Catecholaminergic polymorphic ventricular tachycardia

Catecholaminergic polymorphic ventricular tachycardia

Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a potentially life threatening cardiac channelopathy (disease of cardiac ion channel) with propensity for polymorphic (typically bidirectional) ventricular tachycardia with exercise or emotional stress. Various genotypes of CPVT have been described, ranging from CPVT1 to CPVT5 as per the Online Mendelian Inheritance in Man (OMIM) database. The first one to be described was CPVT1 with mutation in cardiac ryanodine receptor (RyR2). A review on CPVT by the author was published in Heart Rhythm in 2005 [1].

CPVT1

The gene responsible for CPVT1 is located on chromosome 1 (1q43). It is a mutation in the cardiac ryanodine receptor gene (RYR2). The inheritance pattern of CPVT1 is autosomal dominant [2].

CPVT2

CPVT2 is caused by mutation in the calsequestrin-2 gene (CASQ2) located on chromosome 1 (1p13). Autosomal recessive pattern of inheritance has been noted with CPVT2 [3].

CPVT3

CPVT3 has been mapped to chromosome 7 (7p22-p14). It is an early onset lethal form of CPVT [4]. Mutations have been documented in the TECRL gene [5].

CPVT4

The gene responsible for CPVT4 is located on chromosome 1 at 14q32.11 and it is the calmodulin gene CALM1 [6]. It is inherited in an autosomal dominant pattern [7].

CPVT5

CPVT5 is caused by triadin gene (TRDN) mutations located on chromosome 6 (6q22). The disorder can occur with or without associated muscle weakness [8]. CPVT5 is also transmitted in an autosomal recessive pattern [7]. Triadin is a protein of the calcium release complex.

A Pediatric and Congenital Electrophysiology Society multicenter, retrospective cohort study of CPVT patients diagnosed before the age of 19 years and their first-degree relatives has been published [8]. Genetic testing was done in 194 of the 236 subjects in the study during a follow up period ranging from 1.4 to 5.3 years. 60% had RyR2 associated CPVT1.

CPVT2 due to homozygous CASQ2 mutation was found only in 4 patients. All had history of life-threatening symptoms. Another family potentially affected with heterozygous CPVT2 included three subjects of which the proband had life threatening symptoms. Her relatives had exercise induced ventricular bigeminy. An unusual point noted in the study was that in one quarter of the symptomatic patients, cardiac events were precipitated by only normal wakeful activities.

References

1. Francis J, Sankar V, Nair VK, Priori SG. Catecholaminergic polymorphic ventricular tachycardia. Heart Rhythm. 2005;2:550-4.
2. Laitinen PJ et al. Mutations of the cardiac ryanodine receptor (RyR2) gene in familial polymorphic ventricular tachycardia. Circulation 103: 485 – 490, 2001.
3. Lahat H et al. A missense mutation in a highly conserved region of CASQ2 is associated with autosomal recessive catecholamine-induced polymorphic ventricular tachycardia in Bedouin families from Israel. Am. J. Hum. Genet. 69: 1378 – 1384, 2001.
4. Bhuiyan ZA et al. A novel early onset lethal form of catecholaminergic polymorphic ventricular tachycardia maps to chromosome 7p14-p22. J. Cardiovasc. Electrophysiol. 18: 1060 – 1066, 2007.
5. Devalla HD, Gélinas R, Aburawi EH, Beqqali A, Goyette P, Freund C, Chaix MA, Tadros R, Jiang H, Le Béchec A, Monshouwer-Kloots JJ, Zwetsloot T, Kosmidis G, Latour F, Alikashani A, Hoekstra M, Schlaepfer J, Mummery CL, Stevenson B, Kutalik Z, de Vries AA, Rivard L, Wilde AA, Talajic M, Verkerk AO, Al-Gazali L, Rioux JD, Bhuiyan ZA, Passier R. TECRL, a new life-threatening inherited arrhythmia gene associated with overlapping clinical features of both LQTS and CPVT. EMBO Mol Med. 2016 Dec 1;8(12):1390-1408.
6. Nyegaard M et al. Mutations in calmodulin cause ventricular tachycardia and sudden cardiac death. Am. J. Hum. Genet. 91: 703 – 712, 2012.
7. Carlo Napolitano, Silvia G Priori, Raffaella Bloise. Catecholaminergic Polymorphic Ventricular Tachycardia. GeneReviews® [Internet]. Adam MP, Ardinger HH, Pagon RA, et al., editors. Seattle (WA): University of Washington, Seattle; 1993-2021.
8. Roux-Buisson N, Cacheux M, Fourest-Lieuvin A, Fauconnier J, Brocard J, Denjoy I, Durand P, Guicheney P, Kyndt F, Leenhardt A, Le Marec H, Lucet V, Mabo P, Probst V, Monnier N, Ray PF, Santoni E, Trémeaux P, Lacampagne A, Fauré J, Lunardi J, Marty I. Absence of triadin, a protein of the calcium release complex, is responsible for cardiac arrhythmia with sudden death in human. Hum Mol Genet. 2012 Jun 15;21(12):2759-67.
9. Roston TM, Yuchi Z, Kannankeril PJ, Hathaway J, Vinocur JM, Etheridge SP, Potts JE, Maginot KR, Salerno JC, Cohen MI, Hamilton RM, Pflaumer A, Mohammed S, Kimlicka L, Kanter RJ, LaPage MJ, Collins KK, Gebauer RA, Temple JD, Batra AS, Erickson C, Miszczak-Knecht M, Kubuš P, Bar-Cohen Y, Kantoch M, Thomas VC, Hessling G, Anderson C, Young ML, Choi SHJ, Cabrera Ortega M, Lau YR, Johnsrude CL, Fournier A, Van Petegem F, Sanatani S. The clinical and genetic spectrum of catecholaminergic polymorphic ventricular tachycardia: findings from an international multicentre registry. Europace. 2018 Mar 1;20(3):541-547.