Effects of coronary artery disease and percutaneous intervention on the cardiac metabolism of nonesterified fatty acids and insulin: Implications of diabetes mellitus

• Published in: Journal of internal medicine Vol. 265; no. 6; pp. 689 - 697
• Main Authors: Jaumdally, R. J., Lip, G. Y. H., Patel, J. V., MacFadyen, R. J., Varma, C.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.06.2009; Blackwell
• Subjects: Aged; Angioplasty, Balloon, Coronary; Aorta - metabolism; Biological and medical sciences; Blood Glucose - metabolism; Body Mass Index; Cardiology. Vascular system; Coronary Angiography; Coronary Artery Disease - complications; Coronary Artery Disease - metabolism; Coronary Artery Disease - therapy; Coronary heart disease; coronary intervention; diabetes; Diabetes Mellitus, Type 2 - complications; Diabetes Mellitus, Type 2 - metabolism; Diabetic Angiopathies - etiology; Diabetic Angiopathies - metabolism; fatty acid; Fatty Acids, Nonesterified - metabolism; Female; General aspects; Heart; Humans; insulin; Insulin - metabolism; intracardiac; Male; Medical sciences; Middle Aged; Myocardium - metabolism; Risk Factors; Endocrinopathy; Heart; Pancreatic hormone; Angioplasty; intracardiac; Diabetes mellitus; Instrumentation therapy; fatty acid; Lipids; Cardiovascular disease; Free fatty acid; Metabolism; Fatty acids; Coronary heart disease; Insulin; Percutaneous route; Medicine; coronary intervention; Circulatory system; diabetes
• ISSN: 0954-6820; 1365-2796; 1365-2796
• DOI: 10.1111/j.1365-2796.2009.02072.x

. Background.  Nonesterified fatty acids (NEFA) and insulin have been implicated in the pathogenesis of diabetes mellitus (Type 2 diabetes) and coronary artery disease (CAD). We hypothesized that intracardiac levels of insulin and NEFA within the aortic root, coronary sinus and systemic venous levels would be different in patients with coronary atherosclerosis and/or diabetes. We also studied the metabolic cardiac response following percutaneous coronary intervention (PCI). Methods.  A total of 67 subjects (42 males; mean age 60 ± 11 years) were recruited, of which three groups were identified: Group I – those with no CAD or Type 2 diabetes (n = 17); Group II – those with CAD but no Type 2 diabetes (n = 40); and Group III – patients with Type 2 diabetes and CAD (n = 10). Of the whole cohort, 34 patients (51%) proceeded to PCI. NEFA and insulin levels were analysed using enzymatic colorimetric and a monoclonal immuno‐autoanalyser techniques, respectively. Subsequently, fractional extraction (FFE) of both variables was calculated. Results.  Nonesterified fatty acids and insulin concentrations were lower in the aortic root versus coronary sinus (both P < 0.05). FFE of NEFA was 2× higher in Group I (P < 0.01) with a sevenfold reduction in insulin FFE in Group III. Following PCI, systemic NEFA levels increased significantly (P < 0.05) with no significant change seen within the coronary sinus (P = NS), whilst a reduction in insulin concentrations at all three sites was observed (all P < 0.01). No significant difference in FFE of NEFA was seen after PCI when comparing Groups II and III. There was a drop in insulin extraction in Group II (nondiabetic subjects, from 12% to −4%, P = 0.04), compared with an increase seen in Group III (Type 2 diabetes patients, from −4% to 3%, P = 0.03). Conclusion.  There is an intracardiac gradient of NEFA and insulin in Groups I–III. Cardiac NEFA metabolism was higher in those with mild CAD compared with those with obstructive CAD whereas intracardiac insulin extraction was lower in Group III (diabetic) patients. PCI was associated with a systemic rise in NEFA, with a reduction in insulin levels and cardiac utilization, but these effects were blunted in diabetic patients.