Vascular Interaction With Age in Myocardial Infarction

The body produces a natural compound, nitric oxide (NO), which is known to improve the elasticity of blood vessels effect cardiac function and play a role in the remodeling process after a heart attack. The primary source of NO is one of the amino acids that the body uses to form new proteins, L-Arginine; although many individuals with heart disease also take medicines to increase the concentrations of NO such as nitroglycerine. The VINTAGE-MI trial is intended to investigate wether supplementation of the bodies supply of NO with oral administration of L-Arginine will improve the functional recovery of older patients who have recently suffered their first heart attack.

BACKGROUND:

As we age, both our blood vessels and heart muscle naturally become stiff and loose their ability to flex as the heart beats and blood pressure changes. This is believed to worsen both blood vessel and cardiac function in older individuals. The stiffened tissue is likely to be less able to adapt to the stresses and remodeling that occur after a heart attack (myocardial infarction) because the loss of functional heart tissue predisposes the heart to poor function and the hearts blood vessels undergo various changes in order to increase the supply of blood to the damaged areas.

DESIGN NARRATIVE:

VINTAGE-MI is a randomized, double blind study enrolling patients who have recently suffered their first heart attack. There are two recruitment clinics within the Johns Hopkins University Network, the Johns Hopkins Hospital and the Hopkins Bayview Medical Center. Following preliminary testing to establish eligibility and baseline function of both the heart and blood vessels, study participants will be randomly assigned to receive either L-Arginine or a placebo pill which is identical except that it does not contain L-Arginine. These pills will be taken orally 3 times a day for 6 months. Participants will return to the clinic 1, 3, and 6 months after they begin taking their medication to have the same functional testing repeated.

Patients will have suffered their first acute Q-wave MI within 3 to 21 days with creatine kinase levels 3 times normal. All patients will have systolic blood pressure over 100 mmHg and the permission of their attending physician and the ability to give voluntary informed consent. Patients will be excluded if they have had a prior Q-wave infarction, present cardiogenic shock, unstable angina or non-cardiac disease limiting life expectancy to less than 1 year. Other exclusion criteria include significant kidney or liver disease, uncontrolled diabetes, or symptomatic cerebrovascular disease (such as stroke). Patients who have been previously shown to be non-compliant will be asked not to participate.