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JACC: HEART FAILURE
VOL. 4, NO. 3, 2016
ª 2016 BY THE AMERICAN COLLEGE OF CARDIOLOGY FOUNDATION
PUBLISHED BY ELSEVIER
ISSN 2213-1779/$36.00
http://dx.doi.org/10.1016/j.jchf.2015.12.012
EDITORIAL COMMENT
A Machine Without an Owner’s Manual*
Joseph G. Rogers, MD,a,b Adam D. DeVore, MDa,b
C
ontemporary growth in the use of left ven-
select a single constant speed, ignoring the obvious
tricular assist devices (LVADs) to support pa-
changes in physiological demand that occur during
tients
is
daily life. Most providers determine optimal speed
remarkable. In the United States alone, more than
using echocardiographic guidance with the patient
2,400 LVADs were implanted in adults in 2014
recumbent and at rest, selecting a speed that mini-
compared with 459 in 2008 (1). Although periopera-
mizes patient symptoms without excessively unload-
tive survival is comparable to that for routine cardiac
ing the left ventricle. Alternatively, a ramp study may
with
advanced
heart
failure
surgical procedures, 50% of LVAD patients have died
be utilized in which final settings are determined by
within 4 years of implantation (1). Long-term man-
careful study of the impact of graduated increases in
agement of LVAD patients remains enigmatic and
device speed on patient symptoms, vital signs, ven-
program specific, lacks a robust evidence base, and
tricular geometry, and valve function (4).
could reasonably be postulated to contribute importantly to the observed morbidity and mortality. The
SEE PAGE 208
most recent guideline on outpatient LVAD manage-
In this issue of JACC: Heart Failure, Uriel et al. (5)
ment cites only 3 of 69 (4.3%) recommendations as
extend their previous work on the noninvasive ramp
being Level of Evidence A (2) compared with 22%
study and describe an approach to determining
high-level recommendations in the most recent
optimal LVAD speed by integrating hemodynamic
American College of Cardiology/American Heart As-
and echocardiographic parameters. The authors per-
sociation heart failure guideline (3). Questions per-
formed ramp studies with simultaneous right-sided
taining to common clinical conundrums such as the
heart catheterization and echocardiography in 35
most appropriate dose of antiplatelet agents, the
stable outpatients thought to be well supported on
best strategy for the management of right-sided heart
their LVAD based on their reported medical history,
failure, and the optimal treatment for refractory
physical examination, and laboratory test results
mucosal bleeding remain eminence based. There is
(Figure 1). The goal was to define the LVAD speed
an urgent need to develop evidence that guides
associated with the most desirable hemodynamic
patient and device management for normal LVAD
and echocardiographic parameters: central venous
physiology and complications for this increasingly
pressure <12 mm Hg, pulmonary capillary wedge
common and expensive medical intervention.
pressure <18 mm Hg, intermittent aortic valve
LVAD speed is the one parameter that can be
opening, and minimized mitral regurgitation.
adjusted to change the level of support provided by
There was a striking discordance between clinical
contemporary LVADs. Current technology for the 2
assessment of optimal hemodynamics and those found
commercially available devices allows providers to
in the laboratory, with fewer than 50% of this cohort
meeting the hemodynamic goals at baseline. After
*Editorials published in JACC: Heart Failure reflect the views of the au-
guided speed adjustment, the proportion of patients
thors and do not necessarily represent the views of JACC: Heart Failure or
with desirable hemodynamic profiles increased from
the American College of Cardiology.
43% to 56%, with nearly one-third of the patients
From the aDepartment of Medicine, Duke University School of Medicine,
requiring an important speed change as a result of the
Durham, North Carolina; and the bDuke Clinical Research Institute, Duke
ramp test. An increase in LVAD speed resulted in
University School of Medicine, Durham, North Carolina. Dr. DeVore has
patient-specific increases in cardiac output and re-
received research funding from Amgen, the American Heart Association,
Maquet, Novartis, and Thoratec. Dr. Rogers has reported that he has no
ductions in pulmonary capillary wedge pressure
relationships relevant to the contents of this paper to disclose.
without an acute change in the central venous pressure.
Rogers and DeVore
JACC: HEART FAILURE VOL. 4, NO. 3, 2016
MARCH 2016:218–9
A Machine Without an Owner’s Manual
Although this study provides important new
knowledge that may allow better patient and device
F I G U R E 1 Protocol Summary
management, important limitations must be acknowledged, the most obvious being the lack of clear
linkage between speed optimization and outcomes.
There are almost no clinical trial data that confirm a
clear relationship between hemodynamics and outcomes in non–device-treated heart failure patients,
which raises the possibility that this approach may not
favorably impact symptoms, functional capacity,
quality of life, or LVAD-related morbidity. In addition,
broad application of invasive ramp studies in LVAD
patients has inherent risk that must be weighed against
the value of the information provided. The ventricular
assist device community needs to be certain that there
is tangible patient benefit beyond a modest hemodynamic benefit and more photogenic hearts. Finally, the
durability of these hemodynamic changes and the
potential that ramp testing should be repeated with
some frequency must be addressed.
Summary of the combined hemodynamic and echocardiographic ramp test protocol. Patients
with either a Heart Mate II (HMII)( Thoratec, Pleasanton, California) or HeartWare ventricular
device (HVAD) (HeartWare International, Framingham, Massachusetts) were included in the
study (*). CVP ¼ central venous pressure; echo ¼ echocardiography; INR ¼ international
normalized ratio; LVAD ¼ left ventricular assist device; LVEDD ¼ left ventricular end-diastolic
The number of patients in the United States eligible
for advanced heart failure therapies is estimated to be
dimension; max ¼ maximum; PCWP ¼ pulmonary capillary wedge pressure; PTT ¼ partial
thromboplastin time.
between 250,000 and 300,000 (6), and the number of
patients living in the community with LVAD support
proper design, INTERMACS could be used as the data
continues to grow. The establishment of an evidence
repository and analytical center for such a network
base for the long-term management of patients with
and would promote synergies and broad application
LVADs is essential. We continue to operate in silos of
of successful interventions.
care that rely heavily on INTERMACS (Interagency
This past weekend, many of us may have worked
Registry for Mechanically Assisted Circulatory Sup-
diligently to assemble a piece of furniture, repair a car
port) (7) to describe trends in LVAD use; however,
engine, or fix a computer glitch. Few would attempt
INTERMACS may not be well suited for much of the
such a feat without detailed instruction, sage counsel,
heavy lifting required to improve VAD outcomes.
proper tools, and an instruction manual. These tools,
Creation of an LVAD research network structured
based on experience and experimentation, ensure
similarly to the National Institutes of Health–funded
success for “do-it-yourselfers.” We should not have a
Heart Failure Research Network and the Cardiac
lower expectation for medical devices.
Surgery Network would facilitate the development of
foundational knowledge. These networks consist
REPRINT REQUESTS AND CORRESPONDENCE: Dr.
of high-volume centers committed to clinical trials
Adam D. DeVore, Duke Clinical Research Institute, 2400
with a well-defined infrastructure that allows rapid
Pratt Street, NP-7047B, Durham, North Carolina 27705.
implementation and execution of small studies. With
E-mail: [email protected].
REFERENCES
1. Kirklin JK, Naftel DC, Pagani FD, et al.
Seventh INTERMACS annual report: 15,000 patients and counting. J Heart Lung Transplant 2015;
34:1495–504.
Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. J Am Coll
Cardiol 2013;62:e147–239.
6. Miller LW. Left ventricular assist devices are
underutilized. Circulation 2011;123:1552–8, discussion
1558.
2. Feldman D, Pamboukian SV, Teuteberg JJ, et al.
The 2013 International Society for Heart and Lung
Transplantation guidelines for mechanical circulatory support: executive summary. J Heart Lung
Transplant 2013;32:121–46.
4. Uriel N, Morrison KA, Garan AR, et al. Development of a novel echocardiography ramp test for
speed optimization and diagnosis of device
7. Interagency Registry for Mechanically Assisted
Circulatory Support. INTERMACS website. Available at: https://www.uab.edu/medicine/intermacs/.
thrombosis in continuous-flow left ventricular
assist devices: the Columbia ramp study. J Am Coll
Cardiol 2012;60:1764–75.
Accessed November 10, 2015.
3. Yancy CW, Jessup M, Boskurt B, et al. 2013
ACCF/AHA guideline for the management of heart
failure: a report of the American College of
5. Uriel N, Sayer G, Addetia K, et al. Hemodynamic
ramp tests in patients with left ventricular assist
devices. J Am Coll Cardiol HF 2016;4:208–17.
KEY WORDS advanced heart failure,
left ventricular assist devices, mechanical
circulatory support
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