DCM is a condition which occurs when the heart becomes so enlarged that it is no longer able to pump blood efficiently. The condition affects 35 in every 100,000 people. Researchers in the United States have suggested in a recent study published in the journal Science that a defect in the gene phospholamban may trigger DCM. This gene plays a key role in regulating the flow of calcium through the heart, enabling it to beat effectively. The heart muscle contracts and relaxes when calcium is released from a reservoir inside into the muscle cell and then pumped back quickly. Scientists have discovered that some people with inherited DCM show a subtle mutation in their phospholamban gene. Patients with DCM may suffer with tiredness, and shortness of breath whilst exercising or even whilst resting. They may have heart palpitations and notice their ankles becoming swollen.
Scientists used tests on mice to determine if a defect in this gene is enough to trigger DCM. They found that a mouse with a defect on the phospholamban gene also suffered severe damage to its heart. Further laboratory tests also showed that this defect disrupts the calcium pump in heart muscle cells. Scientists also found that people with this defect would suffer a chronic malfunction of calcium regulation in their heart muscle. Over time this would lead to heart failure.
Christine Seidman, who led the study, said that the discovery has led to the question of whether heart failure can be prevented if calcium cycle can be restored in this type of defect. The scientists involved in the study believe that this study may help them understand more about heart failure and also in the development of new drugs to treat the condition.