Randomized Clinical Trial of Non-Surgical Reperfusion of the Coronary Arteries
Condition: Cardiovascular Diseases; Coronary Disease; Heart Diseases; Myocardial Infarction; Myocardial Ischemia
MeSH terms: Cardiovascular Diseases; Heart Diseases; Myocardial Infarction; Coronary Disease; Myocardial Ischemia; Infarction; Ischemia
Study type: Interventional
Phase: Phase 3

Summary: 
      To assess the effect of non-surgical reperfusion on infarct size in patients with acute
      myocardial infarction.
    

Detailed description: 
      BACKGROUND:

      Angiographic studies in the acute stage of myocardial infarction have shown complete
      occlusion in 75-85 percent and subtotal lesions in the remaining cases. Evidence for spasm in
      acutely occluded arteries has been reported. However, the majority of pathological as well as
      intraoperative examinations have yielded thrombotic material at the site of complete
      obstruction. Indirect evidence of thrombotic material was provided by successful
      intracoronary thrombolysis in 80 percent of infarct patients with complete obstruction. There
      could be causative relationships between spasm, intimal damage and coronary thrombosis.
      Selective applications of spasmolytic and/or thrombolytic substances into occluded vessels
      enabled high local concentrations with doses that caused little or no systemic effect.
      Angiographic verification of the results of this pharmacotherapy would help to clarify the
      role of spasm and thrombus in the pathogenesis of the acute coronary occlusion.

      Reperfusion in man has been achieved by coronary by-pass surgery in the acute stage of
      infarction. Follow-up angiography revealed significant improvement of left ventricular
      function. Intracoronary streptokinase infusion resulted in recanalization of acute coronary
      occlusion in 80 percent of cases within 20-30 minutes of infusion time. Reperfusion achieved
      by intervention angiography has been associated with improved local wall motion as well as
      improved left ventricular function. Improvement in left ventricular function depended on the
      duration of symptoms prior to reperfusion and on the presence or absence of collateral blood
      flow. Available data suggested that improvement was more likely to occur if reperfusion was
      achieved within 3-4 hours. However, since the majority of patients reached the hospital after
      greater than 4 hours of chest pain, study of functional changes following late reperfusion
      was of great practical significance.

      DESIGN NARRATIVE:

      The study was a randomized trial of myocardial reperfusion in acute myocardial infarction by
      selective intracoronary infusion of nitroglycerin and/or intracoronary infusion of
      streptokinase. The trial was single-blinded as to the interventional therapy; it was
      double-blinded as to the drug infused. The primary endpoint was the ejection fraction on the
      10th day of intervention. Patients were assigned to one of four treatment arms: an
      intracoronary infusion of streptokinase; an intracoronary infusion of nitroglycerin; combined
      infusions of nitroglycerin and streptokinase; a control group receiving conventional therapy
      without acute catheterization. All patients underwent anticoagulant therapy with intravenous
      heparin followed by warfarin for three months. Patients were followed for a minimum of two
      years.

      The study completion date listed in this record was obtained from the Query/View/Report (QVR)
      System.
    

Intervention name(s): nitroglycerin; streptokinase; heart catheterization
Intervention type(s): Drug; Drug; Procedure
Intervention MeSH terms: Streptokinase; Nitroglycerin
Allocation: Randomized
Masking: Double
Primary purpose: Treatment