Results of Coronary Artery Bypass Grafting in Obese Patients
Condition: Chronic Ischemic Heart Disease; Obesity
MeSH terms: Heart Diseases; Myocardial Ischemia; Coronary Artery Disease
Study type: Observational

Summary: 
      This study is planned to assess the effect of obesity (BMI over 30 kg / m2) on hospital
      outcomes of isolated coronary artery bypass grafting in patients with chronic ischemic heart
      disease.
    

Detailed description: 
      This study is planned to assess the effect of obesity (BMI over 30 kg / m2) on hospital
      outcomes of isolated coronary artery bypass grafting in patients with chronic ischemic heart
      disease.

      It is planned to retrospectively enroll around 500 patients who underwent coronary artery
      bypass grafting for chronic ischemic heart disease at the Tomsk Research Institute of
      Cardiology. It is planned to develop a register of isolated coronary bypass grafting
      procedures, to conduct a comparative analysis of hospital results in obese patients (BMI more
      than 30 kg / m2) and without (BMI less than 30 kg / m2), to identify risk factors for adverse
      outcomes in patients of this group of patients.

      Planning methods:

        1. Clinical status of the patient: collection of complaints, medical history, physical
           examination, assessment of anthropometric indicators (measurement of body weight,
           height, BMI), and demographic indicators before and in the control period after surgical
           treatment.

        2. General clinical examination: standard 12-lead ECG, general urine analysis, general
           blood analysis, blood chemistry, coagulation, chest x-ray, ultrasound of the carotid and
           femoral arteries.

        3. Coronarography to assess the anatomy and condition of the coronary arteries.

        4. Echocardiography to assess the following parameters: mass of viable left ventricular
           myocardium; volumes of cardiac cavities; diameter of the mitral and tricuspid valve
           rings with the determination of regurgitation degree; the long axis of the ventricle;
           left ventricular ejection fraction; visualization of akinetic and hypokinetic
           myocardium; the presence of blood clots in the cavities of the heart; All surgical
           procedures will be performed via median sternotomy Intraoperative information will be
           collected from the anesthetic record, surgical notes and perfusion records.
           Intraoperative data collection will include total operative time, CPB time, cross-clamp
           time, intraoperative red blood cell transfusion (units), highest dose/agent used for
           intraoperative inotrope or vasopressor support. Intraoperative flowmetry of coronary
           grafts during coronary artery bypass grafting using the Medistim VeriQ System will be
           performed.

      Postoperative data will include valuation of following indicators: mortality (hospital
      mortality and death from any cause); neurological injury (TIA, stroke, delirium), acute
      kidney injury (creatinine level prior and 1 postoperative day, urine output-up to 24-48 h,
      renal replacement therapy (dialysis); time of mechanical ventilation; re-exploration for
      bleeding, tamponade or other reasons; postoperative transfusion (packed red blood cells,
      platelets, fresh frozen platelets, cryoprecipitate); postoperative myocardial infarction
      (electrocardiogram and troponins); inotropic support during 24-48 h (agent and dose (VIS));
      length of stay (intensive care unit and total hospital days).

      Structured collection of patient data will be performed in a database formed on the platform
      of the Microsoft Excel 2010 software (Microsoft Corp., USA). Statistical processing of the
      results will be carried out using the SPSS 23.0 for Windows software package (IBM Corp.,
      Armonk, NY, USA). The normality of the law of distribution of quantitative indicators will be
      checked using the Shapiro-Wilks criterion. Normally distributed parameters will be presented
      as mean value (M) and standard deviation (StD) in the form M ± StD; not normally distributed
      parameters will be presented as median (Me) and the 1st and 3rd interquantile intervals (Q25
      - Q75) in the form of Me [Q25; Q75]. Qualitative data will be described by the frequency of
      occurrence or its percentage. To find statistical dependences, to determine their strength
      and direction, the Pearson correlation coefficient (r) (for normally distributed parameters)
      and Spearman correlation coefficient (for for not normally distributed parameters and for
      qualitative indicators in the ordinal scale) will be calculated. Using logistic regression,
      significant predictors will be identified for the values of reverse remodeling in the long
      term after surgical treatment. When conducting a multivariate analysis of interconnections,
      first, by means of a univariate analysis, the main parameters that influence the studied
      value will be identified, then, based on the search for intergroup correlations, the signs
      that have a moderate or strong relationship will be eliminated, and multivariate modeling of
      the relationships will be performed.

      During the work, the methods of statistical analysis can be revised and (or) supplemented.
    

Intervention name(s): coronary artery bypass grafting
Intervention type(s): Procedure
Intervention description(s): Coronary artery bypass surgery is a surgical procedure to restore normal blood flow to an obstructed or stenotic coronary artery.
Other intervention name(s): CABG
Observational model: Case-Control
Time perspective: Retrospective
Sampling method: Non-Probability Sample
Study population: 
        Patients being living in Russian Federation (inc. ethnic minorities) with chronic ischemic
        heart disease and indications for cardiac surgery
      
Keywords: Chronic Ischemic Heart Disease; Obesity; coronary artery bypass grafting