Study on the prevention of sudden cardiac death

One of the focus points of Concor is the prevention of premature death in adults with congenital heart defects. The second most common cause of death –the first being heart failure– is sudden cardiac death. In the majority of cases, sudden cardiac death is caused by dangerous rhythm disorders in the chambers of the heart (ventricular fibrillation). When this happens, countless chaotic electrical currents go through the heart chambers, causing the heart to stop pumping. This is also called cardiac arrest. An implantable defibrillator (ICD) can detect this heart rhythm disorder and stop it with an electric shock. Yet, it is not known which patients should receive an ICD.

Recently, new guidelines were released that attempted to create some clarity in this issue. However, it is not yet evident whether these quidelines can actually select the right patients who need an ICD. Because of this, Concor researcher Jim Vehmeijer examined whether the recommendations in these guidelines are correct using data from Concor, Leuven (Belgium) and Toronto (Canada). Patients who died from sudden cardiac death were compared to control patients who were still alive at the same age. In the study, 35-40% of patients should have received an ICD according to these guidelines. Most of these patients would therefore not have received protection from sudden cardiac death, even with these new guidelines. In addition, about 15% of control patients should also have received an ICD according to the guidelines. This may cause unnecessary complications related to the implant surgery and the device itself.

Altogether, the ability of the guidelines to determine who will actually die from sudden cardiac death was mediocre.
In short, the guidelines are a step towards creating more clarity about which patients have a high risk of sudden cardiac death, and therefore should receive an ICD. However, more research on the matter is still required to refine this. Until that is achieved, it remains important to not only follow the guidelines, but also regard each patient individually.