Table 1. Common indications and contraindications for stress echocardiography testing.

Exercise Stress Echocardiography Indications	Dobutamine Stress Echocardiography Indications	Vasodilator Stress Echocardiography Indications
SE:stress echocardiography; CTA: CT Angiography; CCS: Chronic Coronary Syndrome. 1 mmHg = 0.133 kPa.
1. Diagnosis of chronic coronary artery disease.	Same as exercise SE, particularly for patients unable to undergo exercise stress testing or for whom exercise stress testing is not ideal.	1. CCS patients unable to exercise or with contraindications to exercise, or those with poor resting echocardiographic images (which may complicate image interpretation post-exercise stress).
2. Risk stratification and prognosis assessment in patients with confirmed CCS via CTA or coronary angiography.		2. Patients with recurrent chest pain, typical exertional angina, or resting angina attacks, and ischemic ST-segment depression during resting or exercise stress test, but with normal or mild stenosis (below 20%) in coronary artery CTA or angiography, suggesting microvascular dysfunction, requiring observation of coronary flow reserve function.
3. Preoperative risk assessment for non-cardiac surgery in CCS patients.		3. CCS patients with known coronary artery borderline lesions (30%–70% diameter stenosis) or diameter stenosis below 90%, requiring observation of coronary flow reserve function or myocardial perfusion.
4. Evaluation of treatment effectiveness or recurrent chest pain post coronary revascularization surgery.		4. Evaluation of the effectiveness of pharmacological and non-pharmacological treatments.
5. Assessment of myocardial ischemia location and viability.		5. Unstable angina, non-ST-segment elevation myocardial infarction, and acute ST-segment elevation myocardial infarction patients requiring observation of coronary flow reserve function or myocardial perfusion during vasodilation, examinations can be performed after 6 days of onset.
6. Etiological diagnosis of exertional dyspnea (presence or absence of myocardial ischemia).
7. Assessment of coronary flow reserve function.
8. Evaluation of myocardial ischemic functional reserve.
Absolute Contraindications	Absolute Contraindications:	Absolute Contraindications
1. Patients with unstable conditions or complications of acute coronary syndrome, myocardial infarction within the last 2 days.	1. Allergy to dobutamine or atropine.	1. Active bronchospastic diseases (Adenosine and dipyridamole can cause bronchospasm, regadenoson less likely to cause).
2. Hemodynamically unstable or symptomatic malignant arrhythmias.	2. Patients with unstable conditions or complications of acute coronary syndrome, myocardial infarction within the last 3 days.	2. Baseline blood pressure lower than 90/60 mmHg or hypertension (systolic pressure >180 mmHg or diastolic pressure >110 mmHg).
3. Symptomatic severe aortic stenosis with mean transvalvular pressure gradient ≥40 mmHg.	3. Severe arrhythmias (recurrent sustained supraventricular arrhythmias, new significant ventricular arrhythmias, second or third-degree atrioventricular block).	3. Severe arrhythmias including hemodynamically significant arrhythmias, severe bradycardic arrhythmias (Second or third-degree atrioventricular block and sick sinus syndrome, except in patients with pacemakers).
4. Severe left ventricular outflow tract obstruction with mean pressure gradient ≥40 mmHg.	4. Severe hypertension (resting systolic pressure >180 mmHg, diastolic pressure >110 mmHg).	4. Unstable or complicated acute coronary syndrome.
5. Uncontrolled symptomatic heart failure.	5. Active myocarditis or endocarditis.	5. Symptomatic moderate to severe valvular heart disease (Severe aortic stenosis, Adenosine or regadenoson relatively safe).
6. Concomitant acute pulmonary embolism, pulmonary infarction, deep vein thrombosis.	6. Acute heart failure.	6. Acute myocarditis or pericarditis, acute aortic dissection, hypertrophic cardiomyopathy or other causes of outflow obstruction, clinically uncontrolled or symptomatic heart failure.
7. Concomitant acute myocarditis or pericarditis.	7. Left ventricular thrombus.	7. Severe liver or renal failure, electrolyte disturbances, drug poisoning, drug allergies.
8. Concomitant acute aortic dissection.		8. Pregnancy, breastfeeding, moderate to severe anemia, hyperthyroidism, mental disorders.
9. Pregnancy.
Relative Contraindications	Relative Contraindications	Relative Contraindications
1. Left main coronary artery stenosis.	1. Paroxysmal supraventricular arrhythmias.	1. Use of methylene blue.
2. Moderate aortic valve stenosis (mean transvalvular pressure gradient of 20–40 mmHg).	2. Moderate to severe aortic valve stenosis.	2. History of allergic respiratory diseases.
3. Electrolyte abnormalities.	3. Resting left ventricular outflow tract obstruction (maximum pressure gradient >30 mmHg).	3. Intake of adenosine receptor antagonists and drugs that increase adenosine concentration, effects of adenosine influenced by intake of caffeine, tea, chocolate within <12 hours.
4. Severe hypertension (resting systolic pressure >180 mmHg or diastolic pressure >110 mmHg).	4. Aortic aneurysm >4.0 cm.
5. Uncontrollable tachycardia or bradycardia.