CPVT

File:ECG000032.jpg

The ECG of a patient with CPVT in rest is normal

File:ECG000033.jpg

The ECG of the same patient with CPVT during exercise. Asterisks mark polymorphic ventricular beats.

Catecholaminergic Polymorphic Ventricular Tachycardia is a congenital disease that leads to exercise induced ventricular arrhythmias and / or syncope and carries an increased risk of sudden death.

Characteristics of CPVT:

• The mean onset of arrhythmias is 7-9 years
• Absence of structural cardiac abnormalities
• Normal resting ECG
• Syncope during physical activity or emotional stress

Diagnosis

• The diagnosis is based on the patient's clinical history (dizziness or syncope induced by exercise or emotional stress and a family history containing syncope or sudden death in young relatives related to similar triggers) and reproducible ventricular arrhythmias during exercise testing. The complexity of these arrhythmias often increases with increasing work load, starting with Ventricular Premature Beats, and ending with bidirectional ventricular tachycardia to polymorphic ventricular tachycardia.
• Two genes have been linked to CPVT. Both lead to a defect in intracellular calcium metabolism:
  • the hRyR2 gene, coding for the cardiac ryanodine receptor: (OMIM™ link 180902) (50-55 % of patients)
  • the CASQ2 gene, coding for the calsequestrine protein: (OMIM™ link 114251) (1-2 % of patients)

Treatment[1]

• Beta-blockers
• ICD (Internal Cardioverter Defibrillator) implantation combined with beta-blockers in CPVT patients who survived a cardiac arrest or patients with syncope and/or documented sustained ventricular tachycardia despite beta-blocker therapy.[2]
• Surgical left cardiac sympathetic denervation in selected patients whose symptoms and/or ventricular arrhythmias are not controlled by pharmacologic therapy [3][4]
• Avoid competitive and other strenuous exercise

References

3. Wilde AA, Bhuiyan ZA, Crotti L, Facchini M, De Ferrari GM, Paul T, Ferrandi C, Koolbergen DR, Odero A, and Schwartz PJ. Left cardiac sympathetic denervation for catecholaminergic polymorphic ventricular tachycardia. N Engl J Med. 2008 May 8;358(19):2024-9. DOI:10.1056/NEJMoa0708006 |
5. Leenhardt A, Lucet V, Denjoy I, Grau F, Ngoc DD, and Coumel P. Catecholaminergic polymorphic ventricular tachycardia in children. A 7-year follow-up of 21 patients. Circulation. 1995 Mar 1;91(5):1512-9. DOI:10.1161/01.cir.91.5.1512 |

6. pmid-23022705

7. van der Werf C, Kannankeril PJ, Sacher F, Krahn AD, Viskin S, Leenhardt A, Shimizu W, Sumitomo N, Fish FA, Bhuiyan ZA, Willems AR, van der Veen MJ, Watanabe H, Laborderie J, Haïssaguerre M, Knollmann BC, and Wilde AA. Flecainide therapy reduces exercise-induced ventricular arrhythmias in patients with catecholaminergic polymorphic ventricular tachycardia. J Am Coll Cardiol. 2011 May 31;57(22):2244-54. DOI:10.1016/j.jacc.2011.01.026 |
8. van der Werf C and Wilde AA. Catecholaminergic polymorphic ventricular tachycardia: important messages from case reports. Europace. 2011 Jan;13(1):11-3. DOI:10.1093/europace/euq330 |
9. Priori SG, Napolitano C, Memmi M, Colombi B, Drago F, Gasparini M, DeSimone L, Coltorti F, Bloise R, Keegan R, Cruz Filho FE, Vignati G, Benatar A, and DeLogu A. Clinical and molecular characterization of patients with catecholaminergic polymorphic ventricular tachycardia. Circulation. 2002 Jul 2;106(1):69-74. DOI:10.1161/01.cir.0000020013.73106.d8 |
10. van der Werf C, Nederend I, Hofman N, van Geloven N, Ebink C, Frohn-Mulder IM, Alings AM, Bosker HA, Bracke FA, van den Heuvel F, Waalewijn RA, Bikker H, van Tintelen JP, Bhuiyan ZA, van den Berg MP, and Wilde AA. Familial evaluation in catecholaminergic polymorphic ventricular tachycardia: disease penetrance and expression in cardiac ryanodine receptor mutation-carrying relatives. Circ Arrhythm Electrophysiol. 2012 Aug 1;5(4):748-56. DOI:10.1161/CIRCEP.112.970517 |