The Effect of Morning vs Evening Aerobic Exercise Training on Cardiac Remodeling and Function Improvement in Patients After ST Elevation Myocardial Infarction

Cardiovascular disease (CVD) remains the first cause of mortality worldwide. More than 30% of CVD-connected fatalities are ascribed to ST-segment Elevation myocardial infarction (STEMI). There is strong and consistent evidence that aerobic exercise after a STEMI improves overall and cardiovascular-related mortality. Aerobic exercise (AE) acts in key mechanisms of cardiac remodeling and function improvement after STEMI, thus contributing both to prevent or postpone harmful adaptations, and even to recover from negative alterations caused by cardiac ischemia. However, the time of day to exercise for STEMI patients' optimal cardiac benefits is currently unknown.

The circadian clock endows the host with temporal precision and robust adaptation to the surrounding environment. Almost all physiologic, metabolic and endocrine processes, including glycolysis, lipid and carbohydrate metabolism as well as cardiovascular function (heart rate, blood pressure) are influenced by the circadian clock. Recent investigations in rodents utilizing gain-of-function/loss-of-function models and in humans have identified Adverse cardiovascular events have day/night patterns is related to endogenous circadian clock control of platelet activation events. Several studies have also demonstrated the effect of AE at different times on blood pressure. Indeed, timing is critical in amplifying the beneficial impact of AE. However, these studies did not address cardiac structural remodeling or other CVD-related metabolic markers, it difficult to determine the physiological and structural effects of different time AE on cardiovascular health.

Thus, In this trial our aim is to assess, in patients who have had an STEMI, AE in which time of a day can give the best benefits to cardiac remodeling and function improvement.

Inclusion criteria

• Between 18 and 75-years-old;
• Typical symptoms of acute myocardial infarction within 24 hours, with ST segment elevation of ≥1mm in two consecutive leads on electrocardiogram
• After receiving complete revascularization treatment
• Cardiac function grading I to II without any other serious complications
• Left ventricular ejection fraction >30%
• Compliant with the guidelines of the American College of Cardiology/American Heart Association for participating in cardiac rehabilitation standards
• Signed written informed consent.

Exclusion criteria

• Patients with unstable angina
• severe symptomatic congestive heart failure detectable myocardial ischemia
• valvular disease requiring surgery
• severe ventricular arrhythmias
• severe concomitant life-threatening diseases such as cancer, and rheumatoid disease
• osteoarticular diseases that may affect the exercise process