Effects of catheter-based renal denervation on cardiac sympathetic activity and innervation in patients with resistant hypertension.
OBJECTIVE
To investigate, whether renal denervation (RDN) has a direct effect on cardiac sympathetic activity and innervation density.


BACKGROUND
RDN demonstrated its efficacy not only in reducing blood pressure (BP) in certain patients, but also in decreasing cardiac hypertrophy and arrhythmias. These pleiotropic effects occur partly independent from the observed BP reduction.


METHODS
Eleven patients with resistant hypertension (mean office systolic BP 180 ± 18 mmHg, mean antihypertensive medications 6.0 ± 1.5) underwent I-123-mIBG scintigraphy to exclude pheochromocytoma. We measured cardiac sympathetic innervation and activity before and 9 months after RDN. Cardiac sympathetic innervation was assessed by heart to mediastinum ratio (H/M) and sympathetic activity by wash out ratio (WOR). Effects on office BP, 24 h ambulatory BP monitoring, were documented.


RESULTS
Office systolic BP and mean ambulatory systolic BP were significantly reduced from 180 to 141 mmHg (p = 0.006) and from 149 to 129 mmHg (p = 0.014), respectively. Cardiac innervation remained unchanged before and after RDN (H/M 2.5 ± 0.5 versus 2.6 ± 0.4, p = 0.285). Cardiac sympathetic activity was significantly reduced by 67 % (WOR decreased from 24.1 ± 12.7 to 7.9 ± 25.3 %, p = 0.047). Both, responders and non-responders experienced a reduction of cardiac sympathetic activity.


CONCLUSIONS
RDN significantly reduced cardiac sympathetic activity thereby demonstrating a direct effect on the heart. These changes occurred independently from BP effects and provide a pathophysiological basis for studies, investigating the potential effect of RDN on arrhythmias and heart failure.
Klinik für Innere Medizin III (Kardiologie, Angiologie und Internistische Intensivmedizin), Universitätsklinikum des Saarlandes, Kirrberger Str. 1, Geb. 40., 66421, Homburg/Saar, Germany.|Interdisciplinary Medical Research Center South Tyrol (IMREST), Bolzano, Italy.
Luca
L
Donazzan
Klinik für Innere Medizin III (Kardiologie, Angiologie und Internistische Intensivmedizin), Universitätsklinikum des Saarlandes, Kirrberger Str. 1, Geb. 40., 66421, Homburg/Saar, Germany.
Felix
F
Mahfoud
Klinik für Innere Medizin III (Kardiologie, Angiologie und Internistische Intensivmedizin), Universitätsklinikum des Saarlandes, Kirrberger Str. 1, Geb. 40., 66421, Homburg/Saar, Germany.
Sebastian
S
Ewen
Klinik für Innere Medizin III (Kardiologie, Angiologie und Internistische Intensivmedizin), Universitätsklinikum des Saarlandes, Kirrberger Str. 1, Geb. 40., 66421, Homburg/Saar, Germany.
Christian
C
Ukena
Klinik für Innere Medizin III (Kardiologie, Angiologie und Internistische Intensivmedizin), Universitätsklinikum des Saarlandes, Kirrberger Str. 1, Geb. 40., 66421, Homburg/Saar, Germany.
Bodo
B
Cremers
Klinik für Nuklearmedizin, Universitätsklinikum des Saarlandes, Homburg/Saar, Germany.
Carl-Martin
CM
Kirsch
Klinik für Nuklearmedizin, Universitätsklinikum des Saarlandes, Homburg/Saar, Germany.|Abteilung für Nuklearmedizin, Universitätsklinikum Regensburg, Regensburg, Germany.
Dirk
D
Hellwig
Klinik für Nuklearmedizin, Universitätsklinikum des Saarlandes, Homburg/Saar, Germany.
Tareq
T
Eweiwi
Klinik für Nuklearmedizin, Universitätsklinikum des Saarlandes, Homburg/Saar, Germany.
Samer
S
Ezziddin
Baker IDI Heart and Diabetes Institute, Melbourne, Australia.
Murray
M
Esler
Klinik für Innere Medizin III (Kardiologie, Angiologie und Internistische Intensivmedizin), Universitätsklinikum des Saarlandes, Kirrberger Str. 1, Geb. 40., 66421, Homburg/Saar, Germany. michael.boehm@uniklinikum-saarland.de.
Michael
M
Böhm
D019797:3-Iodobenzylguanidine; D000368:Aged; D000959:Antihypertensive Agents / Q000627:therapeutic use; D001794:Blood Pressure / Q000187:drug effects; D018660:Blood Pressure Monitoring, Ambulatory; D017115:Catheter Ablation / Q000009:adverse effects; D004351:Drug Resistance; D005260:Female; D006321:Heart / Q000000981:diagnostic imaging / Q000294:innervation*; D006801:Humans; D006973:Hypertension / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D007668:Kidney / Q000098:blood supply*; D008297:Male; D008875:Middle Aged; D019275:Radiopharmaceuticals; D012008:Recurrence; D012077:Renal Artery / Q000294:innervation*; D013562:Sympathectomy / Q000009:adverse effects / Q000379:methods*; D013564:Sympathetic Nervous System / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D013997:Time Factors; D016896:Treatment Outcome; D051598:Whole Body Imaging
D000959:Antihypertensive Agents; D019275:Radiopharmaceuticals; D019797:3-Iodobenzylguanidine
Arrhythmias; Heart failure; MIBG; Renal denervation; Resistant hypertension