title: A novel approach in the use of radiofrequency catheter ablation of septal hypertrophy in hypertrophic obstructive cardiomyopathy.
abstract: OBJECTIVE
  Alcohol septal ablation (ASA) is a therapeutic alternative to surgical myectomy in patients with hypertrophic obstructive cardiomyopathy (HOCM). However, the anatomical variability of the septal branch, risk of complete heart block, and late onset ventricular arrhythmias are limitations to its therapeutic usage. There is recent interest in the use of radiofrequency catheter ablation (RFCA) as a therapeutic option in HOCM. We aimed to assess the safety and efficacy of RFCA in the treatment of symptomatic HOCM.
  
  
  METHODS
  Seven patients with symptomatic HOCM (mean age 43.7±15.6 years, five males), and significant left ventricular outflow tract (LVOT) gradient despite optimal drug therapy, underwent ablation of the hypertrophied interventricular septum. These patients had unfavorable anatomy for ASA. Ablation was performed under 3D electro-anatomical system guidance using an open irrigated tip catheter. The region of maximal LV septal bulge as seen on intracardiac echocardiography was targeted. Patients were followed up at 1, 6, and 12 months post-procedure.
  
  
  RESULTS
  The mean baseline LVOT gradient by Doppler echocardiography was 81±14.8mm of Hg which reduced to 48.5±22.6 (p=0.0004), 49.8±19.3 (p=0.0004), and 42.8±26.1mm of Hg (p=0.05) at 1, 6, and 12 months respectively. Symptoms improved at least by one NYHA class in all but one patient. One patient developed transient pulmonary edema post-RFA. There were no other complications.
  
  
  CONCLUSIONS
  RFCA of the hypertrophied septum causes sustained reduction in the LVOT gradient and symptomatic improvement among patients with HOCM. Electroanatomical mapping helps to perform the procedure safely.
authors: Department of Cardiac Electrophysiology, CARE Hospitals, Hyderabad, India.
authors: Abhijeet B
authors: AB
authors: Shelke
authors: Department of Cardiology, CARE Hospitals, Hyderabad, India.
authors: Rajeev
authors: R
authors: Menon
authors: Department of Cardiology, CARE Hospitals, Hyderabad, India.
authors: Anuj
authors: A
authors: Kapadiya
authors: Department of Cardiac Electrophysiology, CARE Hospitals, Hyderabad, India.
authors: Sachin
authors: S
authors: Yalagudri
authors: Department of Cardiac Electrophysiology, CARE Hospitals, Hyderabad, India.
authors: Daljeet
authors: D
authors: Saggu
authors: Department of Cardiac Electrophysiology, CARE Hospitals, Hyderabad, India.
authors: Sandeep
authors: S
authors: Nair
authors: Department of Cardiac Electrophysiology, CARE Hospitals, Hyderabad, India. Electronic address: calambur1@gmail.com.
authors: C
authors: C
authors: Narasimhan
mesh_terms: D000328:Adult; D002312:Cardiomyopathy, Hypertrophic / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D017115:Catheter Ablation / Q000379:methods*; D015150:Echocardiography, Doppler; D005260:Female; D005500:Follow-Up Studies; D006346:Heart Septum / Q000000981:diagnostic imaging / Q000601:surgery*; D006352:Heart Ventricles / Q000000981:diagnostic imaging* / Q000503:physiopathology; D006801:Humans; D006984:Hypertrophy / Q000175:diagnosis / Q000601:surgery; D021621:Imaging, Three-Dimensional; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D025321:Surgery, Computer-Assisted / Q000379:methods*; D016896:Treatment Outcome; D016277:Ventricular Function, Left / Q000502:physiology*; D055815:Young Adult
keywords: Alcohol septal ablation; Hypertrophic obstructive cardiomyopathy; Left ventricular outflow tract; Radiofrequency ablation