Long QT syndrome diagnosed in two sisters with propionic acidemia: a case report

Abstract

Propionic acidemia (PA) is a rare autosomal recessive metabolic disorder caused by deficiency of the mitochondrial enzyme propionyl-CoA carboxylase (PCC). This disorder mostly progresses with episodes of metabolic acidosis. Cardiomyopathy is among the cardiac complications known to occur during metabolic decompensation episodes. However, several recent papers emphasized the association of PA and long QT syndrome (LQTS) which may lead to extremely serious and fatal consequences. In this report, we describe two sisters with PA who have prolonged QT duration that were incidentally detected in an outpatient setting. LQTS was verified by electrocardiogram, stress test and 24 h rhythm holter monitoring. By this report, we want to emphasize the importance of early diagnosis of LQTS in asymptomatic patients with PA to prevent fatal complications.

Understanding the Pathogenesis of Cardiac Complications in Patients with Propionic Acidemia and Exploring Therapeutic Alternatives for Those Who Are Not Eligible or Are Waiting for Liver Transplantation

“…No patients showed ventricular arrhythmias or cardiac events [7]. Another paper described the use of propranolol in two sisters with PA and prolonged QTc [102].…”

Finding the Middle Ground with the Clinical Laboratory’s Role in SARS-CoV-2 Genomic Surveillance

“…U.S. genomic surveillance of this kind has been primarily a public health program supported by federal and/or state money ( 10 , 11 ). However, at least in the early days of the pandemic, SARS-CoV-2 genome sequencing was largely supported by academic and private institutions that took it upon themselves to perform SARS-CoV-2 NGS via much of their own preexisting infrastructure, including analysis pipelines and funding sources ( 12 ).…”

Cardiac Complications in Patients with Propionic Acidemia

“…Although no life-threatening arrhythmias were detected, we think that ventricular arrhythmias could be the responsibility of the symptoms of the patient. Recently, Duras et al et al described two sisters with PA who have prolonged QT duration that was incidentally detected in an outpatient setting 34 .…”

“…The mainstay of therapy in LQTS is the prophylactic, regular and uninterrupted use of beta-blockers 34,62,63 . The international LQTS registry has produced a series of observational research studies demonstrating a reduced risk among those who take beta-blockers.…”

“…The international LQTS registry has produced a series of observational research studies demonstrating a reduced risk among those who take beta-blockers. This treatment is recommended for patients diagnosed as LQTS who are asymptomatic with QTc ≥470 ms and symptomatic for syncope or documented ventricular tachycardia/ ventricular fibrillation 34,62,63 . Propranolol (2-4 mg/kg/day) has been shown to be effective in suppressing recurrent cardiac events.…”