Article Text
Abstract
Background and Aims Hypertrophic Cardiomyopathy (HCM) is characterized by marked hypertrophy of the myocardium and it’s frequently accompanied by dynamic left ventricular outflow tract (LVOT) obstruction. Although patients with HCM may not demonstrate LVOT obstruction under basal conditions, dynamic obstruction can develop with the administration of anesthesia. Classically, LVOT obstruction has been considered a relative contraindication to neuraxial anesthesia.
Methods We report a case of a successful continuous subarachnoid block (CSB) in a 66-year-old, ASA III, female patient with HCM proposed for urgent right ankle fracture surgery. Pre-operative transthoracic echocardiogram showed asymmetrical left ventricular hypertrophy and a peak LVOT gradient of 13mmHg at rest and 67mmHg with Valsalva maneuvre. After informed consent and placement of invasive arterial pressure monitoring, premedication with 1mg of midazolam was conducted.An ultrasound-guided popliteal sciatic nerve block with 20mL of 0,375% ropivacaine was performed on the right leg followed by placement of a subarachnoid catheter at the L3-L4 level. A total of 2,5mg of 0,5% levobupivacaine and 0,003mg of sufentanyl were injected into the subarachnoid space.The surgery was uneventful and the patient remained hemodynamically stable. No complications were reported and the patient was later discharged home.
Results In our case the execution of a CSB allowed for titration of local anesthetic dosage, which permitted hemodynamic stability while giving optimal anesthetic effect. We also believe the use of premedication as well as peripheral nerve blockade for perioperative analgesia contributed to the overall success of this case.
Conclusions Anesthesiologists must understand the physiopathology of this disease, as LVOT obstruction can cause life-threatening hemodynamic instability.