The Mechanism Of Electrical Changes In The Right Atrium Of Patients With Sick Sinus Syndrome

Objective To evaluate the characteristic of P wave amplitude from electrocardiogram(ECG),mean voltage of right atria(RA)by 3-D right-atria electroanatomic mapping for sick sinus syndrome(SSS)patients and the relationship behind this phenomenon.Method 20 clinically diagnosed SSS patients were enrolled as patient group and 20 paroxysmal supraventricular tachycardia(PSVT)were enrolled as control group.All patients' P wave amplitude of lead ? and P wave negative amplitude and duration of lead V1 from ECG were measured,then the Ptf-V1 s were calculated.Voltages of right atria by 3-D right-atria electroanatomic mapping were recorded and mean voltage of RA were calculated for both group.Results P wave amplitude of lead ? were 0.11±0.04 m V and 0.14±0.05 mV for SSS group and PSVT group patients.SSS patients' P wave amplitude of lead ? were significantly lower for SSS group patients compared with those for PSVT patients(P=0.0333).There's no significantly differences for Ptf-V1 for both groups(P=0.6594),the mean value were(0.027±0.011)mm·s and(0.025±0.008)mm·s respectively.Mean voltage of RA was(1.3±0.7)mV for SSS group and(2.1±0.5)mV for PSVT group.So there's a significant difference in the mean voltage of RA between the two groups(P=0.0003).Conclusion Compared with normal people,SSS patients had lower RA mean voltage and P wave amplitude could reflect the problem which had clinical implications.