Sprague-Dawley rats treated with isoprenaline at the age of 56 weeks. Rats maintained on either water (ISO-control, n = 5–9) or TMAO solution (ISO-TMAO, n = 7–10). T1 - metabolic and echocardiographic measurements, T2 - echocardiographic measurements, T3 - metabolic, echocardiographic and direct hemodynamic measurements (see also the study design, Figure 1). Creatinine clearance calculated as urine creatinine x urine output (ml/min)/plasma creatinine. LVEDV - left ventricle end diastolic volume, LVESV - left ventricle end systolic volume, SV – stroke volume, EF - ejection fraction, IVSs(d), intraventricular septum diameter during systole and diastole, respectively. LVEDP - pressure in the left ventricle during the end of diastole measured directly with a catheter, +dP/dt - maximal slope of systolic ventricular pressure increment, - dP/dt - maximal slope of diastolic ventricular pressure decrement. Values are means,± SD. P values by t-test or Mann-Whitney U test, except # - by log-rank test.