Researchers in the U.K. have found that 20% of HCM gene carriers who do not show overt signs of HCM do show reduced blood flow to cardiac tissue.
Although the gene positive individuals lacked the characteristic left ventricular wall thickening of HCM, 1 of 5 patients who carried the HCM gene showed marked regional perfusion defects when compared to healthy individuals. Hence, the researchers concluded that a person who is gene positive for the disease may show reduced cardiac perfusion before they develop hypertrophy.
The study compared 50 patients who carried the HCM gene but had no signs of left ventricular hypertrophy to 28 healthy individuals. Both groups underwent Cardiac MRI testing.
The researchers theorize that perfusion mapping may be a useful way to identify HCM gene carriers who will go on to develop the disease.
To read about more early signs of HCM click here
and to read the findings of another study describing reduced cardiac volume in gene positive people, click here
An article entitled Psychosocial Impact of a Positive Gene Result for Asymptomatic Relatives at Risk of Hypertrophic Cardiomyopathy was published in this week’s Journal for Genetic Counseling.
The article focuses on the motivation for and the impact of HCM genetic testing on family members. The 32 participants in the study all encouraged family members to undergo genetic testing with the hope that the knowledge gained would benefit family members down the line. However, the study found that the psychological impact of a positive result, in the absence of overt disease, was highly variable. Some gene positive individuals perceived that they had an absolute risk of developing HCM, with substantial detriment to their lifestyle choices, while others were not at all affected by the result and made no lifestyle changes.
Continue reading “Continuing Genetic Counseling Helpful for Silent HCM Gene Carriers”
A study published today by Dr. Carolyn Ho, of Boston’s Brigham and Women’s Hospital, and colleagues, including Australia’s Christopher Semsarian, found that there are several factors which appear to stand out in young people who later go on to develop HCM.
The children/adolescents/young adults who participated in the study all carried at least one gene associated with HCM, and were members of families with strong histories of HCM. None of the 38 young people had clinical manifestations of HCM at the beginning of the study period, while 4 went on to develop HCM by the end of the study. In collecting the data analyzed in the study, the test results of the 4 individuals with HCM were compared to the 34 individuals that did not have HCM at the end of the study.
The factors associated with the development of overt HCM, as identified by the researchers, were: abnormal left ventricular relaxation and higher ejection fraction, EKG changes, longer mitral valve leaflets, higher NT-proBNP concentrations and troponin values.
In the conclusion, the authors acknowledged the need for further research and investigation in order to better understand the natural course and evolution of the disease.