The Mariana Islands are shown, with the territory of Guam to the extreme south, and the Commonwealth of the Northern Mariana Islands (14 islands) to the north. Active volcanoes are shown with triangles. The Mariana Islands (also the Marianas) are a crescent-shaped archipelago comprising the summits of fifteen mostly dormant volcanic mountains in the western North Pacific Ocean, between the 12th and 21st parallels north and along the 145th meridian east.
People with congestive heart failure are often given pacemakers to help their hearts pump more efficiently. But doctors have been puzzled by about 40 percent of people given those devices who don't get any better. They often wind up in the hospital, or they die. Now researchers say they've got the problem figured out.
If you have second-degree heart block, you may need a pacemaker. A pacemaker is a small device that's placed under the skin of your chest or abdomen. This device uses electrical pulses to prompt the heart to beat at a normal rate.If you have third-degree heart block, you will need a pacemaker.In an emergency, a temporary pacemaker might be used until you can get a long-term device. Most people who have third-degree heart block need pacemakers for the rest of their lives.f you have third-degree heart block, you will need a pacemaker. In an emergency, a temporary pacemaker might be used until you can get a long-term device. Most people who have third-degree heart block need pacemakers for the rest of their lives.