LVP and Ao

Question 1

Normal LVP pressure waveform

Answer 1

systolic, diastolic + end diastolic

Question 2

Changes with outflow obstruction

Answer 2

Systolic PG → valvular/sub/supra

Question 3

Normal AoP curve

Answer 3

systolic peak, dicrotic notch, diastolic

Question 4

types of PG measurements

Answer 4

instantaneous, peak to peak, mean P difference

 Diastolic PG across AV valve or systolic PG across semilunar v.

o Valve stenosis: ↑ flow from ↑ pressure behind stenosis

Question 5

Effect of general anesthesia on PG

Answer 5

General anesthesia ↓ PG 40-50%

Question 6

What factors can affect PG

Answer 6

Depend on trans valvular flow → affected by HF, anesthetics, hypovolemia, arrhythmia, other lesions ↓ flow

Question 7

Effect of isoproterenol stim on normal heart

Answer 7

β agonist (β1 + β2)
* Base: no LVOT obstruction
* Iso-1: PG = 40mmHg across LVOT
* Iso-2: PG = 65mmHg across LVOT
o ↑contractility → ↑obstruction = dynamic/progressive LVOTO
o Patients w HCM: can have labile LVOTO
o Septal reduction: considered if PG >50mmHg at rest or during provocation/exercise

Question 8

Fixed SAS: AoP curve

Answer 8

• Obstruction throughout entire systole: starts at AoV opening → closure
• Aortic pressure: slow rate of rise
  o Start early systole → entire ejection period

Question 9

Fixed SAS: LVP curve

Answer 9

symmetric shape, peak in mid systole
o Largest PG in early systole

Question 10

Dynamic LVOTO secondary to HCM: AoP curve

Answer 10

rapid upstroke in early systole → flat
o Rapid ventricular ejection → doming due to dynamic obstruction
o Characteristic “spike and dome” → bifid pulse

Question 11

Dynamic LVOTO secondary to HCM: LVP curve

Answer 11

rapid upstroke is late when maximal obstruction = at end systole

Question 12

Brockenbrough-Braunwald sign

Answer 12

o Narrowing pulse pressure w spike/dome appearance after Valsalva/VPC
o After compensatory pause from VPC → drop in Ao pulse
 Fixed obstruction: ↑ contractile force post VPC beat → ↑LV + AoP → ↑CO → ↑pulse width
 Dynamic obstruction: ↑ contractile force worsen → ↑ degree of obstruction → ↑LVP but ↓AoP → ↓ pulse pressure

Question 13

Intermittent obstruction

Answer 13

• Obstructions can be intermittent
  o Minimal or no PG at rest
  o Provocative maneuvers can be considered to provoke PG
   ↓pre/afterload: nitrates
   ↑contractility: isoproterenol
• Excessive inotropic stimulation may provoke gradients in normal hearts
   Induce VPC w KT in RV/LV
   Valsalva maneuver: ↑ intrathoracic P → ↓ preload → ↑ obstruction

Question 14

Systolic anterior motion of MV

Answer 14

• Acceleration of blood flow across LVOT in systole → push MV leaflets in LVOT
• Dynamic component → peak PG is delayed until late systole
  o LV pressure contour ↑ in late systole