Angiogram of Healthy Heart
Photograph by SPL/Photo Researchers, Inc.
The picture of health, an angiogram of a human heart shows blood vessels in sharp detail. To take an angiogram, or arteriogram x-ray, doctors must first inject the patient with a special opaque dye that allows a clear view of the heart's blood vessels, including the large left and right coronary arteries. Narrowed arteries indicate the presence of coronary artery disease. Blockages of either of the coronary arteries could lead to a heart attack. Such x-rays help doctors determine a course of treatment.
Inside the Heart
Photograph by Lennart Nilsson
Tissue-paper thin but tough, the valves of the human heart open and close to pump 6 quarts (0.9 liters) of blood a day through 60,000 miles (97,000 kilometers) of vessels. That's equivalent to 20 treks across the United States from coast to coast. The heart is a magnificent machine when it's in good working order. But coronary heart disease is the number one killer of American men as well as women, resulting in 500,000 deaths in the United States and killing 7.2 million people worldwide each year.
Photograph by Bruce Dale
At Houston's Ben Taub Hospital, careful—and quick—steps are taken to prep a donor heart for transport and transplantation. To preserve the harvested heart, a member of the transplant team flushes it with a cooling solution that slows its metabolic rate. Doctors have a narrow window of only four to six hours to get the heart into the waiting recipient before it is no longer viable.
Artificial Heart Implantation
Photograph by Robert Clark
Artificial heart implantation at the Berlin Heart Institute: Deft hands work to save the life of a critically ill cardiac patient at Germany’s Berlin Heart Institute. Doctors replaced the 62-year-old man's unhealthy heart with a CardioWest artificial heart during a four-hour procedure. The polyurethane heart—a temporary fix—will keep him alive until a well-matched human heart becomes available.
Photograph by George Steinmetz
Martti Tenhu, chief medical examiner in Helsinki, Finland, illustrates the differences between a normal human heart and one enlarged by alcoholism and high blood pressure. Covered in scar tissue, the enlarged organ is nearly twice the normal size. Such alcoholic cardiomyopathy weakens the heart so that it is unable to pump blood adequately.
Doctor With Stethoscope
Photograph by Jodi Cobb
Using well-trained listening skills, Charles Smith, an oncologist at Rappahannock General Hospital in Kilmarnock, Virginia, uses a stethoscope to hear the sounds in a cancer patient's chest. The highly sensitive—and versatile—instrument allows doctors to detect normal and abnormal sounds in such organs and vessels as the heart, lungs, arteries, and intestines.
Photograph by Scott Camazine/Phototake
Cause for concern is apparent in the chest x-ray of an 82-year-old cardiac patient. Pneumonia in his right lung can be seen as clearly as the pacemaker implanted to regulate the rhythm of his heart. Pneumonia is a common hospital-acquired infection.
Photograph by Michael Nichols
Wired for broadcasting in real time, a participant in the landmark Minnesota Study of Twins Reared Apart transmits electrocardiograph (EKG) readings to researchers via a portable monitor. The noninvasive procedure records electrical changes in the heart that can indicate the health of the organ or the presence of heart disease.
Heart Surgery Patient
Photograph by Robert Clark
Shortly after receiving an artificial heart, patient Siegfried Streiter takes a turn on a monitored cycle at Germany's Berlin Heart Institute. Such activity not only helps patients gain strength, it also allows physical therapists to assess their post-operative condition and outline an exercise program for home.
Photograph by Joy Tessman
There's nowhere to go but up for a runner following a railroad track toward California mountains. Although doctors recommend regular exercise to maintain a healthy heart, long-term athletic training comes with risks. Swimmers, cyclists, rowers, and distance runners are among those in danger of developing "athlete's heart," or hypertrophic cardiomyopathy, an abnormal thickening in the walls of the heart that can bring about sudden death.
National Geographic Channel
Wednesdays at 9P and 9:30P
Meet a group of backwoods Alabama geniuses who tackle problems with hillbilly ingenuity.
Wednesdays at 10P and 10:30P
Travel across America with host John Bowler as he seeks out the weirdest inventions.
Fridays at 8P, 9P, and 10P et/pt
Get up close with some of the world's most fascinating underground communities, from gangs to cults to organized crime families.
National Geographic Magazine
Buried in the English countryside. Anglo-Saxon in origin. Who hid it and why?
There was only one way scientists could unlock the mystery of the famous iceman. Take away his ice.
As the global population soars toward nine billion by 2045, this corner of Africa shows what's at stake in the decades ahead.
Shop Our Space Collection
The updated companion book to Carl Sagan's Cosmos, featuring a new forward by Neil deGrasse Tyson is now available. Proceeds support our mission programs, which protect species, habitats, and cultures.