Mortality and survival rate in a scottish cohort of adults with congenital heart disease

Abstract Background Adult patients with congenital heart disease (ACHD) experience higher rates of morbidity and reduced long-term survival in comparison to the general population. The care of this cohort of patients requires specialist expertise which is mainly delivered at tertiary centers. Aims We aim to report the clinical characteristics, mortality rates and causes of death in a contemporary cohort of ACHD patients followed up in a North- East Scottish Health Board. Methods We prospectively followed up ACHD patients aged ≥17 years (n=645) under review at the Regional NHS ACHD Clinic in a North- East Scottish Health Board between the years 2020 and 2023. We recorded the number and the causes of death as documented on our electronic records and on correspondence with primary care physicians. Survival analysis was performed according to the 2020 ESC Guidelines classification of congenital heart disease complexity (Table 4) classes using Kaplan-Meier method with log-rank (Mantel-Cox) test done in IBM SPSS v.24. Results Our ACHD cohort (n=645, 54% females and 46% males) included patients of all three ESC complexity classes (30% mild, 60% moderate and 10% severe). Between 2020 and 2023, 18 patients (2.8%) died, with a total incidence of 0.93 deaths/100 patient years. Median age of death was 59 years (IQR 45–71), and the majority of deceased patients were males (56%). There were 2 deaths in the mild complexity group, 11 deaths in the moderate complexity group and 5 deaths in the severe complexity group (See Table 1). This was found to correspond to an incidence of 0.34, 0.95 and 2.64 deaths/100 patient years respectively. The leading causes of death were heart failure (28%) and malignancy (22%). Using Kaplan-Meier survival analysis we found that the survival distributions for the mild, moderate and severe ACHD complexity groups were statistically significantly different by log-rank test (χ2(2) = 11.47, p < .005) (See Figure 1). Patients with moderate ACHD complexity had a median survival age 67 years (95% CI 58.1-75.9), patients with severe ACHD had median survival age 57 years (95% CI 44.7-69.2). Median survival could not be calculated for the mild group due to lack of data points. Conclusion The ACHD patient group is characterised for a variety of pathophysiology and clinical presentations. They require lifelong medical input and in spite of the local and national expertise, the mortality and morbidity rates are still high. Heart failure was the leading cause of death in this cohort which is similar to previous reported data. Mortality rates were proportional to the complexity of the underlying ACHD diagnosis. The survival rate of patients in the severe complexity group was ten years less than the moderate complex group. ACHD patients in the moderate and severe complexity groups have significantly reduced life expectancy and require access and clinical expertise from National ACHD Specialty Centers.