Israel Medical Association Journal

Background: Apparent treatment-resistant hypertension (aTRH) is a high-risk phenotype associated with increased cardiovascular and renal morbidity. Renal denervation (RDN) has emerged as a promising intervention for patients with refractory blood pressure (BP) despite maximal medical therapy.

Objectives: To present the first Israeli prospective cohort evaluating RDN outcomes in aTRH patients.

Methods: The Tel Aviv Renal Denervation registry is a single-center, prospective cohort of 19 patients with aTRH who underwent RDN between 2021 and 2024. Baseline data included demographics, co-morbidities, medication burden, ambulatory BP monitoring (ABPM), and renal function. Outcomes were assessed at 3 and 12 months post-procedure, with repeated measures analyses used to evaluate longitudinal trends.

Results: The cohort (median age 62 years, 42% female) exhibited a high burden of co-morbidities including ischemic heart disease (37%), diabetes (26%), and chronic kidney disease (21%). Baseline ABPM showed a median 24-hour systolic BP of 152 mmHg. Following RDN, mean systolic BP decreased to 143 mmHg at 3 months and 138 mmHg at 12 months (P = 0.097), with a significant reduction in nighttime systolic BP (P = 0.033). Pill burden decreased from a median of 7 to 4 pills daily (P = 0.037). The number of antihypertensive drug classes declined from 6 to 4 (P = 0.052). Renal function remained stable throughout follow-up.

Conclusions: In this Israeli RDN cohort, patients with aTRH experienced clinically meaningful reductions in BP and medication burden, with preserved renal function and minimal complications. These findings support further expansion of national RDN registries to better guide patient selection and optimize long-term outcomes.

Mesenchymal stem cells, or mesenchymal stromal cells, have emerged as a major new cell technology with a diverse spectrum of potential clinical applications. MSCs[1] were originally conceived as stem/progenitor cells to rebuild diseased or damaged tissues. Over the last 14 years, since the first report of MSC infusions in patients, the cells have been shown to suppress graft vs. host disease, stimulate linear growth in a genetic disorder of bone, and foster engraftment of haplo-identical hematopoietic stem cells. In all cases, few, if any, MSCs were identified at the site of clinical activity. This experience suggests a remarkable clinical potential, but a different general mechanism of action. Systemically infused MSCs seem to exert a therapeutic effect effect through the release of cytokines that act on local, or perhaps distant, target tissues. Rather than serving as stem cells to repair tissues, they serve as cellular factories that secrete mediators to stimulate the repair of tissues or other beneficial effects. Since both the tissue source of MSCs and the ex vivo expansion system may significantly impact the cytokine expression profile, these parameters may be critically important determinants of clinical activity. Furthermore, cell processing protocols may be developed to optimize the cell product for a specific clinical indication. For example, MSC-like cells isolated from placenta and expanded in a three-dimensional bioreactor have recently been shown to increase blood flow in critical limb ischemia. Future efforts to understand the cytokine expression profile will undoubtedly expand the range of MSC clinical applications.