Relation between pressure and volume unloading during ramp testing in patients supported with a continuous-flow left ventricular assist device

Mette H. Jung, Christian Hassager, Louise Balling, Stuart D. Russell, Soeren Boesgaard, Finn Gustafsson

Research output: Contribution to journalArticle

Abstract

Pulmonary capillary wedge pressure (PCWP) is the key to describing left ventricular (LV) unloading; however, the relation between pressure and the echocardiography-derived surrogate of LV volume (LV end-diastolic diameter [LVEDD]) as a function of pump speed (revolutions per minute [RPM]) in continuous-flow LV assist device (CF-LVAD) patients is unknown. In this study, the pressure-volume relation as a function of RPM during ramp testing was investigated by simultaneously measuring PCWP by Swan-Ganz catheter and LVEDD by echocardiography. The ramp protocol started at usual pump setting (ramp-base) and then went from 8,000 RPM (ramp-low) increasing by 400 RPM/5 minutes until reaching 12,000 RPM or suction/arrhythmic event (ramp-high). The study was finalized by a 25 Watt exercise test at two ramp steps. Ten patients with ramp-base of 9,300 ± 241 RPM (at which 3 of 10 had aortic valve opening) were examined. At ramp-low, ramp-base, and ramp-high, PCWP was 20 ± 4, 14 ± 4, and 7 ± 3 mm Hg (p <0.001 for all comparisons) and LVEDD 6.6 ± 1.0, 6.7 ± 0.9, and 5.5 ± 1.7 cm (p <0.05 for all comparisons but ramp-low versus ramp-base). Correlation between PCWP and LVEDD slopes; R 2 = 0.53 (p = 0.02). In conclusion, PCWP as a function of RPM is weakly correlated with changes in LVEDD. Thus, LVEDD is not an accurate measure of unloading in CF-LVAD patients.

Original languageEnglish (US)
Pages (from-to)307-312
Number of pages6
JournalASAIO Journal
Volume61
Issue number3
DOIs
StatePublished - Jul 20 2015

Fingerprint

Left ventricular assist devices
Architectural Accessibility
Heart-Assist Devices
Capillarity
Unloading
Pressure
Testing
Echocardiography
Pulmonary Wedge Pressure
Pumps
Catheters
Suction
Aortic Valve
Exercise Test
Stroke Volume

Keywords

  • assisted circulation physiology
  • heart failure
  • hemodynamics
  • left ventricular assist device

ASJC Scopus subject areas

  • Biophysics
  • Biomaterials
  • Bioengineering
  • Biomedical Engineering
  • Medicine(all)

Cite this

Relation between pressure and volume unloading during ramp testing in patients supported with a continuous-flow left ventricular assist device. / Jung, Mette H.; Hassager, Christian; Balling, Louise; Russell, Stuart D.; Boesgaard, Soeren; Gustafsson, Finn.

In: ASAIO Journal, Vol. 61, No. 3, 20.07.2015, p. 307-312.

Research output: Contribution to journalArticle

Jung, Mette H. ; Hassager, Christian ; Balling, Louise ; Russell, Stuart D. ; Boesgaard, Soeren ; Gustafsson, Finn. / Relation between pressure and volume unloading during ramp testing in patients supported with a continuous-flow left ventricular assist device. In: ASAIO Journal. 2015 ; Vol. 61, No. 3. pp. 307-312.
@article{78ccd6ba2c554c3d8880bd9d76deedc4,
title = "Relation between pressure and volume unloading during ramp testing in patients supported with a continuous-flow left ventricular assist device",
abstract = "Pulmonary capillary wedge pressure (PCWP) is the key to describing left ventricular (LV) unloading; however, the relation between pressure and the echocardiography-derived surrogate of LV volume (LV end-diastolic diameter [LVEDD]) as a function of pump speed (revolutions per minute [RPM]) in continuous-flow LV assist device (CF-LVAD) patients is unknown. In this study, the pressure-volume relation as a function of RPM during ramp testing was investigated by simultaneously measuring PCWP by Swan-Ganz catheter and LVEDD by echocardiography. The ramp protocol started at usual pump setting (ramp-base) and then went from 8,000 RPM (ramp-low) increasing by 400 RPM/5 minutes until reaching 12,000 RPM or suction/arrhythmic event (ramp-high). The study was finalized by a 25 Watt exercise test at two ramp steps. Ten patients with ramp-base of 9,300 ± 241 RPM (at which 3 of 10 had aortic valve opening) were examined. At ramp-low, ramp-base, and ramp-high, PCWP was 20 ± 4, 14 ± 4, and 7 ± 3 mm Hg (p <0.001 for all comparisons) and LVEDD 6.6 ± 1.0, 6.7 ± 0.9, and 5.5 ± 1.7 cm (p <0.05 for all comparisons but ramp-low versus ramp-base). Correlation between PCWP and LVEDD slopes; R 2 = 0.53 (p = 0.02). In conclusion, PCWP as a function of RPM is weakly correlated with changes in LVEDD. Thus, LVEDD is not an accurate measure of unloading in CF-LVAD patients.",
keywords = "assisted circulation physiology, heart failure, hemodynamics, left ventricular assist device",
author = "Jung, {Mette H.} and Christian Hassager and Louise Balling and Russell, {Stuart D.} and Soeren Boesgaard and Finn Gustafsson",
year = "2015",
month = "7",
day = "20",
doi = "10.1097/MAT.0000000000000194",
language = "English (US)",
volume = "61",
pages = "307--312",
journal = "ASAIO Journal",
issn = "1058-2916",
publisher = "Lippincott Williams and Wilkins",
number = "3",

}

TY - JOUR

T1 - Relation between pressure and volume unloading during ramp testing in patients supported with a continuous-flow left ventricular assist device

AU - Jung, Mette H.

AU - Hassager, Christian

AU - Balling, Louise

AU - Russell, Stuart D.

AU - Boesgaard, Soeren

AU - Gustafsson, Finn

PY - 2015/7/20

Y1 - 2015/7/20

N2 - Pulmonary capillary wedge pressure (PCWP) is the key to describing left ventricular (LV) unloading; however, the relation between pressure and the echocardiography-derived surrogate of LV volume (LV end-diastolic diameter [LVEDD]) as a function of pump speed (revolutions per minute [RPM]) in continuous-flow LV assist device (CF-LVAD) patients is unknown. In this study, the pressure-volume relation as a function of RPM during ramp testing was investigated by simultaneously measuring PCWP by Swan-Ganz catheter and LVEDD by echocardiography. The ramp protocol started at usual pump setting (ramp-base) and then went from 8,000 RPM (ramp-low) increasing by 400 RPM/5 minutes until reaching 12,000 RPM or suction/arrhythmic event (ramp-high). The study was finalized by a 25 Watt exercise test at two ramp steps. Ten patients with ramp-base of 9,300 ± 241 RPM (at which 3 of 10 had aortic valve opening) were examined. At ramp-low, ramp-base, and ramp-high, PCWP was 20 ± 4, 14 ± 4, and 7 ± 3 mm Hg (p <0.001 for all comparisons) and LVEDD 6.6 ± 1.0, 6.7 ± 0.9, and 5.5 ± 1.7 cm (p <0.05 for all comparisons but ramp-low versus ramp-base). Correlation between PCWP and LVEDD slopes; R 2 = 0.53 (p = 0.02). In conclusion, PCWP as a function of RPM is weakly correlated with changes in LVEDD. Thus, LVEDD is not an accurate measure of unloading in CF-LVAD patients.

AB - Pulmonary capillary wedge pressure (PCWP) is the key to describing left ventricular (LV) unloading; however, the relation between pressure and the echocardiography-derived surrogate of LV volume (LV end-diastolic diameter [LVEDD]) as a function of pump speed (revolutions per minute [RPM]) in continuous-flow LV assist device (CF-LVAD) patients is unknown. In this study, the pressure-volume relation as a function of RPM during ramp testing was investigated by simultaneously measuring PCWP by Swan-Ganz catheter and LVEDD by echocardiography. The ramp protocol started at usual pump setting (ramp-base) and then went from 8,000 RPM (ramp-low) increasing by 400 RPM/5 minutes until reaching 12,000 RPM or suction/arrhythmic event (ramp-high). The study was finalized by a 25 Watt exercise test at two ramp steps. Ten patients with ramp-base of 9,300 ± 241 RPM (at which 3 of 10 had aortic valve opening) were examined. At ramp-low, ramp-base, and ramp-high, PCWP was 20 ± 4, 14 ± 4, and 7 ± 3 mm Hg (p <0.001 for all comparisons) and LVEDD 6.6 ± 1.0, 6.7 ± 0.9, and 5.5 ± 1.7 cm (p <0.05 for all comparisons but ramp-low versus ramp-base). Correlation between PCWP and LVEDD slopes; R 2 = 0.53 (p = 0.02). In conclusion, PCWP as a function of RPM is weakly correlated with changes in LVEDD. Thus, LVEDD is not an accurate measure of unloading in CF-LVAD patients.

KW - assisted circulation physiology

KW - heart failure

KW - hemodynamics

KW - left ventricular assist device

UR - http://www.scopus.com/inward/record.url?scp=84937632102&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84937632102&partnerID=8YFLogxK

U2 - 10.1097/MAT.0000000000000194

DO - 10.1097/MAT.0000000000000194

M3 - Article

C2 - 25485566

AN - SCOPUS:84937632102

VL - 61

SP - 307

EP - 312

JO - ASAIO Journal

JF - ASAIO Journal

SN - 1058-2916

IS - 3

ER -