What is the relationship between aortic regurgitation and increased pulse volume (pulse pressure)?

From the Guidelines

Aortic regurgitation is characterized by a widened pulse pressure with a bounding, collapsing pulse known as a water-hammer or Corrigan's pulse, which is a result of the increased stroke volume and subsequent regurgitation of blood into the left ventricle during diastole. This occurs because blood flows backward into the left ventricle during diastole, leading to increased stroke volume during the next systole. The increased forward stroke volume creates a higher systolic pressure, while the regurgitation causes a lower diastolic pressure, thus widening the pulse pressure. Clinically, this manifests as a rapidly rising and falling pulse that can be felt as a forceful, quick collapse when palpating peripheral arteries, particularly the radial artery. Other characteristic findings include visible pulsations in the neck (Corrigan's sign), bobbing of the head with each heartbeat (de Musset's sign), and capillary pulsations in the nail beds (Quincke's pulse). The severity of these pulse abnormalities generally correlates with the degree of regurgitation, as outlined in the 2020 ACC/AHA guideline for the management of patients with valvular heart disease 1.

According to the guideline, severe AR is associated with a wide pulse pressure, such that systolic blood pressure is higher than in patients without AR even when systemic vascular resistance is normal 1. The management of patients with AR depends on an accurate diagnosis of the disease, which can be achieved through the assessment of valve anatomy, valve hemodynamics, and hemodynamic consequences, as well as the presence of symptoms. The guideline provides a classification system for chronic AR, which includes four stages: at risk of AR, progressive AR, asymptomatic severe AR, and symptomatic severe AR. Each stage has distinct characteristics, including valve anatomy, valve hemodynamics, and hemodynamic consequences, which can guide treatment decisions.

Key characteristics of each stage include:

• Stage A: at risk of AR, with no or trace AR severity
• Stage B: progressive AR, with mild to moderate AR severity
• Stage C: asymptomatic severe AR, with severe AR severity and normal or abnormal LV systolic function
• Stage D: symptomatic severe AR, with severe AR severity and symptoms. The assessment of pulse volume and character is crucial in the diagnosis and management of aortic regurgitation, as it can provide valuable information about the severity of the disease and guide treatment decisions. The use of medications such as beta blockers and vasodilating drugs, such as ACE inhibitors or ARBs, can also affect pulse pressure and should be considered in the management of patients with AR, as recommended by the guideline 1.

From the Research

Aortic Regurgitation and Pulse Volume

• Aortic regurgitation (AR) is a valvular heart disease characterized by retrograde blood flow from the aorta to the left ventricle 2.
• The disease progression of AR is influenced by left ventricular (LV) mechanics and aortic impedance, which are the main determinants of outcome in patients with AR 3.
• In chronic AR, medical management aims to control hypertension and delay left ventricular dysfunction, with angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, and potentially calcium-channel blockers recommended for treatment 2.
• The relationship between aortic regurgitation and pulse volume is not directly addressed in the provided studies, but it is known that AR can lead to increased pulse pressure and volume due to the retrograde flow of blood into the left ventricle 4, 5.
• Exercise testing can help highlight symptoms related to valve dysfunction in patients with AR, and asymptomatic patients with severe AR and preserved LV function can benefit from vasodilator drug therapy 3, 4.

Management of Aortic Regurgitation

• Surgical aortic valve replacement is the predominant treatment for AR, but its use is limited to patients with an acceptable surgical risk profile 6.
• Transcatheter aortic valve implantation is an alternative treatment for AR, but further data and experience are required to fully understand its benefits and limitations 6.
• Medical treatment with vasodilators and anti-remodeling drugs can be helpful in some patients with AR, but should not replace or delay aortic valve surgery when indicated 5.

Diagnosis and Treatment Guidelines

• Diagnosis of AR relies on electrocardiography, chest radiographs, and echocardiography, with cardiac magnetic resonance imaging potentially incorporated in chronic AR diagnosis 2.
• Clinical evaluation and serial imaging tests can optimize the timing for intervention in patients with AR, with the goal of preventing unnecessary surgical risks while also avoiding delayed intervention 5.