Abstract: Objective To observe the frequency of fragmented QRS in high altitude polycythemia (HAPC) and influencing factors. Methods A cross-sectional analysis was performed in Qinghai Provincial People’s Hospital.From June.2017 to March.2018, 328 patients with HAPC were enrolled in our study, 303 patients without HAPC were as control. The age, height, weight, surface 12 lead ECG, RBC, Hb, Hct were analyzed. Results The fQRS incidence was higher in HAPC compared to control group, the differences were significant (P<0.001). Logistic regression analysis showed that Hb was the independent risk factor of fQRS. Conclusions fQRS prevalence is related to Hb levels in patients with HAPC.

Key words: high altitude polycythemia (HAPC), fragmented QRS, relationship