Clinical Trial: Relationship Between Level of Hemoglobin A1c and Platelet Function in Patients Undergoing Cardiac Surgery

Study Status: Recruiting
Recruit Status: Recruiting
Study Type: Observational [Patient Registry]

Official Title: Relationship Between Level of Glycosylated Hemoglobin and Platelet Function in Patients Undergoing Coronary Artery Bypass Grafting

Brief Summary: The aim of this study is to evaluate whether increased level of hemoglobin A1c (HbA1c) correlates to higher level of platelet reactivity assessed by impedance aggregometry in patients with diabetes mellitus undergoing elective coronary artery bypass grafting (CABG).

Detailed Summary:

This study will be conducted at Cardiac Surgery Department, University Hospital Center Zagreb. It will be conducted in prospective observational fashion. Diabetic patients undergoing isolated, primary on-pump CABG will be consecutively recruited. Patients requiring urgent procedure will be excluded. Blood samples, both for conventional lab. findings (including HbA1c) and impedance aggregometry will be drawn prior to surgery and postoperatively on daily basis.

Cohort sample will be divided into two subgroups according to HbA1c level (Group 1 with HbA1c < 7% and Group 2 with HbA1c ≥ 7%, respectively). Respective subgroups will be compared for basic demographic data, laboratory findings including those obtained using platelet function testing, and for clinical outcomes, respectively.

Multiple-electrode aggregometry:

Whole blood aggregation will be determined using a new-generation impedance aggregometer (Multiplate analyzer; Roche Diagnostics). In brief, when platelets expose receptors on their surface they get activated and stick on the Multiplate sensor wires enhancing the electrical resistance between them. An increase in impedance is expressed in arbitrary area under the curve (AUC) units. Platelet aggregation is determined in response to stimulation with arachidonic acid (ASPI (aspirin-sensitive patients identification) test designed to evaluate the effect to acetylsalicylic acid (ASA)) and adenosine diphosphate (ADP) (ADP test designed to evaluate the effect of thienopyridines, such as clopidogrel).


Sponsor: Clinical Hospital Centre Zagreb

Current Primary Outcome: The level of preoperative HbA1c that will be a predictor of the higher prevalence of platelet resistance to the aspirin [ Time Frame: 4 days after surgery ]

Original Primary Outcome: Same as current

Current Secondary Outcome:

  • Differences in perioperative aspirin resistance (AUC, area under the curve) between patients with insulin-dependent diabetes mellitus and patients with non-insulin-dependent diabetes mellitus [ Time Frame: 4 days after surgery ]
  • Correlation between platelet ADP receptors reactivity (AUC) and the type of diabetes [ Time Frame: 4 days after surgery ]
  • Correlation of diabetes duration and platelet reactivity (AUC) [ Time Frame: 4 days after surgery ]
  • The prevalence of major adverse cardiovascular events (MAACE) in patients with HbA1c ≥ 7% [ Time Frame: 3 months after surgery ]
  • Postoperative thoracic drainage in patients with the appropriate glucose regulation (Hba1c<7%) [ Time Frame: within the first 5 days after surgery ]
  • Mortality [ Time Frame: 3 months after surgery ]
  • The level of HbA1c, that will represent the reliable predictor of platelet hyperreactivity and MAACE [ Time Frame: within the 3 months after surgery ]


Original Secondary Outcome: Same as current

Information By: Clinical Hospital Centre Zagreb

Dates:
Date Received: March 7, 2016
Date Started: February 2014
Date Completion: August 2016
Last Updated: March 19, 2016
Last Verified: March 2016