- Juvenile onset (HP:0003621): Onset of signs or symptoms of disease between the age of 5 and 15 years. Evidence: PCS. Frequency: 1/1. (PMID:30790670)
- Ventricular fibrillation (HP:0001663): Uncontrolled contractions of muscles fibers in the left ventricle not producing contraction of the left ventricle. Ventricular fibrillation usually begins with a ventricular premature contraction and a short run of rapid ventricular tachycardia degenerating into uncoordinating ventricular fibrillations. Evidence: PCS. Frequency: 4/6. (PMID:27861123)
- Cardiac arrest (HP:0001695): An abrupt loss of heart function. Evidence: PCS. Frequency: 3/3. (PMID:27861123)
- Paroxysmal ventricular tachycardia (HP:0004751): Episodes of ventricular tachycardia that have a sudden onset and ending. Evidence: PCS. Frequency: 1/1. (PMID:30790670)
- Prolonged QTc interval (HP:0005184): A longer than normal interval (corrected for heart rate) between the Q and T waves in the heart's cycle. Prolonged QTc can cause premature action potentials during late phase depolarizations thereby leading to ventricular arrhythmias and ventricular fibrillations. Evidence: PCS. Frequency: 0/1. (PMID:30790670)
- Polymorphic ventricular tachycardia (HP:0031677): A type of ventricular tachycardia that is characterized by variable QRS complexes within each lead (i.e., QRS complexes may be different from beat to beat). Evidence: PCS. Frequency: 1/1. (PMID:30790670)
- Bidirectional ventricular tachycardia (HP:0034040): Bidirectional ventricular tachycardia (BDVT) is a regular ventricular tachyarrhythmia (VT) with two different QRS morphologies alternating at a rate typically between 140 and 180 bpm. Evidence: PCS. Frequency: 1/1. (PMID:30790670)
- Childhood onset (HP:0011463): Onset of disease at the age of between 1 and 5 years. Evidence: PCS. Frequency: 1/3. (PMID:27861123)
- Young adult onset (HP:0011462): Onset of disease at the age of between 16 and 40 years. Evidence: PCS. Frequency: 2/3. (PMID:27861123)
- Premature ventricular contraction (HP:0006682): Premature ventricular contractions (PVC) or ventricular extrasystoles are premature contractions of the heart that arise in response to an impulse in the ventricles rather than the normal impulse from the sinoatrial (SA) node. Evidence: PCS. Frequency: 1/1. (PMID:30790670)
- Prolonged QT interval (HP:0001657): Increased time between the start of the Q wave and the end of the T wave as measured by the electrocardiogram (EKG). Evidence: PCS. Frequency: 3/3. (PMID:27861123)
- Autosomal recessive inheritance (HP:0000007): A mode of inheritance that is observed for traits related to a gene encoded on one of the autosomes (i.e., the human chromosomes 1-22) in which a trait manifests in individuals with two pathogenic alleles, either homozygotes (two copies of the same mutant allele) or compound heterozygotes (whereby each copy of a gene has a distinct mutant allele). Evidence: PCS. (PMID:27861123)
- Palpitations (HP:0001962): A sensation that the heart is pounding or racing, which is a non-specific sign but may be a manifestation of arrhythmia. Evidence: PCS. Frequency: 1/1. (PMID:30790670)
- Syncope (HP:0001279): A transient loss of consciousness (i.e., characterized by a rapid onset, a short duration, and a spontaneous and complete recovery) due to cerebral hypoperfusion. Evidence: PCS. Frequency: 2/4. (PMID:30790670;PMID:27861123)
- Ventricular tachycardia (HP:0004756): A tachycardia originating in the ventricles characterized by rapid heart rate (over 100 beats per minute) and broad QRS complexes (over 120 ms). Evidence: PCS. Frequency: 3/3. (PMID:27861123)
- Sudden death (HP:0001699): Rapid and unexpected death. Evidence: TAS. (OMIM:614021)
These phenotypes are associated with the disease catecholaminergic polymorphic ventricular tachycardia 3 (OMIM:614021).