Hypertrophic Cardiomyopathy (HCM)

Hemodynamic goals - Think full, slow, and tight: maintain preload (avoid hypovolemia and venodilation), keep the rate slow-to-normal to allow diastolic filling, and preserve afterload (systemic vascular resistance). Anything that empties, speeds, or underfills the ventricle worsens the outflow obstruction.

Treat hypotension with a pure alpha agent - Use phenylephrine or vasopressin, not ephedrine or other beta agonists - raising contractility or heart rate deepens the LVOT gradient. Give volume and restore afterload first; reach for an inotrope essentially never.

Avoid tachycardia and light anesthesia - Blunt laryngoscopy, ensure adequate depth, and treat pain; continue home beta-blockers or calcium-channel blockers, which lower contractility and the gradient.

Maintain sinus rhythm - The atrial kick matters with a stiff, noncompliant ventricle; treat new atrial fibrillation aggressively, often with cardioversion. Have a defibrillator ready - many patients carry an ICD.

Neuraxial caution - A single-shot spinal's abrupt sympathectomy drops preload and afterload and can be catastrophic; a slowly titrated epidural with vigilant preload and SVR support is safer.

Interpreting hypotension - A new systolic murmur or unexplained hypotension suggests worsening obstruction - correct with volume, phenylephrine, a slower rate, and deeper anesthesia, NOT with an inotrope.

An autosomal dominant sarcomere-protein mutation producing left ventricular hypertrophy, classically asymmetric septal thickening. The consequences are a DYNAMIC left ventricular outflow tract (LVOT) obstruction (worsened by systolic anterior motion of the mitral valve), diastolic dysfunction from a stiff ventricle, myocardial ischemia, mitral regurgitation, arrhythmias, and a real risk of sudden cardiac death - especially in young patients and athletes. The defining anesthetic point is that the obstruction is dynamic: increased contractility, a low preload, a fast heart rate, or a fall in afterload all worsen the gradient. The whole anesthetic is built around not doing those things.