Differences in resting and ambulatory blood pressure data in coarctation of aorta vs idiopathic hypertension

Abstract

Abstract Background Ambulatory systolic blood pressure (SBP) is more sensitive than resting-SBP in detecting hypertension in patients with coarctation of aorta (COA) and patients with idiopathic hypertension. A recent study showed that compared to patients with idiopathic hypertension with similar resting-SBP, COA patients had lower arterial compliance, and hence experienced higher SBP per unit increase in stroke volume during exercise. The purpose of this study was to compare resting vs ambulatory-SBP relationship between COA patients and non-COA patients (with and without hypertension), and to determine if ambulatory-SBP had better correlation with left ventricular (LV) remodeling as compared to resting-SBP. Methods Case-control study of 106 COA patients and 106 patients with idiopathic hypertension (ControlHTN+ group) matched by age, sex, body mass index and resting-SBP. Resting/ambulatory BP relationship in COA patients and patients with idiopathic hypertension were also compared to that of 19 patients without hypertension (ControlHTN- group). LV remodeling was assessed using LV mass index, e', and E/e'. Results Although the COA and ControlHTN+ groups had similar resting-SBP (by design), the COA group had a higher ambulatory-SBP and a higher prevalence of masked hypertension (30% vs 12%, p<0.001). There was a stronger correlation between ambulatory-SBP (as compared to resting-SBP) and LVMI (r=0.36 vs r=0.55, p=0.042), and average E/e' (r=0.42 vs r=0.59, p=0.046), in the COA group but not the ControlHTN+ group. There was no difference in the resting/ambulatory BP relationship between ControlHTN+ and ControlHTN- groups, but both groups were significantly different from the COA group. Conclusion These results highlight the unique differences in disease pathophysiology between hypertension in patients with COA and those with idiopathic hypertension, and also suggest that ambulatory-SBP may be a more accurate measure of LV pressure overload in COA patients. This underscores the potential limitations of relying on resting-SBP alone for clinical decision making. Funding Acknowledgement Type of funding source: None