Anesthetic management during endocardial radiofrequency ablation of septal hypertrophy – a case report

Background: Hypertrophic cardiomyopathy (HCM) is a genetic disorder present in up to 1/500 individuals, about 20–30% of them presenting with hypertrophic obstructive cardiomyopathy (HOCM) due to left ventricle outflow tract obstruction. This is an important cause of sudden cardiac death. Endocardial radiofrequency ablation of septal hypertrophy (ERASH) might be an attractive treatment for HOCM, particularly in patients who do not respond to transcoronary alcohol septal ablation (TASA). Aim: To describe technical aspects related to the procedure and anesthetic management of an ERASH case. Case report: A 64-year-old woman with HOCM was scheduled for ERASH. She had worsening of dyspnea on exertion and generalized fatigue for the previous weeks after previous surgical myomectomy about 6 months ago. The anatomy was unfavorable for TASA and the patient was not willing to undergo another surgery. Preoperative transthoracic echocardiography (TTE) showed asymmetric mid-septal hypertrophy, systolic anterior motion with septal contact and left ventricular outflow tract maximum gradient of 68 mmHg at rest and 105 mmHg after the Valsalva maneuver. General anesthesia was performed. Pulse pressure variation, echocardiography parameters and passive leg raising test where used to guide fluid therapy. At the end of the procedure, analgesia was provided together with prophylaxis of nausea and vomiting. Extubation was uneventful and the patient was transported to the intensive care unit eupneic and hemodynamically stable. On the fourth postoperative day, TTE showed septal hypocontractility and maximum gradient reduction of 33% at rest (68 mmHg to 45 mmHg) and 31% after the Valsalva maneuver (105 mmHg to 73 mmHg). The patient was discharged from hospital at the sixth postoperative day. One month later, she reported progressive improvement of symptoms and expressed satisfaction with the results. Conclusion: Better understanding of the pathophysiology and natural history of HCM has enabled earlier diagnosis, as well as a more adequate therapeutic approach. Anesthesiologists should be aware of the pathophysiology of HOCM and must be prepared to anticipate the hemodynamic changes and cardiovascular instability that such patients may show perioperatively. ERASH is a promising therapeutic modality increasingly used for HOCM and anesthesiologists should become more familiar with it.