Abstract Body (Do not enter title and authors here): Background
Septal myectomy (SM) and alcohol septal ablation (ASA) are preferred modalities for individuals with symptomatic obstructive hypertrophic cardiomyopathy (HCM). Apart from patient-level factors, operator and hospital volume play a role in determining clinical outcomes in patients undergoing septal reduction therapies. However, contemporary data on the influence of operator and hospital volume on clinical outcomes are lacking.
Methods
This retrospective study used nationwide data from the Vizient^® from 2016-2022. The appropriate ICD-10 diagnosis/procedure codes were used to identify patients with HCM who underwent SM and ASA. Based on operator and hospital volumes, the cohort was stratified into low-, medium-, and high-volume based on tertiles of annualized procedures. The outcomes of interest were 30-day mortality and 90-day readmissions. Multivariable-adjusted logistic and Cox models were used to assess the association of outcomes with operator and hospital volumes.
Results
Among 5,725 HCM patients included in this study, 3,990(69.7%) and 1,735(31.3%) underwent SM and ASA, respectively. Among those who underwent SM, low-(OR_adj:1.86;95%CI:1.11–3.15) and medium-(OR_adj:1.93;95%CI:1.05–3.55) volume operators were associated with higher odds of mortality compared with high-volume operators.(Table) Similarly, medium-volume hospitals had higher odds of mortality post-SM compared with high-volume hospitals (OR_adj:2.29;95%CI:1.32–3.99).(Table) Moreover, low-volume operators (HR_adj:1.51;95%CI:1.22-1.88) and hospitals (HR_adj:1.60;95%CI:1.14-2.23) were associated with greater risk for readmission compared with their high-volume counterparts for SM.(Figure) Among those who underwent ASA, low-(OR_adj:2.99;95%CI:1.15-7.75) and medium-(OR_adj:3.86;95%CI:1.30–11.46) operator volume was associated with higher odds for mortality compared with high-volume operators.(Table) Compared with high-volume operators, the risk of readmission was similar to low-volume operators (HR_adj:1.31;95%CI:0.96-1.77).(Figure) However, hospital volume was not associated with mortality and readmission for ASA.
Conclusions
Low operator and hospital volumes for septal reduction therapies were associated with higher postoperative morbidity and mortality compared with their high-volume counterparts. The current study highlights the need to refer HCM patients requiring septal reduction therapies to high-volume centers with experienced operators who have expertise in performing these procedures.