Introduction: Spontaneous type 1 Brugada ECG in standard leads (4 th intercostals space) is a known risk factor for cardiac events. Expert consensus recommendations suggested diagnosis of Brugada syndrome (BS) with type 1 pattern in the precordial leads, positioned in the 2nd, 3rd intercostals space (high leads). Whether spontaneous type 1 in a high location carries the same prognostic value as in the standard leads is uncertain. The objective was to examine the role of high leads in ECG or 12 channel holter ECG recording in the risk stratification of BS.
Methods: Consecutive 216 patients (age 37± 17, 73% males) with clinical diagnosis of BS and positive genetic analysis were included. ECG and 12 channel holter ECG were analyzed for a type 1 pattern in either the standard or high leads. The risk for total and severe cardiac events was assessed during the follow up.
Results: Thirty patients had type 1 pattern in high leads only, 79 had type 1 pattern in standard leads and 107 patients did not have a spontaneous type 1 pattern. During the follow up of 6.6± 2.9 years, 37 patients (17%) had events. Fifteen patients (7%) had severe events (3 sustained VT and 12 cardiac arrest). In Cox regression analysis type 1 pattern in high leads only was a risk factor for total events (95%CI 1.05-5.7, HR 2.5, p= 0.037), for severe events (95%CI 1.5-23.5, HR 6, p= 0.009) and a risk factor for cardiac arrest (95%CI 1.1-28.1, HR 5.6, p= 0.034). In Kaplan Meier curves Brugada patients with type 1 pattern in high leads only had the same long term prognosis regarding total events, severe events and cardiac arrest as patients with type 1 pattern in the standard leads.
Conclusion: Spontaneous type 1 pattern in high leads as in the standard leads is a risk factor for total events, severe cardiac events and cardiac arrest in BS.
