OI & the Heart
Interview with Céu Barreiros, Cardiopneumologist
About the heart
As most of you will probably know, OI being a connective tissue (collagen) disorder, other parts of the body than bone can be affected. Collagen type 1 is present in different parts of the cardiovascular system, including what we call the fibrous skeleton of the heart, its valves, interventricular septum, aorta, and most other arteries, so it could be reasonable to think that collagen Type I abnormalities could also affect the heart. Although cardiovascular involvement in OI seems to be relatively rare, several cases that appear to be related to the underlying connective tissue disorder, have been reported. Most are related to abnormalities in the left-sided cardiac valves (aortic and mitral), the aortic root and ascending aorta.
Even though in most cases this is usually a progressive condition, there are also descriptions of rare cases of sudden death in asymptomatic subjects due to left ventricular rupture, aortic dissection and heart valves incompetence. Also we could think, that the reduced amount of collagen type 1 that is seen in OI could result in lower tensile strength and enlargement of both the atria and the ventricles, thus causing atrial arrythmias and heart failure, independent of other risk factors and at an earlier age than expected. However, once again, the risk to develop this or other arrhythmias has not been evaluated.
A recent (2015) review of the literature concluded that patients with OI seem to have increased risk of heart disease compared to healthy controls. However current information about heart disorders in OI children and adults has not been systematically approached.
About me and the Team
In the professional area, I’ve been working for 27 years as a Cardiac Physiologist at Santa Maria’s Hospital (SMH), in Lisbon. My relation and interest in OI began 21 years ago, when my younger daughter was born, with OI. Because of the lacking support, I was one of the founders of a National Association for OI in 2006 and later I got involved in OIFE. You can find our organization here: https://apoi.pt/
From the beginning APOI realized that cooperation with medical professionals was part of the process to reach our main goal of making lives of OI people better. In 2016 APOI established an internal department to help develop research studies, by helping OI people and families to come to the hospital (supporting travel and clinical costs, with volunteers help) and by helping researchers with the tasks they need (administrative, access to OI medical information, access to congresses etc.).
Cooperation at this level lead us to geneticists from SMH and start national research project to characterize the Portuguese OI population from a clinical and molecular point of view. This research was the result of an initiative of the association, and the trial design was planned with APOI, that is recognized as partner by the National Ethical Committee. Next step in this research was to move forward and “detail” the clinical characterization of OI, so we’ve invited other medical specialties to join and several “Sub-Studies” have started, one of them “OI & Heart”.
About our Study
This study aims to characterize the cardiovascular condition and evaluate the presence of potential subclinical cardiac disorders in osteogenesis imperfecta (adults and children):
- evaluate the risk of cardiovascular events on a population of OI
- correlate the mutation identified in each individual with the cardiovascular events found
- better understand the mechanisms of cardiac disorders in OI, to help doctors establish surveillance and preventions strategies, allowing patients to participate in their own health process and decision
Participants in the OI & Heart Sub-Study are invited to come to, either the Cardiology or the Paediatric Cardiology Department, in SMH (the major university hospital in the country), for 3 visits (baseline, one year and 5 years follow-up) were they have the following assessments: history and physical examination, echocardiography (with advanced features); ECG; ECG-Holter; and Ambulatory Blood Pressure Monitoring. If needed (after clinical assessment) other functional or angiographic tests may follow. Educational activities are also provided. When missing, collagen gene mutation and genetic evaluation will also be performed.
During their visits, families have the in-hospital support of an APOI volunteer and this allow us to control time so that all procedures can be scheduled or done during one single day. We have already included 66 patients. Round 50 have completed the one-year follow-up. We plan to include around 50 more patients in the coming months, but the COVID19 pandemic made us slow down recruitment.
Benefits and Impact
Several reports describe that there seems to be an increased incidence in cardiovascular events in OI but there are no recommendations regarding routine evaluation of this patients. More understanding of these problems is needed. Our goal is help to provide re commendations for routine cardiovascular follow-up of people with OI based on the characterization of cardiovascular conditions in this population.
Our aim is also that through health literacy, we can stimulate the self-management of cardiovascular risk factors and consequently increase the wellbeing, the perception of control and the overall autonomy of patients with OI. The correlation between the identified mutations and the clinical findings may also contribute to a better long-term cost-effectiveness management of the patients. The implementation of this study might also raise awareness and medical knowledge of OI among specialized health professionals.