From the Guidelines
Pulse pressure is primarily influenced by conditions that affect stroke volume or arterial stiffness, with wide pulse pressure (greater than 60 mmHg) caused by conditions such as aortic regurgitation, arterial stiffness, and high cardiac output states, and narrow pulse pressure (less than 40 mmHg) resulting from conditions that decrease stroke volume or increase peripheral resistance, such as cardiac tamponade and severe aortic stenosis. The main causes of wide pulse pressure include:
- Aortic regurgitation, where blood flows backward into the left ventricle during diastole 1
- Arterial stiffness from aging or atherosclerosis
- High cardiac output states like fever, anemia, hyperthyroidism, and pregnancy
- Patent ductus arteriosus
- Severe aortic insufficiency On the other hand, narrow pulse pressure results from conditions that decrease stroke volume or increase peripheral resistance, including:
- Cardiac tamponade, where fluid accumulation around the heart restricts filling
- Constrictive pericarditis
- Severe aortic stenosis, which obstructs left ventricular outflow
- Cardiogenic shock
- Hypovolemic states from blood loss or dehydration A recent study published in 2024 found that in patients with peripheral cannulation, a narrow pulse pressure from the right radial arterial line suggests a mixing point proximal to the innominate artery, whereas a wide pulse pressure due to LV ejection indicates the mixing point is more distal 1. Pulse pressure assessment provides valuable clinical information about cardiovascular function, with extreme values often indicating significant pathology requiring prompt evaluation and management.
From the Research
Causes of Wide Pulse Pressure
- Wide pulse pressure is associated with hyperdynamic circulation and high-output heart failure, such as aortic regurgitation and hyperthyroidism 2
- Arteriosclerosis and diffuse vascular stiffening due to aging can also lead to increased pulse pressure 2
- Wide pulse pressure can be a sign of deteriorating cardiovascular health and carries increased risk for mortality, disease progression, and adverse clinical outcomes in chronic diseases including cardiovascular disease and chronic kidney disease 2
- Antihypertensive medication class can also affect pulse pressure, with diuretics alone or in combination with beta-blockers showing lower mean pulse pressure in older hypertensive subjects 3
- Wide pulse pressure has been associated with poor coronary collateral flow in patients with ST-elevation myocardial infarction undergoing percutaneous coronary intervention 4
Causes of Narrow Pulse Pressure
- Narrow pulse pressure is a sign of Class-II hemorrhage and is independently associated with massive transfusion and emergent surgery in hemodynamically stable trauma patients 5
- Narrow pulse pressure has been linked to higher mortality, longer hospital stay, and ICU stay in trauma patients 5
- The clinical significance of narrow pulse pressure is still being researched, but it may be related to left ventricular traits and adverse outcomes in patients with heart failure with preserved ejection fraction 6