A Plant-Based Diet in the Treatment of Coronary Microvascular Dysfunction

NCT07821372 | Not Yet Recruiting

• 2 other identifiers: 2026P0013771K99HL181306-01A1
• Study Type: interventional
• Target: 20
• Locations: 1 country
• Sites: 1

Brief Summary

This study will evaluate whether a fully provided, unrefined, polyphenol-rich plant-based diet can improve blood vessel function in adults with coronary microvascular dysfunction (CMD), a condition that causes reduced blood flow in the small vessels of the heart despite the absence of major coronary artery blockages. Participants will follow the diet for 12 weeks while continuing their usual medical care. Researchers will assess changes in vascular function, symptoms, blood pressure, blood lipids, and other health measures throughout the study. Participants have up to 60 days after consent to complete screening and pre-intervention baseline assessments, potentially over two visits. Day 0 is counseling/education, and diet initiation. Weeks 4, 8, and 12 are measured from Day 0.

Conditions

Coronary Microvascular Dysfunction

Keywords

Coronary Microvascular Dysfunction; Plant-Based Diet; Flow-Mediated Dilation

Outcome Measures

Primary Outcomes (1)

• Change in Brachial Artery Flow-Mediated Dilation (FMD)

  Brachial artery flow-mediated dilation (FMD) will be assessed by ultrasound and reported as the percentage increase in brachial artery diameter from the resting pre-occlusion diameter to the peak post-occlusion diameter. FMD is a continuous physiological measurement. Higher FMD percentages indicate greater endothelium-dependent vasodilation and better peripheral endothelial function. Change from baseline will be calculated as the FMD percentage at each post-baseline visit minus the baseline FMD percentage and reported in percentage points.

  Baseline (pre-intervention), Week 4, Week 8, and Week 12

Secondary Outcomes (29)

• Change in Cutaneous Microvascular Function

  Baseline, Week 4, Week 8, and Week 12

• Change in Digital Endothelial Function

  Baseline, Week 4, Week 8, and Week 12

• Change in Central Arterial Stiffness

  Baseline, Week 4, Week 8, and Week 12.

• Change in Systemic Redox Status

  Baseline, Week 4, Week 8, and Week 12.

• Change in Total cholesterol concentration

  Baseline, Week 4, Week 8, and Week 12

Other Outcomes (3)

• Percentage of Prescribed Study Foods Consumed Assessed by ASA24 Dietary Recalls

  Day 0 through Week 12

• Number of Participants With Animal-Food DNA Detected by FoodSEQ

  Day 0 through Week 12

• Number of Participants Who Complete the 12-Week Intervention

  Week 12.

Study Arms (1)

Plant-Based Diet Intervention

EXPERIMENTAL

Participants with clinically documented coronary microvascular dysfunction (CMD) will receive a fully provided, weight-maintaining, unrefined, polyphenol-rich plant-based diet for 12 weeks while continuing clinician-directed medical care. The dietary intervention emphasizes fruits, vegetables, legumes, whole grains, nuts, and seeds and excludes animal products and highly processed foods. Participants will also receive dietary counseling and vitamin B12 supplementation. Participants have up to 60 days after consent to complete screening and pre-intervention baseline assessments, potentially over two visits. Day 0 is counseling/education, and diet initiation. Weeks 4, 8, and 12 are measured from Day 0

Other: Polyphenol-Rich Plant-Based Diet

Interventions

Polyphenol-Rich Plant-Based Diet OTHER

A fully provided, weight-maintaining, unrefined, polyphenol-rich plant-based dietary intervention administered for 12 weeks. The diet is designed around whole plant foods, including fruits, vegetables, legumes, whole grains, nuts, and seeds, and excludes animal products, refined grains, added sugars, sugar-sweetened beverages, and commercially processed plant-based meat or cheese substitutes. Participants receive nutrition education, ongoing dietary counseling, meal provision, and vitamin B12 supplementation throughout the intervention period

Plant-Based Diet Intervention

Eligibility Criteria

• Age: 45 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Women must be postmenopausal.
• History of angina, ischemic symptoms, or symptoms consistent with ischemia in the absence of obstructive coronary artery disease.
• No obstructive coronary artery disease (\<50% stenosis in any epicardial coronary artery or fractional flow reserve \>0.80).
• Clinically documented coronary microvascular dysfunction (CMD), including coronary flow reserve \<2.5 and/or index of microcirculatory resistance ≥25, or equivalent documentation in the medical record.
• Stable cardiometabolic medication regimen for at least 2 months before enrollment.
• Willingness to consume the study-provided plant-based diet and complete all study procedures.
• Ability to provide informed consent

You may not qualify if:

• Obstructive coronary artery disease or prior coronary revascularization (PCI or CABG).
• Recent acute coronary syndrome, unstable angina, decompensated heart failure, or other clinically unstable cardiovascular disease.
• Significant structural heart disease, uncontrolled arrhythmia, severe uncontrolled hypertension, or symptomatic hypotension.
• Severe renal disease (eGFR \<30 mL/min/1.73 m²) or significant liver disease.
• Current vegetarian or vegan diet, or habitual consumption of ≤4 servings of animal products per week.
• Severe food allergies, dietary restrictions, or gastrointestinal conditions that would prevent adherence to the study diet.
• Current use of weight-loss medications, including GLP-1 receptor agonists.
• Active eating disorder.
• Recent (\>5%) intentional or unintentional weight change within the previous 3 months.
• Participation in another interventional study that could affect study outcomes.
• Any medical, psychiatric, or social condition that, in the investigator's judgment, would make participation unsafe or interfere with study completion.

Sponsors & Collaborators

• Emory University: lead
• National Heart, Lung, and Blood Institute (NHLBI): collaborator

Study Sites (1)

Emory University

Atlanta, Georgia, 30322, United States

Location

Study Officials

• Rami Najjar, PhD

  Emory University

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Rami S Najjar, PhD

CONTACT

678-235-4609; rnajjar@emory.edu

Rami Najjar

CONTACT

rnajjar@emory.edu

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Post doc fellow

Study Record Dates

• First Submitted: August 31, 2026
• First Posted: September 15, 2026
• Study Start: October 1, 2026
• Primary Completion (Estimated): January 1, 2028
• Study Completion (Estimated): January 1, 2028
• Last Updated: September 15, 2026

Record last verified: 2026-09

Data Sharing

• IPD Sharing: Will share

Locations

US (1)