The study aimed to identify early echocardiographic and circulating biomarkers of heart failure (HF) in hypertensive patients with normal resting echocardiography. Echocardiography at rest and during exercise, and selected biomarkers were assessed in control group, dyspnea group, and HF group. On exercise dyspnea patients had lower early diastolic (E') and systolic (S') mitral annular velocity (12.8 ± 1.0 vs 14.9 ± 3.0 cm/sec and 9.3 ± 2.0 vs 10.9 ± 2.0 cm/sec, respectively), and higher E/E' ratio compared to control group (6.7 ± 1.0 vs 5.9 ± 1.0) (p < 0.05 for all comparisons). The level of N-terminal propeptide of procollagen type III (PIIINP) was significantly higher in dyspnea group than in controls (p = 0.01). Control and dyspnea patients had lower levels of cardiotrophin-1, cystatin C, syndecan-4, and N terminal-probrain natriuretic peptide than HF patients (all p ≤0.01). In multivariate analysis PIIINP (unadjusted odds ratio [OR] = 8.2, 95% confidence interval [Cl] 1.7-40.6; p = 0.001; adjusted OR = 8.7; 95%CI: 1.5-48.3; p = 0.001) and E/E' ratio on exercise (unadjusted OR = 1.8, 95%CI: 0.8-4.0; p = 0.033; adjusted OR = 2.0; 95%CI: 0.8-4.8; p = 0.012) were the only factors significantly associated with the presence of dyspnea. PIIINP is the first early biomarker for the HF development in patients with HA and normal resting echocardiography. Exertional echocardiography may indicate patients with incipient HF with preserved ejection fraction.