Registries have become pivotal in medical research, offering a robust foundation for understanding disease incidence, treatment patterns, and patient outcomes across diverse populations. By aggregating real-world data (RWD), registries provide invaluable insights into real-world evidence (RWE), shaping clinical guidelines, healthcare policies, and regulatory decisions. Their widespread acceptance underscores their scientific validity and their role in driving evidence-based medicine, ultimately improving healthcare outcomes. In cardiology, particularly within the specialized field of congenital heart disease (CHD), national and international registries have emerged as indispensable tools. They enable the systematic collection of data on patient demographics, disease progression, therapeutic interventions, and long-term outcomes. These datasets support a range of purposes, including observational studies, quality improvement initiatives, and regulatory assessments of medical devices or pharmaceuticals. Establishing a high-quality registry requires meticulous planning and adherence to established guidelines. Professional organizations, such as the European Society of Cardiology (ESC) and the American Heart Association (AHA), offer detailed guidance documents for setting up and managing registries. Additionally, various checklists and frameworks exist to evaluate and ensure registry quality, aiding researchers in optimizing data reliability and utility. With advancements in digital health, the potential of electronic health records (EHRs) to complement or replace traditional registries is increasingly explored. EHRs offer a dynamic, real-time data collection mechanism, reducing redundancy and operational costs while maintaining data accuracy. However, considerations around interoperability, data privacy, and standardization remain critical in leveraging EHRs for registry purposes.

Background: The PATHFINDER-CHD Registry is a prospective, multicenter, non-interventional registry across tertiary care centers in Germany. The aim is to analyze real-world data on adults with congenital heart defects (ACHD) or hereditary connective tissue disorders who have manifest heart failure (HF), a history of HF, or are at significant risk of developing HF. This analysis investigates the prevalence and clinical impact of overweight and obesity in this unique population. Methods: As of 1st February, 2025, a total of 1490 ACHD had been enrolled. The mean age was 39.4 ± 12.4 years, and 47.9% were female. Patients were categorized according to Perloff’s functional class and the Munich Heart Failure Classification for Congenital Heart Disease (MUC-HF-Class). Results: The most common congenital heart disease (CHD) in this cohort was Tetralogy of Fallot, transposition of the great arteries, and congenital aortic valve disease. Marfan syndrome was the most common hereditary connective tissue disease. Of the patients, 46.1% were classified as overweight (32.8%) or obese (13.3%), while 4.8% were underweight. The highest prevalence of overweight (47.1%) was observed among patients who had undergone palliative surgery, whereas untreated patients showed the highest proportion of normal weight (57.2%). Cyanotic patients were predominantly of normal weight. Patients with univentricular circulation exhibited significantly lower rates of overweight and obesity (35%; p = 0.001). Overweight and obesity were statistically significantly associated with arterial hypertension, diabetes mellitus, and sleep apnea (all p < 0.001). High BMI was linked to increased use of HF-specific medications, including SGLT2 inhibitors (p = 0.040), diuretics (p = 0.014), and angiotensin receptor blockers (p = 0.005). Conclusions: The data highlight the clinical relevance of overweight and obesity in ACHD with HF, emphasizing the need for individualized prevention and treatment strategies. The registry serves as a critical foundation for the optimization of long-term care in this population.

Background: Advances in diagnosis and treatment have led to a growing population of adults with congenital heart disease (ACHD). Despite increasing life expectancy, their clinical needs—especially in older age—remain poorly defined. Cardiac and non-cardiac comorbidities are prevalent, and emerging evidence suggests accelerated biological aging compared to the general population. However, data on older patients and geriatric patients with CHD are limited. Objectives: This study aimed to characterize patients with CHD aged ≥50 years, focusing on functional status, comorbidities, sex-specific differences, and therapeutic patterns. Methods: The PATHFINDER-CHD Registry is a prospective, observational, multicenter registry enrolling patients with CHD with manifest heart failure (HF), HF history, or high HF risk. Data include anatomy, prior treatments, comorbidities, and medication use. Results: Among 1935 patients, 297 were ≥50 years old. Most had acyanotic CHD (62%); Tetralogy of Fallot (21%) was the most frequent diagnosis. A morphologic right systemic ventricle was present in 12%, and 5% had univentricular hearts. HF was manifest in 21%; 44% were classified as ACC/AHA stage B, 51% as stage C, yet 77% were in Perloff class I/II. Common cardiovascular comorbidities included aortopathy (55%), hypertension (37%), and arrhythmia (33%). Non-cardiac comorbidities included thyroid dysfunction (25%), renal impairment (18%), and neurological disease (13%). Sex-specific differences were observed. Despite HF burden, SGLT2 inhibitors and ARNIs were used in only 17% and 8.4%, respectively. Conclusions: Older patients with CHD represent a clinically complex cohort with high comorbidity burden. The findings support the concept of accelerated aging and emphasize the need for tailored interdisciplinary care strategies.

Background/Objectives: Progress in diagnostic and therapeutic strategies has resulted in an increasing prevalence of adults with congenital heart disease (ACHD), including those involving genetically determined syndromes. This study aimed to characterize prevalence, congenital phenotypes, heart failure (HF) stages, comorbidity burden, and current medical management of ACHD and concomitant genetically determined syndromes enrolled in a prospective HF-focused registry. Methods: The PATHFINDER-CHD Registry is a German-based (est. 2022) multicenter observational registry. This web-based platform consecutively tracks ACHD patients across the heart failure spectrum, including those with current or prior HF, as well as those at high structural or functional risk. HF stage was classified using a modified ACC/AHA scheme adapted for CHD; functional capacity was graded according to the Perloff classification. Baseline demographics, CHD anatomy, prior surgical/interventional treatment, cardiac and extracardiac comorbidities, and medication were collected from medical records. Results: Among 1987 enrolled ACHD, 107 (5.4%) had a genetic syndrome (n = 65, 60.7% women; mean age 33.5 ± 9.4 years; range 18–68). Most common syndromes were trisomy 21 (n = 49; 45.8%) and 22q11.2 deletion (n = 27; 25.2%); 31 patients (30.0) had rarer syndromes. Predominant CHD diagnoses were atrioventricular septal defect (n = 42, 39.3%), tetralogy of Fallot (n = 19, 17.8%), and pulmonary atresia with ventricular septal defect (n = 7, 6.5%). A systemic left ventricle was present in 102 (95.3%); 40 (37.4%) had primarily cyanotic CHD, and 7 (6.5%) an Eisenmenger physiology. Most patients (n = 71; 66.4%) had undergone definite surgical repair; 25 patients (23.3%) had at least one catheter intervention, including transcatheter valve implantation in 17 cases (15.9%). HF stage was mainly B (n = 30, 28.0%) or C (n = 75, 70.1%). Perloff functional class I/II was present in 97 (90.7%). Leading cardiac comorbidities included intrinsic aortopathy (n = 49, 45.8%), pulmonary arterial hypertension (n = 12, 11.2%), and arrhythmias (n = 10, 9.3%). Frequent extracardiac comorbidities were thyroid dysfunction (n = 34, 31.8%), kidney disease (n = 16, 15.0%), hyperuricemia (n = 13, 12.1%), and depression (n = 15, 14.0%). Pharmacotherapy was used in 66 patients (61.7%). Beta-blockers (n = 25, 23.4%) were common, while ACEi/ARB (n = 9, 8.4%), diuretics (n = 10, 9.3%), MRAs (n = 8, 7.5%), and SGLT2 inhibitors (n = 3; 2.8%) were infrequently prescribed; no patient received ARNI or digitalis. For targeted treatment of pulmonary arterial hypertension, phosphodiesterase-5 inhibitors (n = 7, 6.5%), endothelin receptor antagonists (n = 6, 5.6%), or prostacyclin analogues (n = 1, 0.9%) were used. As oral anticoagulants, vitamin K antagonists or direct oral anticoagulants (DOACs) were prescribed in 17 cases (15.9%). Forty-one patients (38.3%) received thyroid hormone replacement. Conclusions: Syndromic ACHD constitute a small but clinically high-risk subgroup within an HF-oriented registry, marked by complex CHD, substantial cardio–extracardiac multimorbidity (notably aortopathy, PAH, thyroid disease, renal dysfunction, depression), and low utilization of contemporary HF therapies. These data support specialized, interdisciplinary, longitudinal care pathways and prospective studies addressing outcomes and evidence-based HF management in syndromic ACHD.

Background/Objectives: Heart failure (HF) poses a major challenge in managing adults with congenital heart defects (ACHD). Emerging evidence suggests that HF in ACHD increases the risk of underweight due to heightened metabolic demands, gastrointestinal complications, and psychological factors such as anxiety and depression. Despite its critical implications, few studies have examined this association. This study evaluates the relationship between HF and underweight—defined as a body mass index (BMI) < 18.5—in ACHD. Methods: The Pathfinder-CHD Registry is a prospective, observational, web-based HF registry including ACHD with manifest HF, history of HF, or significant risk for HF. It documents congenital diagnoses, HF type, comorbidities, and treatments. Patients were categorized by BMI into mild (17.00–18.49), moderate (16.00–16.99), and severe (<16.00) underweight. Results: As of September 2024, the registry enrolled 1420 adults (mean age 31.8±11.3 years; 49.2% female). Underweight was present in 59 patients (4.2%): 62.7% mild, 18.6% moderate, and 18.6% severe. Among the remaining 1361 patients, 52.8% had normal weight, 32.8% were overweight, and 14.2% were obese. Women had significantly lower metabolic body weight than men (p = 0.002). Underweight correlated with younger age (p < 0.001) and CHD type (p = 0.02). Notably, 42.9% of underweight patients had cyanotic CHD. Conclusions: Underweight is an underrecognized problem in ACHD with HF. Adults with complex CHD or connective tissue disorders are disproportionately affected. Underweight should be seen as an alarm sign requiring personalized, multidisciplinary management, including nutritional support, tailored therapy, and close monitoring to improve outcomes.