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The clinical manifestations of CPVT usually occur in the first decade of life prompted by physical activity or emotional stress.1045 Most CPVT patients have normal ECG and echocardiogram. Nonetheless, some patients present mild ECG abnormalities, such as sinus bradycardia and prominent U waves. Exercise stress test is the most important diagnostic test, because it elicits the distinguishing bidirectional or PVT that establish the diagnosis (Figure 36).135 A diagnosis can also be made in the presence of a mutation in genes associated with CPVT. Epinephrine or isoproterenol challenge may be considered when exercise stress testing is not feasible.1046 Diagnosis in childhood, the lack of beta-blocker therapy, and complex arrhythmias during the exercise stress test on a full dose of betablockers are independent predictors for arrhythmic events.1047 Exercise restriction and beta-blockers without intrinsic sympathomimetic activity are the first-line therapy for CPVT patients.135 Non-selective beta-blockers such as nadolol and propranolol are preferred.1048,1049 This panel has confirmed the indication to treat genetically positive family members with beta-blockers, even in the absence of documented exercise- or stress-induced VAs.1047,1050 Data suggest that flecainide significantly reduces the VA burden in CPVT patients and should be considered in addition to beta-blockers when control of arrhythmias is incomplete.1051–1053 In selected patients who show intolerance to beta-blocker therapy, pharmacological therapy with flecainide alone is an option.1054 Maximal protection with beta-blockers, flecainide and ICD is indicated in survivors of a CA. An ICD should also be considered in CPVT patients with breakthrough VA on beta-blockers and flecainide.135 The ICD should, however, be programmed with long delays and high rates before defibrillation, because initiating bidirectional VT responds less effectively to defibrillation than subsequent PVT/VF, and painful shocks can trigger further and incessant arrhythmias.1055 LCSD has been proposed as an additional therapy in patients in whom pharmacological treatment is not effective or feasible. Although LCSD reduces the recurrence of major cardiac events in previously symptomatic patients, one-third of patients still suffer recurrences of arrhythmia.1056 Therefore, LCSD has not been considered to be a replacement for ICD therapy but a complementary therapy in symptomatic patients. A recent systematic review of 53 studies including CPVT patients with an ICD concluded that secondary prevention patients managed with OMT, LCSD and exercise restriction could reduce ICD use.1057 This observation was supported by a subsequent multicentric investigation showing that all the three SCD observed occurred in patients with an ICD.1058 At present it seems premature, on the base of this evidence, to demote ICD implant in survivors of CA with CPVT.1057 Patient with CPVT ICD implantation (Class I) Flecainide (Class IIa) LCSD (Class IIa) Flecainide (Class IIa) General r ecommendations a (Class I) Beta-bloc k er k k b (Class I) Beta-bloc k er k k b (Class IIa) A r r h ythmic syncope or bidi r ectional or po l ymorphic VT Abo r ted ca r diac a r r est Syncope or e x e r tional PVCs or V T Syncope or e x e r tional PVCs or VT Syncope or documented V T Syncope or documented VT ICD implantation (Class IIa) LCSD (Class IIa) Asymptomati c , no documented , V A V V , but pathogenic , m utation Figure 35 Management of patients with catecholaminergic polymorphic ventricular tachycardia. CPVT, catecholaminergic polymorphic ventricular tachycardia; ICD, implantable cardioverter defibrillator; LCSD, left cardiac sympathetic denervation; PVC, premature ventricular complex; VA, ventricular arrhythmia; VT, ventricular tachycardia. aGeneral recommendations: avoidance of competitive sports, avoidance of strenuous exercise, avoidance of stressful environments. bPreferred beta-blockers: nadolol, propranolol. Downloaded from academic.oup.com/eurheartj/article/43/40/3997/6675633 by guest on 07 October 2026