Case Report: Combination of Pressure Guidewire and Optical Coherence Tomography-Guided Drug-Coated Balloon Revascularization for Renal Artery Fibromuscular Dysplasia

Fibromuscular dysplasia (FMD) is the second common cause of renovascular hypertension. With the advent of endovascular therapy, angiography has become a diagnostic gold standard for FMD. Optical coherence tomography (OCT) by reflecting in vivo histology may improve diagnostic and classification accuracy. Renal fractional flow reserve (rFFR), measured by pressure guidewire, may distinguish the patients who may benefit from revascularization by identifying physiologically significant stenoses. However, the role of usage of both OCT and rFFR is not well-studied. We herein report a 17-year-old male with renovascular hypertension due to FMD. Angioplasty of drug-coated balloon (DCB) guided by OCT and FFR favorably achieved blood pressure (BP) control. In conclusion, the utility of both OCT and FFR may be useful for the appropriate selection of patients with renal FMD.

Soluble Guanylate Cyclase-Mediated Relaxation in Aortas from Rats with Renovascular Hypertension

Soluble guanylate cyclase (sGC) plays an important role in nitric oxide (NO)-mediated regulation of vascular tone; however, NO bioavailability is often reduced in diseased blood vessels. Accumulating evidence suggests that a shift of sGC from the NO-sensitive form to the NO-insensitive form could be an underlying cause contributing to this reduction. Herein, we investigated the impact of renovascular hypertension on NO-sensitive and NO-insensitive sGC-mediated relaxation in rat aortas. Renovascular hypertension was induced by partially clipping the left renal artery (2-kidneys, 1-clip; 2K1C) for 10 weeks. Systolic, diastolic, and mean arterial pressures were significantly increased in the 2K1C group when compared with the sham group. In addition, plasma thiobarbituric acid reactive substances and aortic superoxide generation were significantly enhanced in the 2K1C group when compared with those in the sham group. The vasorelaxant response of isolated aortas to the sGC stimulator BAY 41-2272 (NO-sensitive sGC agonist) was comparable between the sham and 2K1C groups. Likewise, the sGC activator BAY 60-2770 (NO-insensitive sGC agonist)-induced relaxation did not differ between the sham and 2K1C groups. In addition, the cGMP mimetic 8-Br-cGMP (protein kinase G agonist) induced similar relaxation in both groups. Furthermore, there were no differences in BAY 41-2272-stimulated and BAY 60-2770-stimulated cGMP generation between the groups. These findings suggest that the balance between NO-sensitive and NO-insensitive forms of sGC is maintained during renovascular hypertension. Therefore, sGC might not be responsible for the reduced NO bioavailability observed during renovascular hypertension.

Overview on Renovascular Hypertension: Review Article

Renovascular hypertension (RVH) is a prevalent cause of secondary hypertension that frequently develops to resistant hypertension. It is characterised as systemic hypertension that develops as a result of a restricted blood supply to the kidneys. Patients cannot be recognized clinically from those with essential hypertension; therefore, diagnosis requires arteriography, however urography and isotope renography may hint to the diagnosis. Atherosclerotic renal artery stenosis (ARAS) and fibromuscular dysplasia are the two most prevalent causes of RVH. The ultimate objective of controlling RVH, like with other kinds of hypertension, is to minimize the morbidity and mortality associated with high blood pressure The widespread use of effective antihypertensive medication treatment, statins, and other strategies to control vascular disease has resulted in remarkable improvements. In this review we will be looking at etiology, pathogenesis and treatment or RVH.

Long-term outcomes of angioplasty for pediatric renovascular hypertension: A single-center experience

Objectives We used single-center data to evaluate the long-term outcome of percutaneous transluminal angioplasty (PTA) for pediatric renovascular hypertension (RVH) and to analyze the factors that influence effectiveness. Methods We retrospectively evaluated 33 pediatric RVH patients (18 boys; mean age: 9.1 ± 4 years, range: 2–16) who underwent PTA from January 2007 to December 2019. 15 patients had Takayasu arteritis (TA) and 18 were non-TA. The median follow-up from the initial PTA was 69 months (range: 12–157; IQR: 25.5–89). Results The technical success rate of 52 PTA procedures was 90.4% in 33 children. Renal artery stents were implanted in two patients, external guidewires were used in two patients, and a drug-coated balloon was used in only one patient. The overall effective rate of PTA was 63.6%, including cured 39.4% and improved 24.2%, at the end of follow-up. Overall clinical outcomes were not statistically different between the TA and non-TA groups ( p = 0.316), nor were cure rates ( p = 0.072). 15 patients received reintervention due to restenosis after the first successful PTA; the interval was 2–56 months (median: 12 months). Four patients received reintervention due to a failed PTA. A total of four patients received open surgery. Binary logistics regression analysis showed that stenosis length and residual stenosis rate were strongly correlated with effective PTA ( p = 0.045, p = 0.044). Conclusions As a primary treatment for pediatric RVH, PTA can achieve satisfactory results, which are influenced by lesion length and residual stenosis rate.