Aim of this study is to evaluate whether the length of coronary segments, assessed by an experienced operator, using the "optimal view" of standard 2-dimensional coronary angiography, is over/underestimated with respect to the one evaluated automatically with the help of a 3-dimensional coronary reconstruction model. Moreover, both techniques are compared with an "in-vivo" surrogate of the real length of the coronary segment under evaluation, i.e. an intra-coronary marker guide-wire, which is a wire with markers placed at fixed and known distance along its length in its distal (intra-coronary) part. Two hypotheses are tested: (1) the length of a coronary segment evaluated with a standard 2-dimensional "optimal view" over/underestimates the length assessed by a 3-dimensional coronary model that automatically detects the least foreshortened length of the segment under evaluation, and (2) the 3-dimensional model approximates more closely than standard 2-dimensional angiography, the real length of the segment detected by the marker guide-wire.

The potential to improve the accuracy of the assessment of the coronary tree by means of 3-D modeling reconstruction may lead to an evaluation of the coronary artery anatomy that approximates more correctly the real anatomy, thus subsequently leading to a more tailored diagnosis and therapy for the patients with ischemic heart disease.

Aim of the current study is to assess whether a 3-D model of the coronary tree offers a less foreshortened and less operator-dependent evaluation of the length of the coronary arteries with respect to standard coronary angiography. Furthermore, for the first time "in-vivo", a comparison with the "real" length of the vessel will be performed using as "gold standard" an intra-coronary guide-wire with radiopaque markers at fixed and known distance one from the other along its distal part.

Inclusion Criteria:

Clinical

• Age > 18 years.

• Ability to give informed consent.

• Clinical evidence of coronary artery disease:

  • recent (< 72 hours) acute myocardial infarction,
  • stable angina with documented positive stress test,
  • unstable angina with documented ischemia (positive ECG or troponin test or documented positive stress test).

Angiographic

• Eligibility for PCI in at least one de-novo stenosis in a native coronary artery, after the index angiogram.
• Planned PCI according to a previous coronary angiogram.

Exclusion Criteria:

Clinical

• Pregnancy.
• Chronic or acute renal failure (serum creatinine > 1.8 mg/dL or hemodialysis).
• Urgent procedure (a procedure carried out before the next referring day, for example for acute myocardial infarction, unstable angina refractory to medical therapy or cardiogenic shock).
• Contraindications or known hypersensitivity to contrast media.
• Enrollment in another study protocol.

Angiographic

• Significant left main coronary artery disease.
• PCI for a total occlusion of a major coronary vessel (LAD, LCX or RCA).
• Extensive thrombotic burden in a coronary lesion (thrombus grade 3/4).
• TIMI flow <3 distal to the lesion.