echo findings
What are 2 ways to differ between AS and MR Doppler waveforms?
- AS jet begins after IVCT and ends before IVRT
- AS will have a sharper, more triangular appearance
- MR is typically higher velocity
What murmur might be heard with severe AI?
Austin flint murmur
rumbling diastolic murmur, best heart at the apex of the heart (~5th intercostal space at the midclavicular line)
What is the most common type of AS? Where on the AoV does it originate?
degenerative, at the annulus
How do we grade AS, using the mean gradient?
mild = <20mmHg
moderate = 20-40mmHg
severe = >40mmHg
What is the regurgitant volume equation?
regurgitant volume = SVav - SVmv
mild = <30 mL/beat
moderate = 30-59 mL/ beat
severe = > 60 mL/beat
*The presence of severe MR will produce inaccurate results
Name 3 things we may wee on M-Mode with AS.
- thickened cusps
- decreased excursion
- eccentric closure line (bicuspid)
- LVH
- LA enlargement
- dilation of the aortic root
left ventricular hypertrophy
Name 2 treatment options for AI.
- beta blockers
- vasodilators
- antiarrhythmic therapy
- diuretics
- avoidance of heavy physical exertions
- AoV repair/ replacement
*focus is on reducing afterload
How do we grade AI, using the pressure half-time?
mild = >500msec
moderate = 500-200msec
severe = <200msec
What is the EROA equation?
EROA = AVregurgitant volume / AIVTI
mild = <0.1cm2
moderate = 0.1-0.29cm2
severe = >0.3cm2
Describe what we might see in the descending and/or abdominal aorta in the presence of significant AI.
holodiastolic flow reversal
(VTI >15cm in the descending aorta or any holodiastolic flow reversal in the abdominal aorta)
- angina
- dyspnea/ paroxysmal nocturnal dyspnea
- CHF
- syncope
- SOB
- palpitations
- narrow pulse pressure
- parvus et tardus
Describe aortic sclerosis.
- calcification and thickening of the aortic valve, without obstruction of flow
- the start of AS
How do we grade AS, using the peak velocity?
sclerosis = <2.5m/s
mild = 2.6-2.9m/s
moderate = 3.0-4.0m/s
severe = >4.0m/s
What is the AVA equation?
AVA = (0.785(LVOTdiameter2 * LVOTVTI)) / AoVVTI
mild = >1.5cm2
moderate = 1.0-1.5cm2
severe = <1.0cm2
Describe how severe AS can lead to PHTN.
severe AS -> increased afterload -> LV hypertrophy -> increased LVEDP -> increased LAP (to ensure LV filling) -> backup into the right heart -> PHTN
What happens to blood pressure in the presence of AI?
Increased systolic BP, decreased diastolic BP (wide pulse pressure)
- increased systolic because the heart has to increase SV in order to maintain cardiac output
- decreased diastolic because of the retrograde diastolic flow
Describe the difference between compensation and decompensation.
Compensation: the heart's ability to make changes in order to maintain adequate blood flow (chronic, severe AI)
Decompensation: the inability of the heart to make changes fast enough to maintain adequate blood flow (acute, severe AI)
How do we grade AI, using the vena contracta?
mild = <0.3cm
moderate = 0.3=0.7cm
severe = >0.7cm
What is the regurgitant fraction equation?
(SVAV - SVMV) / SVAV
mild = <30%
moderate = 30-49%
severe = >50%
Explain why we will see a steep waveform pattern with severe AI.
The larger the opening during diastole, the faster the blood will flow back into the left ventricle. This causes a faster decrease in aortic pressure and a steep waveform
Describe the murmur produced by AS.
- high-pitched crescendo-decrescendo, mid-systolic ejection murmur
- heard at the right upper sternal border
- radiates into the neck and carotid arteries
*as the disease progresses, the peak moves later through systole
Name 2 congenital causes of AI.
- uni/bi/quad cuspid valve
- VSD
- Ehlers-Danlos syndrome
- Marfan's syndrome
A patient has a peak velocity of 3.1m/sec, a mean gradient of 38mmHg, and an AVA of 1.3cm2.
How would you grade their aortic stenosis?
moderate stenosis
How do you calculate the stroke volume of the aortic valve?
SVAV = CSA * VTIAV