Grubb.qxp 16/7/08 02:12 Page 26
Cardiac Monitoring
Implantable Cardioverter–Defibrillators and Driving—Current Perspectives
a report by
Blair P Grubb, MD
1
and Naser Imran, MD
2
1. Professor of Medicine and Pediatrics; 2. Fellow, Cardiovascular Medicine, College of Medicine, Health Science Campus, University of Toledo
Perhaps one of the most important developments in modern cardiovascular important being the ability to continue an active lifestyle, which may involve
medicine was the development of the implantable cardioverter–defibrillator the ability to safely drive a motor vehicle.
(ICD) in the early 1980s. This development has revolutionized the
management of patients who have experienced or are at risk for lethal While drug treatment of arrhythmias (at least in theory) prevented or
cardiac arrhythmias. These remarkable devices fulfilled a long-held dream of reduced episodes of VT and VF leading to sudden cardiac death, the ICD
being able to effectively recognize and terminate life-threatening ventricular could terminate an episode only once it had already occurred. Loss of
arrhythmias using a small surgically implanted device. consciousness (or even a lapse in orientation) while driving could potentially
have devastating consequences. Thus, it was generally felt that driving by
The overwhelming majority of recipients of the first ICDs were survivors of patients who had an ICD should be restricted so as to avoid possible injury
sudden cardiac death. With the advent of ICDs, there was a significant to either themselves or others. Patients with ICDs were required to wait at
reduction in the rates of death secondary to ventricular tachycardia (VT) or least six months before being allowed to drive as it was felt that the risk of
ventricular fibrillation (VF). The use of ICDs effectively transformed sudden recurrence of VT or VF gradually diminished over time to an acceptable level
death into a chronic illness. Since then, indications for the implantation of at six months. Over the years, in addition to the expansion in indications for
ICDs have broadened to include primary prophylaxis for patients deemed to implantation there have been advances in ICD technology, as well as the
be at a high risk for sudden cardiac death due to hereditary and congenital publication of long-term observational studies that have allowed us to risk-
conditions such as long QT syndrome, Brugada syndrome, and stratify various patient cohorts. The dependence on motor vehicles for
arrhythmogenic right ventricular dysplasia. With the publication of day-to-day activities has also increased dramatically. These advances in
landmark studies such as the Multicenter Automatic Defibrillator technology and lifestyle changes have forced both patients and physicians
Implantation Trial (MADIT)-I and -II and the Sudden Cardiac Death in Heart to re-address the issue of driving restrictions.
Failure Trial (SCD-HeFT), over the last few years guidelines from
expert panels have also recommended ICD implantation for patients with By today’s standards, the original devices were simplistic: they usually
low ejection fractions secondary to ischemic and non-ischemic required up to 15 seconds to detect, charge, and shock a potentially lethal
cardiomyopathies. The huge expansion in the number of potential arrhythmia. In addition, the early ICDs lacked the ability to provide back-up
candidates requiring ICD implantation has given rise to an increasing pacing. Given these limitations, it was not unusual for a patient to have a
interest in the practical ramifications of this therapy—one of the most near-syncopal or syncopal episode when experiencing an ICD discharge.
Since their original development over 20 years ago, ICD technology has
evolved significantly. Devices are now placed transvenously without the
Blair P Grubb, MD, is a Professor of Medicine and Pediatrics at
the University of Toledo, Health Science Campus, where he is
need for extensive surgical procedures, are programmable, and incorporate
also Director of the Electrophysiology Program at the University features such as biphasic waveforms, back-up and anti-tachycardiac pacing,
Medical Center. He has been recognized as one of ‘America’s Top
enhanced arrhythmia recognition, and much faster charge times. These
Doctors’ for three years in a row and is widely considered one of
the world’s leading authorities on syncope and disorders of the
developments have made placement comparatively easy and have markedly
autonomic nervous system. Professor Grubb has authored over improved their effectiveness and efficiency in detecting and terminating
170 scientific papers, two books, and 31 book chapters. He
tachyarrhythmias. These enhancements have facilitated the expansion of
received his MD from the Universidad Central del Este in the
Dominican Republic and completed his residency training at the
the use of ICDs from sudden death survivors to prophylactic placement
Greater Baltimore Medical Center. in individuals who are at a high risk for sudden death.
E:
blair.grubb@utoledo.edu
This rapid expansion of ICD use has led to renewed interest in the issue of
Naser Imran, MD, is a Fellow in Cardiovascular Medicine at
driving by patients who have received an ICD. Expert panels that were
the University of Toledo Medical Center. His interests lie in
clinical cardiac electrophysiology and the pathophysiology of
convened to address the issue initially suggested that a patient who
supraventricular arrhyhmias. Dr Imran is a graduate of the Dow had received an ICD after surviving an episode of sudden death (or a
Medical College, Karachi, and is a Member of the Royal College
patient who had received an ICD shock for an episode of VT or
of Physicians and the Royal College of Physicians of Ireland.
fibrillation) should not drive for a period of at least six months after
implantation.
1
The basis for this recommendation was the observation
that the likelihood of experiencing another event could be represented by
26 © TOUCH BRIEFINGS 2008
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76 |
Page 77 |
Page 78 |
Page 79 |
Page 80 |
Page 81 |
Page 82 |
Page 83 |
Page 84