From the Guidelines
Patients with hypertrophic cardiomyopathy (HOCM) can undergo procedures with sedation, but it is crucial to avoid factors that aggravate or trigger dynamic outflow obstructions, such as positive inotropic agents, tachycardia, or reduced preload, as recommended by the 2024 AHA/ACC/ACS/ASNC/HRS/SCA/SCCT/SCMR/SVM guideline 1. To minimize risks, the anesthesia provider should be informed about the HOCM diagnosis before sedation.
- Medications that increase heart rate or cause significant vasodilation should be avoided or used cautiously.
- Beta-blockers should be continued perioperatively to control heart rate and reduce outflow obstruction, as stated in the 2024 guideline 1.
- Maintaining adequate preload is essential, so patients should be well-hydrated before the procedure.
- During the procedure, the patient should have continuous cardiac monitoring, including blood pressure, heart rate, and oxygen saturation. If hypotension occurs, phenylephrine (50-100 mcg IV boluses) is preferred over ephedrine, as it is less likely to worsen left ventricular outflow tract (LVOT) obstruction 1. The procedure should be performed in a setting where advanced cardiac life support is readily available, due to the increased risk of arrhythmias and hemodynamic instability under sedation in HOCM patients 1.
From the Research
Sedation for Patients with HOCM
- Patients with hypertrophic obstructive cardiomyopathy (HOCM) can undergo procedures under sedation, but careful management is required to maintain adequate preload and afterload, and avoid tachycardia and increased myocardial contractility 2.
- Epidural high dose fentanyl anesthesia has been shown to be a good method for patients with HOCM, as it provides stable blood pressure and heart rate during the operation and recovery period 2.
- Early-extubation anesthesia (EEA) and high-dose opioid (HDO) anesthesia have been compared in patients with HOCM undergoing septal myectomy, with EEA facilitating earlier tracheal extubation and shorter ICU stay without increasing perioperative cardiac morbidity or mortality 3.
Conscious Sedation for Electrophysiology Procedures
- Conscious sedation with intermittent midazolam and fentanyl has been shown to be safe and efficacious for electrophysiology procedures, with a low incidence of hypoxemia and hypotension 4.
- However, the use of midazolam for procedural sedation has been associated with respiratory events, particularly in older patients 5.
- Fentanyl has also been associated with hypotensive events, particularly when used in combination with home beta-blocker use 5.
Risks of Sedation in Patients with HOCM
- Severe benzodiazepine and opioid withdrawal can result in transient myocardial ischemia, highlighting the need for careful management of sedation and withdrawal syndromes in patients with HOCM 6.
- The use of sedation in patients with HOCM requires careful consideration of the potential risks and benefits, and close monitoring of blood pressure, heart rate, and cardiac function is essential to minimize the risk of complications 2, 3, 4, 5, 6.