A specialist screening programme in Northern Ireland has led to the highest rate of identification of familial hypercholesterolaemia in the UK, according to the Belfast Trust. The condition, an inherited disorder causing high cholesterol, can lead to early heart attacks and heart disease if untreated.

Familial hypercholesterolaemia affects about one in 250 to 500 people in the population, but many remain undiagnosed. When someone is diagnosed, relatives are contacted and offered testing by specialist nurses covering all of Northern Ireland.

The Belfast Trust described FH as a silent condition. A spokesperson said the programme has achieved one of the highest rates of diagnosed cases in the world. Once diagnosed, patients are generally managed with standard cholesterol-lowering medications and periodic cholesterol checks.

Sandra McCartney, a mother of four from Londonderry, was diagnosed with FH after suffering a cardiac arrest while on holiday in Spain on New Year's Eve 2019. She was 59 at the time and had no prior knowledge of the condition.

McCartney collapsed, stopped breathing, and had no pulse for ten minutes before medics restored a normal heart rhythm with six defibrillator shocks and five shots of adrenaline. She was ventilated for 11 days and did not return home until February, using a wheelchair due to muscle wastage.

McCartney said she initially thought she had indigestion because of a hiatus hernia. After feeling acute pain and a tingling sensation in her right arm, she began drifting off until her husband woke her. A doctor told her she was having a major heart attack.

The experience left her with three cracked ribs from CPR and post-traumatic stress disorder. She now has an implantable cardioverter defibrillator fitted because she is at high risk of another cardiac arrest.

McCartney said she was fit and healthy before the event and never thought something like this could happen. She remains breathless from simple tasks but feels grateful to be alive.

Untreated FH carries significant risks. Fifty percent of men and 30 percent of women with untreated FH will develop coronary heart disease by age 55. If one parent has FH, there is a 50 percent chance their child will have it too.