RESUMO
BACKGROUND: Renal denervation (RDN) can reduce blood pressure (BP) in patients with resistant hypertension, but less so in patients with isolated systolic hypertension. A possible explanation is that patients with stiffer arteries may have lesser neural contribution to their hypertension. METHOD: We hypothesized that arterial stiffness predicts the response to RDN. From ambulatory BP monitoring (ABPM), ambulatory arterial stiffness index (AASI) was calculated as 1â-âthe regression slope of DBP versus SBP. RESULTS: In 111 patients with resistant hypertension, RDN reduced office and 24-h SBP after 3, 6, and 12 months (by -11â±â22, -11â±â25, -14â±â21âmmHg for office, and -4â±â11, -5â±â12, -5â±â15âmmHg for 24-h SBP, respectively, Pâ<â0.01). Patients with baseline AASI above the median (>0.51) showed no change in 24-h SBP at 6 months after RDN (-0.4â±â12.3âmmHg, Pâ>â0.05), whereas an AASI below 0.51was associated with a marked reduction (-9.3â±â11.0âmmHg, Pâ<â0.01). Across AASI quartiles, patients in the highest quartile (AASIâ≥â0.60) had lower muscle sympathetic nerve activity than the other three quartiles (39â±â13 versus 49â±â13 bursts/min, Pâ=â0.035). The responder rate, defined as a 24-h SBP reduction of at least 5% was 58% in the lowest AASI quartile (<0.45) and 16% in the highest quartile (≥0.60). After adjustment for age, sex, BMI, office and 24-h SBP, an AASI less than 0.51predicted those who respond to RDN (odds ratio 3.46, Pâ=â0.04). CONCLUSION: We conclude that in patients with resistant hypertension, a lower AASI is an independent predictor of the BP response to RDN, possibly explained by a more pronounced neurogenic rather than biomechanical contribution to their BP elevation.