(P36) An Unusual Cause of Pediatric Sudden Cardiac Arrest

Chief Complaint : CC – 4 year old male presented by private vehicle to the ED with chief complaint of sudden cardiac arrest.

History of Present Illness : HPI – He was at the playground, nearby hospital when he suddenly passed out while being verbally disciplined by his father. The child started crying and quickly lost consciousness. CPR was promptly started and the boy was transported to our ED by private car. Time of transport was less than 5 minutes.
CPR was continued in our ED, while he was put on the monitor. The initial rhythm was ventricular fibrillation.Definitive airway and IV was established. Resuscitation was conducted according to PALS protocol. Patient weight according to Broslow tape was 20 kg. He was given 2 doses of IV epinephrine and was defibrillated with 50J. ROSC was obtained after total of 5 minutes. Epinephrine drip was started secondary to hypotension. IV Magnesium and Amiodarone were administered for suspected Torsades des Pointes. Patient was transported by advanced pediatric transport to the local Children’s Hospital.

Pertinent Physical Exam: INITIAL PE - GENERAL – patient unresponsive, Vital Signs: Temperature 36.2C, HR 0/ 100 with CPR, RR 20 bagged, BP – no pulse HEAD – atraumatic, ENT pupils 3 mm, symmetric, sluggishly reactive, no blood in oropharynx, no hemo-tympanum. CARDIO – no pulse, RESPIRATORY – symmetric breath sounds while bagged, ABDOMEN – soft, no bruising, MSK – no signs of trauma, EXTREMITIES – cool with sluggish >3 seconds capillary refill, SKIN – no rash or bruising, NEURO – unresponsive

Pertinent Laboratory Data: LABORATORY - CBG – pCO2=70/pH=6.9, HCO3=15, Lytes – Na 137, K 4.9, Cl 101, HCO3 17, BUN 16, Cr 0.59 Glucose 163, AG 19, Mg 2.9

Case Discussion: DISCUSSION - DIFFERENTIAL DIAGNOSIS of pediatric arrests – the most common causes are primary RESPIRATORY cause; Inborn cardiac defects, Rhythm disturbances, Metabolic, Sepsis, Ingestion, Accidental and Non-Accidental Trauma.

HOSPITAL COURSE - While in the PICU, Epinephrine drip was weaned off and patient was extubated 16 hours after admission. Patient was diagnosed with Familial Catecholaminergic Polymorphic Ventricular Tachycardia. 2D Echo was performed which showed normal anatomy with no shunts and normal EF and PA pressures. He underwent placement of AICD. Discharge EKG showed NSR with rate of 93 and normal ST segments, and normal T waves. Patient was discharged with normal neurologic exam. Factors which positively affected the patient outcome were 1;CPR in the field 2; quick transport 3; following PALS protocol 4; optimized management after ROSC

Familial Catecholaminergic Polymorphic Ventricular Tachycardia (FCPVT) occurs in the absence of structural heart disease and typically begins in childhood or adolescence. There may be FH of juvenile sudden death or stress induced syncope. There have been 2 genes identified: the cardiac ryanodine (AD) and calsequestrin 2 (AR). Both mutations appear to act by inducing diastolic Ca++ release from sarcoplasmic reticulum. The resulting intracellular Ca++ overload leads to delayed afterdepolarizations and triggered activity, which can induce VT or VF.
Clinical presentation – patients typically presents with syncope or cardiac arrest due to VT/VF or asymptomatic as a part of familial screening. Diagnosis – CPVT is diagnosed by an exercise stress test that shows increased frequency of non-sustained VT during exercise or recovery.
Acute Management – during VT/VT recommended treatment is according to PALS electrical cardio-version/defibrillation. Propranolol is used for acute suppression of recurrent polymorphic VT. AICD should be considered in severe cases.

Genetic Testing – Our patient underwent genetic testing which confirmed MONO-ALLELIC MUTATION OF RYR2 GENE!!

References and Acknowledgements (Optional): Up to Date