Study population
The present study retrospectively evaluated 169 consecutive patients (age 70±12, 87 males, 98 paroxysmal AF) with HCM and AF who were followed up at Nippon Medical School hospital from January 2009 to December 2020. The diagnosis of HCM was based on two-dimensional echocardiographic evidence of a hypertrophied, non-dilated left ventricle (maximum wall thickness ≥15 mm) in the absence of systemic or cardiac disease capable of making the magnitude of the hypertrophy evident. Among the 169 patients with HCM and AF, 63 underwent CA of drug-refractory AF (ablation group) and the remaining 106 did not (control group). The patients in both groups were followed up every one to three months with optimal medical therapy including oral anticoagulants during the study period. Patients with chronic hemodialysis, a previous history of catheter ablation, and percutaneous coronary intervention within six months before starting the observation were excluded.
Propensity score matching was used to match the patient’s clinical characteristics between the ablation group and control group12,13. The propensity score was generated from a multivariate logistic regression model using four variables associated with changes in the estimated glomerular filtration rate (eGFR): age, gender, body mass index (BMI), and baseline eGFR. After the propensity score generation, the ablation group and control group underwent 1:1 nearest neighbor matching of the logit of the propensity score with a caliper width of 0.25. The patients who did not meet the matching criteria were excluded. All patients gave their written informed consent for the ablation procedure and they were enrolled in the study notified of the opportunity to opt out. This study protocol was approved by the institutional review board of our institution.