HOCM gradients & considerations

Question 1

What is the most common variation of HOCM?

Answer 1

Sigmoidal HOCM

40-50%

Question 2

What are the 4 common variants of HOCM?

Answer 2

1. Sigmoidal (40-50%)
2. Reverse Curve (30-40%)
3. Apical (10%)
4. Neutral (10%)

Question 3

In addition to Enlarged Septum, what other 2 factors contribute to obstruction of the LVOT in HOCM?

Answer 3

1. Elongated leaflet
2. Apically displaced papillary muscle

Question 4

What is the classic color wave doppler of HOCM and LVOT obstruction?

Answer 4

Late systolic peaking

AKA “Lobster claw” or “Dagger”

Question 5

When you have an LVOTO patient, what are the 3 gradients to keep in mind?

Answer 5

1. Subaortic Gradient
2. Papillary muscles
3. Apical Gradient (Diastole)

Question 6

What is the resting LVOT gradient on TTE which goes directly to surgical candidacy?

Answer 6

>50 mmHg

Significant SAM / MR (posterior)

Question 7

If patient has a resting LVOT <50 mmHg, what valsalva pressure threshold would trigger a surgical consult?

Answer 7

>30 mmhg

+/-

SAM/MR

Question 8

What do you have to obtain the OR prior to surgical stimulation after you induce a HOCM patient?

Answer 8

Resting gradients (Pre CPB)

Question 9

After achieving a resting post induction LVOT gradient before CPB, what needs to be performed?

Answer 9

Dobutamine to provoke the LVOT

Question 10

After coming off bypass, what needs to be done when evaluating HOCM?

Answer 10

Post CPB Provocation

Question 11

What is the threshold for LVOT gradients post CPB after pharmacological stress test for LVOT gradient?

Answer 11

>30 mmHg +/- Significant SAM/MR

Question 12

When performing an alcohol ablation, what do they do?

Answer 12

Inject ETOH into septal perforator to cause necrosis fo the septal basal portion

Question 13

How does the pharmacological stress provocaation estimate LVOT gradients?

Answer 13

overestimates