Narrow pulse pressure

An abnormally small difference between systolic and diastolic arterial blood pressures (<40 mmHg difference or ≤25% of the systolic pressure), reflecting reduced stroke volume or diminished cardiac output. Possible causes are hypovolemia (hemorrhage, dehydration, shock), heart failure, aortic stenosis, cardiac tamponade, or increased intrathoracic pressure (tension pneumothorax or COPD).