Co-variation between walking ability and circulatory alterations in patients with intermittent claudication

Area of Science:

• Vascular Medicine
• Exercise Physiology

Background:

• Intermittent claudication, characterized by leg pain during exercise, often stems from peripheral arterial disease.
• Unselected patients with subjective symptoms require evaluation to understand circulatory limitations.

Purpose of the Study:

• To assess if central or peripheral circulation limits walking capacity in patients with intermittent claudication.
• To determine the relationship between maximum walking capacity and hemodynamic measures.
• To compare information from treadmill and bicycle ergometer tests on maximum performance.

Main Methods:

• Clinical examination and circulatory tests (calf blood-flow, ankle/toe pressures) in 183 patients.
• Assessment of maximum walking capacity using treadmill and bicycle ergometer tests.
• Calculation of ankle/brachial blood pressure index and post-ischemic calf blood-flow.

Main Results:

• Leg arterial insufficiency limited walking capacity in 90% of patients on a treadmill (282m).
• Leg exhaustion limited performance in 80% during bicycle ergometry (84W).
• Ankle/brachial index showed a weak correlation (r=0.30) with walking capacity.

Conclusions:

• Peripheral circulation is the primary limitation for walking capacity in most patients with intermittent claudication.
• Treadmill walking capacity aligns with bicycle ergometer exercise capacity.
• Standard hemodynamic measures have limited predictive value for walking capacity.