A heart attack occurs when the flow of blood to the heart is blocked, most often by a build-up of fat, cholesterol and other substances, which form a plaque in the arteries that feed the heart (coronary arteries). The interrupted blood flow can damage or destroy part of the heart muscle. A heart attack, also called a myocardial infarction, can be fatal, but treatment has improved dramatically over the years. It's crucial to call 911 or emergency medical help if you think you might be having a heart attack.
Irises are classified as being one of six colors: amber, blue, brown, gray, green, hazel, or red. Often confused with hazel eyes, amber eyes tend to be a solid golden or copper color without flecks of blue or green typical of hazel eyes. Blue eyes have a low level of pigment present in the iris.
Eye color is the result of variations in the amount of melanin, a pigment found in the front part of the iris of the eye. The lack of this pigment results in blue eyes, some pigment gives green and lots of pigment gives brown eyes. So light brown eyes just have a bit less melanin than darker brown eyes. All of the different shades of eye color happen the same way. Blue-green eyes have an amount of melanin between green and blue, hazel eyes have an amount of pigment between green and brown, etc.