The pacemaker may have one to three leads, depending on the type of pacemaker needed to treat your heart problem. There are different types of pacemakers: Single-chamber pacemakers use one lead in the upper chamber (atria) or lower chamber (ventricles) of the right side of the heart.
The MexicanâAmerican War, also known as the Mexican War, the U.S.âMexican War or the Invasion of Mexico, was an armed conflict between the United States of America and the United Mexican States from 1846 to 1848.
In response to a Mexican massacre of an American army detachment in disputed territory, the U.S. Congress declared war on May 13, 1846; Mexico followed suit on 23 May. The MexicanâAmerican War took place in two theatres: the western (aimed at California) and Central Mexico (aimed at capturing Mexico City) campaigns.