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Sick sinus syndrome 1(SSS1)

MedGen UID:
325270
Concept ID:
C1837845
Disease or Syndrome
Synonyms: Sick sinus syndrome 1, autosomal recessive; SICK SINUS SYNDROME, CONGENITAL; SINUS BRADYCARDIA SYNDROME, FAMILIAL; SINUS NODE DISEASE, FAMILIAL, AUTOSOMAL RECESSIVE; SINUS RHYTHM, CONGENITAL ABSENCE OF
 
Gene (location): SCN5A (3p22.2)
 
Monarch Initiative: MONDO:0024562
OMIM®: 608567

Definition

The term 'sick sinus syndrome' encompasses a variety of conditions caused by sinus node dysfunction. The most common clinical manifestations are syncope, presyncope, dizziness, and fatigue. Electrocardiogram typically shows sinus bradycardia, sinus arrest, and/or sinoatrial block. Episodes of atrial tachycardias coexisting with sinus bradycardia ('tachycardia-bradycardia syndrome') are also common in this disorder. SSS occurs most often in the elderly associated with underlying heart disease or previous cardiac surgery, but can also occur in the fetus, infant, or child without heart disease or other contributing factors, in which case it is considered to be a congenital disorder (Benson et al., 2003). Genetic Heterogeneity of Sick Sinus Syndrome Sick sinus syndrome-2 (SSS2; 163800) is caused by mutation in the HCN4 gene (605206). Susceptibility to sick sinus syndrome-3 (SSS3; 614090) is influenced by variation in the MYH6 gene (160710). Sick sinus syndrome-4 (SSS4; 619464) is caused by mutation in the GNB2 gene (139390). [from OMIM]

Additional description

From MedlinePlus Genetics
Sick sinus syndrome occurs most commonly in older adults, although it can be diagnosed in people of any age. The condition increases the risk of several life-threatening problems involving the heart and blood vessels. These include a heart rhythm abnormality called atrial fibrillation, heart failure, cardiac arrest, and stroke.

Sick sinus syndrome tends to cause the heartbeat to be too slow (bradycardia), although occasionally the heartbeat is too fast (tachycardia). In some cases, the heartbeat rapidly switches from being too fast to being too slow, a condition known as tachycardia-bradycardia syndrome. Symptoms related to abnormal heartbeats can include dizziness, light-headedness, fainting (syncope), a sensation of fluttering or pounding in the chest (palpitations), and confusion or memory problems. During exercise, many affected individuals experience chest pain, difficulty breathing, or excessive tiredness (fatigue). Once symptoms of sick sinus syndrome appear, they usually worsen with time. However, some people with the condition never experience any related health problems.

Sick sinus syndrome (also known as sinus node dysfunction) is a group of related heart conditions that can affect how the heart beats. "Sick sinus" refers to the sino-atrial (SA) node, which is an area of specialized cells in the heart that functions as a natural pacemaker. The SA node generates electrical impulses that start each heartbeat. These signals travel from the SA node to the rest of the heart, signaling the heart (cardiac) muscle to contract and pump blood. In people with sick sinus syndrome, the SA node does not function normally. In some cases, it does not produce the right signals to trigger a regular heartbeat. In others, abnormalities disrupt the electrical impulses and prevent them from reaching the rest of the heart.  https://medlineplus.gov/genetics/condition/sick-sinus-syndrome

Clinical features

From HPO
Atrioventricular block
MedGen UID:
13956
Concept ID:
C0004245
Disease or Syndrome
Delayed or lack of conduction of atrial depolarizations through the atrioventricular node to the ventricles.
Sick sinus syndrome
MedGen UID:
20749
Concept ID:
C0037052
Disease or Syndrome
An abnormality involving the generation of the action potential by the sinus node and is characterized by an atrial rate inappropriate for physiological requirements. Manifestations include severe sinus bradycardia, sinus pauses or arrest, sinus node exit block, chronic atrial tachyarrhythmias, alternating periods of atrial bradyarrhythmias and tachyarrhythmias, and inappropriate responses of heart rate during exercise or stress.
Sinus bradycardia
MedGen UID:
39316
Concept ID:
C0085610
Pathologic Function
Bradycardia related to a mean resting sinus rate of less than 50 beats per minute.
Prolonged QT interval
MedGen UID:
57494
Concept ID:
C0151878
Finding
Increased time between the start of the Q wave and the end of the T wave as measured by the electrocardiogram (EKG).
Ventricular escape rhythm
MedGen UID:
65423
Concept ID:
C0232216
Pathologic Function
A ventricular escape rhythm occurs whenever higher-lever pacemakers in AV junction or sinus node fail to control ventricular activation. Escape rate is usually 20-40 bpm, often associated with broad QRS complexes (at least 120 ms).
Absent P wave
MedGen UID:
324892
Concept ID:
C1837847
Finding
The P wave that normally precedes each QRS complex by a fixed PR interval of 120 to 200 milliseconds is not present.

Professional guidelines

PubMed

Kusumoto FM, Schoenfeld MH, Barrett C, Edgerton JR, Ellenbogen KA, Gold MR, Goldschlager NF, Hamilton RM, Joglar JA, Kim RJ, Lee R, Marine JE, McLeod CJ, Oken KR, Patton KK, Pellegrini CN, Selzman KA, Thompson A, Varosy PD
Circulation 2019 Aug 20;140(8):e382-e482. Epub 2018 Nov 6 doi: 10.1161/CIR.0000000000000628. PMID: 30586772
Deal N
Emerg Med Pract 2013 Sep;15(9):1-15; quiz 15-6. Epub 2013 Aug 10 PMID: 24044868
Perry JC, Garson A Jr
Adv Pediatr 1989;36:177-99. PMID: 2675568

Recent clinical studies

Etiology

Shi X, Shao X, Liu B, Lv M, Pandey P, Guo C, Zhang R, Zhang Y
Biochim Biophys Acta Mol Basis Dis 2020 Jul 1;1866(7):165757. Epub 2020 Mar 5 doi: 10.1016/j.bbadis.2020.165757. PMID: 32147422
Delise P, Sitta N, Zoppo F, Corò L, Verlato R, Mantovan R, Sciarra L, Cannarozzo P, Fantinel M, Bonso A, Bertaglia E, D'Este D
Ital Heart J 2002 Dec;3(12):715-20. PMID: 12611122
Hutter PA, Kreb DL, Mantel SF, Hitchcock JF, Meijboom EJ, Bennink GB
J Thorac Cardiovasc Surg 2002 Oct;124(4):790-7. doi: 10.1067/mtc.2002.120714. PMID: 12324738

Diagnosis

Hategan L, Csányi B, Ördög B, Kákonyi K, Tringer A, Kiss O, Orosz A, Sághy L, Nagy I, Hegedűs Z, Rudas L, Széll M, Varró A, Forster T, Sepp R
Int J Cardiol 2017 Aug 15;241:364-372. Epub 2017 Apr 20 doi: 10.1016/j.ijcard.2017.04.058. PMID: 28465117
Larsen BT, Maleszewski JJ, Edwards WD, Cooper LT Jr, Sobonya RE, Thompson VE, Duckett SG, Peebles CR, Simpson IA, Tazelaar HD
Circulation 2013 Jan 1;127(1):39-47. Epub 2012 Nov 26 doi: 10.1161/CIRCULATIONAHA.112.128900. PMID: 23183940

Therapy

Delise P, Sitta N, Zoppo F, Corò L, Verlato R, Mantovan R, Sciarra L, Cannarozzo P, Fantinel M, Bonso A, Bertaglia E, D'Este D
Ital Heart J 2002 Dec;3(12):715-20. PMID: 12611122

Prognosis

Shi X, Shao X, Liu B, Lv M, Pandey P, Guo C, Zhang R, Zhang Y
Biochim Biophys Acta Mol Basis Dis 2020 Jul 1;1866(7):165757. Epub 2020 Mar 5 doi: 10.1016/j.bbadis.2020.165757. PMID: 32147422
Larsen BT, Maleszewski JJ, Edwards WD, Cooper LT Jr, Sobonya RE, Thompson VE, Duckett SG, Peebles CR, Simpson IA, Tazelaar HD
Circulation 2013 Jan 1;127(1):39-47. Epub 2012 Nov 26 doi: 10.1161/CIRCULATIONAHA.112.128900. PMID: 23183940
Hutter PA, Kreb DL, Mantel SF, Hitchcock JF, Meijboom EJ, Bennink GB
J Thorac Cardiovasc Surg 2002 Oct;124(4):790-7. doi: 10.1067/mtc.2002.120714. PMID: 12324738

Clinical prediction guides

Shi X, Shao X, Liu B, Lv M, Pandey P, Guo C, Zhang R, Zhang Y
Biochim Biophys Acta Mol Basis Dis 2020 Jul 1;1866(7):165757. Epub 2020 Mar 5 doi: 10.1016/j.bbadis.2020.165757. PMID: 32147422
Hategan L, Csányi B, Ördög B, Kákonyi K, Tringer A, Kiss O, Orosz A, Sághy L, Nagy I, Hegedűs Z, Rudas L, Széll M, Varró A, Forster T, Sepp R
Int J Cardiol 2017 Aug 15;241:364-372. Epub 2017 Apr 20 doi: 10.1016/j.ijcard.2017.04.058. PMID: 28465117
Milano A, Vermeer AM, Lodder EM, Barc J, Verkerk AO, Postma AV, van der Bilt IA, Baars MJ, van Haelst PL, Caliskan K, Hoedemaekers YM, Le Scouarnec S, Redon R, Pinto YM, Christiaans I, Wilde AA, Bezzina CR
J Am Coll Cardiol 2014 Aug 26;64(8):745-56. doi: 10.1016/j.jacc.2014.05.045. PMID: 25145517

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