Right ventricular performance and contractile reserve in patients with severe heart failure. Assessment by pressure-area relations and association with outcome.
BACKGROUND
Right ventricular (RV) performance appears to be important in patients with severe heart failure. Although clinical assessments of RV function previously have been limited to load-dependent ejection phase indices, a new method has been developed using the relatively load-insensitive concepts of pressure-volume relations with automated echocardiographic measures of RV cross-sectional area as a surrogate for volume.


RESULTS
Sixteen patients with New York Heart Association functional class IV heart failure and group mean left ventricular ejection fraction of 20 +/- 5% were studied. RV pressure-area loops were recorded on-line from echocardiographic measures of RV area and high-fidelity pressure during transient inferior, vena caval balloon occlusions. RV contractile reserve was assessed as its functional response to an increase in dobutamine from 5.7 +/- 4.1 to 13.1 +/- 4.7 micrograms/kg per minute. Complete data sets were available in 13 patients. Group mean RV end-systolic elastance (E'es) and maximal elastance (E'max) increased with augmented dobutamine infusion (2.9 +/- 1.5 to 5.5 +/- 3.3 mm Hg/cm2 and 3.3 +/- 1.6 to 6.4 +/- 3.9 mm Hg/cm2, respectively; P < .01 versus baseline), although individual responses were variable. During a 30-day follow-up, 9 patients remained unstable, requiring continuous intravenous inotropic therapy; 6 of these had profound deterioration requiring mechanical circulatory support. The remaining 4 patients had a comparatively good short-term outcome with clinical stability. A 100% increase in RV E'es or E'max was associated with a good short-term outcome (P < .05).


CONCLUSIONS
RV performance can be assessed by pressure-area relations in patients with heart failure. RV contractile reserve in response to increases in dobutamine was associated with a good short-term outcome and may be of prognostic value in patients with severe heart failure.
Gorcsan
J
J
Division of Cardiology, University of Pittsburgh Medical Center, PA 15213-2582, USA. gorcsan@al.isd.upmc.edu
Murali
S
S
Counihan
P J
PJ
Mandarino
W A
WA
Kormos
R L
RL
D000328:Adult; D002302:Cardiac Output; D002316:Cardiotonic Agents / Q000627:therapeutic use; D004280:Dobutamine; D004452:Echocardiography; D005260:Female; D005500:Follow-Up Studies; D006333:Heart Failure / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000503:physiopathology*; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction / Q000187:drug effects; D011237:Predictive Value of Tests; D011651:Pulmonary Artery / Q000503:physiopathology; D011669:Pulmonary Wedge Pressure; D013318:Stroke Volume / Q000187:drug effects; D013997:Time Factors; D016896:Treatment Outcome; D016278:Ventricular Function, Right / Q000187:drug effects / Q000502:physiology*
D002316:Cardiotonic Agents; D004280:Dobutamine