An evidence review and gap analysis for obstructive hypertrophic cardiomyopathy.

BACKGROUND: Patients with obstructive hypertrophic cardiomyopathy (oHCM) have a substantial humanistic, clinical, and economic burden due to the array of symptoms and complications associated with the disease. The objective of this review was to identify key evidence gaps related to oHCM, specifically in Europe, North America, and Japan. METHODS: A targeted literature review was conducted using PubMed to identify English-language studies published between 2012 and 2022 assessing patients with HCM/oHCM in France, Germany, Italy, Spain, the United Kingdom (UK), the United States (US), Canada, and Japan. Outcomes of interest were epidemiology, natural history, pathophysiology, management, and clinical, economic, and humanistic burden. Identified studies were assessed qualitatively to characterize evidence gaps. RESULTS: Among 2,262 abstracts and 531 full-text articles screened, 178 articles were included from PubMed searches. An additional 16 unique studies were identified via a supplemental Google Scholar search initially conducted in January 2023 and updated in July 2024. Disease natural history, pathophysiology, and management were well documented globally. Significant evidence gaps were noted for the epidemiology, treatment, and burden of oHCM. Although multiple US studies were identified on the clinical, economic, and humanistic burden of oHCM, and one clinical burden study was found for Japan, there was a lack of evidence for France, Germany, Italy, Spain, the UK, and Canada. CONCLUSIONS: Major evidentiary gaps exist for the epidemiology, treatment, and burden of oHCM. Future research should address these gaps, with a specific focus on generating real-world evidence for Canada and European countries that will support the evaluation of emerging therapies in these regions.

The prognostic value of peak oxygen uptake in obstructive hypertrophic cardiomyopathy: a literature review to inform economic model development.

AIMS: Patients with obstructive hypertrophic cardiomyopathy (oHCM) experience significant clinical burden which is associated with a high economic burden. Peak oxygen uptake (pVO2), measured by cardiopulmonary exercise testing, is used to quantify functional capacity, and has been studied as a primary endpoint in recent clinical trials. This study aimed to gather evidence to consolidate the prognostic value of pVO2 in oHCM and to assess whether it is feasible to predict health outcomes in an economic model based on changes in pVO2. METHODS: A targeted literature review was conducted in MEDLINE (via PubMed) and Embase databases to identify evidence on the prognostic value of pVO2 as a surrogate health outcome to support future oHCM economic model development. Following screening, study characteristics, population characteristics, and pVO2 prognostic association data were extracted. RESULTS: A total of 4,687 studies were identified. In total, 3,531 and 538 studies underwent title/abstract and full-text screening, respectively, of which 151 were included and nine of these were in hypertrophic cardiomyopathy (HCM); only three studies focused on oHCM. The nine HCM studies consisted of one systematic literature review and eight primary studies reporting on 27 potentially predictive relationships from a pVO2-based metric with clinical outcomes including all-cause mortality, cardiovascular mortality, sudden cardiac death, transplant, paroxysmal, and permanent atrial fibrillation. pVO2 was described as a predictor of single and composite endpoints, in three and six studies, respectively, with one study reporting on both. LIMITATIONS: This study primarily uses systemic literature review methods but does not qualify as one due to not entailing parallel reviewers during title-abstract and full-text stages of review. CONCLUSION: The findings of this study suggest pVO2 is predictive of multiple health outcomes, providing a rationale to use pVO2 in the development of an economic model.

Obstructive hypertrophy cardiomyopathy (oHCM) is a condition where the heart muscle thickens, obstructing blood flow and potentially impacting health. Peak oxygen uptake (pVO2) measures the highest amount of oxygen consumption during peak exercise and serves as an indicator of fitness. pVO2 can be used to assess heart health and predict severe conditions and death, acting as a surrogate endpoint. Surrogate endpoints are valuable in drug investigations since they allow earlier decisions on drug approval and funding before longer-term patient follow-up is available.This study reviewed evidence on the relationship between pVO2 values in patients with heart disease and the risk of becoming sicker or dying. Our goal was to assess if these relationships had been established and whether it is feasible to use them to predict future treatment benefits and support economic evaluations of new treatments. Our review found that most studies reported on patients with heart failure, with only nine focusing on HCM. Evidence indicates that low pVO2 values in patients with heart disease are linked to an increased risk of developing other heart conditions, needing a heart transplant, or dying.

Healthcare resource utilization and cost of obstructive hypertrophic cardiomyopathy in a US population.

Background: There are limited data evaluating all-cause and disease-related healthcare resource utilization (HCRU) and cost of care for patients with obstructive hypertrophic cardiomyopathy (oHCM). Methods: This was a retrospective study using US longitudinal medical and pharmacy claims data during 2012-2020. Adults with ≥2 oHCM diagnoses were identified, with the first diagnosis date used as the index date. HCRU and costs of care were reported for the year preindex (baseline) and at 1- and 2-year follow-ups. Results: We identified 1841 patients with oHCM (63 ± 15 years; 52% male). The mean number of hypertrophic cardiomyopathy (HCM)-related outpatient and cardiology visits increased from baseline to 1-year follow-up (2.3 vs. 7.8 and 0.6 vs. 2.2, respectively). At baseline, 8% of patients had ≥1 HCM-related inpatient hospitalization (mean 0.11 visits, 5.4 days length of stay), increasing to 27% postdiagnosis (mean 0.42 visits, 5.9 days length of stay). Total HCM-related costs increased from $5968 to $20,290 at 1-year follow-up, largely driven by inpatient hospitalization costs ($3889 vs. $14,369) and surgical costs ($2259 vs. $7217). The proportion with ≥1 HCM-related prescription increased from baseline (69%; mean fills 5.3) to 1-year follow-up (82%; mean fills 7.8). Pharmacy costs were generally low but also increased ($449 vs. $752). Conclusions: This benchmark economic dataset for management and evaluation of patients with oHCM shows increased HCM-related costs over a 2-year period after oHCM diagnosis, driven by inpatient hospitalizations and surgical costs. Medication use was high, but costs were low, possibly reflecting use of generic multi-indication drugs for oHCM treatment.