Prevalence and prognostic relevance of electrocardiographic abnormalities among patients with ANCA-associated vasculitis

Objectives: Current guidelines provide limited evidence for cardiovascular screening in ANCA-associated vasculitis (AAV). This study aimed to investigate the prevalence of ECG abnormalities and associations between no, minor or major ECG abnormalities with cardiovascular mortality in AAV patients compared with matched controls. Methods: Using a risk-set matched cohort design, patients diagnosed with granulomatosis with polyangiitis or microscopic polyangiitis with digital ECGs were identified from Danish registers from 2000 to 2021. Patients were matched 1:3 to controls without AAV on age, sex and year of ECG measurement. Associated hazards of cardiovascular mortality according to ECG abnormalities were assessed in Cox regression models adjusted for age, sex and comorbidities, with subsequent computation of 5-year risk of cardiovascular mortality standardized to the age- and sex-distribution of the sample. Results: A total of 1431 AAV patients were included (median age: 69 years, 52.3% male). Median follow-up was 4.8 years. AAV was associated with a higher prevalence of left ventricular hypertrophy (17.5% vs 12.5%), ST-T deviations (10.1% vs 7.1%), atrial fibrillation (9.6% vs 7.5%) and QTc prolongation (5.9% vs 3.6%). Only AAV patients with major ECG abnormalities demonstrated a significantly elevated risk of cardiovascular mortality [HR 1.99 (1.49-2.65)] compared with controls. This corresponded to a 5-year risk of cardiovascular mortality of 19.14% (16-22%) vs 9.41% (8-11%). Conclusion: Patients with AAV demonstrated a higher prevalence of major ECG abnormalities than controls. Notably, major ECG abnormalities were associated with a significantly increased risk of cardiovascular mortality. These results advocate for the inclusion of ECG assessment into routine clinical care for AAV patients.