Severe familial dilated cardiomyopathy in a young adult due to a rare LMNA mutation: a case report

Background: Familial dilated cardiomyopathy prognosis and disease progression vary greatly depending upon the type of genetic mutation. Family history and genetic testing are paramount in developing the best treatment plan for a patient. However, with rare or novel mutations, the significance may be unknown. Regarding this, the following case report highlights the importance of vigilance and suspicion when treating a patient with a variant of unknown significance. Additionally, it shows the importance of thoroughly investigating the family history of cardiovascular disease.

Case summary: A 25-year-old Caucasian male was found to have a right bundle branch block and dilated cardiomyopathy upon presentation to the emergency department. Later testing showed that the dilated cardiomyopathy was due to an incredibly rare lamin A/C (LMNA) gene mutation, R349L. Despite treatment with a maximum-tolerable medication regimen and an automatic implantable cardioverter-defibrillator, the patient continued to decline and required a heart transplant.

Discussion: This case provides more information on the severity of this specific LMNA mutation that has only been documented once before. Of note, the time from the initial emergency department visit to the heart transplant was approximately 2 years. Given the patient's young age and rapid disease progression, in addition to a strong family history of sudden cardiac death, the significance of this mutation should not be understated. The additional knowledge gained from this case report can be used to aid in timely interventions and prognosis evaluation.