Mono- Versus Dual antiPlatelet Therapy During 6-12 Months After New Generation Drug Eluting Stent Implantation
Condition: Gastrointestinal Injury; Ischemic Heart Disease
MeSH terms: Heart Diseases; Myocardial Ischemia; Coronary Artery Disease
Study type: Interventional
Phase: Phase 4

Summary: 
      Long-term DAPT is recommended after percutaneous coronary intervention (PCI) in patients with
      coronary artery disease. However, antiplatelet therapy may have adverse consequences, the
      most common of which is gastrointestinal mucosal injury with ulceration and bleeding. The
      extent to which an an abbreviated DAPT strategy reduces gastrointestinal mucosal injury has
      not been studied, principally due to the lack of sensitive, noninvasive measurements capable
      of detecting gastrointestinal injury.ANKON® magnetically controlled capsule endoscopy (AMCE)
      is a non-invasive, active controlled system which affords assessment of the stomach and
      entire small intestine.The current randomized study will assess gastrointestinal mucosal
      injury and bleeding via AMCE in patients on three different antiplatelet regimens and
      establish a gastrointestinal mucosal injury scoring system which may prove useful in guiding
      optimal antiplatelet agent usage after PCI.
    

Detailed description: 
      Dual antiplatelet therapy (DAPT) with aspirin and a platelet P2Y12 receptor inhibitor has
      become the cornerstone for secondary prevention of coronary artery disease. Long-term DAPT is
      recommended after percutaneous coronary intervention (PCI) in patients with coronary artery
      disease to prevent future thrombotic events arising from the stent or untreated coronary
      lesions. However, antiplatelet therapy may have adverse consequences, the most common of
      which is gastrointestinal mucosal injury with ulceration and bleeding. The frequency of
      gastrointestinal complications increases with the duration of DAPT. Studies in patients
      treated with current generation drug-eluting stents have demonstrated that shortened DAPT
      regimens reduce the risk of bleeding events with small ischemic risk. However, the optimal
      duration of DAPT is still controversial. The extent to which an an abbreviated DAPT strategy
      reduces gastrointestinal mucosal injury has not been studied, principally due to the lack of
      sensitive, noninvasive measurements capable of detecting gastrointestinal injury.

      Endoscopic examination of the gastric mucosa (gastroscopy) has high sensitivity and accuracy
      to detect gastrointestinal injury and bleeding. However, endoscopy is invasive and thus has
      no role in screening for sub-clinical gastrointestinal bleeding in patients undergoing PCI.
      Rather, endoscopy examinations are reserved for patients with active bleeding to identify the
      location of origin and etiology of the bleed. Moreover, gastroenterologists often refuse to
      perform gastroscopy in patients on DAPT given the risk of iatrogenic trauma with excessive
      hemorrhage. To minimize this risk, one or both antiplatelet agents often have to be
      discontinued for several days prior to the procedure, delaying the diagnosis while increasing
      the risk of stent thrombosis. Finally, upper endoscopy can only detect pathology related to
      the stomach and duodenum, as it does not visualize the remainder of the small intestine.

      ANKON® magnetically controlled capsule endoscopy (AMCE) is a non-invasive, active controlled
      system which affords assessment of the stomach and entire small intestine. In the AMCE
      procedure, the patient swallows a capsule containing an endoscope which is actively
      maneuvered via magnetic control in the stomach, and then passes through the gastrointestinal
      track until its ultimate excretion. AMCE has several advantages compared to standard
      endoscopy. AMCE is noninvasive, painless and convenient, and can be re-administered as
      necessary. Patient acceptance of AMCE is likely to be substantially higher than standard
      endoscopy as the procedure involves only swallowing a capsule endoscope, without anesthesia
      or recovery time. Compared to standard endoscopy, AMCE provides more comprehensive detection
      of gastrointestinal pathology as it visualizes not only the stomach and duodenum, but the
      entire small intestine. Finally, discontinuation of antiplatelet drugs during AMCE is not
      necessary. Because of these advantages, AMCE can be used for screening of gastrointestinal
      mucosal lesions prior to clinical bleeding, including early detection of small areas of focal
      and concealed bleeding. Detection of preclinical gastric ulcerations or bleeding may be
      useful in directing preventative measures, whether gastro-protective therapies or DAPT
      discontinuation. A large-scale, randomized trial has confirmed that the sensitivity and
      specificity of AMCE for the detection of focal lesions of the gastrointestinal tract is
      similar to standard endoscopy. However, the potential utility of AMCE in patients receiving
      antiplatelet therapy after PCI has not been reported.

      The current randomized study will evaluate AMCE as a tool to assess gastrointestinal mucosal
      injury and bleeding in patients on DAPT; evaluate the relative rates of gastrointestinal
      injury in patients on three different antiplatelet regimens; and establish a gastrointestinal
      mucosal injury scoring system which may prove useful in guiding optimal antiplatelet agent
      usage after PCI.
    

Intervention name(s): Aspirin + clopidogrel; Clopidogrel monotherapy; Aspirin monotherapy
Intervention type(s): Drug; Drug; Drug
Intervention description(s): After randomization(6 months±2 weeks after enrollment),receive aspirin 100mg/d + clopidogrel 75mg/d for an additional 6 months. The above treatments between 6 and 12 months are double-blinded.; After randomization(6 months±2 weeks after enrollment),receive clopidogrel 75mg/d + placebo (clopidogrel monotherapy group) for an additional 6 months. The above treatments between 6 and 12 months are double-blinded.; After randomization(6 months±2 weeks after enrollment),receive aspirin 100mg/d + placebo (aspirin monotherapy group) for an additional 6 months. The above treatments between 6 and 12 months are double-blinded.
Other intervention name(s): Clopidogrel + placebo; Aspirin + clopidogrel
Intervention MeSH terms: Aspirin; Clopidogrel
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary purpose: Treatment