Cold salt water reduces damage in heart attack patients

Researchers in Lund, Sweden have released the results of a study showing that the amount of heart damage in heart attack patients whose body temperature was lower than 35˚C (95˚F) was reduced by more than one third after they were treated with balloon angioplasty to open their clogged heart vessel. The results are published in the scientific journal Circulation-Cardiovascular Intervention.

In order to reduce patient body temperature, cold salt water was infused through a vein in the arm into the body. At the same time, a cooling catheter was inserted through a vein in the groin.

"We are impressed by the powerful effect and believe that this treatment has the potential to be of great benefit to patients in the future," said David Erlinge, Professor of Cardiology at Lund University, Sweden.

Every year more than three million people around the world suffer the type of heart attack known in the scientific community as an acute myocardial infarction. These patients are at immediate risk in that a major part of the heart muscle may die, which could lead to the development of heart failure and early death.

After several years of studies, the researchers have developed a method for rapidly and safely cooling the patient to below 35˚C before opening the occluded vessel with balloon angioplasty.

The patient remains awake during the procedure and is cooled from the inside, which means that the heart is cooled much quicker than if attempted from the outside with cooling pads or blankets. The patient experiences very little discomfort and if the patient feels cold, he or she is warmed from the outside with a warmblanket.

"We as cardiologists have been very good at opening the occluded blood vessel but not at protecting the heart muscle itself. This new treatment gives hope of great benefit for patients with acute myocardial infarction," said Professor Erlinge.

The discovery has been made by Professor Erlinge's research group at the Department of Cardiology, Lund University, Skåne University Hospital along with his colleagues Dr Göran Olivecrona and Dr Matthias Götberg.

Besides the positive effect in reducing the amount of heart damage, a marked reduction in biomarkers for cardiac injury was also found in blood samples, which helps support the findings. There was also no increase in side effects in the patients who were cooled. The researchers are now planning a larger study called CHILL-MI.