QuantaFlo HD test for finger blood flow during a forced exhale

QuantaFlo HD Clinical Validation Study

Observational Semler Scientific · NCT07219693

This test tries to see if a finger blood-flow measurement taken during a forced exhale matches echo measures of heart function in adults with cardiovascular disease or risk factors.

Quick facts

Study typeObservational
Enrollment600 (estimated)
Ages22 Years and up
SexAll
SponsorSemler Scientific Industry-sponsored
Locations1 site (Tucson, Arizona)
Trial IDNCT07219693 on ClinicalTrials.gov

What this trial studies

This observational validation compares transthoracic echocardiography (Echo) measurements, including global longitudinal strain (GLS), with the QuantaFlo HD finger blood-flow test performed during a forced expiration. The protocol examines whether Echo-measured GLS values greater than -16% correspond with abnormal responses on the QuantaFlo HD test. Adults aged 22 and older with cardiovascular disease, peripheral artery disease, or at least two risk factors (hypertension, diabetes, hyperlipidemia) are eligible if they can safely perform the forced exhale test. Testing is performed at a single site (Pima Heart and Vascular in Tucson, AZ) under sponsorship from Semler Scientific.

Who should consider this trial

Good fit: Adults 22 years and older with known cardiovascular disease or peripheral artery disease, or with at least two risk factors (hypertension, diabetes, high cholesterol), who can safely perform a forced expiration are ideal candidates.

Not a fit: Patients who cannot safely perform a forced expiration, have a pacemaker/ICD with pacing function, recent cardiothoracic or recent eye surgery, uncontrolled severe hypertension, severe tremors, or terminal illness may not benefit or be eligible.

Why it matters

Potential benefit: If successful, this could provide a quick, noninvasive finger-based test to help identify abnormal cardiovascular function.

How similar studies have performed: This specific finger blood-flow during forced expiration approach is relatively novel and there are limited published data directly linking it to echocardiographic GLS.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Male and female adult (≥ age 22) subjects with a minimum of 1 of the following:
* A history of Cardiovascular Diseasei or PAD
* Recorded history of at least two of the following
* Hypertension
* Diabetes
* Hyperlipidemia

Exclusion Criteria:

* Unable to safely perform a forced expiration, or unable to obtain a technically adequate FE test result
* Subjects with a pacemaker or ICD with pacemaker function
* Terminal advanced illness
* Recent cardiothoracic surgery (within 12 months)
* Retinal eye disease with anticoagulants
* History of eye surgery, within 90 days
* Uncontrolled hypertension \>180 mmHg systolic pressure or \>100 mmHg diastolic pressure
* Subjects with severe tremors

Where this trial is running

Tucson, Arizona

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions To Assess Cardiovascular Functioncardiovascular functiontransthoracic echocardiographyglobal longitudinal strain
Last reviewed 2026-06-09 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.