Study On The Efficacy And Influencing Factors Of Liwen Procedure In The Treatment Of Mild Hypertrophic Obstructive Hypertrophic Cardiomyopath

Part I Clinical effect of the Liwen procedure in the treatment of HOCM patients with mild septal hypertrophyObjective: To evaluate the clinical efficacy of percutaneous intramyocardial septal radiofrequency ablation(Liwen procedure)in the treatment of obstructive hypertrophic cardiomyopathy(HOCM)with mild septal hypertrophy.Methods: Eighty HOCM patients with mild septal hypertrophy(the maximal left ventricular wall thickness is 15mm~19mm)who were treated with Liwen procedure between November 2016 to July 2021 in the Hypertrophic Cardiomyopathy Center of Xijing Hospital of Air Force Military Medical University were enrolled,collected and analyzed their clinical data.The clinical symptoms and NYHA functional class before operation and last follow-up were collected.Interventricular septum thickness,left ventricular outflow tract pressure gradient,left ventricular outflow tract diameter,mitral regurgitation,left ventricular systolic and diastolic function were evaluated by transthoracic echocardiography before operation and last follow-up,intraoperative complications were monitored and recorded.Postoperative arrhythmias were monitored by routine 12 lead ECG and 24-hour ambulatory ECG.Results: All patients successfully completed Liwen procedure.No clinical adverse events such as death,bleeding and stroke occurred during and around the operation.No left bundle branch block,complete atrioventricular block and malignant arrhythmia occurred after the operation.All patients did not need permanent pacemaker implantation.NYHA functional class and clinical symptoms of patients were significantly improved at last follow-up compared with values before operation(all P < 0.001,respectively);Anterior interventricular septum,posterior interventricular septum,maximal left ventricular wall thickness all significantly decreased(all P<0.001,respectively),left ventricular outflow tract diameter widened(P<0.001);left ventricular outflow tract gradient and provoked left ventricular outflow tract gradient all significantly decreased,mitral regurgitation decrease and SAM classification reduced at last follow-up compared with values before operation(all P<0.001,respectively);left ventricular end-diastolic diameter widened and left atrial diameter decreased(all P<0.001,respectively).Left atrial volume index decreased(P<0.001)and the ratio of early diastolic mitral valve velocity to early diastolic mitral annulus velocity(E/e’)decreased(P < 0.001).There was no significant difference in left ventricular end diastolic volume,left ventricular end systolic volume and left ventricular ejection fraction among the three groups(all P>0.05).Conclusion: Liwen procedure is effective in the treatment of obstructive hypertrophic cardiomyopathy with mild septal hypertrophy.Part Ⅱ Analysis of influence factors for the efficacy of Liwen procedure in the treatment of HOCM patients with mild septal hypertrophyObjective: To explore the influence factors of postoperative efficacy of percutaneous intramyocardial septal radiofrequency ablation(Liwen procedure)in the treatment of HOCM patients with mild septal hypertrophy.Methods: A total of 80 HOCM patients with mild septal hypertrophy(the maximal left ventricular wall thickness is 15mm~19mm)treated in the Hypertrophic Cardiomyopathy Center of Xijing Hospital of Air Force Military Medical University from October 2016 to July 2021 were retrospectively analyzed.All patients had been treated with Liwen procedure,and they were divided into the effective group and the ineffective group according to the postoperative efficacy.The clinical data,ablation parameters,conventional echocardiographic parameters and mitral valve parameters of two groups were collected,and univariate and multivariate logistic regression analysis was performed to determine the influencing factors of the efficacy of Liwen procedure in the treatment of HOCM patients with mild septal hypertrophy.Result: Univariate analysis showed that SAM-Ao,C-sept and sigmoid septum were statistically significant between the two groups(all P < 0.05).Multivariate logistic regression analysis showed that SAM-Ao and sigmoid septum were independent factors influencing postoperative efficacy after Liwen procedure treatment of HOCM patients with mild septal hypertrophy(all P<0.05).Conclusion: SAM-Ao and sigmoid septum were independent factors affecting postoperative efficacy in HOCM patients with mild septal hypertrophy after Liwen procedure,and it is necessary to take positive and effective measures according to the influencing factors to improve the effective rate of Liwen procedure in treating such patients.