- Permanent atrial fibrillation (HP:0004754): Atrial fibrillation (AF) that cannot be successfully terminated by cardioversion, and longstanding (more than 1 year) AF, where cardioversion is not indicated or has not been attempted, is termed permanent. Evidence: PCS. Frequency: 3/11. (PMID:20560207)
- Cardiac arrest (HP:0001695): An abrupt loss of heart function. Evidence: TAS. (OMIM:613485)
- 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: 5/10. (PMID:20560207)
- Reduced left ventricular ejection fraction (HP:0012664): A diminution of the volumetric fraction of blood pumped out of the ventricle with each cardiac cycle. Evidence: PCS. Frequency: 0/9. (PMID:20560207)
- Early young adult onset (HP:0025708): Onset of disease at an age of greater than or equal to 16 to under 19 years. Evidence: PCS. Frequency: 1/2. (PMID:20560207)
- Congestive heart failure (HP:0001635): The presence of an abnormality of cardiac function that is responsible for the failure of the heart to pump blood at a rate that is commensurate with the needs of the tissues or a state in which abnormally elevated filling pressures are required for the heart to do so. Heart failure is frequently related to a defect in myocardial contraction. Evidence: PCS. Frequency: 3/9. (PMID:20560207)
- 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: 11/11. (PMID:20560207)
- 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: 10/12. (PMID:20560207)
- Torsade de pointes (HP:0001664): A type of ventricular tachycardia characterized by polymorphioc QRS complexes that change in amplitue and cycle length, and thus have the appearance of oscillating around the baseline in the EKG. Evidence: PCS. Frequency: 1/11. (PMID:20560207)
- Autosomal dominant inheritance (HP:0000006): 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 heterozygotes. In the context of medical genetics, an autosomal dominant disorder is caused when a single copy of the mutant allele is present. Males and females are affected equally, and can both transmit the disorder with a risk of 50% for each child of inheriting the mutant allele. Evidence: PCS. (PMID:20560207)
- Atrioventricular block (HP:0001678): Delayed or lack of conduction of atrial depolarizations through the atrioventricular node to the ventricles. Evidence: PCS. Frequency: 1/9. (PMID:20560207)
- Pulmonary embolism (HP:0002204): An embolus (that is, an abnormal particle circulating in the blood) located in the pulmonary artery and thereby blocking blood circulation to the lung. Usually the embolus is a blood clot that has developed in an extremity (for instance, a deep venous thrombosis), detached, and traveled through the circulation before becoming trapped in the pulmonary artery. Evidence: PCS. Frequency: 1/9. (PMID:20560207)
- Neonatal onset (HP:0003623): Onset of signs or symptoms of disease within the first 28 days of life. Evidence: PCS. Frequency: 1/2. (PMID:20560207)
These phenotypes are associated with the disease long QT syndrome 13 (OMIM:613485).