Exercise Testing and Stress Imaging in Aortic Valve Disease.

Area of Science:

• Cardiology
• Cardiac Surgery
• Diagnostic Imaging

Background:

• Aortic stenosis (AS) is a growing cardiac pathology where aortic valve replacement (AVR) is the only proven survival benefit for symptomatic patients.
• The benefit of prophylactic AVR in asymptomatic patients remains unproven, and prognosis worsens significantly once symptoms develop.

Purpose of the Study:

• To evaluate the role of exercise testing and exercise stress echocardiography in risk stratification and management of asymptomatic patients with severe aortic valve disease.
• To determine the utility of these non-invasive tests in identifying patients who may benefit from AVR and guiding watchful waiting strategies.

Main Methods:

• Exercise testing to unmask "pseudo-asymptomatic" patients and link dyspnea to aortic valve disease.
• Exercise stress echocardiography and cardiopulmonary exercise testing for cases where exercise testing is inconclusive.
• Analysis of exercise-induced changes in left ventricular ejection fraction (LVEF) and pulmonary hypertension for risk stratification.

Main Results:

• Exercise testing can identify "pseudo-asymptomatic" patients and facilitate a "watchful waiting strategy" for those with unrelated dyspnea.
• An increase in mean aortic valve pressure gradient >18-20 mmHg during exercise indicates increased cardiac event risk in severe AS.
• Exercise-induced decrease in LVEF by 5% may predict LV systolic dysfunction post-AVR in asymptomatic or minimally symptomatic patients.

Conclusions:

• Exercise testing and exercise echocardiography are safe and provide valuable clinical information for risk assessment in asymptomatic aortic disease patients.
• These tests are encouraged, especially in heart valve clinics, to aid in the management of complex cases and optimize treatment decisions.