Abstract：Objective To explore the correlation between P-wave dispersion (PWD) and heart rate variability (HRV) in subclinical hypothyroidism (SCH) patients with paroxysmal atrial fibrillation (PAF). Methods A total of 71 SCH patients treated by our hospital were enrolled, and they were divided into AF group (37 cases) and control group (34 cases) according to whether they were accompanied with PAF. The maximum P-wave duration (Pmax), the minimum Pwave duration (Pmin) and PWD of 12-lead electrocardiogram (ECG) were measured in the two groups. HRV indexes including SDNN, SDANN, rMSSD, pNN50, LF and HF were compared between the two groups. Results Pmax and PWD of the AF group are significantly higher than those of the control group (P< 0.05). The time domain HRV indexes including SDNN, SDANN, rMSSD and pNN50 of the AF group are significantly lower than those of the control group(P<0.05). The frequency domain HRV indexes including LF and HF of the AF group are both significantly lower than those of the control group (P< 0.05). Pmax and PWD are negatively correlated with HRV indexes(P<0.05). ConclusionP WD significantly increases in SCH patients with PAF, which is closely related to functional dysregulation of cardiac autonomic nerve.
