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October 2001
Volume 65 |
Number 10
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| Anesthesia
for Mechanical Replacement Hearts |
Kenneth A. Thielmeier,
M.D.
N. Martin Giesecke, M.D
The surgical treatment of end-stage heart
disease has included the implantation of mechanical replacement
hearts for almost as long as orthotopic transplantation has been
an option. Development of an artificial heart began in the 1950s
with Kolff and Akutsu, who successfully performed the first animal
implantation at the Cleveland Clinic in 1957. 1
In 1969, only two years after Barnard performed the first human
heart transplant in South Africa, Cooley and his colleagues at
The Texas Heart® Institute successfully utilized a total artificial
heart as a bridge to transplant in a patient who was unweanable
from cardiopulmonary bypass. 2 He repeated this
use in 1981 with a second successful bridge to transplant. 3
| “ …if the current FDA trial for the use of
totally implantable replacement hearts proceeds successfully,
more widespread utilization likely will occur. The involvement
of the anesthesiologist in the implantation team is critical
for the success of this important technology.” |
In 1982, DeVries and associates at the
University of Utah utilized for the first time the total artificial
heart as a destination therapy. The Jarvik-7 (now known as the
CardioWest TAH) maintained the patient for 112 days.4 DeVries’
work continued at the Humana Heart Institute in Louisville, Kentucky,
with three subsequent permanent implantations. 5
Complications associated with these patients led the Food and
Drug Administration (FDA) to stop further permanent implantations
of this device. The CardioWest TAH (CardioWest, Inc., Tucson,
Arizona), however, has been used successfully as a bridge to transplant
at a limited number of centers since that time. 6
The AbioCorTM Implantable Replacement Heart
(ABIOMED, Inc. Danvers, Massachusetts) is the only device currently
available for implantation as a destination therapy and is limited
to an FDA trial at this time. The first placement of this totally
implantable replacement heart occurred on July 2, 2001, at the
Rudd Heart & Lung Center of Jewish Hospital in Louisville,
Kentucky. Other centers involved in this preliminary clinical
trial include the Texas Heart Institute, Brigham and Women’s
Hospital, Massachusetts General Hospital, University of California-Los
Angeles Medical Center and the Hannemann University Hospital.
This trial opens a new chapter in the perioperative
management of patients receiving permanent, implantable replacement
hearts. The role of cardiovascular anesthesiologists in the implantation,
postoperative care and subsequent anesthetics of these patients
will be substantial. Though currently limited to just these few
centers, this totally implantable replacement heart may represent
one solution to the supply/demand discrepancy that exists for
refractory cardiac failure patients today.
Patients meeting the eligibility requirements
to enter this trial represent a particularly ill subset of the
population usually cared for by the cardiovascular anesthesiologist.
These patients will present with biventricular failure and by
criteria will have a 30-day mortality of at least 70 percent.
Renal, hepatic and pulmonary insufficiency are all presenting
features.Coagulopathies associated with hepatic and renal insufficiency,
as well as anticoagulants and antiplatelet agents, will likely
effect perioperative bleeding. Many patients, especially those
with ischemic cardiomyopathies and decompensated congenital heart
disease, will likely be repeat sternotomies with the associated
bleeding and dysrhythmia risks. Monitoring and infusion access
may pose a particular challenge in these patients who are likely
to have had multiple arterial and central venous lines in the
past. Many will present with indwelling central venous lines that
may hinder the placement of more appropriate access. Inotropes
as well as intra-aortic balloon pumps or other ventricular assist
devices are likely to be present before implantation. 7
Monitoring considerations include standard
monitors utilized for most cardiac cases as well as others such
as inferior venacava pressure (obstruction risk) and left-atrial
pressure monitoring (placed at implantation). Transesophageal
echocardiography, with all its recognized utility, also provides
information regarding flow across both atrial ventricular valves
of the device as well as outflow information in both the aortic
and pulmonary conduits. 7 Of particular interest
is the evaluation of pulmonary venous flow, which may be affected
by the positioning of the device itself.8 Neurologic monitoring
may have a role in those patients who may be at particular risk
for embolic complications, especially gaseous. 7
Premedications, induction agents and maintenance
anesthetics must be guided by the preoperative level of impairment
of each patient. After implantation, some medications may have
different pharmacodynamic profiles as their prebypass myocardial
depressant effects become unimportant (e.g., sodium thiopental).
The same is true of inotropic agents whose effects after implantation
are limited to preload and afterload changes. Some vasoactive
drugs such as nitroglycerine may become poor choices as they may
impair necessary preload and provide no advantages such as coronary
vasodilitation. Pharmacologic interventions aimed at renal and
neurologic preservation also may be appropriate in this patient
population. 7
In conclusion, if the current FDA trial
for the use of totally implantable replacement hearts proceeds
successfully, more widespread utilization likely will occur. The
involvement of the anesthesiologist in the implantation team is
critical for the success of this important technology.
References:
1. Akutsu T, Kolff WJ. Permanent substitutes for
valves and hearts. Trans Am Soc Artif Int Organs. 1958; 4:230.
2. Cooley DA, Liotta D, Hallman GL, et al. First
human implantation of cardiac prosthesis for staged total replacement
of the heart. Trans Am Soc Artif Int Organs. 1969; 15:252.
3. Cooley DA, Akutsa T, Norman JC, et al. Total
artificial heart in two-staged cardiac transplantation. Cardiovascular
Diseases, Bulletin of the Texas Heart Institute. 1981; 8:305.
4. DeVries WC, Anderson JL, Joyce LD, et al. Clinical
use of the total artificial heart. N Engl J Med. 1984; 310:273.
5. DeVries WC. The permanent artificial heart:
Four case reports. JAMA. 1988; 259:849-859.
6. Copeland JG, Smith RG, Arabia FA, et al. The
CardioWest total artificial heart as a bridge transportation.
Semin Thorac Cardiovasc Surg. 2000; 12:238-242.
7. Thielmeier KA, Pank JR, Dowling RD, et al.
Anesthetic and perioperative considerations in patients undergoing
placement of totally implantable replacement hearts. In press:
Seminars in Cardiothoracic & Vascular Anesthesia. November
2001.
8. Thielmeier KA. Unpublished data.
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Kenneth A. Thielmeier,
M.D., is Partner, Medical Center Anesthesiologists, PSC.,
Director of Cardiovascular Anesthesiology, Rudd Heart &
Lung Center/Jewish Hospital, Louisville, Kentucky, and Clinical
Assistant Professor of Anesthesiology, University of Louisville
School of Medicine, Louisville, Kentucky. |
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Martin N. Giesecke,
M.D., is Staff Anesthesiologist, Texas Heart Institute/St.
Luke’s Episcopal Hospital, Houston, Texas, and Clinical
Assistant Professor, University of Texas Health Science Center
Medical School, Houston, Texas. |
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