Section 17

Vascular diseases

The presence of an aortic aneurysm, deep venous thrombosis, or chronic limb-threatening ischemia that is severely symptomatic is the main concern with respect to fitness to drive.

An arterial aneurysm is potentially dangerous if it is expanding and there is a possibility of sudden rupture, which could cause fainting or collapse and loss of vehicle control if the person is driving. Aneurysms occur in the chest, abdomen, pelvis, and extremities and include those related to dissection with or without connective tissue diseases. When completing a medical examination report for a motor vehicle licensing authority, the physician should document maximum aneurysm diameter using an appropriate method. An abdominal ultrasound examination, computed tomography, or magnetic resonance imaging will reliably indicate the size of the aneurysm (Chaikof et al., 2018). Only the anterior–posterior or transverse diameter is predictive of rupture; the length of the aneurysm has no relation to the likelihood of rupture (Filardo et al., 2012). Uncontrolled risk factors such as hypertension may affect rupture rates, although specific data are not available (Sweeting et al., 2012). Ongoing review of the patient is required. A patient with an aortic aneurysm should have the benefit of the opinion of a vascular surgeon. A surgically indicated aortic aneurysm is essentially inconsistent with driving a road vehicle.

The decision to license drivers with aneurysms larger than the currently accepted thresholds for repair should take into consideration aneurysm size and the patient’s comorbid conditions that would influence the risk of repair (Lancaster et al., 2022). In selected cases, the comorbid conditions and the threat of aneurysm rupture based on size (larger than 6 cm in men and 5.5 cm in women) may preclude driving until the aneurysm is repaired (Lederle et al., 2002). A patient in whom surgical repair of their aneurysm is warranted should not drive until the aneurysm is repaired.

Following successful endovascular or open repair of an abdominal aortic aneurysm, the patient may drive once recovered, if no other medical contraindication exists.

Rupture of thoracic and thoracoabdominal aneurysms is also related to aneurysm size, and the threshold for repair is 6 cm. Prospective data comparing early surgery with conservative follow-up are not available. The threshold for repair of thoracic and thoracoabdominal aneurysms is influenced by the size, extent, and location of these aneurysms (Rokosh et al., 2021). Therefore, definitive recommendations for surgery await prospective data; again, however, any aneurysm that warrants surgical intervention is inconsistent with operating a road vehicle.

Chronic limb-threatening ischemia, the most advanced form of atherosclerotic lower limb arterial occlusive disease, can impair the ability to drive because of the severity of limb or foot pain, narcotic intake, or foot mobility. Although prospective data on driving fitness are not available for patients with a condition of this nature, once the disease is successfully treated, a return to driving should be achievable.

Both Raynaud phenomenon and Buerger disease of sufficient severity to cause symptoms require evaluation. These conditions rarely preclude driving unless they cause functional limitations, but ongoing surveillance is required. Those with digital or forefoot amputation related to these conditions may return to regular driving, whereas those with transfemoral or transtibial amputation require appropriate hand controls for driving.

Patients with acute episodes of deep venous thrombosis are at risk of pulmonary embolization. Physicians should advise patients with acute deep venous thrombosis to refrain from driving until the institution of appropriate treatment. At that point, the patient may safely resume driving a motor vehicle.