Background Adult congenital heart disease (ACHD) is a highly underrepresented entity in medical literature, especially in the middle‐eastern region. Hypothesis This study is the first to assess the prevalence of adult congenital heart disease among the population of Kuwait. Methods After a retrospective register review of patients in Kuwait being followed up in the chest diseases hospital was conducted, patients who fit the inclusion criteria were enrolled in the study. Using the American College of Cardiology Task Force 1 of the 32nd Bethesda conference classification of the severity of ACHD, the patients were classified into those with simple, moderate, and complex congenital heart diseases. The age and gender of the patients, as well as the type repair performed, and the residual cardiac findings were recorded to assess the association between the complexity and residuals. Associations were assessed using STATA 15. Results A total of 611 patients were evaluated over a period of 18 months. The youngest participant was 20 years of age, and the oldest participant was 88 years old. Male participants with moderate congenital heart disease class were more common in our study population. Patients with complex congenital heart disease have more residual cardiac lesion than the moderate or simple groups. Almost (70%) of patients with complex cardiac anomalies have undergone either partial or complete repair. The most prevalent cardiac defect was atrial septal defect (21.5%). Tetralogy of Fallot was the most prevalent defect in the moderate group, representing (13%) of the group. The most prevalent anomaly in the complex group was double outlet right ventricle (DORV) representing (15.38%). Conclusion Adult Congenital heart disease is a growing entity of heart disease due to advanced repair techniques. This population requires registries to document cases and assign specialists for the management and care of this special group of patients. Highlights First database of adult congenital heart disease in Kuwait. The most prevalent heart defect was ASD in Kuwait. TOF was the most prevalent defect in the moderate group; and DORV was the most prevalent in the complex group. Patients with moderate ACHD tended to have a more complete repair than those in the complex group.

Logistic regression was used to describe adjusted risk of mortality of older versus younger patients (adjusted for any history of heart failure, hypercholesterolemia, peripheral vascular disease, chronic obstructive pulmonary disease, ischaemic heart disease, presence of STEMI on presenting ECG, female sex, cardiogenic shock at presentation). Results 11,763 patients were diagnosed with ACS. 39% of patients were older (≥75 years); [Table 1]. Male 61%, female 39% in the older group and male 76%, female 24% in the younger group. Older patients had a greater comorbidity burden than younger patients [Table 1]. Percutaneous coronary intervention was performed in less older patients than younger patients (81.2% versus 86.2%, p<0.001). At discharge, older patients were prescribed less secondary-prevention medications than younger patients [Figure 1]. Median follow up was 4.8 years.Older patients were more likely to be readmitted to hospital with heart failure/recurrent MI post discharge than younger patients (22.7% versus 17.3%, p<0.001), but there was no difference in median readmission time (older 1.16 years; younger 1.33 years, p=0.33). When adjusted for baseline demographics and comorbidity, older patients had a greater risk of in-hospital mortality than younger patients (adjusted odds ratio (OR) 2.01, 95% confidence interval (CI) 1.54-2.61, p<0.001) [Table 2]. Older male patients had a greater risk of in-hospital death than younger males (adjusted OR 2.55, 95% CI 1.80-3.60, p<0.001). There was no difference in the risk of mortality for older patients compared with younger patients at one-year (adjusted hazard ratio (HR) 0.95, 95% CI 0.82-1.09, p=0.46) and at long-term follow up (HR 0.98, 95% CI 0.87-1.10, p=0.68). Conclusions Overall 39% of ACS patients were ≥75 years. This group of patients are more likely to die in-hospital and be readmitted following discharge, than younger patients. Older patients have a greater comorbidity burden than younger patients yet are discharged with less secondary prevention.