Cardiomyopathy

Question 1

What are the chief characteristics of hypertrophic

cardiomyopathy?

Answer 1

Patients with hypertrophic cardiomyopathy typically suffer from
diastolic dysfunction which is exhibited by increased left
ventricular end-diastolic pressures despite an often
hyperdynamic left ventricular function. The diastolic stiffness is
due to the increased muscle mass of the left ventricle which is
typically concentrated in the upper septum just below the aortic
valve.
Butterworth JF, Mackey DC, Wasnick JD. Morgan & Mikhail’s
Clinical Anesthesiology. 5th ed. New York, NY: McGraw-Hill;
2013: 405.

Question 2

What are the symptoms of hypertrophic

cardiomyopathy?

Answer 2

Many patients are asymptomatic, but those that do exhibit
symptoms exhibit dyspnea on exertion, fatigue, syncope, or
angina. The first manifestation of hypertrophic cardiomyopathy
in patients younger than 30 years is often sudden cardiac
death, which is also the most common cause of death.
Butterworth JF, Mackey DC, Wasnick JD. Morgan & Mikhail’s
Clinical Anesthesiology. 5th ed. New York, NY: McGraw-Hill;
2013: 405-406.

Question 3

What are the anesthetic management goals for a

patient with hypertrophic cardiomyopathy?

Answer 3

Anesthetic goals include the minimization of sympathetic
activation to prevent sudden increases in cardiac contractility,
expansion of the intravascular volume to avoid hypovolemia,
and minimize decreases in left ventricular afterload. Some
degree of myocardial depression is often advantageous in these
patients and may be obtained through the use of volatile
inhalational agents and/or beta-adrenergic blocking agents.
Regional anesthesia may worsen the obstruction by decreasing
both preload and afterload.
Butterworth JF, Mackey DC, Wasnick JD. Morgan & Mikhail’s
Clinical Anesthesiology. 5th ed. New York, NY: McGraw-Hill;
2013: 405

Question 4

What type of cardiomyopathy is seen in patients with

aortic stenosis?

Answer 4

In aortic stenosis, the left ventricle must compensate for
increased mechanical impedance to ejection (increased
afterload). It does so by increasing the muscle mass of the left
ventricle known as concentric cardiomyopathy. The remodeling
of the ventricular muscle eventually results in decreased
compliance of the ventricle and a corresponding decrease in
contractility.
Nagelhout JJ, Plaus KL. Nurse Anesthesia. 5th ed. St. Louis,
MO: Elsevier Saunders Company; 2014: 501.

Question 5

What type of cardiomyopathy is typically seen in

patients with mitral regurgitation?

Answer 5

Eccentric hypertrophy is characteristic of mitral regurgitation.
Because of the incompetence of the mitral valve, the left
ventricle is exposed to a consistently increased volume of
blood. The ventricle compensates by increasing the left
ventricular chamber size.
Nagelhout JJ, Plaus KL. Nurse Anesthesia. 5th ed. St. Louis,
MO: Elsevier Saunders Company; 2014: 499.