EXERCISE ECHOCARDIOGRAPHY OR CARDIOPULMONARY EXERCISE TEST TO DETECT HEART FAILURE WITH PRESERVED EJECTION FRACTION?

Objective: Diagnosis of heart failure with preserved ejection fraction (HFpEF) is complex, especially in its earlier, pre-clinical stage. Stress tests have been suggested as possible tools to improve the diagnosis of HFpEF, albeit with contrasting and debated evidences. We sought to evaluate the diagnostic performance of stress tests in consecutive ambulatory patients evaluated for exertional breathlessness. Design and method: Retrospective analysis of data in patients with unexplained dyspnea who underwent 1) echocardiography at rest and 2) exercise echo combined with cardiopulmonary exercise test (CPET). Diastolic function at rest and at exercise was scored according to 2016 ASE/EACVI criteria. Exercise oscillatory ventilation (EOV+) was chosen as a CPET marker of high filling pressure during effort. Diagnosis of HFpEF was established by a right heart catheterization (RHC) demonstrating a pulmonary artery wedge pressure (PAWP) > 15 mmHg at rest and/or a PAWP>=25 mmHg at peak exercise. Results: 72 patients in sinus rhythm with normal left ventricular ejection fraction (68+/-10 years old, 68% females, BMI 27+/-5 Kg/m2) were evaluated. At rest, 82% of patients had either normal diastolic function or grade I diastolic dysfunction or indeterminate diastolic function, while 18% had estimation of high filling pressure (figure 1). Exercise stress echo was positive in 5 cases (7%), while diastolic function during effort resulted “indeterminate” in 93% of patients. EOV+ was found in 15 cases (21%), i.e. in 4/5 patients with positive exercise echocardiography and in 11/67 with indeterminate diastolic function at exercise. Twenty patients (26%) underwent RHC as clinically indicated, including 19 RHC during exercise (figure 1). RHC revealed HFpEF in 17 cases (85%). Both exercise echo and EOV+ at CPET had a 100% specificity and positive predictive value to noninvasively detect HFpEF. However, sensitivity of exercise echo was only 13%, compared with 53% of EOV+ at CPET (p < 0.05).Conclusions: Our preliminary results: confirm the limitations of echocardiography for the diagnosis of HFpEF; suggest that EOV+ at CPET may have higher sensitivity than exercise echocardiography for the noninvasive detection of HFpEF, maintaining an excellent specificity.