ChaMP-CMD: A Phenotype-Blinded, Randomized Controlled, Cross-Over Trial.

Area of Science:

• Cardiology
• Vascular Medicine
• Diagnostic Imaging

Background:

• Angina with nonobstructive coronary arteries (ANOCA) is a prevalent condition lacking established effective treatments.
• Coronary microvascular dysfunction is increasingly recognized as a cause of ANOCA.
• Identifying specific patient subgroups within ANOCA is crucial for targeted therapy.

Purpose of the Study:

• To investigate whether coronary flow reserve (CFR) measurement can identify ANOCA patients who benefit from anti-ischemic therapy.
• To compare the efficacy of amlodipine and ranolazine in ANOCA patients stratified by CFR.
• To guide the management of ANOCA based on physiological assessment.

Main Methods:

• A blinded, randomized crossover trial involving 87 ANOCA patients.
• Invasive CFR measurement was performed, classifying patients into coronary microvascular disease (CMD, CFR<2.5) and reference (CFR≥2.5) groups.
• Patients received amlodipine and ranolazine sequentially for 4 weeks each, with treadmill exercise time and Seattle Angina Questionnaire scores as primary and secondary outcomes.

Main Results:

• The CMD group showed significantly greater improvements in exercise time with both amlodipine and ranolazine compared to the reference group.
• The CMD group reported a significant improvement in Seattle Angina Questionnaire scores with ranolazine, but not amlodipine.
• These findings highlight a differential response to anti-ischemic therapy based on CFR.

Conclusions:

• Only ANOCA patients with impaired CFR (CMD group) derive significant benefit from anti-ischemic therapy.
• Measurement of CFR is a valuable tool for diagnosing and guiding the management of heterogeneous ANOCA patients.
• This approach enables personalized treatment strategies for ANOCA.