ANOCA - Angina With Non-obstructive Coronary Arteries
Conditions
Brief summary
This is a single-center, prospective interventional study evaluating noninvasive coronary function testing using transthoracic Doppler echocardiography of the left anterior descending coronary artery in patients with stable angina and nonobstructive coronary artery disease (ANOCA) who previously underwent invasive coronary function testing (adenosine and/or acetylcholine). A group of age- and sex-matched healthy volunteers will be enrolled to support interpretation of potentially abnormal noninvasive responses observed in patients.
Detailed description
Patients referred to the catheterization laboratory of Fondazione Policlinico Universitario A. Gemelli IRCCS for stable angina who show non-obstructive coronary artery disease at invasive coronary angiography and underwent invasive coronary function testing will be enrolled. During a transthoracic echocardiographic Doppler examination of the left anterior descending coronary artery, participants will undergo three standardized stimuli (hyperventilation, cold pressor test, and dipyridamole) separated by 30-minute intervals, with peak diastolic velocity measured at baseline and at the end of each test. For each stimulus, the coronary blood flow velocity response will be expressed as the ratio between peak and basal peak diastolic velocity. Participants will also complete the Seattle Angina Questionnaire to assess symptom burden. The primary aim of the study is to investigate the usefulness of studying coronary flow reserve by transthoracic color Doppler echocardiogram in reaching the diagnosis of microcirculation dysfunction and/or coronary vasomotor disturbance. The secondary aim of the study was to assess whether abnormalities on the stress echocardiogram with dipyridamole, hyperventilation, and cold-pressor test are related to the patient's symptoms.
Interventions
DIAGNOSTIC_TESTCoronary flow reserve assessed by Echocardiography
All patients and controls will undergo the following tests during transthoracic echocardiographic Doppler examination of the left anterior descending coronary artery, with time intervals of 30 minutes from each other: 1. hyperventilation test: the patient is asked to breathe at a rate of 30 respirations per minute, for 5 minutes; 2. cold pressor test: the patient puts his/her right hand in ice water for 2 minutes; 3. dipyridamole test: intravenous dipyridamole is administered at a dose of 0.84 mg/kg over 6 minutes; Peak diastolic velocity (PDV) of blood flow in the left anterior descending coronary artery will be measured before and at the end of each test by pulsed-wave Doppler, using a GE E95 echocardiographic machine. The ratio between peak flow velocity of coronary blood flow at peak of each test and the relative basal peak flow velocity of coronary blood flow is taken as the response of coronary blood flow velocity to each test.
Sponsors
Fondazione Policlinico Universitario Agostino Gemelli IRCCS
Study design
Allocation
NON_RANDOMIZED
Intervention model
SINGLE_GROUP
Primary purpose
DIAGNOSTIC
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
1. Age between 18 and 90 years; 2. ICA performed within the previous 12 months from enrollment and characterized by: (a) absence of obstructive CAD (\<50% diameter reduction or FFR by \>0.80); (b) invasive assessment of epicardial/microvascular spasm by acetylcholine test; 3. Signed informed consent.
Exclusion criteria
1. Presentation as an acute coronary syndrome (i.e. unstable chest pain) or a typical history of variant angina (frequent angina pain at rest with ST-segment elevation at the ECG, caused by recurrent coronary spasm); 2. Previous coronary revascularization with surgical intervention; 3. Asthma or known intolerance or contraindications to dipyridamole; 4. Serious medical conditions, including renal failure (eGFR \<30 mL/min), liver diseases, malignancies, and acute or chronic inflammatory diseases; 5. Pregnancy; 6. Psychological conditions that might hamper patient co-operation; 7. Any condition that, in the judgment of the investigators, would make difficult for the patient to complete the study protocol; 8. Missed informed consent.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Correlation (Phi coefficient) between TTE-induced vasoconstriction and acetylcholine-induced spasm at invasive assessment. | Periprocedural | The primary aim of the study is to investigate the usefulness of studying coronary flow reserve by transthoracic color Doppler echocardiogram in reaching the diagnosis of coronary vasomotor disturbance. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Agreement between dipyridamole-induced non-invasive coronary flow reserve and invasive coronary flow reserve | Periprocedural | Agreement between coronary flow reserve (CFR) measured by transthoracic echocardiography during dipyridamole stress and CFR measured during invasive coronary function testing. Unit of Measure: Pearson correlation coefficient |
| Agreement between cold pressor test-induced non-invasive coronary flow reserve and invasive coronary flow reserve | Periprocedural | Agreement between coronary flow reserve (CFR) measured by transthoracic echocardiography during cold pressor test and CFR measured during invasive coronary function testing. Unit of Measure: Pearson correlation coefficient |
| Association between abnormal non-invasive coronary vasomotor response and angina symptoms | Periprocedural | Comparison of Seattle Angina Questionnaire (SAQ) summary score between patients with abnormal versus normal coronary vasodilator response during stress echocardiography. Unit of Measure: SAQ summary score (0-100) |
Outcome results
None listed