Introduction
Methods
Patient selection
EXERCISE | DIP | PACING | |
---|---|---|---|
PT n° | 49 | 31 | 8 |
Age (years) | 58 ± 13 | 66 ± 11 | 71 ± 10 |
Males | 33 | 17 | 6 |
Controls | 9 | 0 | 0 |
Previous PTCA/By pass | 15 | 15 | 2 |
Previous myocardial infarction | 12 | 8 | 2 |
Arterial hypertension | 27 | 17 | 5 |
Atypical chest pain/miscellaneous | 13 | 10 | 4 |
BB on | 21 | 17 | 5 |
ACEi on | 11 | 10 | 5 |
Ca CB on | 11 | 8 | 1 |
Semi-supine bicycle exercise
Dipyridamole stress echo
Pacing stress echo
Diagnostic end points and interruption criteria
Data acquisition
Regional wall motion analysis
Blood pressure analysis
End-systolic pressure-volume determination
Arterial elastance and ventricular-arterial coupling
Systemic Vascular Resistance (SVR)
Systemic arterial compliance
The cardiac force measurement by the precordial cutaneous sensor and the operator-independent force-frequency relation
Statistical analysis
Results
Resting and stress echocardiographic findings
At Peak Exercise
EXERCISE | DIP | PM stress | |
---|---|---|---|
N of pts | 49 | 31 | 8 |
Age (yrs) | 58 ± 13 § | 66 ± 11 | 71 ± 10 |
Gender (M/F) | 33/16 | 17/14 | 6/2 |
BSA (m2) | 1.86 ± .20 | 1.78 ± .16 | 1.89 ± .25 |
Standard echo measurements
| |||
LVMI (g/m2) | 104 ± 30 | 104 ± 20 | 138 ± 35 |
HR rest (bpm) | 72 ± 15 | 68 ± 12 | 71 ± 10 |
HR peak (bpm) | 130 ± 21Δ | 86 ± 15* | 130 ± 12 |
Δ HR (rest-peak, bpm) | 59 ± 20Δ | 18 ± 13* | 59 ± 14 |
LV EF % rest | 59 ± 10 | 59 ± 10 | 51 ± 10 |
LV EF % peak | 65 ± 12‡ | 64 ± 11* | 49 ± 16 |
Δ LV EF % (rest-peak) | 6 ± 7‡ | 5 ± 7 | -2 ± 10 |
WMSI rest | 1.08 ± .22 | 1.11 ± .24 | 1.21 ± .41 |
WMSI peak | 1.10 ± .26 | 1.12 ± .24 | 1.32 ± .44 |
Δ WMSI (rest-peak) | .03 ± .13 | .01 ± .06 | .11 ± .22 |
FFR with echocardiography (SP/ESVi)
| |||
SP/ESV index rest (mmHg/mL/m2) | 7.6 ± 4.6 | 7.3 ± 2.6 | 6.3 ± 4.3 |
SP/ESV index peak (mmHg/mL/m2) | 14.7 ± 8.4Δ | 8.3 ± 3.5 | 10.3 ± 8.1 |
Δ SP/ESV index (rest-peak) | 7.1 ± 5.4Δ | 1 ± 2.1 | 3.9 ± 4 |
Δ SP/ESV index % (rest-peak) | 103 ± 74§ | 13 ± 26 | 49 ± 37 |
Sensor built FFR (isovolumic vibrations)
| |||
Force rest (g * 10-3) | 10 ± 4.7 | 12.3 ± 6.1 | 9.5 ± 4.5 |
Force peak (g * 10-3) | 36 ± 18.7§ | 15.3 ± 8.1 | 15.2 ± 5.6 |
Δ Force (rest-peak, g * 10-3) | 26 ± 16.7§ | 3 ± 5 | 5.7 ± 4.4 |
Δ Force % (rest-peak) | 275 ± 132§ | 28 ± 39 | 74 ± 52 |
Peripheral pressures, load and coupling
| |||
SBP rest (mmHg) | 133 ± 24 | 138 ± 23 | 141 ± 29 |
SBP peak (mmHg) | 189 ± 26§ | 131 ± 27 | 144 ± 34 |
Δ SBP % (rest-peak) | 45 ± 20§ | -5 ± 12 | 2 ± 12 |
SVR rest (dyne * sec * cm-5) | 2004 ± 740 | 2076 ± 649 | 2161 ± 1163 |
SVR peak (dyne * sec * cm-5) | 1472 ± 464 | 1500 ± 636 | 1809 ± 737 |
Arterial compliance rest (mL *m-2/mmHg) | 0.51 ± 0.19 | 0.48 ± 0.15 | 0.58 ± 0.40 |
Arterial compliance peak (mL *m-2/mmHg) | 0.33 ± 0.12Δ | 0.54 ± 0.20* | 0.35 ± 0.19 |
Δ Arterial compliance % (rest-peak) | -31 ± 26Δ | 18 ± 32* | -31 ± 27 |
Arterial elastance index rest (mmHg/mL/m2) | 4.4 ± 1.4 | 4.4 ± 1.1 | 4.7 ± 2.7 |
Arterial elastance index peak (mmHg/mL/m2) | 6.2 ± 2Δ | 3.9 ± 1.3* | 7.3 ± 2.9 |
Δ Arterial elastance index % (rest-peak) | 47 ± 47Δ | -10 ± 23* | 62 ± 41 |
Ventricular/arterial coupling rest (SP/ESV/EaI ratio) | 1.7 ± .7 | 1.7 ± .8 | 1.3 ± .7 |
Ventricular/arterial coupling peak (SP/ESV/EaI ratio) | 2.5 ± 1.3‡ | 2.3 ± 1.2 | 1.3 ± .9 |
Δ Ventricular/arterial coupling % (rest-peak) | 48 ± 65‡ | 31 ± 37 | -2 ± 40 |
Cardiac index rest (L/min/m2) | 2.1 ± 0.6 | 2 ± 0.4 | 2.4 ± 0.8 |
Cardiac index peak (L/min/m2) | 3.9 ± 1.1§ | 2.8 ± 0.9 | 2.7 ± 0.8 |
Δ Cardiac index % (rest-peak) | 99 ± 62§ | 37 ± 32 | 14 ± 22 |
DBP rest (mmHg) | 71 ± 11 | 71 ± 13 | 77 ± 11 |
DBP peak (mmHg) | 93 ± 13§ | 68 ± 12 | 80 ± 16 |
Δ DBP % (rest-peak) | 31 ± 20§ | -4 ± 13 | 4 ± 18 |
LV EDV index rest (mL/m2) | 51 ± 16 | 50 ± 11 | 65 ± 32 |
LV EDV index peak (mL/m2) | 47 ± 14 | 50 ± 13 | 47 ± 30 |
Δ EDV index % (rest-peak) | -7 ± 16‡ | -1 ± 12* | -30 ± 12 |
Contractile response to stress
Peripheral pressures, load and coupling
Sensor built force-frequency relation
Rest Force | Peak Force | FFR Δ rest-peak | FFR Δ % rest-peak | |
---|---|---|---|---|
Age (yrs) | -0.53 | -0.52 | -0.43 | |
BSA (m2) | ||||
LVMI (g/m2) | ||||
LV EF % | 0.38 | 0.27 | 0.19 | 0.23 |
WMSI | -0.19 | |||
HR (bpm) | 0.58 | 0.63 | 0.57 | |
SP/ESV index (mmHg/mL/m2) | 0.34 | 0.36 | 0.49 | 0.57 |
Cardiac index (L/min/m2) | 0.41 | 0.45 | 0.44 | |
Ventricular/arterial coupling | 0.38 | 0.21 | 0.18 | 0.22 |
LV EDV index (mL/m2) |
Discussion
The sensor built force-frequency relation
Ultrasound | Sound | |
---|---|---|
Diagnostic vibrations | artificial | spontaneous |
Imaging | yes | no |
Wiggers cycle | ejection phase | isovolumic contraction |
LV volumes needed | yes | no |
Systolic pressure needed | yes | no |
Hardware needed | 2-D echo | accelerometer |
Force display | off-line | on-line |
Portability | difficult | simple |
Remote transmission | difficult | simple |