Preexcitation syndrome patients have complaints of varying severity, depending on the underlying arrhythmia. Furthermore, signs and symptoms vary with the age of the affected individual. Newborns and toddlers may exhibit irritability, modified behavior, and indications of heart failure. Feeding is difficult for them, which may lead to failure to thrive if episodes are frequent and prolonged. Symptoms most often occur during a febrile illness.

An older individual will describe rapid palpitations, possibly accompanied by breathing difficulties and chest pain, even if coronary atherosclerosis is not clinically relevant at rest. Palpitations are usually regular (when they are due to a supraventricular orthodromic tachyarrhythmia conducted 1:1 to the ventricles via the accessory pathway), but may also be irregular (when the substrate is atrial fibrillation) and cause diminished physical effort tolerance. Atrial fibrillation is potentially life-threatening in these patients, leading to ventricular fibrillation [1]. Antidromic tachycardia is another possibility that clinically manifests as dizziness or syncope in the context of rapid, regular palpitations. Paroxysmal episodes can be followed by polyuria.

During the arrhythmia, the patient may be pale, exhibit diaphoresis, develop cool extremities, and display symptoms of low blood pressure. The venous pressure may be increased, leading to jugular turgescence. Hepatomegaly caused by stasis and pulmonary congestion manifesting as tachypnea are sometimes observed. The heart rate varies between 200 and 250 beats/minute. The person is hemodynamically stable unless associated abnormalities, such as Ebstein anomaly or hypertrophic cardiomyopathy exist [2]. The first condition is usually accompanied by cyanosis during the arrhythmic event.

• Pharyngitis

  Syndrome 804 Myocardial Contusion 810 Neck Injury by StrangulationHanging 818 Penile Shaft Fracture 820 Sting 822 Necrotizing Soft Tissue Infections 824 Neonatal Jaundice 830 Peripheral Neuropathy 836 Rectal Prolapse 840 Pertussis 844 Bartholin Abscess 134 Pharyngitis [books.google.com]

• Pertussis

  Parkinson Disease 802 Munchausen Syndrome 804 Myocardial Contusion 810 Neck Injury by StrangulationHanging 818 Penile Shaft Fracture 820 Sting 822 Necrotizing Soft Tissue Infections 824 Neonatal Jaundice 830 Peripheral Neuropathy 836 Rectal Prolapse 840 Pertussis [books.google.com]

• Pleural Effusion

  286 888 Pregnancy Trauma 898 Foreign Body Esophageal 902 Procedural Sedation 904 Pseudotumor Cerebri 910 Pulmonary Contusion 920 Purpura 926 Peritonsillar Abscess 928 Phalangeal Injuries Hand 934 Phenytoin Poisoning 940 Pityriasis Rosea 946 Red 948 Pleural [books.google.com]

• Failure to Thrive

  Feeding is difficult for them, which may lead to failure to thrive if episodes are frequent and prolonged. Symptoms most often occur during a febrile illness. [symptoma.com]

  Fred Ferri’s popular "5 books in 1" format provides quick guidance on menorrhagia, Failure to Thrive (FTT), Cogan’s syndrome, and much more. [books.google.com]

• Neonatal Jaundice

  Jaundice 830 Peripheral Neuropathy 836 Rectal Prolapse 840 Pertussis 844 Bartholin Abscess 134 Pharyngitis 850 Diverticulosis 858 Pneumothorax 876 286 888 Pregnancy Trauma 898 Foreign Body Esophageal 902 Procedural Sedation 904 Pseudotumor Cerebri 910 [books.google.com]

• Heart Disease

  Nineteen patients were free of associated heart disease. Average age for the group was 45 years (11 men and 11 women). Sustained atrial arrhythmias developed in four of 22 patients during MTT. All four were free of arrhythmia on subsequent MON. [ncbi.nlm.nih.gov]

  The CHD NSF UK Support Network Aims to support health care professionals in providing expert care to patients suffering form heart disease. A Yahoo group, with joining instructions, post and read mail. [curlie.org]

  First Department of Cardiology, Silesian Medical School Silesian Center for Heart Disease Zabrze Poland [link.springer.com]

• Meningism

  Ferri’s popular "5 books in 1" format provides quick guidance on short QT syndrome, microscopic polyangiitis, fungal meningitis, and much more. This medical reference makes the answers you need even easier to find - anytime, anywhere. [books.google.com]

The clinical evaluation may describe muscle weakness, suggesting a glycogen-storage illness, mental retardation in Danon disease, or macroglossia and hepatomegaly, indicators of Pompe disease. The blood workup should include the evaluation of electrolytes, such as potassium, calcium and magnesium. Screening for drugs, especially digoxin, is also important in cases where clinical judgement dictates, as they may act as precipitants for the arrhythmia. A thyroid panel can diagnose hyperthyroidism, another tachycardia trigger.

The main tool used to establish the preexcitation syndrome diagnosis is the 12-lead electrocardiogram. The QRS complex may be narrow, wide, or can change morphology in cases where there are multiple accessory pathways. Its aspect can also change if intermittent preexcitation exists. Preexcitation alternans is characterized by the alternation of a delta wave QRS complex with a normal one, whereas in concertina preexcitation the degree of preexcitation varies from one complex to the other. Typically, preexcitation syndromes exhibit a diminished PR interval (below 0.12 sec) and the presence of a delta wave (broad upstroke of the R wave). The QRS duration is increased above 0.12 sec and repolarization abnormalities are present. In Lown-Ganong-Levine syndrome, the QRS complex has no abnormalities, but the PR interval is short. More detailed information is offered by a 252-lead electrocardiogram combined with computed tomography imaging [3] [4] or electrophysiological studies [5]. Atrial fibrillation in preexcitation syndrome patients may cause hemodynamic instability [6] and should be suspected if the electrocardiogram shows a rapid succession of bizarre, shape changing complexes in a young individual [7]. The location of the accessory pathway is suggested by the lead that contains the maximally preexcited complexes [8].

An echocardiogram is needed in order to evaluate the presence of an Ebstein abnormality, hypertrophic cardiomyopathy, coronary sinus diverticula, L-transposition of the great vessels or atrial and ventricular septal defects. Parietal motion may be depressed during the acute arrhythmic episode, but should normalize when the rhythm returns to normal.

In cases where the arrhythmia has a short duration, a variety of recording devices, such as Holter monitors or implantable loop recorders can be used in order to diagnose it.

• Short PR Interval

  Wolff-Par·kin·son-White syn·drome ( wūlf park'in-son wīt ), [MIM*194200] an electrocardiographic pattern sometimes associated with paroxysmal tachycardia; it consists of a short PR interval (usually 0.1 second or less; occasionally normal) together with [medical-dictionary.thefreedictionary.com]

  The classic electrocardiogram in Wolff-Parkinson-White (WPW) syndrome is characterized by a short PR interval and prolonged QRS duration in the presence of sinus rhythm with initial slurring. [ncbi.nlm.nih.gov]

  Short PR interval. Normal QRS complex. Norma T wave. [en.my-ekg.com]

• Prominent A-Wave

  Other conditions that produce prominent R waves in V1 include right bundle branch block and left ventricular preexcitation, which is preceded by a short PR interval. [web.archive.org]

  R wave in V1-3 (mimicking posterior infarction). [litfl.com]

• Electrical Alternans

  alternans by a normal QRS amplitude T wave inversion common ST segment depression Treatment of orthodromic AVRT Treatment of AVRT is based on the presence of haemodynamic instability e.g. hypotension, altered mental state, or pulmonary oedema. [litfl.com]

• Pleural Effusion

  286 888 Pregnancy Trauma 898 Foreign Body Esophageal 902 Procedural Sedation 904 Pseudotumor Cerebri 910 Pulmonary Contusion 920 Purpura 926 Peritonsillar Abscess 928 Phalangeal Injuries Hand 934 Phenytoin Poisoning 940 Pityriasis Rosea 946 Red 948 Pleural [books.google.com]

• HLA-B5

  There was an increased frequency of HLA-A9 and HLA-B5 (P 0.026 and 0.0092) in the investigated population as a whole. [ncbi.nlm.nih.gov]

• HLA-A9

  There was an increased frequency of HLA-A9 and HLA-B5 (P 0.026 and 0.0092) in the investigated population as a whole. [ncbi.nlm.nih.gov]

• HLA-A3

  The participation of HLA-A3 antigen was significantly less among patients (P 0.03), while HLA-B14 antigen was not found in patients with preexcitation. [ncbi.nlm.nih.gov]

• HLA-DR7

  Within 10 HLA-DR locuses, HLA-DR7 antigen was rather more frequently present, although this was not statistically significant (P 0.173). [ncbi.nlm.nih.gov]

1. Sethi KK, Dhall A, Chadha DS, Garg S, Malani SK, Mathew OP. WPW and preexcitation syndromes. J Assoc Physicians India. 2007;55:10-15.
2. Gollob MH, Green MS, Tang AS, et al. Identification of a gene responsible for familial Wolff-Parkinson-White syndrome. N Engl J Med. 2001;344(24):1823-1831.
3. Shah A, Hocini M, Haissaguerre M, Jais P. Non-invasive mapping of cardiac arrhythmias. Curr Cardiol Rep. 2015;17(8):60.
4. Ramanathan C, Jia P, Ghanem RN, Ryu K, Rudy Y. Activation and repolarization of the normal human heart under complete physiological conditions. Proc Nat Acad Sci USA. 2006;103:6309–6314.
5. Calkins H, Sousa J, el-Atassi R, et al. Diagnosis and cure of the Wolff-Parkinson-White syndrome or paroxysmal supraventricular tachycardias during a single electrophysiologic test. N Engl J Med. 1991;324(23):1612-1618.
6. Mark DG, Brady WJ, Pines JM. Preexcitation syndromes: diagnostic consideration in the ED. Am J Emerg Med. 2009;27(7):878-888.
7. Fengler BT, Brady WJ, Plautz CU. Atrial fibrillation in the Wolff-Parkinson-White syndrome: ECG recognition and treatment in the ED. Am J Emerg Med. 2007;25(5):576-583.
8. Arruda MS, McClelland JH, Wang X, et al. Development and validation of an ECG algorithm for identifying accessory pathway ablation site in Wolff-Parkinson-White syndrome. J Cardiovasc Electrophysiol. 1998;9(1):2-12.