title: A high carbohydrate meal yields a lower ischemic threshold than a high fat meal in patients with stable coronary disease.
abstract: OBJECTIVE
  To assess the ischemic threshold and stress-induced left ventricular dysfunction after high fat (HFM) and high carbohydrate (HCM) meals in patients with stable coronary disease.
  
  
  METHODS
  Twelve patients (68 ± 7 years) underwent stress (treadmill exercise testing) echocardiography after fasting (8h), after HFM and HCM (2h). Time to 1mm ST-segment depression (time to 1mm) and stress wall motion score index (WMSI) were evaluated. Before eating and just before exercise testing glucose, insulin, triglycerides, total cholesterol and FFA levels were measured.
  
  
  RESULTS
  Results are expressed as medians (Q1-Q3). HFM did not affect exercise variables compared to fasting, whereas HCM reduced the ischemic threshold [time to 1mm from 376 (343-493) to 297 (180-420) s, p = 0.003]. Compared to fasting [1.47 (1.31-1.66)], stress WMSI was higher after HCM [1.56 (1.44-1.69)] (p = 0.04) but not after HFM [1.56 (1.30-1.63)]. Glycemia and insulinemia were significantly higher after HCM, compared to fasting and HFM.
  
  
  CONCLUSIONS
  In patients with coronary disease, exercise testing after a high carbohydrate meal results in a lower ischemic threshold and greater ischemia magnitude. Conversely, compared to fasting, a high fat meal does not induce additional detrimental effects. Hyperglycemia and hyperinsulinemia were the only metabolic determinants identified as potential metabolic mechanisms of this phenomenon.
authors.affiliation: Clinical Cardiology, Heart Failure Unit, Istituto Scientifico H San Raffaele, Milano, Italy. gabriele.fragasso@hsr.it
authors.forename: Gabriele
authors.initials: G
authors.lastname: Fragasso
authors.forename: Chiara
authors.initials: C
authors.lastname: Montano
authors.forename: Guido
authors.initials: G
authors.lastname: Lattuada
authors.forename: Anna
authors.initials: A
authors.lastname: Salerno
authors.forename: Altin
authors.initials: A
authors.lastname: Palloshi
authors.forename: Giliola
authors.initials: G
authors.lastname: Calori
authors.forename: Livio
authors.initials: L
authors.lastname: Luzi
authors.forename: Gianluca
authors.initials: G
authors.lastname: Perseghin
authors.forename: Alberto
authors.initials: A
authors.lastname: Margonato
mesh_terms: D000368:Aged; D001786:Blood Glucose / Q000378:metabolism; D002784:Cholesterol / Q000097:blood; D004040:Dietary Carbohydrates / Q000008:administration & dosage* / Q000493:pharmacokinetics; D004041:Dietary Fats / Q000008:administration & dosage* / Q000493:pharmacokinetics; D004452:Echocardiography; D016552:Ergometry; D005080:Exercise Test; D005230:Fatty Acids, Nonesterified / Q000097:blood; D005260:Female; D038321:Glycemic Index; D006801:Humans; D007328:Insulin / Q000097:blood; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000000981:diagnostic imaging / Q000378:metabolism / Q000503:physiopathology; D014280:Triglycerides / Q000097:blood; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging / Q000378:metabolism / Q000503:physiopathology
chemical_list: D001786:Blood Glucose; D004040:Dietary Carbohydrates; D004041:Dietary Fats; D005230:Fatty Acids, Nonesterified; D007328:Insulin; D014280:Triglycerides; D002784:Cholesterol