Use of Cardiopulmonary Exercise Testing
With Hemodynamic Monitoring
in the Prognostic Assessment of
Ambulatory Patients With Chronic Heart Failure
Marco Metra, MD,* Pompilio Faggiano, MD,† Antonio D’Aloia, MD,* Savina Nodari, MD,*
Anna Gualeni, MD,* Domenica Raccagni, MD,* Livio Dei Cas, MD*
Brescia, Italy
OBJECTIVES We studied whether direct assessment of the hemodynamic response to exercise could
improve the prognostic evaluation of patients with heart failure (HF) and identify those in
whom the main cause of the reduced functional capacity is related to extracardiac factors.
BACKGROUND Peak exercise oxygen consumption (VO
2
) is one of the main prognostic variables in patients
with HF, but it is influenced also by many extracardiac factors.
METHODS Bicycle cardiopulmonary exercise testing with hemodynamic monitoring was performed, in
addition to clinical evaluation and radionuclide ventriculography, in 219 consecutive patients
with chronic HF (left ventricular ejection fraction, 22 Ϯ 7%; peak VO
2
, 14.2 Ϯ
4.4 ml/kg/min).
RESULTS During a follow-up of 19 Ϯ 25 months, 32 patients died and 6 underwent urgent
transplantation with a 71% cumulative major event-free 2-year survival. Peak exercise stroke
work index (SWI) was the most powerful prognostic variable selected by Cox multivariate
analysis, followed by serum sodium and left ventricular ejection fraction, for one-year survival,
and peak VO
2
and serum sodium for two-year survival. Two-year survival was 54% in the
patients with peak exercise SWI Յ30 g⅐m/m
2
versus 91% in those with a SWI Ͼ30 g⅐m/m
2
(p Ͻ 0.0001). A significant percentage of patients (41%) had a normal cardiac output
response to exercise with an excellent two-year survival (87% vs. 58% in the others) despite
a relatively low peak VO
2
(15.1 Ϯ 4.7 ml/kg/min).
CONCLUSIONS Direct assessment of exercise hemodynamics in patients with HF provides additive indepen-
dent prognostic information, compared to traditional noninvasive data. (J Am Coll Cardiol
1999;33:943–50) © 1999 by the American College of Cardiology
The progressive increase in the number of patients listed for
heart transplantation despite the limited availability of heart
donors has prompted efforts to redefine criteria for selection
of candidates for heart transplantation (1–3). Peak oxygen
consumption (VO
2
) has emerged as one of the most
important prognostic variables (4 –10), and its reduction is a
major criterion of selection for heart transplantation
(3,6,10,11).
Peak VO
2
is highly dependent on the hemodynamic
response to exercise (4,12–14) and, therefore, measures the
cardiovascular reserve of the patient. However, it may also
be influenced by other factors. It has been observed that, in
a significant proportion of patients with heart failure (HF),
the main cause of functional limitation may reside in an
abnormality of skeletal muscle metabolism with earlier lactic
acidosis despite a normal peripheral blood flow (15,16).
However, as these patients may present a significant impair-
ment of resting left ventricular function and functional
capacity, they should be identified through an additional
procedure. Accordingly, some studies have suggested that
the direct assessment of the hemodynamic response to
exercise may improve the prognostic evaluation of patients
with HF (17–19), but these data have not been confirmed
by other investigators (20,21).
In our study, we assessed the prognostic value of the
hemodynamic variables measured at peak exercise, com-
pared with the resting hemodynamic data and variables
obtained by noninvasive exams, in a large group of ambu-
latory patients with chronic HF.
From the *Cattedra di Cardiologia, Universita´ di Brescia and †Divisione di
Cardiologia, Ospedale Fatebenefratelli, Brescia, Italy. This study was partially
supported with a fund from the target project FATMA (protocol n.91.00137.41) of
the National Council of Research, Rome, Italy and with a fund from the CARIPLO
foundation of the “Centro per lo studio del trattamento dello scompenso cardiaco.”
Manuscript received October 9, 1997; revised manuscript received October 23,
1998, accepted December 11, 1998.
Journal of the American College of Cardiology Vol. 33, No. 4, 1999
© 1999 by the American College of Cardiology ISSN 0735-1097/99/$20.00
Published by Elsevier Science Inc. PII S0735-1097(98)00672-X