Short-term effects of trans fatty acids from ruminant and industrial sources on surrogate markers of cardiovascular risk in healthy men and women: A randomized, controlled, double-blind trial.

Objective The aim of this study was to determine short-term effects of trans fatty acid (TFA) intake from ruminant and industrial sources on surrogate markers of cardiovascular risk in the context of a balanced diet with 30-36% of daily energy from fat. Design Prospective, randomized, double-blind, parallel-design study. Methods In this study, 142 healthy volunteers aged 45 to 69 years were randomly allocated to three different diets: either a diet enriched with 2% of daily energy intake from ruminant TFA (rTFA) or with industrial TFA (iTFA), or a diet without TFA (wTFA), for a duration of four weeks. The primary outcome parameter was endothelial function measured by brachial artery flow mediated dilation (FMD). Secondary outcome parameters included biomarkers for inflammation, coagulation and endothelial function and lipid profiles. One hundred and twenty-nine participants completed the study. Results Neither alpine butter with TFA from ruminant source nor margarine with industrially produced TFA showed significant effects on brachial artery FMD (FMD% differences: rTFA vs. iTFA 0.04 (95% confidence interval 0.91 to 0.98), rTFA vs. wTFA -0.98 (-2.00 to 0.04) and iTFA vs. wTFA -1.04 (-2.38 to 0.30). With rTFA, there was a small but significant increase of total cholesterol: rTFA over wTFA 1.04 (1.00 to 1.07 mmol/l) and LDL-cholesterol: rTFA over wTFA 1.08 (1.03 to 1.14 mmol/l) without concomitant increase of biomarkers for inflammation or coagulation. Conclusions Short-term intake of TFA at 2% of total daily energy intake from neither ruminant nor industrially produced sources does not have any negative impact on brachial artery FMD, inflammation and coagulation markers in healthy subjects.

Short-term high altitude exposure at 3454 m is well tolerated in patients with stable heart failure.

AIMS: High altitude exposure for the purpose of tourism is very popular in mountainous regions and is considered to be safe for patients with stable CAD and preserved LV function. The purpose of this study was to evaluate the haemodynamic response to exercise and electrical stability by Holter monitoring in patients with chronic heart failure (HF) and an EF <40%. METHODS AND RESULTS: We studied 29 HF patients with a peak VO2 >50% of the predicted (25 men, age 60.0 ± 8.9 years, EF 28.8 ± 5.4%) at 540 and 3454 m after an ascent using public transport. Assessments of exercise capacity (cardiopulmonary exercise test), haemodynamic response (inert gas rebreathing system), and susceptibility to arrhythmias (Holter ECG recording) were performed. None of the patients (19 with ischaemic heart disease, 11 with an implantable cardioverter defibrillator) had to return prematurely to the lowland site. Two patients presented symptoms of mild mountain sickness, and one patient developed a self-limited ventricular tachycardia during maximal exercise at high altitude. Mean peak VO2 at the lowland site was 18.5 ± 3.6 mL/min/kg and decreased by 22.2% (P < 0.001) at high altitude. Mean resting heart rate increased from 74.3 ± 12.3 to 83.3 ± 13.4 b.p.m., P < 0.001. No statistically significant difference in premature ventricular contractions (92 ± 150/h at 540 m vs. 111 ± 196/h at 3454 m, P = 0.284) was noted. CONCLUSION: Patients with stable chronic HF and a peak VO2 >50% of the predicted tolerate a short exposure to an altitude of 3454 m well, even during exercise. However, it cannot be excluded that the susceptibility to ventricular tachyarrhythmias during exercise is increased in some subjects.