Progressive improvement in cardiac performance with continuous aortic flow augmentation (aortic flow therapy) in patients hospitalized with severe heart failure: results of the Multicenter Trial of the Orqis Medical Cancion System for the Enhanced Treatment of Heart Failure Unresponsive to Medical Therapy (MOMENTUM).
BACKGROUND
Previous studies indicate that superimposing incremental continuous flow on pulsatile aortic flow (aortic flow therapy, AFT) yields an increase in cardiac output. This study examined whether improvement in this hemodynamic index is independent of changes in loading conditions and represents an improvement in cardiac performance.


METHODS
The Multi-center Trial of Orqis Medical Cancion System for Enhanced Treatment of Heart Failure (HF) Unresponsive to Medical Therapy (MOMENTUM) was a randomized trial comparing AFT plus medical therapy (n = 109) vs medical therapy alone (n = 59) in patients hospitalized with HF inadequately responsive to therapy. Entry required reduced left ventricular ejection fraction (LVEF) and cardiac index, elevated pulmonary capillary wedge pressure (PCWP), and impaired renal function or high diuretic requirement despite intravenous inotrope or vasodilator treatment. AFT was achieved for up to 96 hours using an arterial-to-arterial circuit (flow up to 1.5 liters/min). Changes in cardiac performance were assessed using the relationship between cardiac index (CI) or stroke work (SW = stroke volume x [Mean blood pressure - PCWP] x 0.00133, kg.cm) and PCWP.


RESULTS
In the control group, a decrease in PCWP was accompanied by a decline in SW from 3.2 +/- 1.4 at baseline to 2.7 +/- 0.9 kg.cm at 4 days. AFT increased SW (from 3.0 +/- 1.6 at baseline to 3.3 +/- 1.7 kg.cm at 4 days; p < 0.0001) and decreased PCWP. An upward-leftward shift occurred in the SW vs PCWP relationship in the AFT group.


CONCLUSIONS
AFT resulted in a progressive upward-leftward shift in the SW-PCWP relation compared with the control group, demonstrating improvement in cardiac performance independent of load-related effects.
Zile
Michael R
MR
RHJ Department of Veterans Affairs Medical Center Charleston, Medical University of South Carolina, South Carolina 29425, USA. zilem@musc.edu
Colombo
Paolo C
PC
Mehra
Mandeep
M
Greenberg
Barry
B
Brown
Scott
S
Konstam
Marvin A
MA
D000328:Adult; D000368:Aged; D001794:Blood Pressure / Q000502:physiology; D002302:Cardiac Output / Q000502:physiology; D005260:Female; D006321:Heart / Q000503:physiopathology*; D006333:Heart Failure / Q000503:physiopathology / Q000601:surgery*; D006339:Heart Rate / Q000502:physiology; D006353:Heart-Assist Devices; D006801:Humans; D008297:Male; D008875:Middle Aged; D011669:Pulmonary Wedge Pressure / Q000502:physiology; D013318:Stroke Volume / Q000502:physiology; D016896:Treatment Outcome