p.39 抽出テキスト

secondary to pre-excited AF that conducts rapidly to the ventricle over the AP, resulting in ventricular fibrillation, is the most feared manifestation of WPW syndrome. The risk of cardiac arrest/ventricular fibrillation has been estimated at 2.4 per 1000 personyears (95% confidence interval 1.33.9), but no deaths were reported in a registry of 2169 patients over an 8 year follow-up period.439 However, in a Danish registry of 310 individuals with pre-excitation (age range 885 years), there was a greater risk of AF and HF, driven by a right anteroseptal AP, and in patients aged >65 years there was also a statistically significant higher risk of death.22 Clinical and electrophysiological features associated with an increased risk of sudden cardiac death include younger age,439,449,450 inducibility of AV-reciprocating tachycardia during EPS,450454 multiple APs,450,451,455,456 and demonstration of a capability of the AP to allow rapid conduction to the ventricles.439,450,451,453456 These variables include the shortest preexcited RR interval during AF (SPERRI) of <_250 ms at baseline or a short antegrade effective refractory period (ERP) of the AP (<_250 ms).439,450452,454460 With non-invasive testing, identification of an abrupt and complete normalization of the PR interval with loss of delta wave during exercise testing, or following procainamide, propafenone, or dispopyramide administration, has been considered a marker of low risk.459,461463 Catecholamine sensitivity is a major limiting factor of all tests, both invasive452,460 and non-invasive, including exercise testing.459,461,462 Intermittent loss of pre-excitation on a resting ECG or ambulatory monitoring has also been associated with APs with longer ERPs, and has been accepted as a credible risk-stratification tool.2,464 However, a number of recent studies, which have included both symptomatic and asymptomatic patients, have indicated that more than onefifth of patients with intermittent pre-excitation have AP ERPs <250 ms. Thus, intermittent pre-excitation is now recognized as an imperfect marker of a low-risk AP.406,462,465469 Over the past 30 years, a considerable body of literature has been published that has focused on the important topic of the evaluation and management of patients with asymptomatic preexcitation. These publications include those that describe the clinical and electrophysiological characteristics of patients with preexcitation who have experienced a cardiac arrest,439,451,455,459 and series of patients with pre-excitation who are either symptomatic or asymptomatic, and are followed for variable periods of time.22,405,439,449,450,454,456,470472 Among these studies, there has been one prospective RCT of catheter ablation (37 patients) vs. clinical follow-up without treatment (35 patients) of patients with asymptomatic pre-excitation.453 Catheter ablation reduced the frequency of arrhythmic events (7 vs. 77%, P < 0.001) over 5 years. One patient in the control group had an episode of cardioverted ventricular fibrillation. Figure 22 summarizes the recommendations for the screening and management of patients with asymptomatic pre-excitation. Recommendations for the management of patients with asymptomatic pre-excitation

Recommendation Classa Levelb

Performance of an EPS, with the use of isoprenaline, is recommended to risk stratify individuals with asymptomatic pre-excitation who have high-risk occupations/hobbies,c and those who participate in competitive athletics.439,450452,454460 I B Catheter ablation is recommended in asymptomatic patients in whom electrophysiology testing with the use of isoprenaline identifies high-risk properties, such as SPERRI <_250 ms, AP ERP <_250 ms, multiple APs, and an inducible AP-mediated tachycardia.439,450,452,454460 I B Catheter ablation is recommended in high-risk patients with asymptomatic pre-excitation after discussing the risks, especially of heart block associated with ablation of anteroseptal or MS APs, and benefits of the procedure.439,440,473476 I C Performance of an EPS to risk stratify individuals with asymptomatic pre-excitation should be considered.439,450452,454460 IIa B Non-invasive evaluation of the conducting properties of the AP in individuals with asymptomatic pre-excitation may be considered.459,461463,465469 IIb B Invasive risk stratification with an EPS is recommended in patients without ‘low-risk’ characteristics at non-invasive risk stratification.462,463,465469,477 I C Clinical follow-up should be considered in a patient with asymptomatic pre-excitation and a low-risk AP at invasive risk stratification.450,452,456,463,477 IIa C Catheter ablation may be considered in a patient with asymptomatic pre-excitation, and a low-risk AP at invasive or non-invasive risk stratification.405,450,452,456,463,477 IIb C Catheter ablation should be considered in patients with asymptomatic pre-excitation and LV dysfunction due to electrical dyssynchrony.478481 IIa C Catheter ablation may be considered in patients with low-risk asymptomatic pre-excitation in appropriately experienced centres according to patient preferences.203,439,450,453,454,471,474,482 IIb C

AP = accessory pathway; EPS = electrophysiology study; ERP = effective refractory period; LV = left ventricular; MS = mid-septal; SPERRI = shortest pre-excited RR interval during atrial fibrillation. aClass of recommendation. bLevel of evidence cSuch as pilots and professional drivers. Downloaded from academic.oup.com/eurheartj/article/41/5/655/5556821 by guest on 07 October 2026