• Most individuals under 60 with implanted pacemakers do not have a diagnosis that explains the cause of their disease.
• Around 15% of these patients have a direct genetic cause that would explain the need for pacemaker implantation, and an additional 30% have alterations in relevant genes.
• Genetic studies help diagnose the specific cause of the disease, allowing for better treatments and risk stratification of relatives.
Madrid, August 7, 2024.
Most young adults that have implanted pacemakers do not have a diagnosis that explains the cause for the need to implant this device that generates electrical impulses to maintain normal heartbeat. However, a new study led by cardiologist Juan Pablo Ochoa, researcher at the Spanish National Centre for Cardiovascular Research (Centro Nacional de Investigaciones Cardiovasculares, CNIC) and Scientific Director at Health in Code, and by Pablo Garcia-Pavia, cardiologist at the Puerta de Hierro Majadahonda University Hospital, leader of the Inherited Cardiomyopathies Group at CNIC, and leader of the Cardiovascular Disease Group at CIBER (CIBERCV), has determined that some very rare genetic variants increase the risk of suffering cardiac conduction disorders that require pacemaker implantation.
In fact, according to the study published in the JACC Clinical Electrophysiology journal, around 15% of patients have a direct genetic cause, i.e. a mutation in a gene is detected that can explain the need for pacemaker implantation by itself. Moreover, up to an additional 30% have alterations in genes considered relevant, which opens the possibility to further study this subject and advance in the determination of the genetic cause of this disease.
“When a clearly causal genetic mutation is detected, it is essential to determine the correct diagnosis. In some of these cases, we have found that these mutations correspond to diseases that can later manifest at the level of cardiac muscle, impairing its performance. In these cases, it is of great importance, because we can prevent these complications by providing early and suitable treatments”, stated Juan Pablo Ochoa, MD.
“Moreover, genetic testing is not only relevant to the patients, but also to their families. Since these mutations are inherited, it is possible to also test their relatives, particularly their offspring. Thus, we can find out who has or has not inherited the mutation and anticipate who is at risk of suffering the patient’s disease in the future”, explained Pablo García-Pavía, MD.
A unique study
The study “Rare genetic variants in young adults requiring pacemaker implantation” is the broadest study performed worldwide to date about the influence of genetics on cardiac conduction diseases, with the participation of 14 Spanish hospitals. Researchers performed genetic tests on 150 patients with cardiac conduction disorders of unknown cause who had a pacemaker implanted before age 60. By comparing the prevalence of rare genetic variants that could alter the function of relevant proteins in these subjects against a reference population (control subjects), these variants were observed to be more frequent in the patient group and to increase the risk of presenting with cardiac conduction disorders.
Based on the study’s results, it was concluded that genetic testing should be performed on any young patients (under age 60) who show cardiac conduction disorders of unknown cause and who require pacemaker implantation. This allows for better risk stratification and treatment of patients, as well as for adequate management of relatives.
The article can be viewed open-access at: link.
