Page 293 - Hall et al (2015) Principles of Critical Care-McGraw-Hill

CHAPTER 28: Interpretation of Hemodynamic Waveforms 197

60

v
40

20
Balloon deflated

S
60
v
40

20
Catheter retracted

FIGURE 28-23. Top, inadvertent wedging (balloon deflated) in a patient with a prominent v wave. Bottom, pulmonary artery pressure (Ppa) tracing after catheter is retracted.
Misinterpretation of the top tracing as a Ppa tracing could result in pulmonary artery rupture upon balloon inflation. Scale in millimeters of mercury.
Large v waves are not always indicative of mitral insufficiency. The size dilated, severe valvular regurgitation may give rise to a trivial v wave
of the v wave depends on both the volume of blood entering the atrium (Fig. 28-25). The important effect of left atrial compliance on the size
49
during ventricular systole and left atrial compliance. 48,49 Decreased left of the v wave was demonstrated by a study that simultaneously evaluated
atrial compliance may result in a prominent v wave in the absence of the height of the v wave and the degree of regurgitation, as determined
49
mitral regurgitation (Fig. 28-24). Conversely, when the left atrium is by ventriculography. Of patients who had large (>10 mm Hg) v waves,
A II 0.5-40 Hz B

Ppw
40 v
36 a
32
28
24
20
16
12
8 P
4 Baseline 25 mm/s
0 Pressure
II 0.5-40 Hz
V
Ppw P
30
27 V
24
21
18 a v
15
12
9 Volume
6
3
0 Post ultrafiltration 25 mm/s
FIGURE 28-24. Prominent v waves in the absence of mitral regurgitation. A. Pulmonary artery wedge pressure (Ppw) tracing before and after ultrafiltration. B. Left atrial pressure-volume
relationship. The same degree of passive filling during diastole (ΔV) produces a much larger change in pressure (ΔP) when the left atrium is operating on the steep portion of the compliance
curve, explaining the presence of a large v wave with hypervolemia. Scale in millimeters of mercury.

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