Effects of Low Intensity Therapeutic Ultrasound on Endothelial Function

Not Applicable

Completed

• Conditions: Diabetes Mellitus, Type 2
• Interventions: Other: Low intensity therapeutic ultrasound

• Registration Number: NCT02872922
• Lead Sponsor: Universidade Federal de Santa Maria

Brief Summary

Endothelium is a cell layer that interposes blood and smooth muscle of vessels. This biological sensor reacts to physical and chemical stimuli by synthesis and/or liberation of regulatory substances like nitric oxide (NO), which acts on vascular tone, growth of muscle cells and platelet aggregation and leukocyte. Clinically, endothelial function measured by technique flow-mediated dilation (FMD) is a strong predictor of cardiovascular events and all-cause mortality. Previo study demonstrated that continuous and pulsed therapeutic 1-MHz ultrasound waveforms improved endothelial function in health volunteers and this vasodilation persisted for 20 min, which provided them with anti-inflammatory vascular effects. In subjects with type 2 diabetes (DM2) the chronical hyperglycemia and dyslipidemia reduce NO bioavailability causing endothelial dysfunction. Low intensity therapeutic ultrasound is an electrotherapeutic instrument employed in musculoskeletal injuries that promotes endothelium-dependent vasodilation, and its mechanism of action has not been studied on DM2. The aim of our study is evaluate endothelial function of patients with DM2 after different waveforms (placebo, continuous and pulsed) of therapeutic ultrasound. Therapeutic ultrasound is a electrotherapeutic instrument that can changes arterial endothelial function of subjects with DM2 because of NO bioavailability increasing, which implies anti-inflammatory and vasodilatory beneficial alterations for diabetic patients.

Detailed Description

Evaluation of endothelial function will be made by flow-mediated dilation (FMD). The therapeutic ultrasound will applied over brachial artery using continuous (CUT: 0,4W/cm2), pulsed (PUT: 20% duty cycle, 0,08W/cm2SATA) and Placebo (equipment off) waveforms during 5min in 3 intercalated days.

Study Timeline

• Study First Submitted: 2016-08-11
• Study First Submitted QC: 2016-08-15
• Study First Posted: 2016-08-19
• Study Start: 2016-12-10
• Status Verified: 2017-09
• Primary Completion: 2017-09-20
• Study Completion: 2017-09-20
• Last Update Submitted: 2017-09-20
• Last Update Posted: 2017-09-21

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 22

Inclusion Criteria

• The subjects that joined the study will be alphabetized volunteers
• Age between 25 and 65 years old,
• Absence of morbid obesity,
• Non-smokers,
• With no symptoms of skeletal muscle disorders,
• No previous performing cardiovascular surgery,
• No previous diagnose of rheumatic, neurological, oncological, immune or hematologic diseases,
• Without evidence of psychiatric diseases and/or cognitive deficit.

Exclusion Criteria

• Insulin dependent diabetes
• Leukocytosis, impaired fasting glycemia (<70 and >300 mg/dL) and
• Brachial artery diameter less than 2.5mm and larger than 5.0mm.
• On the day of the assessments have consumed of the alcoholic drink, caffeine and citrus juice

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Endothelial function after PLACEBO	Low intensity therapeutic ultrasound	In the placebo intervention, all of the procedures above are repeated, but with the ultrasound equipment powered off. Endothelial function of the all patients before and after application placebo waveform of ultrasound therapy measured by technique flow-mediated dilation (FMD)
Endothelial function after PWUT	Low intensity therapeutic ultrasound	Endothelial function of the all patients before and after application pulsed waveform of ultrasound therapy (PWUT) measured by technique flow-mediated dilation (FMD).
Endothelial function after CWUT	Low intensity therapeutic ultrasound	Endothelial function of the all patients before and after application continuous waveform of ultrasound therapy (CWUT) measured by technique flow-mediated dilation (FMD).

Primary Outcome Measures

Name	Time	Method
Percentage of the endothelium-dependent vasodilation (%FMD)	Five minutes after application of therapeutic ultrasound	Vessel diameter responses to reactive hyperemia are expressed as percentage change in relation to diameter before cuff inflation (%FMD = \[(hyperemia maximum diameter - baseline precuff diameter)/(baseline precuff diameter)\] / 100) (Corretti et al. 2002; Thijssen et al. 2011).; Baseline precuff diameter is expressed in millimeter (mm). Hyperemia maximum diameter is expressed in millimeter (mm). Arterial endothelium-dependent vasodilation are evaluated by technique flow-mediated dilation (FMD) with high-resolution vascular ultrasound and a 5- to 12-MHz linear transducer (Logiq P6, GE Healthcare, GE Ultrasound Korea), according to the American Heart Association Guidelines (Corretti et al. 2002), with adjustments (Thijssen et al. 2011).

Secondary Outcome Measures

Name	Time	Method
Percentage of the endothelium-independent vasodilation (%NMD)	Five minutes after application of therapeutic ultrasound	Endothelium-independent vasodilation is measured after sublingual nitroglycerin (NMD) spray (0.4 mg). Vessel diameter responses nitroglycerin are expressed as percentage change in relation to diameter before cuff inflation and before drug administration (%NMD = \[(nitroglycerin maximum diameter - baseline precuff diameter)/(baseline precuff diameter)\] / 100) (Corretti et al. 2002; Iida et al. 2006; Thijssen et al. 2011). Baseline precuff diameter is expressed in millimeter (mm) and Nitroglycerin maximum diameter is expressed in millimeter (mm).

Trial Locations

Locations (1)

Universidade Federal do Rio Grande; 🇧🇷 Rio Grande, RS, Brazil