A high carbohydrate meal yields a lower ischemic threshold than a high fat meal in patients with stable coronary disease.
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.
Fragasso
Gabriele
G
Clinical Cardiology, Heart Failure Unit, Istituto Scientifico H San Raffaele, Milano, Italy. gabriele.fragasso@hsr.it
Montano
Chiara
C
Lattuada
Guido
G
Salerno
Anna
A
Palloshi
Altin
A
Calori
Giliola
G
Luzi
Livio
L
Perseghin
Gianluca
G
Margonato
Alberto
A
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
D001786:Blood Glucose; D004040:Dietary Carbohydrates; D004041:Dietary Fats; D005230:Fatty Acids, Nonesterified; D007328:Insulin; D014280:Triglycerides; D002784:Cholesterol