PR O G RE S S I N C ARDI O V A S CU L A R D I S EA S E S 5 6 (2 0 1 3) 12 5–1 2 6
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Editorial
Ambulatory ECG Monitoring: 50 Years Later This issue of the Journal is dedicated to Prof. Shlomo Stern, who passed away on October 27, 2013. In 1963, 50 years ago, the first commercial Holter monitoring system was released by Bruce Del Mar from Del Mar Avionics (Irvine, CA) who celebrated his centennial in July 2013. He worked in close collaboration with the inventor of the concept and father of the field of telemonitoring and ambulatory ECG monitoring, Dr. Norman J. Holter. In 1988, 25 years ago in Vienna, the International Society for Holter and Noninvasive Electrocardiology (ISHNE) was formally established with Dr. Shlomo Stern as first President. The Society (www.ishne. org) has been successfully serving cardiology and medical communities in advancing science and education of electrocardiology, Holter monitoring, cardiac arrhythmias, and many related fields. This year also marks 30 years of my own involvement in the field. I was honored by Dr. Henry Greenberg, Editor-in-Chief of the Progress in Cardiovascular Diseases, to serve as guest editor for this issue of the Journal to be focused on advances in ambulatory/Holter ECG monitoring. We present a series of articles written by the experts in the field starting with Dr. Harold Kennedy, a pioneer in the clinical application of Holter monitoring, who places this diagnostic method in the historical perspectives of clinical and research use with a clear vision of current and future advances. Holter-detected ventricular arrhythmias have always been of primary interest to physicians who order the test for diagnostic and prognostic purposes. In the current era of implantable defibrillators, Holter-detected, nonsustained ventricular tachycardia episodes play a role in therapeutic decisions, as nicely reviewed by Drs. Katritsis, Siontis, and Camm. To add to these data, our recent analyses from the risk stratification studies indicate that not only presence of nonsustained ventricular tachycardia but also frequent VPBs > 500/24 h are good predictors of subsequent development of ventricular tachycardia or fibrillation requiring ICD treatment. ECG monitoring is a critical tool in managing patients with atrial fibrillation both in diagnosis and in assessment of the effectiveness of treatment. As Drs. Rosero, Kutyifa and colleagues point out, because of rapid advances in technology, monitoring can identify symptomatic, asymptomatic and/or potentially dangerous atrial fibrillation episodes, determine
ventricular response, and provide actionable data to guide clinical decision-making rapidly and accurately. Heart rate variability, providing a window into the autonomic regulation of the heart, is an established risk marker for predicting mortality after myocardial infarction and in heart failure patients. Drs. Huikuri and Stein very elegantly present clinical and methodological aspects of heart rate variability. Heart rate turbulence, described in this issue by Dr. Cygankiewicz, is an attractive risk stratifier since it learns from heart rate behavior challenged by ventricular premature beats. Despite about 25 years of research use of heart rate variability and almost 15 years for the heart rate turbulence their clinical applicability needs to be validated in clinical trials so that therapeutic decisions can be driven by the results of these tests. Research on dynamics of repolarization in Holter recordings also is very promising. Dr. Verrier and Ikeda summarize for us the state-of-the-art knowledge regarding ambulatory ECGbased T-wave alternans monitoring with specific emphasis on electrophysiologic mechanisms underlying T-wave alternans, methodological aspects, and clinical evidence supporting its use in risk stratification. Since repolarization dynamics will not always demonstrate an alternans pattern, it is important to assess beat-to-beat variation in QT duration or repolarization morphology. Drs. Dobson, Kim, and Haigney provide us with a very comprehensive overview of current advances in the field of QT variability (or lability) with appropriate caution that more studies are needed to determine whether this method, as well as T-wave alternans, can contribute to therapeutic decisions. Ambulatory ECG monitoring is an effective tool for assessing the frequency and duration of silent ischemic episodes. In addition to its diagnostic value, ischemia monitoring in the current age of primary coronary interventions should focus more on assessing anti-ischemic (revascularization or drug) therapies, as pointed out by Drs. Wimmer, Scirica, and Stone. Evaluation of patients with syncope has always included ECG monitoring but recent advances in technology of monitoring, summarized here by Dr. Ruwald, with significantly prolonged duration of monitoring (including implantable loop recorders) and more sophisticated detection of rhythm abnormalities, open truly effective ways to help in diagnostic process of unexplained syncope. Dr. Ritter’s paper is the perfect illustration of how technologies of long-term ECG monitoring and implanted
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devices (pacemaker and defibrillators) can merge, becoming extremely effective tools for monitoring function of devices or identification of cardiac arrhythmias. An addition of remote monitoring to these more and more sophisticated devices (tracking body motion, heart rate variability, ST segment) makes this concept extremely useful clinically. ECG patch monitoring devices, described by Dr. Lobodzinski, are a glimpse of the future of ECG monitoring when small skin-attached disposable electrode-like devices track heart rhythm and its abnormalities with a possibility of automatic transmission via internet technologies. We are very thankful to all contributors to this issue for their insightful presentations that will serve our readers well, keeping them up-to-date with advances in ambulatory ECG
monitoring. We believe that the future of ambulatory monitoring that started 50 years ago is very bright with every cell phone and broad band internet access likely to enhance our monitoring capabilities. Wojciech Zareba Cardiology Division University of Rochester Medical Center Rochester, NY [email protected] 0033-0620/$ – see front matter © 2013 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.pcad.2013.09.017
Available online at www.sciencedirect.com
ScienceDirect www.onlinepcd.com
Editorial
Ambulatory ECG Monitoring: 50 Years Later This issue of the Journal is dedicated to Prof. Shlomo Stern, who passed away on October 27, 2013. In 1963, 50 years ago, the first commercial Holter monitoring system was released by Bruce Del Mar from Del Mar Avionics (Irvine, CA) who celebrated his centennial in July 2013. He worked in close collaboration with the inventor of the concept and father of the field of telemonitoring and ambulatory ECG monitoring, Dr. Norman J. Holter. In 1988, 25 years ago in Vienna, the International Society for Holter and Noninvasive Electrocardiology (ISHNE) was formally established with Dr. Shlomo Stern as first President. The Society (www.ishne. org) has been successfully serving cardiology and medical communities in advancing science and education of electrocardiology, Holter monitoring, cardiac arrhythmias, and many related fields. This year also marks 30 years of my own involvement in the field. I was honored by Dr. Henry Greenberg, Editor-in-Chief of the Progress in Cardiovascular Diseases, to serve as guest editor for this issue of the Journal to be focused on advances in ambulatory/Holter ECG monitoring. We present a series of articles written by the experts in the field starting with Dr. Harold Kennedy, a pioneer in the clinical application of Holter monitoring, who places this diagnostic method in the historical perspectives of clinical and research use with a clear vision of current and future advances. Holter-detected ventricular arrhythmias have always been of primary interest to physicians who order the test for diagnostic and prognostic purposes. In the current era of implantable defibrillators, Holter-detected, nonsustained ventricular tachycardia episodes play a role in therapeutic decisions, as nicely reviewed by Drs. Katritsis, Siontis, and Camm. To add to these data, our recent analyses from the risk stratification studies indicate that not only presence of nonsustained ventricular tachycardia but also frequent VPBs > 500/24 h are good predictors of subsequent development of ventricular tachycardia or fibrillation requiring ICD treatment. ECG monitoring is a critical tool in managing patients with atrial fibrillation both in diagnosis and in assessment of the effectiveness of treatment. As Drs. Rosero, Kutyifa and colleagues point out, because of rapid advances in technology, monitoring can identify symptomatic, asymptomatic and/or potentially dangerous atrial fibrillation episodes, determine
ventricular response, and provide actionable data to guide clinical decision-making rapidly and accurately. Heart rate variability, providing a window into the autonomic regulation of the heart, is an established risk marker for predicting mortality after myocardial infarction and in heart failure patients. Drs. Huikuri and Stein very elegantly present clinical and methodological aspects of heart rate variability. Heart rate turbulence, described in this issue by Dr. Cygankiewicz, is an attractive risk stratifier since it learns from heart rate behavior challenged by ventricular premature beats. Despite about 25 years of research use of heart rate variability and almost 15 years for the heart rate turbulence their clinical applicability needs to be validated in clinical trials so that therapeutic decisions can be driven by the results of these tests. Research on dynamics of repolarization in Holter recordings also is very promising. Dr. Verrier and Ikeda summarize for us the state-of-the-art knowledge regarding ambulatory ECGbased T-wave alternans monitoring with specific emphasis on electrophysiologic mechanisms underlying T-wave alternans, methodological aspects, and clinical evidence supporting its use in risk stratification. Since repolarization dynamics will not always demonstrate an alternans pattern, it is important to assess beat-to-beat variation in QT duration or repolarization morphology. Drs. Dobson, Kim, and Haigney provide us with a very comprehensive overview of current advances in the field of QT variability (or lability) with appropriate caution that more studies are needed to determine whether this method, as well as T-wave alternans, can contribute to therapeutic decisions. Ambulatory ECG monitoring is an effective tool for assessing the frequency and duration of silent ischemic episodes. In addition to its diagnostic value, ischemia monitoring in the current age of primary coronary interventions should focus more on assessing anti-ischemic (revascularization or drug) therapies, as pointed out by Drs. Wimmer, Scirica, and Stone. Evaluation of patients with syncope has always included ECG monitoring but recent advances in technology of monitoring, summarized here by Dr. Ruwald, with significantly prolonged duration of monitoring (including implantable loop recorders) and more sophisticated detection of rhythm abnormalities, open truly effective ways to help in diagnostic process of unexplained syncope. Dr. Ritter’s paper is the perfect illustration of how technologies of long-term ECG monitoring and implanted
126
PR O GRE S S I N C ARDI O VAS CU L AR D I S EAS E S 5 6 ( 2 0 13 ) 12 5–1 26
devices (pacemaker and defibrillators) can merge, becoming extremely effective tools for monitoring function of devices or identification of cardiac arrhythmias. An addition of remote monitoring to these more and more sophisticated devices (tracking body motion, heart rate variability, ST segment) makes this concept extremely useful clinically. ECG patch monitoring devices, described by Dr. Lobodzinski, are a glimpse of the future of ECG monitoring when small skin-attached disposable electrode-like devices track heart rhythm and its abnormalities with a possibility of automatic transmission via internet technologies. We are very thankful to all contributors to this issue for their insightful presentations that will serve our readers well, keeping them up-to-date with advances in ambulatory ECG
monitoring. We believe that the future of ambulatory monitoring that started 50 years ago is very bright with every cell phone and broad band internet access likely to enhance our monitoring capabilities. Wojciech Zareba Cardiology Division University of Rochester Medical Center Rochester, NY [email protected] 0033-0620/$ – see front matter © 2013 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.pcad.2013.09.017
