Impact of Peripheral Vascular Resistance Reduction on Diastolic Blood Pressure

Fundamental Hemodynamic Relationship

Blood pressure fundamentally depends on cardiac output and peripheral vascular resistance, as stated by the European Society of Cardiology 1

Peripheral vascular resistance decreases during dynamic exercise through vasodilation in working muscles, causing diastolic blood pressure to remain unchanged or decrease slightly, according to the American Heart Association 2, 3
This reduction in peripheral vascular resistance results in a normal response of stable or slightly decreased diastolic blood pressure during exercise, as reported by the American College of Cardiology 2, 3, 4
Systolic pressure rises progressively with exercise intensity, while diastolic pressure stays stable or drops modestly, as observed by the American Heart Association 3, 4
The resulting widening of pulse pressure during exercise reflects the combination of increased systolic pressure and maintained or reduced diastolic pressure, as described by the European Society of Cardiology 2

Acute administration of vasodilators reduces peripheral vascular resistance and results in decreased diastolic blood pressure, as stated by the American College of Cardiology 5, 6

In pediatric septic shock, vasodilator therapy reduces afterload, increases vascular capacitance, and allows volume loading to restore cardiac output at lower filling pressures, as recommended by the Society of Critical Care Medicine 7
This approach decreases heart rate and improves perfusion by reducing the elevated peripheral vascular resistance that was maintaining diastolic pressure, according to the American College of Cardiology 7

High cardiac output states require lowered systemic vascular resistance through peripheral arterial vasodilation to maintain normal systemic blood pressure, as reported by the American Heart Association 8
This leads to wide pulse pressures and low diastolic blood pressure as a compensatory mechanism, as described by the European Society of Cardiology 8

Mean arterial pressure depends on both cardiac output and peripheral vascular resistance, so isolated peripheral vascular resistance reduction may not always lower diastolic pressure if cardiac output increases sufficiently, as stated by the Society of Critical Care Medicine 7
Excessive reduction in diastolic pressure can compromise myocardial perfusion, as warned by the American College of Cardiology 7
When diastolic blood pressure falls too low with high heart rates, inadequate time for coronary filling can reduce contractility and cardiac output, as reported by the Society of Critical Care Medicine 7