A phase III study to compare SonoVue® enhanced myocardial echocardiography (MCE) to single photon emission computerized tomography (ECG-GATED SPECT), at rest and at peak of low-dose Dipyridamole stress test, in the assessment of significant coronary artery disease (CAD) in patients with suspect or known CAD using Coronary Angiography as Gold Standard

* Having at least 18 years of age.
* Having a known or suspected coronary artery disease (CAD) indicated for stress ECGgated SPECT and/or coronary angiography to clarify whether they have a clinical
significant coronary stenosis (*70%).
* Having provided written Informed Consent and willing to comply with protocol
requirements.

Has any clinically unstable cardiac condition prior to SonoVue® administration such as:
- evolving or ongoing myocardial infarction,
- a history of acute myocardial infarction or PCI within the previous 3 months,
- worsening of typical angina at rest within the previous 7 days,
- significant worsening of cardiac symptoms within the previous 7 days,
- recent coronary artery intervention or other factors suggesting clinical instability
(e.g., recent deterioration of ECG, laboratory or clinical findings),
- acute cardiac failure, class III/IV cardiac failure,
- severe cardiac rhythm disorders (ventricular tachycardia sustained and not sustained in combination with symptoms).
* Has any contra-indications to dipyridamole or aminophylline (e.g. hypersensitivity to xanthines) according to each agent*s package insert.
* Has any known allergy to one or more of the ingredients of the investigational product.
* Has a previous Coronary Artery By-pass.
* Has any revascularization procedure or change of clinical status that may warrant a change in their status of CAD among the clinical testing under evaluation (coronary angiography, MCE or ECG-GATED SPECT).
* Has used methylated xanthines (chocolate, caffeine * including coffee, tea, and cola drinks), phosphodiesterase inhibitor drugs such as aminophylline or dipyridamole within 24 hours prior SonoVue® enhanced echocardiography or SPECT.
* Has not visualization of left ventricle at basal echocardiography.
* Has received an investigational compound within 30 days before admission into this study.
* Has any medical condition or other circumstances which would significantly decrease the chances of obtaining reliable data, achieving study objectives, or completing the study and/or post dose follow-up examinations.
* Is determined by the Investigator that the subject is clinically unsuitable for the study.
* Is a pregnant or lactating female. Exclude the possibility of pregnancy:
* by testing on site at the institution (serum or urine *HCG) within 24 hours prior to the start of investigational product administration,
- by surgical history (e.g., tubal ligation or hysterectomy),
- post menopausal with a minimum 1 year without menses.