1. The document analyzes left ventricular pressure and aortic blood flow data collected from a large animal model under baseline conditions and during dobutamine stress. 2. One cardiac cycle is represented as a pressure-flow loop on a graph of left ventricular pressure versus aortic blood flow. Data from 10 cardiac cycles are analyzed for each condition. 3. Key cardiac cycle intervals - isovolumic contraction time, ejection time, and isovolumic relaxation plus filling time - are significantly different between baseline and dobutamine stress conditions based on statistical analysis.

1. BLOOD PRESSURE-FLOW LOOP
INVASIVE LEFT VENTRICULAR PRESSURE AND
AORTIC BLOOD FLOW (PART 2)
The invasive left ventricular pressure, aortic blood flow relationship during baseline & under Dobutamine stress challenge in large animal model
Filip Konecny
1

2. Left ventricular pressure plotted versus the Aortic blood flow; data collected during baselines (200 samples/sec)
Utilizing max dp/dt and the Aortic pressure notch (the end systole) as description of the LV Ejection phase
One cardiac cycle composed from pressure vs. Ao blood flow creating pressure flow loop on the right
Ejection phase of pressure-flow loop from blue triangle to blue square with its path shown as a square dotted line
Overview
Left ventricular
Pressure trace (mmHg)
Aortic blood pressure trace
(mmHg)
Aortic blood flow (l/min)
dp/dt (mmHg/s)
2

3. 3
Left ventricular
pressure
trace (mmHg)
Aortic blood
flow (l/min)
dp/dt
(mmHg/s)
Using LVP vs. Ao Blood flow traces, selected is the LV ejection on the LVP (using max and min dp/dt). One ejection
cycle’s mean dV/dt shown in red circle as an individual dV/dt (ml/min/s). Final Table 1 at slide 5 shows 10 dv/dt
(SV) during consecutive ejection cycles
Data collected during Baseline

4. 4
Left ventricular
pressure
trace (mmHg)
Aortic blood
flow (l/min)
dp/dt
(mmHg/s)
Using LVP vs. Ao Blood flow traces, selected is the LV ejection on the LVP (using max and min dp/dt). One
ejection cycle’s mean dV/dt shown in red circle as an individual dV/dt (ml/min/s). Final Table 1 at slide 5 shows
10 dv/dt (SV) during consecutive ejection cycles
Data collected during Dobutamine stress at (5µg/kg/min)

5. 5
Cardiac Ejection BSL Mean dV/dt BSL dp/dt max BSL dp/dt min DOBU Mean dV/dt DOBU dp/dt max DOBU dp/dt min
Ejection 1 8.118 1341 1318 12.012 3648 1798
Ejection 2 6.505 1316 1405 12.245 3661 2087
Ejection 3 7.548 1322 1445 12.49 3636 1773
Ejection 4 10.923 1308 1238 13.639 3595 1865
Ejection 5 10.32 1337 1288 13.444 3665 1674
Ejection 6 11.117 1194 1213 11.624 3606 1850
Ejection 7 11.652 1242 1270 13.827 3641 1887
Ejection 8 10.667 1124 1173 12.145 3665 1904
Ejection 9 7.221 1162 1263 12.281 3416 1881
Ejection 10 6.029 1261 1284 10.582 3732 2199
Mean 9.010 1260.700 1289.700 12.429 3626.500 1891.800
SD 2.1 77.9 82.7 1.0 82.8 151.1
Mean HR 114 bpm 155 bpm
T test 0.00052409 7.75652E-23 2.77858E-08
Table 1 captures mean dV/dt during ejection
time (ET) selected by dp/dt data from
Baseline and Dobutamine 5µg/kg. Data are
taken from 10 consecutive cardiac beats at
specified HR, T test results are shown below
the table.

6. PHASES OF AO BLOOD FLOW WAVE AT (BASELINE)
6
Isovolumic Contraction time (IVCT) Ejection time (ET)
From the dpdt max to dpdt min (ET)…..180 msecFrom the R-wave on ECG to dp/dt max (IVCT)…..30 msec
Isovolumic Relaxation time (IVRT) and Filling time
From the dpdt min to R wave (IVRT)….320 msec

7. 7
Isovolumic Contraction time (IVCT) Ejection time (ET)
From the dpdt max to dpdt min (ET)…..150 msecFrom the R-wave on ECG to dp/dt max (IVCT)…..10 msec
Isovolumic Relaxation time (IVRT) and Filling time
Dobutamine 5µg/kg
From the dpdt min to R wave (IVRT)….360 msec
PHASES OF AO BLOOD FLOW WAVE DURING (DOBU)

8. 8
Table 2 captures cardiac cycle intervals IVCT, ET and IVRT+fill time; data are from Baseline
and Dobutamine 5µg/kg; taken from 10 consecutive cardiac cycles at specified HR, T test
results are shown below the table.
BSL Dobutamine
Cardiac Cycle IVCT (msec) ET (msec)
IVRT+ fill
(msec) IVCT (msec) ET (msec)
IVRT+ fill
(msec)
Cycle 1 30 200 310 10 165 355
Cycle 2 30 190 320 15 150 360
Cycle 3 35 190 315 10 150 365
Cycle 4 30 175 325 15 150 365
Cycle 5 35 185 315 10 165 355
Cycle 6 35 175 330 10 145 370
Cycle 7 30 180 315 10 145 365
Cycle 8 30 195 310 10 155 360
Cycle 9 30 190 320 10 160 350
Cycle 10 30 190 310 10 150 365
Mean 32 187 317 11 154 361
SD 2.4 8.2 6.7 2.1 7.5 6.1
Mean HR 118 bpm 160 bpm
T test 1.14896E-13 2.0331E-08 1.1302E-11