Atrial Remodeling Following Catheter-Based Renal Denervation Occurs in a Blood Pressure- and Heart Rate-Independent Manner.

OBJECTIVES: This study sought to investigate left atrial (LA) remodeling in relation to blood pressure (BP) and heart rate (HR) after renal sympathetic denervation (RDN). BACKGROUND: In addition to reducing BP and HR in certain patients with hypertension, RDN can decrease left ventricular (LV) mass and ameliorate LV diastolic dysfunction. METHODS: Before and 6 months after RDN, BP, HR, LV mass, left atrial volume index (LAVI), diastolic function (echocardiography), and premature atrial contractions (PAC) (Holter electrocardiogram) were assessed in 66 patients with resistant hypertension. RESULTS: RDN reduced office BP by 21.6 ± 3.0/10.1 ± 2.0 mm Hg (p < 0.001), and HR by 8.0 ± 1.3 beats/min (p < 0.001). At baseline, LA size correlated with LV mass, diastolic function, and pro-brain natriuretic peptide, but not with BP or HR. Six months after RDN, LAVI was reduced by 4.0 ± 0.7 ml/kg/m(2) (p < 0.001). LA size decrease was stronger when LAVI at baseline was higher. In contrast, the decrease in LAVI was not dependent on LV mass or diastolic function (E/E' or E/A) at baseline. Furthermore, LAVI decreased without relation to decrease in systolic BP or HR. Additionally, occurrence of PAC (median of >153 PAC/24 h) was reduced (to 68 PAC/24 h) by RDN, independently of changes in LA size. CONCLUSIONS: In patients with resistant hypertension, LA volume and occurrence of PAC decreased 6 months after RDN. This decrease was independent of BP and HR at baseline or the reduction in BP and HR reached by renal denervation. These data suggest that there is a direct, partly BP-independent effect of RDN on cardiac remodeling and occurrence of premature atrial contractions.

Improvements in left ventricular hypertrophy and diastolic function following renal denervation: effects beyond blood pressure and heart rate reduction.

OBJECTIVES: This study sought to investigate the interaction between blood pressure (BP) and heart rate (HR) reduction and changes in left ventricular (LV) structure and function following renal sympathetic denervation (RDN). BACKGROUND: Hypertension results in structural and functional cardiac changes. RDN reduces BP, HR, and LV mass and improves diastolic dysfunction. METHODS: We evaluated LV size, mass, and function before and 6 months after RDN in 66 patients with resistant hypertension and analyzed results in relation to systolic BP (SBP) and HR. RESULTS: SBP decreased by 11 ± 3 mm Hg in the first, 18 ± 5 mm Hg in the second, and 36 ± 7 mm Hg in the third tertile of SBP at baseline (p < 0.001). HR decreased by 13 ± 4 beats/min, 8 ± 3 beats/min, and 11 ± 6 beats/min in tertiles of SBP (p for interaction between tertiles = 0.314). In all SBP tertiles, LV mass index (LVMI) decreased similarly (LVMI -6.3 ± 2.2 g/m(2.7), -8.3 ± 2.1 g/m(2.7), and -9.6 ± 1.9 g/m(2.7); p for interaction = 0.639). LVMI decreased unrelated to HR at baseline (p for interaction = 0.471). The diastolic parameters E-wave deceleration time, isovolumetric relaxation time, and E'-wave velocity improved similarly in all tertiles of SBP and HR. Changes in LV mass and function were also unrelated to reduction in SBP or HR. Vascular compliance improved dependently on BP but independently of HR reduction. CONCLUSIONS: In patients with resistant hypertension, LV hypertrophy and diastolic function improved 6 months after RDN, without significant relation to SBP and HR. These findings suggest a direct effect of altered sympathetic activity in addition to unloading on cardiac hypertrophy and function.