Severe left ventricular dysfunction following short‐term high fat feeding in a canine model

Abstract

This study tested the effects of short‐term high fat feeding on left ventricular function. Experiments were conducted in 4 mongrel dogs at baseline (normal chow: 40/30/30 carb/fat/protein), and after 2 and 6 weeks of high fat feeding (30/50/20 carb/fat/protein). Each condition included an intravenous glucose tolerance test for metabolic assessment, along with cardiac magnetic resonance imaging (cMRI) to evaluate left ventricular (LV) volumes, mass, and myocardial deformation (by tissue tagging). Remarkably, 2‐wk of high fat feeding dramatically worsened (all p<0.05) LV ejection fraction (mean+SD;−11.8+6.6%), circumferential strain (CS,+4.6+1.7%), circumferential strain rate (CSR,+34.7+16.0%/s) and LV torsion (−4.3+2.0°), with no changes in LV mass, heart rate, or glucose tolerance. By week 6, LV end‐diastolic volume significantly increased above baseline (+9.3+7.7 mL), returning ejection fraction closer to its basal level (−3.2+1.9%), while CS, CSR, and torsion remained impaired. Mechanisms responsible for impaired cardiac function from a short period of fat feeding with a modest increase in body weight need to be further elucidated.Support: Heart and Stroke Foundation of Canada (MN), Branco Weiss Fellowship (JB), NIH DK27619, DK 29867.