Background: Cardiomyopathies (CMs) are rare multifactorial diseases of the heart muscle. Neonatal forms present as a myocardial injury in the absence of primary valvular, great vessels or septal anomalies. Despite being uncommon diseases, CMs may lead to potentially severe sequelae and considerable risk of neonatal death. This study aimed to provide an overview of neonatal CM (NCM) and describe its aetiology, initial clinical findings, morbidity and mortality.
Methods: Retrospective observational study of all newborns diagnosed with CM admitted to the Neonatal Intensive Care Unit (NICU) of Centro Hospitalar Universitário de S. João, in Porto, Portugal, between 1997 and 2017. Data collected included demographic and perinatal information, clinical presentation, CM type and aetiology, treatments, complications and outcome.
Results: Twenty-eight newborns with CM diagnosis were selected: 26 neonates were considered to have primary CM forms and 2 secondary CMs. Of those 26 diagnosed with primary CMs, 16 had hypertrophic CM, 8 had dilated CM, and 2 had tachycardia-induced CM. Secondary CMs comprehended 1 case of infiltrative CM and another of CM due to corticosteroids toxicity. Cardiac murmur (57.1%) was the most common finding, followed by heart failure (HF, 28.6%), cyanosis (21.4%), arrhythmia and sepsis (17.9%, each), and hypertension (10.7%). Two newborns were placed on a heart transplant waiting list. Three neonates developed congestive HF and 1 had a sudden cardiac death event. A total of 4 (14.3%) newborns have deceased during the NICU stay. More than 90% of the neonates were prescribed more than one medicine at discharge.
Conclusion: NCMs require critical intensive care management. Unspecific symptoms characterise clinical findings. The majority of newborns have idiopathic primary CMs, but rare heterogeneous aetiologies may be the underlying cause in some cases. Thus, a multidisciplinary approach is mandatory.