Heart arrhythmia could be a common medical condition occurring in people with MELAS syndrome, according to a recent case study report from researchers in Arkansas, Ohio and Texas. The recently published report, titled “Arrhythmia as a cardiac manifestation in MELAS syndrome” appeared in the journal Molecular Genetics and Metabolism Reports.
MELAS (mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes) syndrome is a genetic condition characterized by damaged mitochondria due to DNA mutations. Mitochondria are the cell’s power supply, generating energy in the form of adenosine triphosphate (ATP). According to the National Institutes of Health, mitochondrial disorders such as MELAS syndrome affect an estimated 1 in every 4,000 people — and currently have no cure.
Symptoms of MELAS syndrome can include difficulty breathing, vomiting, extreme fatigue, abdominal pain, and muscle weakness. Muscle spasms, diabetes, and heart and kidney problems can occur.
People with the condition may also suffer from stroke and dementia due to lactic acidosis caused by deficient mitochondria. Lactic acid builds up when cells use energy, but lactic acidosis occurs when lactic acid increases faster than it can be removed.
The case study report, authored by Tamara Thomas of the Arkansas Children’s Hospital, in Little Rock, and colleagues, described a 44-year old woman with MELAS syndrome who had a history of strokes that started at age 32. A cardiac team evaluated her and found a left ventricular hypertrophy (thickening of the muscle wall of the left chamber of the heart) and atrial tachycardia. Tachycardia is a faster than normal heart rate.
The authors concluded: “In summary, this is the unique case of a 44-year old female with a genetic diagnosis of MELAS syndrome with the associated cardiac manifestations of left ventricular hypertrophy and atrial tachycardia. This case demonstrates both the spectrum of associated cardiac disease in MELAS syndrome and the genetic component, and the potential association with subclinical atrial arrhythmias may advocate for routine ambulatory heart rate monitoring in this cohort of patients.”
Heart conditions may be common in people with the mitochondrial disorder, MELAS syndrome. The authors recommend that clinicians regularly monitor heart problems in people who have MELAS syndrome.