Impact of visit-to-visit variability in systolic blood pressure over 5 years and imperceptible atrial conduction: assessment by P-wave signal-averaged electrocardiography.

OBJECTIVE

Visit-to-visit variability in SBP (VVV-SBP) is associated with increased cardiac events, including atrial fibrillation (AF). P-wave signal-averaged electrocardiography (P-SAECG) detects subtle atrial conduction abnormalities such as atrial late potential (ALP). This study examined the association between VVV-SBP and atrial conduction.

METHODS

A total of 128 male participants (mean age: 50.8 ± 10.3 years) with normal cardiac function underwent annual blood pressure measurements over 5 years. VVV-SBP was assessed using both the SD and the coefficient of variation (CV) of SBP, calculated from five BP measurements taken annually during the 5 years prior to the P-SAECG. P-SAECG parameters included the filtered P-wave duration (FPD) and the root-mean-square voltage of the last 20 ms of the P-wave (RMS20). ALP positivity was defined as FPD > 120 ms and RMS20 < 3.5 µV.

RESULTS

ALP positivity was observed in 33 participants (25.8%). SD-SBP was higher in the ALP-positive group (9.59 ± 4.15 vs. 7.92 ± 3.66 mmHg; P  = 0.031). This trend was seen in CV-SBP (ALP-positive; 0.077 ± 0.031 vs. ALP-negative; 0.064 ± 0.027; P  = 0.022). ALP positivity was significantly less frequent in the lowest quartile and more frequent in the highest quartile of both SD-SBP and CV-SBP. In multivariable logistic regression analysis, higher quartiles of both SD-SBP and CV-SBP were independently associated with ALP positivity (e.g. SD-4; P  = 0.014; CV-4; P  = 0.009).

CONCLUSION

Elevated VVV-SBP, assessed by SD and CV, is associated with impaired atrial conduction, highlighting its potential role as a predictor of atrial conduction abnormalities and a tool for AF risk stratification.