Recruiting

Leg Heat Therapy

Sponsor:

Indiana University

Code:

NCT06388226

Conditions

Heart Failure With Preserved Ejection Fraction

Eligibility Criteria

Sex: All

Age: 18+

Healthy Volunteers: Not accepted

Interventions

Leg heat therapy

Leg sham therapy

Study Details

Brief summary:

The objective of this pilot study is to establish evidence to support the validity of HT in improving skeletal muscle function and physical capacity of patients with HFpEF. Our central hypothesis is that HT treatment will lead to improvements in skeletal muscle and microvascular function compared to a control intervention. As a result, we anticipate that patients treated with HT will demonstrate improved skeletal muscle microvascular blood flow and oxygenation resulting in enhanced exercise tolerance. To explore this hypothesis, we propose the following specific aim: Explore the effects of home-based HT on exercise tolerance in patients with HFpEF.

Conditions

Heart Failure With Preserved Ejection Fraction

Study ID

NCT06388226

Start date

Aug 15, 2024

Status verified date

Nov, 2025

Completion date

Aug 31, 2026

Anticipated

Primary completion date

Aug 20, 2026

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 18+

Healthy Volunteers: Not accepted

Inclusion Criteria:

  • Men and women older than 18 years
  • Established diagnosis of heart failure with preserved ejection fraction (HFpEF) including left ventricular ejection fraction (LVEF) ≥50% as evidenced by Doppler echocardiography and/or ratio of the early mitral inflow velocity (E) to septal tissue Doppler velocity (e') >8 and at least 1 other sign of chronically elevated filling pressures, including an enlarged left atrium (left atrial volume index >34 mL/m2), an elevated N-terminal pro-brain natriuretic peptide (NT-pro-BNP) level within the past year, long-term loop diuretic use for control of symptoms, or elevated filling pressures (mean pulmonary capillary wedge pressure >12 mmHg) on prior cardiac catheterization
  • Stable medical treatment

Exclusion Criteria:

  • Recent hospitalization (within the previous 1 month)
  • Unstable angina and/or uncontrolled cardiac arrhythmia causing symptoms or hemodynamic compromise (including severe bradycardia or tachycardia, sick sinus syndrome, or multifocal premature ventricular contractions)
  • Presence of any clinical condition that makes the patient unsuitable to participate in the trial, e.g., significant ischemic or valvular heart disease, cor pulmonale, unstable coronary artery disease, primary renal (e.g., estimated glomerular filtration rate (eGFR) <25 mL/min/1.73 m2) or hepatic disease (e.g., aspartate aminotransferase and alanine aminotransferase levels >3.0 times the upper limit of the normal range), pulmonary, neuromuscular, orthopedic disorders, among others
  • Inability to exercise on the treadmill
  • Inability to provide informed consent
  • Concern for inability of the patient to comply with study procedures and/or follow up (e.g., alcohol or drug abuse)
  • Any contraindication to heat therapy and/or inability to fit into water-circulating trousers
  • Impaired thermal sensation in the leg

Study Design

Enrollment

90 participants

Anticipated

Allocation

Randomized

Intervention Model

Parallel Assignment

Primary purpose

Treatment

Interventions and Outcome Measures

Arms

experimental: Heat therapy

Patients will be provided with water-circulating trousers, a water heater, and a water tank coupled to a water pump. The heater will be adjusted to warm up the water to 42ºC. Participants will be asked to apply the therapy daily for 90 min while in the supine position.

sham comparator: Sham control

Patients will be provided with water-circulating trousers, a water heater, and a water tank coupled to a water pump. The heater will be adjusted to warm up the water to 33ºC. Participants will be asked to apply the therapy daily for 90 min while seated or in the supine position.

Interventions

Leg heat therapy

A sous vide heating immersion circulator heats up the water inside the water tank to 42ºC. A water pump circulates temperature-regulated water through the trousers.

Leg sham therapy

A sous vide heating immersion circulator heats up the water inside the water tank to 33ºC. A water pump circulates temperature-regulated water through the trousers.

Primary outcome measure

  • Change in time to exhaustion during treadmill exercise [ Time Frame: Baseline to 2-month follow-up ]

Central Contacts and Locations

Central contacts

Doris Muriathiri, MPH, CCRP

317-274-0903dmuriath@iu.edu

Daniel Hirai, PhD

765-494-7113dhirai@purdue.edu

Locations

IU Health Methodist

Recruiting

Indianapolis, Indiana, United States, 46202

Contacts

Doris Muriathiri, MPH, CCRP

317-274-0903dmuriath@iu.edu

IU Health University Hospital

Recruiting

Indianapolis, Indiana, United States, 46202

Contacts

Doris Muriathiri, MPH, CCRP

317-274-0908dmuriath@iu.edu

More Information

Sponsor

Indiana University

Last update posted

Nov 17, 2025

Last verified

Nov, 2025

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-09. This information was provided to ClinicalTrials.gov by Indiana University on 2025-11-17.