Association between inter-leg blood pressure difference and cardiovascular outcome in patients undergoing percutaneous coronary intervention

Abstract

Background: Although the inter-arm blood pressure (BP) difference has been advocated to be associated with cardiovascular events, the implication of inter-leg BP difference has not been well established. This study was conducted to investigate whether inter-arm and -leg BP differences have prognostic value in patients undergoing percutaneous coronary intervention (PCI).

Methods: In this prospective study, we consecutively enrolled 667 patients who underwent PCI. Both arm and leg BPs were measured at the day after PCI. The primary outcome was a major adverse cardiovascular event (MACE) including cardiac death, acute coronary syndrome, coronary revascularization, stroke, and hospitalization for heart failure during the follow-up period.

Results: Mean age was 64.0±11.1 years old, and males were predominant (70.5%). During a mean follow-up period of 3.0 years, MACE occurred in 209 (31.3%) patients. The inter-leg systolic BP difference (ILSBPD) was significantly higher in patients with MACE than those without (9.9±12.3 vs. 7.2±7.5 mmHg, P = 0.004). The inter-arm systolic BP difference was not significantly different between patients with and without MACE (P = 0.403). In multivariable Cox regression analysis, increased ILSBPD was independently associated with the development of MACE (per 5 mmHg; hazard ratio, 1.07; 95% confidence interval, 1.01-1.14). The inter-arm systolic BP difference was not associated with MACE in the multivariable analysis.

Conclusion: Increased ILSBPD was independently associated with worse cardiovascular outcomes after PCI. As ILSBPD is easy to measure, it may be helpful in the risk stratification of patients undergoing PCI.

Fig 1. Kaplan-Meier curves for MACE and risk of MACE according to ILSBPD.

The curves for survival from MACE are presented according to ILSBPD (<16 vs. ≥16 mmHg). Abbreviation: HR, hazard ratios; ILSBPD, inter-leg systolic blood pressure difference; MACE, major adverse cardiovascular events.

Fig 2. Additional prognostic value of ILSBPD in MACE.

The additional prognostic value of ILSBPD is presented in the prediction models with age, sex, and clinical factors. (A) the prognostic value of ILSBPD for categorical variables (<16 vs. ≥16 mmHg). (B) the prognostic value of ILSBPD for continuous variables. The clinical factors included hypertension, diabetes mellitus, coronary artery disease, atrial fibrillation, chronic kidney disease, previous stroke, current smoker, and hemoglobin. Abbreviation: ILSBPD, inter-leg systolic blood pressure difference; MACE, major adverse cardiovascular events.