Case 22: Paroxysmal Supraventricular Tachycardia with Left Bundle Branch Block Aberrancy

A 7-week-old male infant with pneumonia of the right lower lobe, confirmed to be COVID positive, experienced frequent episodes of paroxysmal supraventricular tachycardia. He was admitted to the Pediatric Cardiology Department due to a heart rate of 270 bpm. Tachycardia ceased upon intravenous injection of Adenosine, but reoccurred within 1–2 min. The administration of Amiodarone 5 mg/kg/min for 24 h, followed by 15 mg/kg/min, in combination with Propranolol 1.5 mg/kg successfully maintained the normal sinus rhythm. Following the completion of the injectable treatment, oral medication was administered. The recommended dosage was 6 mg/kg/day of Amiodarone in combination with 1.5 mg/kg/day of Propranolol. The TSH and FT4 levels were within normal range. Echocardiography revealed a left ventricle of normal size, but with mild systolic dysfunction due to frequent episodes of tachycardia. The ejection fraction was measured 45–50%. Additionally, there was a patent foramen ovale of 2.6 mm and a patent ductus arteriosus with a diameter of 1.3 mm at the pulmonary end. The administration of Ceftriaxone at a dosage of 100 mg/kg/day for a duration of 7 days resulted in a positive improvement of the lung function. The discharge treatment consisted in Amiodarone 2 × 16 mg/day and Propranolol 3 × 3 mg/day (Figs. 28.1, 28.2, 28.3, 28.4, 28.5, 28.6, 28.7, 28.8, 28.9, 28.10, 28.11, 28.12, 28.13, 28.14, 28.15, 28.16, 28.17, 28.18, 28.19, 28.20, 28.21, 28.22, 28.23, 28.24, 28.25, 28.26, 28.27, and 28.28).