Recent therapeutic advances for patients with life-threatening ventricular arrhythmias and the cardiac conditions which underlie them have resulted in more patients living longer lives in spite of the presence of severe disease. In addition, these therapeutic advances have allowed these same patients to continue functioning at very high levels, returning to work and resuming vigorous physical lifestyles.

For patients with life-threatening arrhythmias like ventricular tachycardia and ventricular fibrillation, the implantable cardioverter defibrillator (ICD) represents once such technologic advance. While the ICD has been proven to improve survival in these patients, it does not prevent the occurrence of arrhythmias nor does it necessarily prevent the loss of consciousness often associated with the arrhythmia.

Given these factors, the physician is often asked to offer recommendations to patients regarding the safety and timing of their return to specific activities. For physicians treating patients with life-threatening arrhythmias, the most commonly asked question is "When can I start driving?" Weighing the risks of potential loss of consciousness against the social debilitation that the loss of driving creates for patients makes the question even more complex. This issue of The Arrhythmia News will discuss the information available and offer a rational approach to the difficult problem of driving in the ICD patient.

Facts: It is important to note that it is the underlying medical condition (ventricular arrhythmias) that confers risk associated with driving and not the form of therapy (ICD). Antiarrhythmic medications do not eliminate the risk of recurrent ventricular arrhythmia or syncope; any discussion of driving and ICD patients applies to patients on antiarrhythmic medications as well.

Little hard data exists regarding driving in ICD patients in part because the long-standing practice was recommendation to not drive. Despite those recommendations, some patients did drive. Interestingly, one small study presented several patients who received shocks while driving; only one was involved in a serious accident. The most thorough evaluation of risk comes from Canada (see reference below). This study developed an equation based on known arrhythmia risk data. It calculated a risk of motor vehicle accidents not significantly different from other groups in whom driving restriction is not prescribed (e.g., cardiac patients, teenage or elderly drivers, etc.). Interestingly, one of the most important factors regarding risk was "time behind the wheel", suggesting that long trips, high speed and commercial driving be avoided.

Legal and Liability Issues: In the US, motor vehicle operation is regulated by the states. At present, no regulations limiting driving or requiring physician reporting of patients with ventricular arrhythmias exist in the tri-state region (NY, NJ, CT). In contradistinction, strict regulations exist for patients with seizure disorders in almost all states. For comparison, the piloting of commercial and private aircraft in the US is under the regulation of a single body, the Federal Aviation Administration. Piloting is strictly prohibited. As awareness and information regarding ventricular arrhythmias become more widespread, future state regulation seems likely.

Liability issues are raised should an accident result from a driverís arrhythmia. Concern over physician liability has kept physicians from allowing many patients to return to driving. In an attempt to protect against this potential liability and to influence future legislation, national groups like the AHA and NASPE are formulating physician guidelines. Initial attempts have been promising (see reference) and efforts are ongoing.

Recommendations of the Arrhythmia Service:

1. A history of recurrent syncopal ventricular arrhythmia should preclude a return to driving. Since arrhythmias are most likely to occur early after an initial event, a waiting period of at least three to six months seems indicated for these patients to establish patterns of symptomatic events. Absent or infrequent events during this period may suggest a somewhat reduced risk and a loosening of driving restriction.
2. Clearly, commercial driving or piloting aircraft is prohibited. Long drives (i.e. cross country) even in private driving should be prohibited.
3. Recurrent ventricular arrhythmias clearly not associated with loss of consciousness need not preclude patients from driving. The patientís reaction to an ICD shock must also be considered. A waiting period, perhaps until follow-up testing of the ICD at 1-2 months post-implant, may be prudent to establish the frequency of arrhythmias and to confirm the patient response to arrhythmia and therapy (shock).
4. Therapy must be individualized for each patient.