se of Scintigraphy in the evaluation of the response to Renal Denervation in patients with treatment-resistant hypertensio
- Conditions
- Hypertension
- Registration Number
- RBR-10h5gd44
- Lead Sponsor
- Instituto Dante Pazzanese de Cardiologia
- Brief Summary
BACKGROUND: Renal denervation (RDN) is effective and safe in reducing blood pressure in resistant hypertensive patients. Some predictors of success have already been identified, but we still need a method that allows us to quantify and predict the chance of success. ¹²³I-meta-iodobenzylguanidine (¹²³I-mIBG) scintigraphy is a diagnostic method that offers the possibility of quantifying organ-specific presynaptic nerve activity. OBJETIVES: Our aim was to evaluate renal and cardiac uptake of ¹²³I-mIBG as a possible method of quantifying renal denervation and evaluate the potential of scintigraphy as a method to select patients who are candidates for renal denervation therapy. METHODS: From March 2018 to December 2022, we enrolled 39 patients in prospective, randomized, single-center, double-blind and placebo-controlled study (2:1 ratio). 26 patients underwent renal denervation (RDN), and 13 patients underwent sham procedure. Demographics characteristics, ABPM, laboratory tests and (¹²³I-mIBG) scintigraphy parameters were compared between and within groups. RESULTS: Our demographic data demonstrate a population at high cardiovascular risk. The mean time of hypertension was 19.5 ± 11.4 years. Renal and Cardiac ¹²³I-mIBG uptake and washout between RDN and sham groups, at different times, were similar at baseline, 1 and 6 months after RDN, demonstrating that in our study, the scintigraphy parameters were not able to detect changes caused by RDN. The number of ablations performed per patient in the RDN group, 77.12 ± 6.91. We observed a significant drop in ABPM 1 month after RDN with a mean SBP drop of 21.17 mmHg and DBP of 13.25 mmHg and a drop in SBP of 12.62 mmHg and DBP of 6.96 mmHg at 6 months. Number of antihypertensive medications prescribed in RDN group reduced from 6.8 ± 0.7 to 5 ± 1.7 at time 2 (p=0.0008) and 5.5 ± 1.8 at time 3 (p=0.01). Subgroup analyses showed that the responder patients had at baseline a lower HMR 15 than the non-responder group regarding both ABPM average systolic (p=0.01), ABPM average diastolic (p=0.03) and ABPM nighttime systolic (p=0.008). Thus, patients with lower HMR 15 are more likely to respond more significantly to RDN. Suggesting that patients with higher sympathetic activity expressed by lower HMR may be better responders. The baseline HMR 15 obtained on ABPM average systolic variation was a good predictor of chance of response to the procedure (responder) with area under the curve of 0.78. In the logistic regression models to predict the chance of responders to RDN using the change in ABPM average systolic we observed that baseline HMR 15 emerges as a predictor of response with OR (Odds ratio) of 0.002 (90% confidence interval 0-0.4984, p 0.07) so increasing baseline HMR 15 by 0.1 unit increases the chance by 85% of the individual being a non-responder in the model defining R by ABPM average systolic, and by 48% in the model defining R by ABPM average diastolic. CONCLUSION: No significant changes in renal ¹²³I-mIBG scintigraphy parameters analyzed after RDN with the Symplicity Spyral catheter between and within the RDN and sham groups. However, in the sub-analysis of the group undergoing RDN, the cardiac scintigraphy variables HMR 15 and HMR 4 and renal LK/BG may assist in the selection of candidates for RDN, increasing the chance of identifying responders or non-responders to the procedure, and should be regarded as hypothesis generator for studies specifically designed for this purpose.
- Detailed Description
Not available
Recruitment & Eligibility
- Status
- Data analysis completed
- Sex
- Not specified
- Target Recruitment
- Not specified
treatment resistant hypertension; age between 18 and 75 years old
Secondary hypertension; advanced chronic renal failure (creatinine clearance < 30 ml/min); abnormal renal vascular anatomy (diameter less than 3 mm; extent less than 20 mm; or stenosis greater than 30%); allergic reaction to the iodine contrast; pregnant women; unable to understand the study or sign the consent form; patients with decompensated heart failure; hemorrhagic diathesis; consumptive diseases; severe peripheral arterial obstructive disease; acute diseases such as coronary and cerebrovascular syndromes were excluded
Study & Design
- Study Type
- Intervention
- Study Design
- Not specified
- Primary Outcome Measures
Name Time Method Expected outcome 1: We expected to find reduced washout rates and increased heart/mediastinum (RCM), kidney/backside radiation (RD/BG and RE/BG) ratios after the renal denervation procedure. ;Outcome found 1: We observed that there was no statistical difference in the scintigraphic parameters at the different study times, before and after the randomized procedure, within and between the treatment and control groups, such as the heart/mediastinum ratio (MCR), kidney/backside radiation (RD/BG and RE/BG), and by the washout rates (RDW, REW, and MIOCW). As well as in the ratios between the two kidneys and liver (RD/FIG, RE/FIG), lung uptake (RD/PUL, RE/PUL), mediastinum (RD/MED, RE/MED), and the myocardium (RD/MIOC, RE/MIOC) on the 15-minute and 4-hour images.
- Secondary Outcome Measures
Name Time Method Secondary outcomes were not expected.