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Nomoto M, Suzuki A, Shiga T, Shoda M, Hagiwara N. Impact of signal-averaged electrocardiography findings on appropriate shocks in prophylactic implantable cardioverter defibrillator patients with nonischemic systolic heart failure. BMC Cardiovasc Disord 2022; 22:374. [PMID: 35974317 PMCID: PMC9382808 DOI: 10.1186/s12872-022-02811-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2022] [Accepted: 08/08/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Appropriate shock therapy is associated with subsequent all-cause death in heart failure (HF) patients who receive an implantable cardioverter defibrillator (ICD) for the primary prevention of sudden cardiac death. To evaluate the impact of signal-averaged electrocardiography (SAECG) findings on appropriate shocks in prophylactic ICD patients with nonischemic systolic HF. METHODS We studied 86 patients with nonischemic HF and a left ventricular ejection fraction ≤ 35% who underwent new ICD implantation for the primary prevention of sudden cardiac death. We excluded patients who had a previously implanted permanent pacemaker and patients who received cardiac resynchronization therapy with an ICD. SAECG was performed before implantation. Abnormal SAECG findings were defined if 2 of the following 3 conditions were identified: filtered QRS duration (fQRS) ≥ 114 ms, root-mean-square voltage during the last 40 ms of the fQRS (RMS 40) < 20 μV, and duration of the low-amplitude potentials < 40 μV (LAS 40) > 38 ms; additionally, patients with a QRS complex ≥ 120 ms who met both the RMS 40 and LAS 40 criteria were also considered to have abnormal SAECG findings. The primary outcome was the first occurrence of appropriate shock after implantation of the ICD. The secondary outcomes were the first occurrence of inappropriate shock and all-cause mortality. RESULTS Forty-two patients met the criteria for abnormal SAECG findings (49%). During a median follow-up period of 61 months, 17 patients (20%) died, 24 (28%) received appropriate shock therapy, and 19 (22%) received inappropriate shock therapy. There was a significantly higher incidence of appropriate shocks in patients with abnormal SAECG findings than in those with normal SAECG findings (log-rank test, p = 0.025). Multivariate analysis revealed that abnormal SAECG findings were independently associated with the occurrence of appropriate shock (hazard ratio 2.67, 95% confidential interval 1.14-6.26). However, abnormal SAECG findings were not related to inappropriate shock. There was no difference in the incidence of all-cause death between patients with abnormal and normal SAECG findings. CONCLUSIONS Our results suggest that abnormal SAECG findings are associated with a high probability of appropriate shocks in prophylactic ICD patients with nonischemic systolic HF.
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Affiliation(s)
- Michiru Nomoto
- Department of Cardiology, Tokyo Women's Medical University, Tokyo, Japan
| | - Atsushi Suzuki
- Department of Cardiology, Tokyo Women's Medical University, Tokyo, Japan
| | - Tsuyoshi Shiga
- Department of Cardiology, Tokyo Women's Medical University, Tokyo, Japan. .,Department of Clinical Pharmacology and Therapeutics, The Jikei University School of Medicine, 3-25-8 Nishi-shinbashi, Minato-ku, Tokyo, 105-8461, Japan.
| | - Morio Shoda
- Clinical Research Division for Heart Rhythm Management, Tokyo Women's Medical University, Tokyo, Japan
| | - Nobuhisa Hagiwara
- Department of Cardiology, Tokyo Women's Medical University, Tokyo, Japan
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Tachmatzidis D, Tsarouchas A, Mouselimis D, Filos D, Antoniadis AP, Lysitsas DN, Mezilis N, Sakellaropoulou A, Giannopoulos G, Bakogiannis C, Triantafyllou K, Fragakis N, Letsas KP, Asvestas D, Efremidis M, Lazaridis C, Chouvarda I, Vassilikos VP. P-Wave Beat-to-Beat Analysis to Predict Atrial Fibrillation Recurrence after Catheter Ablation. Diagnostics (Basel) 2022; 12:diagnostics12040830. [PMID: 35453877 PMCID: PMC9028701 DOI: 10.3390/diagnostics12040830] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2022] [Revised: 03/17/2022] [Accepted: 03/24/2022] [Indexed: 11/23/2022] Open
Abstract
The identification of patients prone to atrial fibrillation (AF) relapse after catheter ablation is essential for better patient selection and risk stratification. The current prospective cohort study aims to validate a novel P-wave index based on beat-to-beat (B2B) P-wave morphological and wavelet analysis designed to detect patients with low burden AF as a predictor of AF recurrence within a year after successful catheter ablation. From a total of 138 consecutive patients scheduled for AF ablation, 12-lead ECG and 10 min vectorcardiogram (VCG) recordings were obtained. Univariate analysis revealed that patients with higher B2B P-wave index had a two-fold risk for AF recurrence (HR: 2.35, 95% CI: 1.24–4.44, p: 0.010), along with prolonged P-wave, interatrial block, early AF recurrence, female gender, heart failure history, previous stroke, and CHA2DS2-VASc score. Multivariate analysis of assessable predictors before ablation revealed that B2B P-wave index, along with heart failure history and a history of previous stroke or transient ischemic attack, are independent predicting factors of atrial fibrillation recurrence. Further studies are needed to assess the predictive value of the B2B index with greater accuracy and evaluate a possible relationship with atrial substrate analysis.
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Affiliation(s)
- Dimitrios Tachmatzidis
- 3rd Cardiology Department, Hippokrateion University Hospital, Aristotle University of Thessaloniki, 546 42 Thessaloniki, Greece; (A.T.); (D.M.); (A.P.A.); (G.G.); (C.B.); (K.T.); (N.F.); (C.L.); (V.P.V.)
- Correspondence:
| | - Anastasios Tsarouchas
- 3rd Cardiology Department, Hippokrateion University Hospital, Aristotle University of Thessaloniki, 546 42 Thessaloniki, Greece; (A.T.); (D.M.); (A.P.A.); (G.G.); (C.B.); (K.T.); (N.F.); (C.L.); (V.P.V.)
| | - Dimitrios Mouselimis
- 3rd Cardiology Department, Hippokrateion University Hospital, Aristotle University of Thessaloniki, 546 42 Thessaloniki, Greece; (A.T.); (D.M.); (A.P.A.); (G.G.); (C.B.); (K.T.); (N.F.); (C.L.); (V.P.V.)
| | - Dimitrios Filos
- Lab of Computing, Medical Informatics and Biomedical Imaging Technologies, School of Medicine, Aristotle University of Thessaloniki, 541 24 Thessaloniki, Greece; (D.F.); (I.C.)
| | - Antonios P. Antoniadis
- 3rd Cardiology Department, Hippokrateion University Hospital, Aristotle University of Thessaloniki, 546 42 Thessaloniki, Greece; (A.T.); (D.M.); (A.P.A.); (G.G.); (C.B.); (K.T.); (N.F.); (C.L.); (V.P.V.)
| | | | - Nikolaos Mezilis
- St. Luke’s Hospital Thessaloniki, 552 36 Thessaloniki, Greece; (D.N.L.); (N.M.)
| | - Antigoni Sakellaropoulou
- Electrophysiology Laboratory, 2nd Department of Cardiology, Evangelismos General Hospital of Athens, 106 76 Athens, Greece; (A.S.); (K.P.L.); (D.A.); (M.E.)
| | - Georgios Giannopoulos
- 3rd Cardiology Department, Hippokrateion University Hospital, Aristotle University of Thessaloniki, 546 42 Thessaloniki, Greece; (A.T.); (D.M.); (A.P.A.); (G.G.); (C.B.); (K.T.); (N.F.); (C.L.); (V.P.V.)
| | - Constantinos Bakogiannis
- 3rd Cardiology Department, Hippokrateion University Hospital, Aristotle University of Thessaloniki, 546 42 Thessaloniki, Greece; (A.T.); (D.M.); (A.P.A.); (G.G.); (C.B.); (K.T.); (N.F.); (C.L.); (V.P.V.)
| | - Konstantinos Triantafyllou
- 3rd Cardiology Department, Hippokrateion University Hospital, Aristotle University of Thessaloniki, 546 42 Thessaloniki, Greece; (A.T.); (D.M.); (A.P.A.); (G.G.); (C.B.); (K.T.); (N.F.); (C.L.); (V.P.V.)
| | - Nikolaos Fragakis
- 3rd Cardiology Department, Hippokrateion University Hospital, Aristotle University of Thessaloniki, 546 42 Thessaloniki, Greece; (A.T.); (D.M.); (A.P.A.); (G.G.); (C.B.); (K.T.); (N.F.); (C.L.); (V.P.V.)
| | - Konstantinos P. Letsas
- Electrophysiology Laboratory, 2nd Department of Cardiology, Evangelismos General Hospital of Athens, 106 76 Athens, Greece; (A.S.); (K.P.L.); (D.A.); (M.E.)
| | - Dimitrios Asvestas
- Electrophysiology Laboratory, 2nd Department of Cardiology, Evangelismos General Hospital of Athens, 106 76 Athens, Greece; (A.S.); (K.P.L.); (D.A.); (M.E.)
| | - Michael Efremidis
- Electrophysiology Laboratory, 2nd Department of Cardiology, Evangelismos General Hospital of Athens, 106 76 Athens, Greece; (A.S.); (K.P.L.); (D.A.); (M.E.)
| | - Charalampos Lazaridis
- 3rd Cardiology Department, Hippokrateion University Hospital, Aristotle University of Thessaloniki, 546 42 Thessaloniki, Greece; (A.T.); (D.M.); (A.P.A.); (G.G.); (C.B.); (K.T.); (N.F.); (C.L.); (V.P.V.)
| | - Ioanna Chouvarda
- Lab of Computing, Medical Informatics and Biomedical Imaging Technologies, School of Medicine, Aristotle University of Thessaloniki, 541 24 Thessaloniki, Greece; (D.F.); (I.C.)
| | - Vassilios P. Vassilikos
- 3rd Cardiology Department, Hippokrateion University Hospital, Aristotle University of Thessaloniki, 546 42 Thessaloniki, Greece; (A.T.); (D.M.); (A.P.A.); (G.G.); (C.B.); (K.T.); (N.F.); (C.L.); (V.P.V.)
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Yodogawa K, Ohara T, Murata H, Iwasaki YK, Seino Y, Shimizu W. Detection of arrhythmogenic substrate within QRS complex in patients with cardiac sarcoidosis using wavelet-transformed ECG. Heart Vessels 2020; 35:1148-1153. [PMID: 32185494 DOI: 10.1007/s00380-020-01584-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Accepted: 03/06/2020] [Indexed: 10/24/2022]
Abstract
Signal-averaged electrocardiography (SAECG) has been known to be useful for prediction of lethal ventricular arrhythmias (VA). However, this technique has limitations in patients with intraventricular conduction disturbance (IVCD), which is common in cardiac sarcoidosis (CS). Meanwhile, wavelet-transformed ECG (WTECG) has been reported to be useful for detecting arrhythmogenic substrate hidden within QRS complex. The objective of this study was to assess the utility of WTECG for detecting arrhythmogenic substrate in patients with CS. Forty-four CS patients including 18 patients with VA were retrospectively investigated. The parameters on the signal-averaged electrocardiography (SAECG) and the power of frequency components on WTECG were compared between VA group and non-VA group. Eighteen patients have VA (VT: n = 17, VF: n = 1). LP were detected in 17 in VA group and 24 in non-VA group. WTECG showed that high-frequency components (HFC; 80-150 Hz) were developed in VA group. Peak power value at 150 Hz (P150) was significantly higher in VA group than that in non-VA group (442.9 ± 160.2 vs 316.7 ± 100.8, p = 0.006). The receiver operating characteristic (ROC) curve analysis showed an optimal cutoff point of 336 of P150 for detecting patients with VA, with 82.4% sensitivity, 61.5% specificity, and area under the curve of 0.74 (95% confidence interval [CI] 0.59-0.89). WTECG may be useful for detecting CS patients who are prone to VA.
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Affiliation(s)
- Kenji Yodogawa
- Department of Cardiovascular Medicine, Nippon Medical School, 1-1-5, Sendagi, Bunkyo-ku, Tokyo, 113-8603, Japan.
| | - Toshihiko Ohara
- Department of General Medicine and Health Science, Nippon Medical School, Tokyo, Japan
| | - Hiroshige Murata
- Department of Cardiovascular Medicine, Nippon Medical School, 1-1-5, Sendagi, Bunkyo-ku, Tokyo, 113-8603, Japan
| | - Yu-Ki Iwasaki
- Department of Cardiovascular Medicine, Nippon Medical School, 1-1-5, Sendagi, Bunkyo-ku, Tokyo, 113-8603, Japan
| | - Yoshihiko Seino
- Department of Cardiology, Nippon Medical School Chiba Hokusoh Hospital, Chiba, Japan
| | - Wataru Shimizu
- Department of Cardiovascular Medicine, Nippon Medical School, 1-1-5, Sendagi, Bunkyo-ku, Tokyo, 113-8603, Japan
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QRS analysis using wavelet transformation for the prediction of response to cardiac resynchronization therapy: a prospective pilot study. J Electrocardiol 2013; 47:59-65. [PMID: 24034302 DOI: 10.1016/j.jelectrocard.2013.08.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2013] [Indexed: 11/20/2022]
Abstract
BACKGROUND Wider QRS and left bundle branch block morphology are related to response to cardiac resynchronization therapy (CRT). A novel time-frequency analysis of the QRS complex may provide additional information in predicting response to CRT. METHODS Signal-averaged electrocardiograms were prospectively recorded, before CRT, in orthogonal leads and QRS decomposition in three frequency bands was performed using the Morlet wavelet transformation. RESULTS Thirty eight patients (age 65±10years, 31 males) were studied. CRT responders (n=28) had wider baseline QRS compared to non-responders and lower QRS energies in all frequency bands. The combination of QRS duration and mean energy in the high frequency band had the best predicting ability (AUC 0.833, 95%CI 0.705-0.962, p=0.002) followed by the maximum energy in the high frequency band (AUC 0.811, 95%CI 0.663-0.960, p=0.004). CONCLUSIONS Wavelet transformation of the QRS complex is useful in predicting response to CRT.
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Affiliation(s)
- Marek Malik
- St. Paul's Cardiac Electrophysiology and St. George's, University of London, London, UK
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Yodogawa K, Morita N, Kobayashi Y, Takayama H, Ohara T, Seino Y, Katoh T, Mizuno K. A new approach for the comparison of conduction abnormality between arrhythmogenic right ventricular cardiomyopathy/dysplasia and Brugada syndrome. Ann Noninvasive Electrocardiol 2011; 16:263-9. [PMID: 21762254 DOI: 10.1111/j.1542-474x.2011.00441.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND Right ventricular outflow tract ventricular tachycardia (RVOT-VT), arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/ARVD), and Brugada syndrome (BrS) were characterized by arrhythmias originating in the right ventricle, and the pathophysiologic mechanism underlying these arrhythmias has not been fully understood. METHODS This study consisted of 40 subjects, including 20 patients with RVOT-VT, 10 patients with BrS, and 10 ARVD patients. The parameters on the signal-averaged electrocardiography (ECG) and the frequency components recorded from the wavelet-transformed ECG were compared between the three groups. Late potentials were positive in none of the patients with RVOT-VT, seven of the patients with BrS, and all of ARVD patients. RESULTS In Brugada and ARVD patients, the power of high-frequency components (80-150 Hz) was developed to a greater extent than in RVOT-VT patients. In the power analysis of the high-frequency components between BrS and ARVD, the frequency showing the greatest power was significantly higher in ARVD patients than that in BrS patients (145.4 ± 27.9 Hz vs 81.7 ± 19.9 Hz, P < 0.01). CONCLUSIONS High-frequency components were developed in ARVD and BrS, but not in RVOT-VT. The frequency levels showing high power by wavelet analysis obviously differ between ARVD and BrS. Wavelet analysis may provide new insight into unsolved mechanisms in arrhythmogenic right heart disease.
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Affiliation(s)
- Kenji Yodogawa
- Division of Cardiology, Department of Internal Medicine, Nippon Medical School Chiba Hokusoh Hospital, Chiba, Japan.
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7
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Yodogawa K, Ohara T, Takayama H, Seino Y, Katoh T, Mizuno K. Detection of Prior Myocardial Infarction Patients Prone to Malignant Ventricular Arrhythmias Using Wavelet Transform Analysis. Int Heart J 2011; 52:286-9. [DOI: 10.1536/ihj.52.286] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Affiliation(s)
- Kenji Yodogawa
- Division of Cardiology, Department of Internal Medicine, Nippon Medical School Chiba Hokusoh Hospital
| | - Toshihiko Ohara
- Division of Cardiology, Hepatology, Geriatrics, and Integrated Medicine, Department of Internal Medicine, Nippon Medical School
| | - Hideo Takayama
- Division of Cardiology, Hepatology, Geriatrics, and Integrated Medicine, Department of Internal Medicine, Nippon Medical School
| | - Yoshihiko Seino
- Division of Cardiology, Department of Internal Medicine, Nippon Medical School Chiba Hokusoh Hospital
| | - Takao Katoh
- Division of Cardiology, Hepatology, Geriatrics, and Integrated Medicine, Department of Internal Medicine, Nippon Medical School
| | - Kyoichi Mizuno
- Division of Cardiology, Hepatology, Geriatrics, and Integrated Medicine, Department of Internal Medicine, Nippon Medical School
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Nodari S, Metra M, Milesi G, Manerba A, Cesana BM, Gheorghiade M, Dei Cas L. The role of n-3 PUFAs in preventing the arrhythmic risk in patients with idiopathic dilated cardiomyopathy. Cardiovasc Drugs Ther 2008; 23:5-15. [PMID: 18982439 DOI: 10.1007/s10557-008-6142-7] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2008] [Accepted: 09/18/2008] [Indexed: 11/29/2022]
Abstract
BACKGROUND N-3 polyunsaturated fatty acids (n-3 PUFAs) intake is associated with a reduction in sudden cardiac death in patients with ischemic heart disease. Their effects in patients with heart failure caused by idiopathic dilated cardiomyopathy (IDC) are unknown. METHODS We compared with placebo the effects of n-3 PUFAs administration in 44 patients with IDC and with frequent or repetitive ventricular arrhythmias at Holter monitoring using a randomized, double-blind design. Arrhythmic risk was assessed by microvolt T-wave analysis (MTWA), signal averaged ECG (SAECG), Holter monitoring, power spectral analysis of heart rate (HR) variability, catecholamine and cytokine plasma levels, at baseline and after 6 months. RESULTS At MTWA, 7/12 patients (58%) initially positive became negative after n-3 PUFAs while one patient became positive after placebo (p = 0.019). N-3 PUFAs administration was also associated to normalization of SAECG (11/15 patients, p < 0.0015), decrease in non-sustained ventricular tachycardia (NSVT) episodes (p = 0.0002) and NSVT HR (p = 0.0003), improvement in HR variability and decrease in catecholamine and cytokine plasma levels. The ratio of plasma n-6 PUFAs to n-3 PUFAs decreased from 12.01 to 3.48 after n-3 PUFAs. CONCLUSIONS N-3 PUFAs administration is associated with favorable effects on parameters related to arrhythmic risk in patients with idiopathic dilated cardiomyopathy. These results are consistent with antiarrhythmic activity independent from their antiischemic effects.
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Affiliation(s)
- Savina Nodari
- Section of Cardiovascular Diseases, Department of Experimental and Applied Medicine, University of Brescia, c/o Spedali Civili, P.zza Spedali Civili, 25100, Brescia, Italy
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Abstract
Sudden cardiac death syndrome remains a major health problem responsible for approximately 400,000 deaths annually in the US. Effective therapies exist but are costly and are associated with potential complications. Currently used strategies for selection of the best candidates for implantable cardioverter defibrillator (ICD) therapy are imperfect and leave a large number of high-risk patients unprotected. At the same time, many patients who received ICDs will never develop tachyarrhythmia and require ICD intervention. The article summarizes the current status and applicability of the noninvasive and invasive tests used for sudden cardiac death risk assessment with the emphasis on the increasingly recognized value of microvolt T wave alternans.
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Affiliation(s)
- S Luke Kusmirek
- Medical University of South Carolina, Charleston, SC 29425, USA
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Yodogawa K, Morita N, Kobayashi Y, Takayama H, Ohara T, Katoh T, Takano T. High-frequency potentials developed in wavelet-transformed electrocardiogram as a novel indicator for detecting Brugada syndrome. Heart Rhythm 2006; 3:1436-44. [PMID: 17161786 DOI: 10.1016/j.hrthm.2006.08.027] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/28/2006] [Accepted: 08/22/2006] [Indexed: 10/24/2022]
Abstract
BACKGROUND A reliable alternative method for detecting Brugada syndrome is desirable because the diagnosis of Brugada syndrome using 12-lead ECG is not optimal. OBJECTIVES The purpose of this study was to assess the usefulness of the wavelet-transformed ECG in detecting Brugada syndrome. METHODS The study consisted of 15 patients with Brugada syndrome and 15 healthy subjects (control group). The parameters on the signal-averaged ECG and the frequency components recorded from the wavelet-transformed ECG were compared between the two groups. Measurements were repeated after pilsicainide infusion in the two groups of patients, after an isoproterenol infusion following pilsicainide injection, and after administration of cilostazol in the group of patients with Brugada syndrome. RESULTS The positive rate of late potentials was 80% in the Brugada syndrome group and 0% in the control group (P <.01). The high-frequency components (80-150 Hz) were developed in the Brugada syndrome group to a greater extent than in the control group, but the low-frequency components (10-50 Hz) did not differ (mean peak power at 80 Hz; 713 +/- 36 vs 488 +/- 60, P <.001). After pilsicainide injection, high-frequency components significantly increased in both groups. However, after isoproterenol and cilostazol administration, high-frequency components significantly decreased but remained higher than in the control group (80 Hz; 655 +/- 40 vs 488 +/- 60, P <.001). The sensitivity of the development of high-frequency components in detecting Brugada syndrome was higher than that of signal-averaged ECG (100% vs 80%), but specificity remained high and similar (100% for both methods). CONCLUSION Abnormally high-frequency components recorded from the wavelet-transformed ECG might be a novel factor in detecting Brugada syndrome.
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Affiliation(s)
- Kenji Yodogawa
- First Department of Internal Medicine, Nippon Medical School, Tokyo, Japan
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Abstract
The wavelet transform has emerged over recent years as a powerful time-frequency analysis and signal coding tool favoured for the interrogation of complex nonstationary signals. Its application to biosignal processing has been at the forefront of these developments where it has been found particularly useful in the study of these, often problematic, signals: none more so than the ECG. In this review, the emerging role of the wavelet transform in the interrogation of the ECG is discussed in detail, where both the continuous and the discrete transform are considered in turn.
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Affiliation(s)
- Paul S Addison
- CardioDigital Ltd, Elvingston Science Centre, East Lothian, UK.
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Engel G, Beckerman JG, Froelicher VF, Yamazaki T, Chen HA, Richardson K, McAuley RJ, Ashley EA, Chun S, Wang PJ. Electrocardiographic arrhythmia risk testing. Curr Probl Cardiol 2004; 29:365-432. [PMID: 15192691 DOI: 10.1016/j.cpcardiol.2004.02.007] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Among the most compelling challenges facing cardiologists today is identification of which patients are at highest risk for sudden death. Automatic implantable cardioverter-defibrillators are now indicated in many of these patients, yet the role of noninvasive risk stratification in classifying patients at high risk is not well defined. The purpose of this review is to evaluate the various electrocardiographic (ECG) techniques that appear to have potential in assessment of risk for arrhythmia. The resting ECG (premature ventricular contractions, QRS duration, damage scores, QT dispersion, and ST segment and T wave abnormalities), T wave alternans, late potentials identified on signal-averaged ECGs, and heart rate variability are explored. Unequivocal evidence to support the widespread use of any single noninvasive technique is lacking; further research in this area is needed. It is likely that a combination of risk evaluation techniques will have the greatest predictive power in enabling identification of patients most likely to benefit from device therapy.
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