Changes

:This article is from the National Heart, Lung, and Blood Institute<ref>National Heart, Lung, and Blood Institute [http://www.nhlbi.nih.gov/health/dci/Diseases/HeartAttack/HeartAttack_WhatIs.html]</ref>  See that web site for the figures that accompany the text.

:This article is from the National Heart, Lung, and Blood Institute<ref>National Heart, Lung, and Blood Institute [http://www.nhlbi.nih.gov/health/dci/Diseases/HeartAttack/HeartAttack_WhatIs.html]</ref>  See that web site for the figures that accompany the text.

A '''heart attack''' occurs when blood flow to a section of heart muscle becomes blocked. If the flow of blood isn’t restored quickly, the section of heart muscle becomes damaged from lack of oxygen and begins to die.

A '''heart attack''' occurs when [[blood]] flow to a section of [[heart]] muscle becomes blocked. If the flow of blood isn’t restored quickly, the section of heart [[muscle]] becomes damaged from lack of [[oxygen]] and begins to die.

Heart attack is a leading killer of both men and women in the United States. But fortunately, today there are excellent treatments for heart attack that can save lives and prevent disabilities. Treatment is most effective when started within 1 hour of the beginning of symptoms. If you think you or someone you’re with is having a heart attack, call 9–1–1 right away.

Heart attack is a leading killer of both men and women in the [[United States]]. But fortunately, today there are excellent treatments for heart attack that can save lives and prevent disabilities. Treatment is most effective when started within 1 hour of the beginning of symptoms. If you think you or someone you’re with is having a heart attack, call 9–1–1 right away.

== Overview ==

== Overview ==