Effects of therapeutic ultrasound on endothelial function: systematic review and meta-analysis

The vascular endothelium regulates capillary permeability and inflammation; its function predicts cardiovascular risk and mortality. Low-intensity therapeutic ultrasound (LITUS) may influence endothelial function, but the effects remain uncertain.

This systematic review with meta-analysis of clinical trials aims to evaluate the effects of LITUS on endothelial function in humans.

Placebo-controlled randomized clinical trials evaluating the effects of LITUS on endothelial function in humans were included. The studies were registered on PROSPERO (CRD42024534383). Data were extracted from MEDLINE (PubMed), Cochrane CENTRAL, SCIELO, EBSCO, EMBASE, and Web of Science databases, with no restrictions on year of publication or language, up to February 6, 2025. Methodological risk of bias was assessed using the Cochrane Risk of Bias 2.0 tool. Meta-analyses were conducted using Review Manager version 5.3, and the certainty of evidence was evaluated by GRADE.

Five randomized crossover clinical trials met the inclusion criteria, including data from 103 subjects (intervention and placebo). The methods used to evaluate endothelial function included flow-mediated dilation (in three studies), venous occlusion plethysmography, and laser Doppler flowmetry. The application of LITUS increased the endothelial function in pulsed (standard mean difference [SMD]: 0.88; CI 95%: 0.59 to 1.17; I²: 0%) and continuous (SMD: 1.09; CI 95%: 0.70 to 1.48; I²: 38%) waveforms. The certainty of the evidence was considered "moderate" for pulsed and continuous waveforms.

The pulsed and continuous waveforms of the LITUS improved endothelial function. These results indicates that the application of therapeutic ultrasound has benefits on vascular homeostasis.