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The NHLBI leads or sponsors studies for patients who have heart, lung, blood, or sleep-related diseases or disorders. Find studies for diseases and conditions and see if you or a loved one is eligible.
A conduction disorder, or heart block, is a problem with the electrical system that controls the heart’s rate and rhythm. This can cause the heartbeat to be too fast, too slow, or irregular.
Congenital Heart Defects
Congenital heart defects, or diseases, are problems with the heart's structure that are present at birth.
COPD, or chronic obstructive pulmonary disease, is a long-term condition that damages the lungs and blocks airflow into and out of the lunge. This makes it hard to breathe.
Coronary Artery Bypass Grafting
Coronary artery bypass grafting, sometimes called coronary artery bypass surgery or just bypass surgery, is a procedure to improve blood flow to the heart.
Coronary Heart Disease
Coronary heart disease is a common type of heart disease where the arteries of the heart cannot deliver enough oxygen-rich blood to the heart.
CPAP (continuous positive airway pressure) is a device that uses mild air pressure to keep the airways open while you sleep. It is often used to treat breathing problems during sleep.
Cystic fibrosis is an inherited condition that affects the body’s cells, tissues, and the glands that make mucus and sweat.