PPESPVR is load dependent relationship of Peak LV pressure point at LV PV loop and ES point, also at LV PV loop. Both can be linearly linked and extended axis towards the declining pressure and volume leads to picking up Pressure at intercept with volume at intercept. Both P int. and V int. can be used to calculate parameters of systole during one cardiac cycle.

1. CHARACTERIZATION OF END SYSTOLE USING
END-SYSTOLIC FRACTION (ES F) % IN PRESSURE-
VOLUME LOOP
Linear relationship of LV Peak pressure (PP) to ESP/ESV (PPESPVR)
Filip Konecny

2. PPESPV RELATIONSHIP USING PV LOOP
Presented slides shows swine’s PV loop data collected from healthy baseline vs. dobutamine
challenge
PPESPVR in this slide-set indicates linear relationship of PP with ES (P and V) using PV loop
characteristics
LV volume (V@ PP) at the LV peak pressure is connected with ESV for the purpose to
characterize this relationship
Extending this linear relationship downwards and towards the volume axis, it captures the volume
intercept V int
(P int) identifies intercepting imaginary Volume (V int) using this linear PPESPV relationship
V int is an imaginary volume of LV chamber at given cardiac cycle, based on immediate V @PP
and ESV and particular (pre-and after-load)

3. PPESPV RELATIONSHIP USING PV LOOP
THE END SYSTOLIC FRACTION ES F (%)
When determining the Ejection Fraction (EF) such relationship characterizes more diastolic parameters in
cardiac cycle as for its denominator being EDV; PPESPVR can characterize volume relationship of LV during
systole as for its denominator (V@PP-V int)
This steady state parameter in PV loop might be able to characterize 2 states; ending systole and
(adjusted isovolumic relaxation phase) aIVR * and use end-systolic fraction ……ES F in (%), fraction of
imaginary volume of LV chamber during given cardiac cycle, based on V @PP and ESV at given cardiac
cycle and given an immediate (pre-and after-load)
Data can be captured without need of creating condition of load independence (Valsalva or surgical
venous pre-load maneuvers)
Data are later compared with dobutamine challenge using 20µg/kg/min infusion
Table at the end summarizes the data including IVR phase adjusted to P int.
* adjusted IVR phase in this example ESP to P int.

4. BASELINE
Slide describes baseline steady state PV relationship of Peak (PP) LV pressure to ESP-volume (PPESPVR). Recorded and derivative channels are as follows, ECG (in
mV), LV pressure (in mmHg), Channel 3 LV volume (in ml), Aortic pressure (in mmHg), channel 5 is HR in (bpm) and last channel is LVP derivative of channel 2 (LV
dp/dt in mmHg/sec). There are multiple time related events and relationships presented as for example: the end systole is captured by using dicrotic
notch seen on the aortic pressure trace at channel 4, which also corresponds to LV dp/dt min (at channel 6) and after-peak T wave ending at (channel 1). LV
volume at PP is shown on the channel 3 as red dotted line. Likewise, LV volume at ESP (ESV) is captured during ES (by solid red line), and also shown at channel 3
for comparison. The LV peak pressure (PP) is associated with LV volume that is still being ejected as LVP decreases from PP of 122.81 to ESP 81.1 mmHg to that is
(41.73 mmHg difference) within 85 msec. Both, exact volumes at PP (101.68 ml) and at ESV (84.49 ml) are shown at channels 3 and are blue color encircled.
Difference of volumes is 17.19 ml.

5. In healthy baseline example, volume at ESP (ESV) during ES can
be linearly connected with the LV volume at the LV peak
pressure. Extending PPESPVR linear relationship downwards to
the volume axis, it captures the intercept of this relationship (V
int). This imaginary volume occurs when LV pressure decreases to
(P int) in the LV.
To better understanding this relationship, the intercept V(int) can
be estimated to be about 50 ml (end of dotted line crossing the
volume axis). This relationship can generate simple equation of
ES PV to V (int) vs. V (PP) to V (int) , and with help from previous
slide hence:
ES F (%)=
𝐸𝑆𝑉−𝑉 (𝑖𝑛𝑡)
𝑉 (𝑃𝑃)−𝑉(𝑖𝑛𝑡)
=
84.49−50
101.68−50
=
34.49
51.68
= 66.7%
BASELINE
P (int)

6. Additionally, using this relationship to examine
LV pressure decay during baseline from PP to
ESP as compared to ESP to P int.
Shown in LV pressure channel recording PP to
ESP calculated 41.73 mmHg/ over 85 msec=
0.49
When ESP (81.1 mmHg) drops to P int (0.57
mmHg) the time is 100 msec (not shown). In this
example 81.1-0.57= 80.53 mmHg/ over 100
msec = 0.8
Hence during baseline condition the ratio of
pressure decay is faster during adjusted
isovolumic relaxation (IVR) phase as compared
to the end of ejection phase 0.8> 0.49
BASELINE

7. DOBUTAMINE CHALLENGE 20UG/KG/MIN
This slide describes steady state pressure-volume relationship of Peak (PP) LV pressure to ESP-volume (PPESPVR) during Dobutamine challenge. Recorded and
derivative channels are as follows, LV pressure (in mmHg), LV volume (in ml), channel 3 is HR in (bpm) and last channel is LVP derivative of channel 2 (LV dp/dt in
mmHg/sec). The end systole is captured by using LV dp/dt min (at channel 4). LV volume at PP is shown on the channel 2 as red dotted line. Likewise, LV
volume at ESP (ESV) and during ES are captured (by red dotted and solid line respectively). The LV peak pressure (PP) is associated with LV volume that is still
being ejected as LVP decreases from PP of 169.85 to 98.79 mmHg to ESP that is (71.06 mmHg difference) within 90 msec. Both, exact V @ PP (87.54 ml) and at
ESV (59.82 ml) are shown at channels 2 and are blue color encircled. Difference of volumes is 27.72 ml.

8. Furthermore in this example of dobutamine challenge, volume at
ESP (ESV) during ES might be linearly connected with the LV
volume at the LV peak pressure. When extending linear
PPESPVR downwards to the volume axis, it captures the intercept
V int of this relationship at P int. This imaginary volume occurring
when LV pressure decreases to P int in the LV.
To better understand this relationship, the intercept V(int) can
be estimated to be between 0 to 25ml est. to 23ml (
). This relationship can be generate simple equation of ES
PV to V (int) vs. V (PP) to V (int) , and with help from previous slide
hence:
ES F (%)=
𝐸𝑆𝑉−𝑉 (𝑖𝑛𝑡)
𝑉 (𝑃𝑃)−𝑉(𝑖𝑛𝑡)
=
59.82−23
87.54−23
=
36.82
64.54
= 57%
DOBUTAMINE CHALLENGE 20UG/KG/MIN
P (int)
Peak LV pressure
End Systolic
Pressure
V (int) ESV
V@ PP25

9. DOBUTAMINE CHALLENGE 20UG/KG/MIN
Using this relationship to examine LV pressure decay
during dobutamine challenge from PP to ESP as
compared to ESP to P int.
Shown in LV pressure channel recording PP to ESP
calculated 71.06mmHg/ over 90 msec= 0.79
When ESP (98.79 mmHg) drops to P int (5.031
mmHg) the time is 85 msec (not shown). Here in this
example 98.79- 5.031= 93.76 mmHg/ over 85
msec = 1.1
Hence during dobutamine challenge the ratio of
pressure decay is faster during LV isovolumic
relaxation (IVR) phase as compared to the ending of
ejection phase in the LV 1.1>0.79
(using P int and PPESPVR)
LV volume
at LV
peak
pressure
LV Volume (ESV) during ES at ESP

10. TABLE OF PPESPVR COMPARISON
PPESPVR ES F (%) HR (bpm) PP to ESP
(ending of systole)
(mmHg/msec)
ESP to P int.
(IVR phase adj.) *
(mmHg/msec)
Baseline 66.7 77 0.49 0.8
Dobutamine 57 135 0.79 1.1
* Adjusted IVR phase in this example ESP to P int.