Functional Diagnostic Accuracy of Quantitative Flow Ratio in Tandem Lesions and Virtual Stenting

• General inclusion Criteria:

  1. Stable and unstable angina pectoris or secondary evaluation of stenosis after acute MI;
  2. Age > 18 years;
  3. Able to provide signed informed consent.

• Angiographic inclusion criteria:

  1. At least two localized lesions on the same coronary artery;
  2. More than 50% diameter stenosis (DS) estimated by QCA on each lesion;
  3. At least 10 mm relatively normal lumen (at most 20% DS) between two lesions;
  4. Reference vessel size > 2 mm in stenotic segment by visual estimate.

Exclusion Criteria:

• General exclusion criteria:

  1. Ineligible for diagnostic intervention or FFR examination;
  2. Myocardial infarction within 72 hours;
  3. Severe heart failure (NYHA≥III);
  4. S-creatinine>150µmol/L or GFR\<45 ml/kg/1.73m2;
  5. Allergy to contrast agent or adenosine;
  6. Factors that might substantially impact the angiographic image quality, e.g, frequent atrial premature beat or atrial fibrillation;

  7. Serious complications:

     1. Evidence of cardiac rupture;
     2. History of bleeding (intracranial hemorrhage, gastrointestinal bleeding, etc.);
     3. Acute or chronic blood system diseases, including hemoglobin \< 10 g / L, or platelet count \< 50 × 109 / L;
     4. Accompanied by other diseases might inducing life expectancy shorter than several months;
     5. History of severe renal insufficiency and hypohepatia (liver failure, cirrhosis, portal hypertension and active hepatitis)
     6. Aneurysm, arterial / venous malformation, aortic dissection;
  8. Cardiogenic shock or circulation capacity failure;
  9. Two-degree and more severe atrioventricular block, with no permanent pacemaker implanted;
  10. Pregnancy or lactation;
  11. The investigators believe that the treatment regimen may be detrimental to the patient or the enrollment of this subject may affect the specific assessment of the trial;

• Angiographic exclusion criteria:

  1. The interrogated stenosis is caused by myocardial bridge;
  2. Ostial lesions less than 3 mm to the aorta;
  3. Side branches of the bifurcation lesions with Median Classification of 111 or 101;
  4. Severe overlap or shorten of stenosis segment;
  5. Severe tortuosity of target vessel;
  6. Poor angiographic image quality precluding contour detection.