Effects of left ventricular unloading by Impella recover LP2.5 on coronary hemodynamics.
OBJECTIVE
We studied the effects of LV unloading by the Impella on coronary hemodynamics by simultaneously measuring intracoronary pressure and flow and the derived parameters fractional flow reserve (FFR), coronary flow velocity reserve (CFVR), and coronary microvascular resistance (MR).


BACKGROUND
Patients with compromised left ventricular (LV) function undergoing high-risk percutaneous coronary intervention (PCI) may benefit from LV unloading. Limited information is available on the effects of LV unloading on coronary hemodynamics.


METHODS
Eleven patients (mean LV ejection fraction of 35 +/- 11%) underwent PCI during LV support by the LV unloading device (Impella Recover LP2.5). Intracoronary measurements were performed in a nonstenotic coronary artery after the PCI, before and after adenosine-induced hyperemia at four different support levels (0-2.5 L/min).


RESULTS
Aortic and coronary pressure increased with increasing support levels, whereas FFR remained unchanged. Baseline flow velocity remained unchanged, while hyperemic flow velocity and CFVR increased significantly with increasing support levels (61 +/- 24 to 72 +/- 27 cm/sec, P = 0.001 and 1.88 +/- 0.52 to 2.34 +/- 0.63, P < 0.001 respectively). The difference between baseline MR and hyperemic MR significantly increased with increasing support levels (1.28 +/- 1.32 to 1.89 +/- 1.43 mm Hg cm(-1) sec, P = 0.005).


CONCLUSIONS
Unloading of the LV by the Impella increased aortic and intracoronary pressure, hyperemic flow velocity and CFVR, and decreased MR. The Impella-induced increase in coronary flow, probably results from both an increased perfusion pressure and a decreased LV volume-related intramyocardial resistance.
Remmelink
Maurice
M
Department of Cardiology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
Sjauw
Krischan D
KD
Henriques
José P S
JP
de Winter
Robbert J
RJ
Koch
Karel T
KT
van der Schaaf
René J
RJ
Vis
Marije M
MM
Tijssen
Jan G P
JG
Piek
Jan J
JJ
Baan
Jan
J
D000368:Aged; D015906:Angioplasty, Balloon, Coronary; D001011:Aorta / Q000503:physiopathology; D001783:Blood Flow Velocity; D001794:Blood Pressure; D006328:Cardiac Catheterization; D003324:Coronary Artery Disease / Q000150:complications / Q000503:physiopathology / Q000628:therapy*; D003326:Coronary Circulation; D005260:Female; D053805:Fractional Flow Reserve, Myocardial; D006353:Heart-Assist Devices; D006801:Humans; D006940:Hyperemia / Q000503:physiopathology; D008297:Male; D008833:Microcirculation / Q000503:physiopathology; D008875:Middle Aged; D012720:Severity of Illness Index; D013318:Stroke Volume; D014655:Vascular Resistance; D018487:Ventricular Dysfunction, Left / Q000209:etiology* / Q000503:physiopathology / Q000628:therapy