Septal myectomy/myotomy

Septal myectomy/myotomy

Anesthesia type
Airway
Lines and access
Monitors
Primary anesthetic considerations
Preoperative
Intraoperative
Postoperative
Article quality
Editor rating	Unrated
User likes	0

Provide a brief summary here.

Overview

Myotomy and septal myectomy are surgical procedures used primarily to treat hypertrophic obstructive cardiomyopathy (HOCM). This condition is characterized by the thickening of the heart muscle, particularly the interventricular septum, which can obstruct blood flow.

Indications

• Hypertrophic obstructive cardiomyopathy (HOCM)
  • Symptoms: dyspnea, palpitations, arrhythmia, syncope, heart failure, stroke, and sudden death
  • Management of this condition can be medical, electrophysiological or surgical. This article will focus primarily on the open surgical technique
• Symptomatic left ventricular outflow tract (LVOT) obstruction
• Severe mitral regurgitation due to systolic anterior motion (SAM) of the mitral valve
• Refractory symptoms despite medical management (e.g., dyspnea, syncope)

Surgical procedure

• TEE (transesophageal echocardiography) used intraoperatively to guide resection and assess results.

Preoperative management

Patient evaluation

System	Considerations
Airway	Direct vs. indirect laryngoscopy
Neurologic	Paralysis, CPB
Cardiovascular	Biventricular function, valvular abnormalities, integrity of conduction and presence of arrhythmias
Pulmonary
Gastrointestinal
Hematologic	Coagulopathy, may be exacerbated by CPB
Renal
Endocrine
Other

Labs and studies

• Cardiology Assessment: Detailed history and physical examination.
• Imaging: Echocardiogram to assess septal thickness and LVOT gradient. Cardiac MRI may also be used.
• Functional Testing: Stress testing to evaluate symptomatology and obstruction severity.
• Labs
  • CBC
  • CMP
  • Coagulation studies
  • Blood cultures
  • +/- TEG if patient has history of comorbid condition that affects coagulopathy

Patient preparation and premedication

• Continued use of beta-blockers or calcium channel blockers until surgery.
• Consider anxiolytics like midazolam.

Intraoperative management

Monitoring and access

• Standard ASA monitors
• Arterial line
• Central access CVP +/- PA pressures(indicated for RV or LV failure)
• Transesophageal echo(TEE)

Induction and airway management

• General anesthesia with endotracheal intubation.

Positioning

• Supine position for surgical access.
• Shoulder roll
• Arms tucked

Maintenance and surgical considerations

• LV systolic function in patients with HOCM are usually normal to supranormal with a high ejection fraction.
• Diastolic dysfunction in patients with HOCM is caused by decreased ventricular compliance and impaired ventricular relaxation.

• Promote:
  • Increased preload
    • Trendelenburg positioning may be used for episodes of hypotension
  • Adequate afterload

• Avoid:
  • Vasodilators
  • Decreases in SVR
  • Increased inotropy
  • Increased chronotropy
    • Can be treated in perioperative period with B-antagonists(ex. esmolol)
  • Outflow tract obstruction

*Interestingly, halothane has a good profile for patients with HOCM, given it decreases contractility and heart rate.

Postoperative management

Disposition

• Intensive care unit (ICU) monitoring initially.
  • Often intubated
  • Frequently requiring pressors or inotropic agents post-CPB.
• Continuous ECG monitoring for arrhythmias.

Potential complications

• Arrhythmias (atrial fibrillation, ventricular arrhythmias)
• Ventricular septal defect
• Mitral regurgitation
• Bleeding or pericardial effusion
• AV node block requiring pacemaker insertion
• CPB specific complications

Procedure variants

	Variant 1	Variant 2
Unique considerations
Indications
Position
Surgical time
EBL
Postoperative disposition
Pain management
Potential complications