Heart attack is one of the major cause of death in the modern society.  The local rate of survival from sudden cardiac arrest in non-hospital environment is 2.7%, much lower than the up to 20% reported in some Western cities. One reason for this discrepancy is the higher proportion of CPR (cardiopulmonary resuscitation) administered to victims of cardiac arrest by bystanders there. Only 30,000 Singaporeans know how to administer CPR. To equip more members of the public with this life-saving skill, the Singapore Heart Foundation has launched its own CPR certification programme. This will no doubt save many lives in the future.

However, even if the victims survive, a majority will suffer irreversible damage to the heart muscle due to hypoxia. Since cells lost from the heart do not grow back naturally, this leave the heart in a weakened and vulnerable state that may cause another serious condition — heart failure.

Now a team of scientists from Ben-Gurion University of the Negev in Beer-Sheva, Israel has developed a tissue-engineering technique, using the body as a ‘bioreactor,’ to create a ‘patch’ made from heart muscle that can be used to fix scarring left over from a heart attack. First, a biodegradable ‘scaffold’ is seeded with immature cells taken from the hearts of newborn rats. For 48 hours, the scaffold is exposed to a cocktail of growth-promoting chemicals in the laboratory and is then transplanted into a rat’s abdomen where it develops a network of blood vessels and muscle fibbers. After seven days the patch is removed and grafted onto the animal’s heart. A month later the patch has completely integrated itself into the heart, synchronizing its ‘beat’ with that of the surrounding tissue. Using the body as a bioreactor to engineer cardiac tissue with stable and functional blood vessel networks represents a significant improvement in cardiac patch performance over ex vivo (outside the body) methods currently used for patch production. The technique is also being developed for the repair of livers and bladders.