BACKGROUND: The diagnosis of heart failure may be challenging because symptoms are rather nonspecific. Elevated left ventricular (LV) filling pressure may be used to confirm the diagnosis, but cardiac catheterization is often not practical. Echocardiographic indexes are therefore used as markers of filling pressure. OBJECTIVES: This study investigated the feasibility and accuracy of comprehensive echocardiography in identifying patients with elevated LV filling pressure. METHODS: We conducted a multicenter study of 450 patients with a wide spectrum of cardiac diseases referred for cardiac catheterization. Left atrial volume index, in combination with flow velocities and tissue Doppler velocities, was used to estimate LV filling pressure. Invasively measured pressure was used as the gold standard. RESULTS: Mean left ventricular ejection fraction (LVEF) was 47%, with 209 patients having an LVEF <50%. Invasive measurements showed elevated LV filling pressure in 58% of patients. Clinical assessment had an accuracy of 72% in identifying patients with elevated filling pressure, whereas echocardiography had an accuracy of 87% (p < 0.001 vs. clinical assessment). The combination of clinical and echocardiographic assessment was incremental, with a net reclassification improvement of 1.5 versus clinical assessment (p < 0.001). CONCLUSIONS: Echocardiographic assessment of LV filling pressure is feasible and accurate. When combined with clinical data, it leads to a more accurate diagnosis, regardless of LVEF.