What is the gold standard for the diagnosis of HFpEF?

• A. Exercise PCWP during supine bicycling with VO2 monitoring and right heart catheterization
• B. Resting PCWP measured at baseline conditions
• C. Echocardiography alone
• D. Cardiac MRI at rest

Answer: (A)

Diagnosing HFpEF relies on demonstrating elevated left-sided filling pressures during exertion, because symptoms typically appear with activity even when the ejection fraction is preserved. The most definitive way to prove this is through invasive hemodynamic testing during exercise: right heart catheterization with supine bicycling and simultaneous VO2 monitoring to measure the pulmonary capillary wedge pressure as the patient exercises. This directly shows how filling pressures rise with increased demand, which is the hallmark of HFpEF.

Resting measurements can miss the problem, since filling pressures may be normal at rest despite abnormal diastolic reserve. Echocardiography and other imaging can assess structure and some function, but they cannot confirm abnormal filling pressures during exercise on their own. Cardiac MRI at rest provides anatomy and function but not the dynamic, exercise-induced hemodynamic response. Hence, exercise PCWP measured invasively is the gold standard for establishing HFpEF.