Clinical Characteristics, Diagnosis, and Impact on Employment in Patients With Obstructive Hypertrophic Cardiomyopathy: Results From a Real-World Survey in Canada

OBJECTIVES: To describe the clinical characteristics, diagnosis and employment status of patients with obstructive hypertrophic cardiomyopathy (oHCM) in Canada.

METHODS: Cardiologists provided information on up to 6 consecutive adult patients with symptomatic oHCM based on their medical records between December 2022 and April 2023, as part of the Adelphi HCM Disease Specific Programme, a cross-sectional survey with retrospective data collection. Analyses were descriptive.

RESULTS: 41 cardiologists provided data for 151 patients with oHCM, of which 82.8% were currently NYHA II, 15.9% NYHA III and 1.3% NYHA IV. The mean [standard deviation, SD] age was 55.5 [15.35] years and 68.2% were male. The mean [SD] time since diagnosis was 2.2 [2.7] years for NYHA II, and 3.1 [4.2] years for NYHA III patients. A fifth of patients (20.4%) experienced a delayed diagnosis, of these 61.1% were diagnosed at NYHA II, 33.3% at NYHA III, and 5.6% at NYHA IV. Almost a quarter of patients (23.8%) were not receiving treatment for oHCM, of which 14.6% had never received treatment. The most frequent reasons for not receiving treatment were due to the patient being mildly symptomatic (61.1%) or refusing treatment (22.2%). 11.3% of patients had undergone septal reduction therapy and 76.2% were currently receiving pharmacological treatment for oHCM. Of these, 81.4% were receiving beta-blockers and 16.3% were receiving calcium-channel blockers, alone or in combination with other treatments. No mavacamten treatment use was reported. The most prevalent symptoms experienced by patients receiving treatment were dyspnoea when active (93.9%), fatigue (27.0%) and palpitations (24.3%). Of patients receiving treatment, 34.8% were not in full-time employment, of which 7.5% were not working due to HCM.

CONCLUSIONS: Obstructive HCM is associated with substantial clinical impacts. Despite current treatment, considerable symptom burden remains, affecting some patients’ ability to remain in work, and highlighting the need for new treatment options.