Analysis of Left Atrial Function after Percutaneous Intramyocardial Septal Radiofrequency Ablation in Hypertrophic Cardiomyopathy

INTRODUCTION: The main goal of our research was to explore the effect of percutaneous intramyocardial septal radiofrequency ablation (PIMSRA) on left atrial (LA) phasic function in hypertrophic cardiomyopathy (HCM). METHODS: The study included 13 patients who underwent PIMSRA at our hospital. The function of LA including reservoir, conduit, and booster pump was analyzed and compared before and 6 months after PIMSRA in HCM patients. LA reservoir function parameters contain maximal LA volume, minimal LA volume (LAV min), LA ejection fraction (LAEF), LA expansion index (LAEI), and reservoir strain; LA conduit function includes LA volume before atrial systole, LA passive volume, LA passive ejection fraction, and conduit strain; LA booster function involves LA booster volume, LA active ejection fraction, and LA contraction strain. Additionally, 20 healthy controls were selected to compare the LA function of HCM patients. RESULTS: The preoperative LA reservoir and conduit function in HCM patients were significantly impaired compared with the control group, while the change in booster pump function was not obvious. HCM patients at 6 months after PIMSRA had remarkably enhanced reservoir and conduit functions which were manifested by lower LAV min, higher LAEF, LAEI, reservoir, and conduit strain than before the operation, and the differences among these parameters between patients after PIMSRA and the healthy control group were not significant. However, with regard to LA contraction function, there was no significant improvement at 6 months after PIMSRA compared with before operation. CONCLUSION: PIMSRA is effective in the amelioration of LA reservoir and conduit function in patients with HCM but not in a marked improvement of LA contraction function in these individuals in short term.