQRS lies in the identification of differences in electrical activation among CRT candidates and detection of improvements in electrical synchrony in patients with biventricular pacing. Electronic supplementary material The online version of this article (doi:10.1007/s10840-017-0268-0) contains supplementary material, which is available to authorized users.
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13
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Galante O, Amit G, Granot Y, Davrath LR, Abboud S, Zahger D. High-frequency QRS analysis in the evaluation of chest pain in the emergency department. J Electrocardiol 2017; 50:457-465. [DOI: 10.1016/j.jelectrocard.2017.02.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2016] [Indexed: 11/24/2022]
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14
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Wagener M, Abächerli R, Honegger U, Schaerli N, Prêtre G, Twerenbold R, Puelacher C, Sunier G, Reddiess P, Rubini Gimenez M, Wildi K, Boeddinghaus J, Nestelberger T, Badertscher P, Sabti Z, Schmid R, Leber R, Widmer DF, Shrestha S, Strebel I, Wild D, Osswald S, Zellweger M, Mueller C, Reichlin T. Diagnostic and Prognostic Value of Lead aVR During Exercise Testing in Patients Suspected of Having Myocardial Ischemia. Am J Cardiol 2017; 119:959-966. [PMID: 28215415 DOI: 10.1016/j.amjcard.2016.11.056] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Revised: 11/29/2016] [Accepted: 11/29/2016] [Indexed: 11/26/2022]
Abstract
We aimed to assess the diagnostic and prognostic value of ST-segment deviation in aVR, a lead often ignored in clinical practice, during exercise testing and to compare it to the most widely used criterion of ST-segment depression in V5. We enrolled 1,596 patients with suspected myocardial ischemia referred for nuclear perfusion imaging undergoing bicycle stress testing. ST-segment amplitudes in leads aVR and V5 were automatically measured. The presence of inducible myocardial ischemia was the diagnostic end point and adjudicated based on nuclear perfusion imaging and coronary angiography. Major adverse cardiac events (MACE) during 2 years of follow-up including death, acute myocardial infarction, and coronary revascularization were the prognostic end point. Exercise-induced myocardial ischemia was detected in 470 patients (29%). Median ST amplitudes for leads aVR and V5 differed significantly among patients with and without ischemia (p <0.01). The diagnostic accuracy of ST changes for myocardial ischemia as quantified by the area under the receiver operating characteristic curve was highest 2 minutes into recovery and similar in aVR and V5 (0.62, 95% confidence interval CI 0.60 to 0.65 vs 0.60, 95% confidence interval 0.58 to 0.63, p = 0.08 for comparison). In multivariate analysis, ST changes in lead aVR, but not lead V5, contributed independent diagnostic information on top of clinical parameters and manual electrocardiographic interpretation. Within 2 years of follow-up, MACE occurred in 33% of patients with ST elevations in aVR and in 16% without (p <0.001). In conclusion, ST elevation in lead aVR during exercise testing indicates inducible myocardial ischemia independently of ST depressions in lead V5 and clinical factors and also predicts MACE during follow-up.
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15
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Puelacher C, Wagener M, Abächerli R, Honegger U, Lhasam N, Schaerli N, Prêtre G, Strebel I, Twerenbold R, Boeddinghaus J, Nestelberger T, Rubini Giménez M, Hillinger P, Wildi K, Sabti Z, Badertscher P, Cupa J, Kozhuharov N, du Fay de Lavallaz J, Freese M, Roux I, Lohrmann J, Leber R, Osswald S, Wild D, Zellweger MJ, Mueller C, Reichlin T. Diagnostic value of ST-segment deviations during cardiac exercise stress testing: Systematic comparison of different ECG leads and time-points. Int J Cardiol 2017; 238:166-172. [PMID: 28320607 DOI: 10.1016/j.ijcard.2017.02.079] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/07/2016] [Revised: 01/18/2017] [Accepted: 02/20/2017] [Indexed: 11/17/2022]
Abstract
BACKGROUND Exercise ECG stress testing is the most widely available method for evaluation of patients with suspected myocardial ischemia. Its major limitation is the relatively poor accuracy of ST-segment changes regarding ischemia detection. Little is known about the optimal method to assess ST-deviations. METHODS A total of 1558 consecutive patients undergoing bicycle exercise stress myocardial perfusion imaging (MPI) were enrolled. Presence of inducible myocardial ischemia was adjudicated using MPI results. The diagnostic value of ST-deviations for detection of exercise-induced myocardial ischemia was systematically analyzed 1) for each individual lead, 2) at three different intervals after the J-point (J+40ms, J+60ms, J+80ms), and 3) at different time points during the test (baseline, maximal workload, 2min into recovery). RESULTS Exercise-induced ischemia was detected in 481 (31%) patients. The diagnostic accuracy of ST-deviations was highest at +80ms after the J-point, and at 2min into recovery. At this point, ST-amplitude showed an AUC of 0.63 (95% CI 0.59-0.66) for the best-performing lead I. The combination of ST-amplitude and ST-slope in lead I did not increase the AUC. Lead I reached a sensitivity of 37% and a specificity of 83%, with similar sensitivity to manual ECG analysis (34%, p=0.31) but lower specificity (90%, p<0.001). CONCLUSION When using ECG stress testing for evaluation of patients with suspected myocardial ischemia, the diagnostic accuracy of ST-deviations is highest when evaluated at +80ms after the J-point, and at 2min into recovery.
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Affiliation(s)
- Christian Puelacher
- Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, University Basel, Switzerland
| | - Max Wagener
- Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, University Basel, Switzerland
| | - Roger Abächerli
- Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, University Basel, Switzerland; Research, Schiller AG, Baar, Switzerland; Lucerne University of Applied Sciences and Arts (HSLU), Horw, Switzerland
| | - Ursina Honegger
- Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, University Basel, Switzerland
| | - Nundsin Lhasam
- Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, University Basel, Switzerland
| | - Nicolas Schaerli
- Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, University Basel, Switzerland
| | - Gil Prêtre
- Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, University Basel, Switzerland
| | - Ivo Strebel
- Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, University Basel, Switzerland
| | - Raphael Twerenbold
- Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, University Basel, Switzerland
| | - Jasper Boeddinghaus
- Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, University Basel, Switzerland
| | - Thomas Nestelberger
- Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, University Basel, Switzerland
| | - Maria Rubini Giménez
- Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, University Basel, Switzerland
| | - Petra Hillinger
- Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, University Basel, Switzerland
| | - Karin Wildi
- Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, University Basel, Switzerland
| | - Zaid Sabti
- Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, University Basel, Switzerland
| | - Patrick Badertscher
- Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, University Basel, Switzerland
| | - Janosch Cupa
- Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, University Basel, Switzerland
| | - Nikola Kozhuharov
- Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, University Basel, Switzerland
| | - Jeanne du Fay de Lavallaz
- Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, University Basel, Switzerland
| | - Michael Freese
- Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, University Basel, Switzerland
| | - Isabelle Roux
- Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, University Basel, Switzerland
| | - Jens Lohrmann
- Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, University Basel, Switzerland
| | - Remo Leber
- Research, Schiller AG, Baar, Switzerland
| | - Stefan Osswald
- Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, University Basel, Switzerland
| | - Damian Wild
- Division of Nuclear Medicine, University Hospital Basel, University Basel, Switzerland
| | - Michael J Zellweger
- Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, University Basel, Switzerland
| | - Christian Mueller
- Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, University Basel, Switzerland
| | - Tobias Reichlin
- Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, University Basel, Switzerland.
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Leinveber P, Halamek J, Jurak P. Ambulatory monitoring of myocardial ischemia in the 21st century-an opportunity for high frequency QRS analysis. J Electrocardiol 2016; 49:902-906. [PMID: 27590215 DOI: 10.1016/j.jelectrocard.2016.07.034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Indexed: 10/21/2022]
Abstract
Ambulatory monitoring represents an effective tool for the assessment of silent and transient myocardial ischemia during routine daily activities. Incidence of silent ischemia can provide important prognostic information about patients with coronary artery disease or acute coronary syndrome, as well as about post-myocardial infarction patients. The current technological progress enables development of powerful and miniaturized wearable devices for Holter monitoring. Higher sampling rates, dynamic range, and extended computational and storage capacity allow for considering of more complex methodological solutions such as high-frequency QRS analysis for diagnosing myocardial ischemia. Implementation of suitable methodologies for advanced detection of myocardial ischemia into modern ambulatory monitoring devices creates the potential of making the ambulatory myocardial ischemia monitoring a valuable diagnostic tool in clinical practice.
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Affiliation(s)
- Pavel Leinveber
- International Clinical Research Center, St. Anne's University Hospital, Brno, Czech Republic; Institute of Scientific Instruments of the Czech Academy of Sciences, Czech Republic.
| | - Josef Halamek
- International Clinical Research Center, St. Anne's University Hospital, Brno, Czech Republic; Institute of Scientific Instruments of the Czech Academy of Sciences, Czech Republic
| | - Pavel Jurak
- International Clinical Research Center, St. Anne's University Hospital, Brno, Czech Republic; Institute of Scientific Instruments of the Czech Academy of Sciences, Czech Republic
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Jurak P, Halamek J, Plesinger F, Reichlova T, Vondra V, Viscor I, Leinveber P. Can we hear ventricle dyssynchrony? Yes, we can. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2016; 2015:6527-30. [PMID: 26737788 DOI: 10.1109/embc.2015.7319888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
This study introduces a method for detection of ventricular depolarization activity and the transfer of this activity into an audible stereo audio signal. Heart potentials are measured by an ultra-high-frequency high-dynamic-range electrocardiograph (UHF-ECG) with a 25-kHz sampling rate. Averaged and prolonged UHF amplitude envelopes of V1-3 and V4-6 leads at a frequency range of 500-1000 Hz are used as a modulating function for two carrier audio frequencies. The right speaker makes it possible to listen to the depolarization of the septum and right ventricle (V1-3) and the left speaker the left ventricle lateral wall (V4-6). In the healthy heart, both speakers can be heard simultaneously. A delayed L or R speaker represents the dyssynchronous electrical activation of the ventricles. Examples of the normal heart, right bundle branch block and left bundle branch block can be heard at www.medisig.com/uhfecg.
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Rauber M, Štajer D, Noč M, Schlegel TT, Starc V. High resolution ECG-aided early prognostic model for comatose survivors of out of hospital cardiac arrest. J Electrocardiol 2015; 48:544-50. [DOI: 10.1016/j.jelectrocard.2015.04.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2014] [Indexed: 10/23/2022]
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Intra-QRS spectral changes accompany ST segment changes during episodes of myocardial ischemia. J Electrocardiol 2014; 48:115-22. [PMID: 25266140 DOI: 10.1016/j.jelectrocard.2014.09.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2014] [Indexed: 11/22/2022]
Abstract
BACKGROUND Coronary artery disease and myocardial ischemia cause substantial morbidity and mortality. While ischemia is traditionally diagnosed on the 12-lead electrocardiogram (ECG) by shifts in the ST segment, electrical changes are also produced within the QRS complex during depolarization of ischemic ventricular tissue, though these are often of small amplitude and can be missed in traditional ECG analysis. We explore the utility of an easily implemented spectral analysis method for detecting intra-QRS changes during episodes of myocardial ischemia, using Holter recordings from the European ST-T database. METHODS Time-frequency distributions of QRS complexes from each recording were computed using the continuous wavelet transform. Indices corresponding to frequency content of four overlapping frequency bands were computed: F1 (24-35Hz), F2 (30-45Hz), F3 (40-60Hz), and F4 (50-80Hz). Values of these indices were compared during annotated episodes of ST change and during a baseline during the recording. RESULTS Marked changes in intra-QRS frequency content were identified during ischemia, grouped by ECG lead analyzed. In lead III, a pronounced and statistically significant increase in the highest frequency sub-bands (F3 and F4) was consistently observed. Analysis of anterior precordial leads also showed significant increases in F4. CONCLUSIONS Intra-QRS time-frequency analysis using the continuous wavelet transform can identify a spectral signature corresponding to myocardial ischemia in the range 24-80Hz. Intra-QRS spectral analysis has the potential for many clinical applications.
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Laguna P, Sörnmo L. The STAFF III ECG database and its significance for methodological development and evaluation. J Electrocardiol 2014; 47:408-17. [DOI: 10.1016/j.jelectrocard.2014.04.018] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2014] [Indexed: 10/25/2022]
Affiliation(s)
- Pablo Laguna
- The BioSignal Interpretation and Computational Simulation Group (BSICoS), Aragón Institute of Engineering Research (I3A), Universidad de Zaragoza, Zaragoza, Spain; The Centro de Investigación Biomédica en Red en Bioingeniería, Biomateriales y Nanomedicina (CIBERBBN), Zaragoza, Spain
| | - Leif Sörnmo
- The Department of Biomedical Engineering and Center for Integrative Electrocardiology, Lund University, Lund, Sweden.
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Pahlm O, Wagner GS. QRS, ST and T changes of acute transmural myocardial ischemia: Overview editorial. J Electrocardiol 2014; 47:397-401. [DOI: 10.1016/j.jelectrocard.2014.05.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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