Impact of Acute Insulin Resistance on Myocardial Blush in Non- Diabetic Patients Undergoing Primary Percutaneous Coronary Intervention
Condition: Insulin Resistance and PCI
MeSH terms: Insulin Resistance
Study type: Observational

Summary: 
      Full myocardial reperfusion with restoration of coronary microcirculatory function (CMF) is a
      therapeutic goal in ST-segment elevation myocardial infarction (STEMI).1 Despite the success
      of primary percutaneous coronary intervention (pPCI), it is not achieved in 30% to 50% of
      patients.2,3 Insulin resistance (IR) as a part of metabolic syndrome is an important risk
      factor for the development of cardiac and vascular impairments and carries ominous prognosis
      in the setting of acute myocardial infarction.4 As a part of metabolic syndrome, IR is
      associated with myocardial and microvascular injury after STEMI in clinical studies. As
      phenomenon per se, independent of other components of metabolic syndrome, IR was related to
      ischemic myocardial injury after elective PCI.5

      Recently, IR in the early phase of acute coronary syndrome in non-diabetic patients, assessed
      by the homeostatic model assessment (HOMA) index, was established as an independent predictor
      of in-hospital mortality. This "acute" IR is a part of the acute glycometabolic response to
      stress, can be transient and can occur even in patients without chronic glycometabolic
      derangements.6

      Acute IR comprises acute hyperglycemia and/or acute hyperinsulinemia; Hyperglycemia has the
      prognostic relevance of hyperinsulinemia in STEMI patients and its relationship with coronary
      flow are less well evaluated.it also acknowledged direct acute negative cardiovascular
      effects as it is contributing to incomplete myocardial reperfusion and CMF impairment. The
      prognostic relevance of hyperinsulinemia in STEMI patients and its relationship with coronary
      flow are less well evaluated and acknowledged.7,8 Myocardial blush was first defined by
      Arnoud van't Hof etal . It is a qualitative visual assessment of the amount of contrast
      medium filling a territory supplied by a pericardial coronary artery.9 Myocardial blush grade
      is a valuable tool for assessing coronary microvasculature and myocardial perfusion in
      patients undergoing coronary angiography and angioplasty.

      Reduced myocardial blush grade identifies patients at higher risk who need more aggressive
      treatment both during the procedure to improve myocardial perfusion and later for secondary
      prevention.10

      We postulate that IR can occur in the early post pPCI period as a dynamic phenomenon even in
      non-diabetic patients, and be related to the development of microvascular injury. We have
      defined myocardial blush as a marker of coronary microvascular function, Accordingly, we have
      evaluated IR in relation to myocardial blush in non-diabetic STEMI patients treated by pPCI.
      as a primary end-point. The residual ST-segment elevation, post-TFC%; and MACE were secondary
      end points. The HOMA index is a simple and inexpensive marker of IR primary used in chronic
      states. It was recently validated against euglycemic hyperinsulinemic clamp in STEMI patients
      as feasible for assessing IR during myocardial infarction and therefore used in the current
      study.11
    

Detailed description: 
      Myocardial blush grade is valuable tool for assessing coronary microvasculature and
      myocardial perfusion in patients undergoing coronary angiography and angioplasty and its
      reduction identifies patients at high risk. In this study we investigate the association of
      acute insulin resistance with myocardial blush grade and outcome in non-diabetic patients
      with ST-segment elevation myocardial infarction (STEMI).
    

Intervention name(s): PCI
Intervention type(s): Device
Intervention description(s): Acute Insulin Resistance on Myocardial Blush in Non- Diabetic Patients Undergoing Primary Percutaneous Coronary Intervention
Other intervention name(s): primary Insulin resistance
Intervention MeSH terms: Insulin
Observational model: Other
Time perspective: Cross-Sectional
Sampling method: Non-Probability Sample
Study population: 
        240 non-diabetic patients with acute STEMI of both sexes and different ages selected from
        cardiology department in Assiut University Hospital who underwent primary percutaneous
        coronary intervention (PCI) between first of May 2018 and first of May 2019.