Assessing the alignment of obstructive hypertrophic cardiomyopathy pharmacological treatments with ESC guidelines in Germany

Abstract Introduction The European Society of Cardiology (ESC) recently updated treatment guidelines for hypertrophic cardiomyopathy (HCM). Purpose The aim of this study was to describe the treatment of obstructive HCM in Germany and assess alignment with the 2014 and 2023 ESC guidelines. Methods Adults with HCM were identified using a nationally representative administrative claims dataset (WIG2 Benchmark database) from several German Statutory Health Insurances between 2012 and 2018. Obstructive HCM was identified as any obstructive HCM diagnosis (ICD-10: I42.1) or any HCM diagnosis (I42.2, I42.9) with septal reduction therapy. The index date was defined as the date where the patient met all eligibility criteria for HCM. Minimum follow-up time was set to one year. Patients had at least 1 year of baseline data prior to the index HCM diagnosis and were followed up for at least 1 year after the diagnosis (or until death within 1 year). Patients with phenocopies were excluded. ESC guideline-directed pharmacological treatments for HCM included beta-blockers (BB), calcium channel blockers (CCB), disopyramide, and/or mavacamten (approved by EMA June 2023). While the 2014 ESC Guidelines on Diagnosis and Management of HCM were applicable during the study, recommendations pertaining to the use of non-vasodilating BBs and non-dihydropyridine (DHP) CCBs did not change in the 2023 ESC Guidelines for the Management of Cardiomyopathies; thus, this study applies to both. Results Out of 6793 patients with HCM analysed in the period 2012-2018, 1,141 had obstructive HCM. The average follow-up was 5 years. Patients were mostly male (62%) with a mean age of 60 years. Hypertension, hyperlipidaemia, coronary artery disease, heart failure, and atrial fibrillation were among the most common comorbidities; the mean Charlson Comorbidity Index score was 2.3. At index, 46% of patients were on BB monotherapy, 23% were on CCB monotherapy, <1% were on a combination of BBs or a combination of CCBs, 9% were on a combination of BBs and CCBs, and as many as 22% received no HCM treatment. Patients experienced 1615 unique treatment combinations throughout the study across all lines of therapy (Table 1). The most common treatments were bisoprolol (24%), metoprolol (19%), amlodipine (12%), and verapamil (12%). The use of propranolol was negligible (1%). 43% of pharmacological treatments were not in line with ESC guidelines. The most common reason for not aligning was using DHP-CCBs or vasodilating BBs. Conclusion This study shows that 57% of obstructive HCM treatments received by patients during the study were aligned with recommendations from the 2023 ESC guidelines on cardiomyopathies. Research is needed to investigate barriers and enablers to implementing the guideline including awareness of recommended treatments, as well as the management of comorbidities.