Info

Oil +ft

Figure 3 Panel A. Apical 2 chamber view of a bileaflet valve prosthesis in the mitral orifice, implanted in the anti-anatomical orientation (hinge line perpendicular to the interventricular septum). In the 2 chamber view during diastole the two leaflets can separately be discerned.

Figure 3 Panel B. Apical 4-chamber, two dimensional Doppler recording of the left ventricular spatial flow pattern caused by a bileaflet valve prosthesis inserted in the anti-anatomical orientation. In the vicinity of the valve prosthesis, a red flow stream is recorded, indicating blood motion towards the transducer. Mid ventricular, a blue colour is recorded, indicating blood motion away from the transducer. In the apex again a red colour is recorded, indicating blood motion in the direction of the transducer. The left ventricular spatial flow pattern is characterised by three layers of blood motion: two layers of blood moving towards the apex (one along the anterior wall and one along the posterior wall) with one layer of blood moving towards the cardiac base in between. This bloodstream may enter the outflow tract unimpeded. The Doppler recording results from a scanplane that cuts trough the three separate layers.

Figure 4A. Apical 4-chamber view of a interventricular septum instead of towards the

Figure 4B. The blood stream through the valve is deviated towards the interventricular septum and hence a spatial flow pattern results that can be characterised by a clockwise rotating

Panel (6-11-'96) recording early after aortic valve replacement for congenital aortic stenosis (peak gradient 16 mmHg). The closing of the valve, encompass the flow velocity recording (arrow A) Closure backflow

Panel (15-I-'97). Doppler recording after this patient admitted himself with complaints o) dizziness. Oral anticoagulant therapy was stopped after a visit to the dentist. The peak gradient had increased to 96 mmHg. A clear delay existed between end systole (stop blood motion) and closure of the valve prosthesis (arrow A). A closure backflow could obviously

Panel 26-2- '97. After operation and cleaning of the valve prosthesis, a peak gradient of 25 mmHg was recorded. Opening and closing artefacts encompass the flow velocity recording again

(arrow A) and a closure backflow could no longer be recorded.

Figure 5. Continuous Wave Doppler recordings of blood flow through a Medtronic Hall aortic valve prosthesis

Figure 6. Transesophageal continuous wave Doppler recording of blood flow across a mitral disc valve prosthesis obstructed by thrombus formation. The mean gradient approaches the peak gradient. This caused by a decreased cardiac output, in combination with a pressure difference between left atrium and left ventricle that remains almost the same during diastole.

Figure 6. Transesophageal continuous wave Doppler recording of blood flow across a mitral disc valve prosthesis obstructed by thrombus formation. The mean gradient approaches the peak gradient. This caused by a decreased cardiac output, in combination with a pressure difference between left atrium and left ventricle that remains almost the same during diastole.

Was this article helpful?

0 0

Post a comment