This document discusses lung and heart-lung transplantation. It covers the pathophysiology, effects on exercise response, exercise testing and training recommendations post-transplant. Key points include reduced aerobic capacity post-transplant due to factors like denervation, immunosuppressants, and deconditioning. Exercise has been shown to improve outcomes by increasing VO2peak and mitigating medication side effects. Ongoing management of transplant patients focuses on immunosuppression and preventing/treating complications.

2. Lung and heart-lung transplantation
Overview of the pathophysiology
Since the first human lung transplant was attempted in june 1963 by Hardy and colleagues. Over
8.000 lung and heart-lung transplant procedures have been performed. One-year actuarial
survival now approaches 75 to 80% after lung transplantation , which compares favorably with the
sobering 18 days as witnessed for the initially reported case. Since the introduction during the
early 1980s of cyclosporine , a calcineurin inhibitor-type of immunosuppressive medication , lung
and heart-lung transplantation have became clinically successful endeavors for myriad end-stage
cardiopulmonary diseases.
The physiologic responses observed posttransplant , however reflect not the attributes of the
allograft lung but rather an admixture of responses as determined by the nature of each patients
native lung disease, state of conditioning , and type of transplant procedure ( e.g., single or
bilateral lung , heart-lung transplant).furthermore ,potential adverse effects of
immunosuppressive drugs may affect the physiologic responses to exercise after transplantation .
a thorough discussion regarding the clinical management of these complicated patients is beyond
the scope of this text ; however ,familiarity with their complex exercise physiology should aid
exercise prescription and successful rehabilitation.
The type of surgical procedure is determined in light of several key factors:the native
cardiopulmonary disease, recipient age,and scarcity of donor organs.in the united states ,
approximately 74.000 patients currently await solid organ transplantion , while nearly 4.000
specifically require either lung or heart –lung organ donation.therefore , single lung transplant
(SLT) procedures are frequently pursued for older recipients who suffer from either the spectrum
of diseases associated with interstitial pulmonary fibrosis or emphysema.conditions associated
with significant pulmonary vascular disease (e.g., primary pulmonary hypertension ,
eisenmengers complex , sarcoidosis ) may be approached with either single or bilateral lung
transplantation but generally do not require an en bloc heart-lung transplant except in situations
involving complex congenital heart disease. Pulmonary diseases characterized by chronic airway
suppuration ( e.g., cystic fibrosis, bronchiectasis)require bilateral lung transplantation to thereby
eliminate both native lungs that pose a serious risk for posttransplant infection during
immunosuppression.
The conventional surgical approach to either single or bilateral lung transplantation entails
anastomosis of proximal mainstem bronchus (or bronchi,for bilateral),pulmonary artery , and
reestablishing pulmonary venous effluent by means of anastomosis of a left atrial “cuff”.SLT is
accomplished via a traditional posterolateral thoracotomy incision , while an extensive transverse
bilateral anterior thoracosternotomy ( clam shell incision ) is utilized for bilateral grafts. Heart-lung
transplantion involves the en bloc implantantion of bilateral lungs and heart via a median
sternotomy incision. During these surgical procedures, most centers do not perform
revascularization of the bronchial arterial circulationwhile patients are similarly rendered “

3. extrinsically denervated” from autonomic influences and are devoid of normal pulmonary
lymphatic drainage. The physiologic responses observed after transplant, therefore, may be
significantly affected by these fundamental physiologic differences.
Effects on the exercise response
Clinical investigations have suggested the following alterations in function that may impact
theexercice response observed posttransplantation:
Bronchial hyperresponsiveness to either inhaled methacholine, hypertonic saline
aerosol, or exercise has been demonstrated in a significant number of lung
transplant recipients . hyperresponsiveness may relate to either extrinsic
cholinergic pulmonary denervation or airway inflammation such as during
allograft rejection or infection .
Abnormal mucociliary clearance may relate to a physical impediment imposed by
the bronchial anastomosis. Additionally,studies have suggested bronchial mucosal
abnormalities characterized by altered epithelium, decreased ciliary beat
frequency , and alteration in mucous theology.
Cardiac sympathetic denervation after combined heart-lung transplantation,
similar to isolated orthotopic heart transplantation ,can reduce the archieved
maximum exercise heart rate, peak oxygen consumption (VO2peak), peak oxygen
pulse, and lactate threshold.cardiacreinnervation later occurs in a proportion of
such patients and is associated with improved chronotropic and inotropic cardiac
responses and enhanced oxygen delivery to exercising skeletal muscles.
Altered pulmonary vascular permeability may occur soon after lung
transplantation and relate to “ischemia reperfusion” graft injury or, later in their
clinical course.during episodes of rejection and associated perivascular
inflamamation . physiologic consequences of an increased pulmonary vascular
permeability and interstitial edema may include a decline in spirometric indices,
increased wasted ventilation, and increased ventilation –perfusion inequality and
gas exchange .
Altered respiratory pattern(i.e.,disproportionate increase in tidal volume at a
reduced respiratory rate).consistent with the absence of vagal –mediated inflation
inhibition (hering-breuer reflex),has been detected after combined heart-lung and
bilateral lung transplantation .stable heart-lung recipients with normal graft
function.however.manifiest an appropriate response of ventilation to exercise or
progressive hypercapnia.furthermore. pulmonary denervation does not impede
the normal tachypneic response to either an increased elastic impedance or
intrinsic pulmonary restriction . by contrast, the hypercapnic ventilation response
may appear blunted relatively soon after lung transplantation when specifically
performed for end-stage hypercapnic chronic obstructive `pulmonary disease. But

4. subsequently returns toward normal.further. the detection of inspiratory resistive
loads appears normal after combined heart-lung transplantation .despite the
absence of pulmonary afferent innervations.
Abnormal pulmonary function tests are frequently observed after both hear-lung
and isolated pulmonary transplantation .heart- lung transplant recipients often
have a mild restrictive ventilator defect that may relate to volumetric constraints
of the recipient chest cavity and thoracic musculature. The elastic behavior or
pressurevolume relationships after uncomplicated lung transplantation appear
relatively normal.values for vital capacity and maximum expiratory flow rates are
expectedlyless after single(approximately 60% of predicted normal value) versus
bilateral or heart-lung transplantation.
Effects of exercise training
Despite attaining higher spirometric values after single or bilateral lung or
combined heart-lung transplantation,cardiopulmonary exercise studies have
demonstrated the following:
Values forVO2peak (approximately 45-55% of predicted)and maximum
work rate in these recipients arre reduced.
An abnormally reduced “threshold”forlactate,ventilation ,and standard
bicarbonate are observed in association with reduction in maximal
tolerable exercise capacity, although this cannot be ascribed to factors
such as cardiac dysfunction,anemia,or limitations imposed by pulmonary
vasculature or lung mechanics.
Quadriceps muscle biopsies and 31P-magnetic resonance spectroscopy
after clinical lung transplantation have suggested a decrease in proportion
of type I fibers and reduced skeletal muscle oxidative capacity and
reduced intracellular pH. No difference has been detected in the activities
of glycolytic enzymes, while transplant recipients demonstrate a higher
reliance on glycolyticnon-oxidative metabolism . therefore,alteration in
fiber proportion and reduced mitochondrial activity may indeed
contributed to the exercise limitation witnessed after lung
transplantation.
Immunosuppressant medications may potentially contribute to an
alteration in exercise physiology.systemic glucocorticoids have well-
described adverse effects on peripheral skeletal muscle and are commonly
administered to patients suffering from a spectrum of pulmonary diseases
prior to transplant.as well as in combination therapies
posttransplantation.

5. Glucocorticoids can induce a selective atrophy of type II
fibers:however,because these are the major source for lactate production
in exercising skeletal muscle, one would not expect corticosteroids to
cause inordinate intracellular acidosis.calcineurin inhibitor-type
immunosuppressive medications (e.g.,cyclosporine or tacrolimus) have
been shown to inhibit skeletal muscle mitochondrial respiration in vitro
and diminish endurance exercise time in rats.the mechanism involved is
not entirely clear but may relate to diminished mitochondrial calcium
efflux with subsequent mitochondrial dysfunction.no impact on fiber
size has yet been attributed to cyclosporine.although reduction in
capillarity of limb musculature may further contribute to the reduction in
aerobic capacity.
Lung and heart-lung transplantation: exercise testing
methods measures Endpoints comments
aerobic 12 lead ECG,HR serious •Atrial rrhythmias
cycle dysrhytmias common early
(ramp protocol BP >2mm ST segment posttransplant .
10-15 watts/min; Depression
staged protocol Respired gas T-wveinversión •Heart-lung
25 watts/3min analysis with transplant may be
stage) associated with
Significant ST
Treadmill cardiac
Blood lactate change
( 1 MET/3min denervation.
stage)
RPE,dyspnea SBP>250mmHg or
scales DBP>115mmHg •Lung transplant
may be associated
(0-10) with absent hering-
Pulse oximetry Máximum breuer reflex.
or arterial PO2. ventilation
VO2peak Very reduced
transitional
Lactate / thresholds for
ventiltory lactate and
HCO3.
Threshold
Endurance distance Note •Useful measure
6min walk vitals,dyspnea in assessing
Index,SaO2 at rest stops pretransplant
severity of illness
and posttransplant
progress.
Strength • Peak torque • Decreased

6. Isokinetic/isotoni • Maximun muscle mass/
c number of reps force related to
corticosteroids.
Flexibility •Hip,hamstring,lower • Post-
Sit and stretch Back flexibility thoracotomy pain
may restrict
flexibility.
Neuromuscular Tremors
Gait analysis and
Balance possible
myopathy
with
calcineurin
inhibitors.
• Decreased
visual acuity due to
cataracts or
diabetes.
Functional • Perform tests if
Sit to stand Clinically indicated
Stair climbing
lifting
MEDICATIONS
Many of the following medications are used for either immunosuppression or as prophylaxis to
thereby prevent potential posttransplant complications:
Calcineurin-inhibitor immunosuppressive
medications(e.g.,cyclosporine,tacrolimus),
TORinhibitor (e.g., rapamycin ),
Antimetabolities(e.g.,azathioprine,methotrexate,mycophenolatemofetil.
Loop and thiazide diuretics: may contribute to electrolyte abnormalities and
muscle weakness.
Antihypertensive medications(e.g., beta blockers, ACE inhibitors,calcium-channel
blockers).
Antibiotics( e.g., quinolone-type(e.g., ciprofloxacin), trimethoprim
sulfamethoxazole,antiviral(e.g.,ganciclovir sodium, acyclovir).
MEDICATIONS (CONTINUED)

7. HMG CoA reductase inhibitor medications(e.g.,”statins”) for hyperlipidemia
posttransplant: may cause muscle pain or severe muscle injury with potential
kidney failure.
Calcineurin inhibitors: may cause tremor , neuropathy or myopathy, electrolyte
abnormalities ( decreased magnesium and increased potassium), renal tubular
metabolic acidosis,or kidney failure.
TOR inhibitors:may cause bleeding tendency (decreased patelets) and
hyperlipidemia.
Beta blockers: may reduce heart rate response to exercise.
Calcium-channel blockers: may cause leg swelling or hypotension.
Quinoloneantibiotics:may cause tendinitis and tendon rupture .
Antiviral medications: may have associated neurotoxicity.
Many medications may cause anemia or leucopenia. The spectrum of adverse
medication effects may impact exercise capacity or muscle function.
The physiologic different in exercise physiology and aerobic capacity
notwithstanding.one preliminary study after lung transplantation has
demonstrated significant benefitsfrom formal exercise conditioning.after a six-
week program whereupon training intensity ranged from 30 to 60& of maximum
heart rate reserve.improvements were observed in minute ventilation,cardiac
reserve, and VO2peak.congruent with these findings,recent studies of similarly
immunosuppressed heart transplant recipients have also highlighted the benefits
of structured exercise training.therefore to mitigate the potential adverse effects
of immunosuppressive medications and the frequent preexistent state of
deconditioning. Structured exercise rehabilitation program may offer significant
clinical advantages.
Management and medications
Pulmonary transplantation offers a renewed sense of hope and quality of life for enumerable
patients with end-stage cardiopulmonary diseases. Nevertheless,the required chronic
immunosuppressive medications represent a double-edged sword after transplant. Although
decreasing the incidence of acute graft rejection.such medications may heighten the risk of
developing opportunistic infection, malignancy ,osteoporosis,hypertension,diabetes mellitus , and
associated toxicity. The exercise physiologist should be cognizant of these potential complications
and maintain vigilance accordingly.notable complications for the posttransplant patient may
include the following:

8. Acute allograft rejection and dysfunction are often heralded by increseaded
subjective sensation of dyspnea, reduction in spirometricsunction, and gas
exchange. Expeditious evaluation of the patient for possible transbronchoscopic
biopsy and therapy is imperative.
Pneumonia,although often related to typical community-acquired viral or bacterial
infections, may be attributed to opportunistic or atypical atypical pathogens
caused by chronic immunosuppressive medications.routine patient vaccination
with polyvalent pneumococcal and annual influenza vaccines are recommended.
Systemic hypertension is often related to adverse effects of glucocorticoids and
calcineurin inhibitor-type medications.patients often will require
antihypertensive medications with frequent dosage adjustments. However
significant elevation in blood pressure may indicate a toxic blood level range for
either cyclosporine or tacrolimus versus potential worsening renal function
related to these medications.
Osteoporosis , related to both systemic glucocorticoids and calcineurin inhibitor-
type immunosuppressants, poses a significant risk for vertebral and hip fracture
after transplantation, newer prophylactic strategies for osteoporosis include
calcium supplementation,hormonal replacement therapy,bisphosphonates,as well
as exercise,strength,and balance training.
Chronic anemia is usually related to suppression of the bone marrow by
immunosuppressive medications. However, various viral infections
(e.g.,parvovirus B19, herpesvirus)may sometimes be responsible.severe
reductions in hemoglobin concentration may affect the patients peak exercise
tolerance and ventilator threshold.
Bronchiolitis obliterans syndrome(BOS)or chronic graft rejection represents the
achillesheel of lung transplantation and may affect two –thirds of recipients by
five years.progressive small airway fibrosis and obliteration result in an
inexorable decay in lung function over time that frequently is refractory to
augmented immunosuppressive therapies.recurrent respiratory tract infections
and abnormalities of larger airways (i.e.,bronchiectasis ) frequently ensue.
Abnormalities of glucose tolerance and metabolism.related to immunosuppressive
medications,may complicated the clinical course of these patients.excessive
weight gain and potential diabetic complications may be favorably impacted by
regular exercise and nutritional counseling.

9. Lung and heart-lung transplantation: exercise programming
Modes goals Intensity/frequency/durati Time to goal
on
Aerobic Increase VO2peak and THR 60-80% of peak HR Variable,3-12
Large muscle endurance RPE 11- mo (depending
activities Increase lactate and 13/20(comfortable pace) on
(walking, ventilatory thresholds Monitor dyspnea posttransplant
cycling, Decreased sensitivity to 1-2 sessions /day medical/surgical
swimming) dyspnea 3-7 days/wk complications)
Develop more efficient 20-30 min/session
breathing patterns (shorter intermittent
Restore ADLs exercise sessions may be
necessary initially)
Emphasize duration over
intensity
Strength Increase maximal Low resistance, high reps Variable,3-
Free weights number of reps 2-3 days/wk 12mo
Isokinetic Increase isokinetic
/Isotonic torque/work
machines Increased lean body
mass
Flexibility Increase ROM Daily
Stretching
Tai chi
Neuromuscular Improve gait and Daily
Walking and balance
balance Decrease muscle
exercises weakness and
Breathing myopathy
exercises
Functional Restore ADLs Daily
Activity- Return to work
specific Improve quality of life
exercises Restore sexuality
medications Special considerations
See exercise RPEanddyspnea are the preferred methods of
testing table monitoring intensity. Many clients are unable to
achieve a training HR yetdemosntrate physiologic
improvement.
Musculoskeletal complaints, postsurgical chest wall
pain, and osteoporosis are common posttransplant
complications
Myopathy involving respiratory and peripheral
muscles may be related to calcineurin inhibitors and
corticosteroid medications.severe muscle pain may

10. indicate a serious complication of “statin” type lipid-
lowering medications.
“bronchial hyperresponsiveness”posttransplant may
contribute to exercise-related bronchospasms and
dyspnea
Clients usually respond to exercise optimally in mid
to late morning, due to adverse
effects(e.g.,nausea,fatigue)of morning medication
schedules
Avoid extremes in ambient temperature and
humidity caused by frequent use of antihypertensive
and diuretic medications
Supplemental O2 may be required either early
posttransplant or subsequent to graft complications
New or worsening SaO2 responses to exercise may
indicate organ rejection or infection and should be
communicated to the transplant team
Anxiety,depression,and/or fear are commom effects
of dyspnea or medications such as corticosteroids
Bronchial anastomosis complications may significantly affect clinical outcomes after lung
transplantation. Fortunately,neither dehiscence nor bronchovascular fistula complications
are presebtlycommom.however development of bronchial anastomotic stricture or
stenosis usually caused by exuberant scar tissue formation may both impair spirometric
function and the normal”mucociliary escalator”.posttransplant inflammation involving
airway cartilage rings may contribute to bronchomalacia, whereupon dynamic airway
collapse may limit expiratory flow rates. Potential remedies may include endobronchial
laserphotoresection of granulation tissue and/ or deployment of a bronchial stent to
thereby maintain the bronchial lumen.furthermore, localized infections of the
anastomosis(e.g.,fungal) may require therapy with systemic or inhaled aerosol
antibiotics.bronchoscopic assessment is generally required to establish a definitive
diagnosis and ,thus, direct the appropriate therapies.
Recommendations for exercise testing
The primary objectives for exercise testing are two-fold(1) to assess the severity of
exercise impairment prior to organ transplant or determine progression of disease and
urgency for transplantation and (2)to characterized exercise limitations
posttransplantation .pretransplant assessment of VO2max or 6 min walk distance
correlate with severity of illness for cystic fibrosis .for example,and the associated risk of
death while awaiting transplantation.posttransplant testing may be valuable in
determining whether exercise limitation is related to graft dysfunction,occult cardiac
disease , peripheral muscle weakness. Or a persistent state of deconditioning .

11. During either era,pre-or posttransplantation,the principal objectives for exercise testing
are similar (also see the lung and heart-lung transplantation: exercise testing table on page
119):
Assess severity of disease or progression
Assess maximal physical work capacity and state of aerobic fitness
Observed cardiorespiratory and metabolic responses to exercise
Observe oxyhemoglobin saturation during exercise
Provide a basis for prescribing exercise within safe limits and
Assess changes in fitness and cardiorespiratory responses to exercise that occur
with disease progression or medical /surgical interventions.
Recommendations for exercise programming
The principal goals of exercise training, both pre-and posttransplantation,are to improve aerobic
fitness and alleviate the sense of dyspnea.exercise prescriptions should be tailored to the type of
native kung disease, level of patient fitness , and posttransplant allograft spirometric function(see
the lung and heart-lung transplantation: exercise programming table on page 12).pretransplant
patients with pulmonary arterial hypertension,for example, may be predisposed to development
of right ventricular ischemia , arterial oxygen desaturation,and syncope during exertion.exercise
of moderate intensity ( 60-80% of peak heart rate) should be targeted for approximately 20 to 30
min. beta blockers received posttransplant may limit exercise heart rate response; therefore.
Assessment of perceived exertion may be preferable.patients should be encouraged to adopt
healhy lifestyle modifications that incorporate aerobic activities.balanced diet, and maintenance
of appropriate body weight.
Special consideration
All patients after organ transplantion and certain patients prior to transplant require chronic
immunosuppression,which poses and increased risk for serious infection. Isolation of such patients
from the general population in rehabilitation programs is generally not warranted. Although one
should be cognizant of the potential risks for transmission of respiratory pathogens from other
clients. Maintaining cleanliness of all exercise equipment and patient avoidance of potential ill
contacts during these sessions should be emphasized. Potential for impaired glucose tolerance or
systemic hypertension as an adverse effect of immunosuppressive medications should be
monitored during exercise and related to the referring physician. significant deterioration in
exercise tolerance or arterial oxygen saturation from prior baseline values may represent a
harbinger of allograft rejection, cytomegalovirus, or other posttransplant opportunistic infections.
such data may be of crucial importance to the organ transplant team in determining the need for
expeditious clinical evaluation and bronchoscopic lung biopsy. The clinical value in maintaining
excellent lines of communication with the transplant team is of paramount importance.

12. LUNG TRANSPLANTATION
CASE STUDY
A 45-year old woman underwent bilateral sequential lung transplantation three years ago for
interstitial pulmonary fibrosis complicated by severe secondary pulmonary hypertension with
right-sided heart failure. She initially improved quite dramatically with respect to both spirometric
lung function and exercise tolerance, and went home (to Kuwait) approximately three months
posttransplant on standard triple-drug immunosuppression ( i.e.,cyclosporine,
mycophenolatemofetil, and prednisone). She returned for reevaluation complaining of progressive
shortness of breath and recurrent respiratory tract infections with methicillin-resistant
staphylococcus aureus and pseudomonas aeruginosa. She also complained of severe low back pain
after sustaining a “slip and fall” injury.
S: “ icant breathe again, and my back hurts”
O: middle-aged woman, on oxygen,breathless and extremely fatigable with minimal exertion
Breath sounds:bilateral basilar crackles and musical inspiratory and expiratory rhoncho
Thoracolumbar spine:midly tender to palpation,with decreased ROM for flexion and extension
Neurologic examination: normal
Pulse oximetry: 95% arterial oxygen saturation on 3l/min O2 via nasal prongs
Chest Xrays:bibasilar scarring and probable dilated and thickened larger airways or bronchiectasis
Spirometry: significant decreases in FVC and FEV; severe obstructive ventilator defect
Spine X rays: multiple compression fractures of T7,T9 and L1
Spine MRI scan: no evidence of malignancy
A:
1. BOS, or chronic graft rejection
2. Recurrent respiratory tract infection caused by bronchiectasis and recent exacerbation
3. Osteoporosis with multiple vertebral compression fractures
4. Severe exercise intolerance

13. P:
1. Intravenous antibiotic treatment of current respiratory infection is needed
2. Prescribe aerosolized antibiotic prophylaxis for chronic bronchiectasis
3. Treat osteoporosis pharmacologically
4. Additional immunosuppression to prevent further loss of lung function from chronic
rejection(e.g, tacrolimus and methotrexate) is necessary
5. Prescribe outpatient pulmonary rehabilitation
Exercise program
Goals:
1. Improve functional capacity to increase and maintain ADLs
2. Alleviate dyspnea;improve strength and balance/coordination
3. Pulse oximetry during exercise to determine supplemental oxygen requirements
mode frequency duration intensity progression
aerobic 3days/wk 20-30min/session THR(110 Progress as tolerated
contractions/min) over 6-wk program
RPE 12/20
Strength ( all 2days/wk 2 sets of<_ 12 To fatigue Add resistance until
major muscle reps 12 reps achieves
groups) fatigue
Flexibility Daily 20-60s/stretch Hold below Maintain
discomfort
threshold
Neuromuscular Daily Individualized as As tolerated Maintain
(walk drills, needed
breathing
exercises)
Functional ( Daily Individualized as As tolerated Gradual over 3-12
activity-specific needed mo
exercises)
Warm-up/ cool- Before and after 10 min RPE<10/20
down each session

14. Suggested readings
Brings,MS M Fournier D.J ross and M.I. lewis 1998. Cellular adaptations of skeletal muscles to
cyclosporine.Journal of applied physiology 84:1967-75.
GaroneS and D.J ross 1999 bronchiolitis obliterans syndrome: rewiev of our know ledge and
treatment strategies.current opinion in organ transplantation 4:254-63
Grossman.R.F and J.R maurer 1990 pulmonary considerations intransplantation.clinics in chest
medicine 11:2
Hokanson, J.F . J.G mercier and G.A brooks.1995 cyclosporine a decreases rat skeletal muscle
mitochondrial respiration in vitro.american journal of respiratory and critical care medicine
151:1848-51
Iber.C.Psimon J.B skatrud et al 1995 the breuer-hering reflex in humans: effects of pulmonary
denervation and hypocapnia.american journal of respiratory and critical care medicine 152:217-24
Joint statement of the American society for transplant physicians( ASTP)/American thoracic society
(ATS)/European respiratory society (ERS)/international society for heart and lung transplantation
(ISHLT).1998 international guidelines for the selection of lung transplant candidates.american
journal of respiratory and critical care medicine 158:339-39
Miyoshi S. E.P trulock H-J schaefers et al 1990 cardiopulmonary exercise testing after single and
double lung transplantation .chest 97:1130-36
Ross D.J P.F waters. A .mohsenifar et al 1993. Hemodynamic responses to exercise after lung
transplantation .chest 103:46-53
Schwaiblmair M. W von scheidt.P uberfuhr et al 1999. Functional significance of cardiac
reinnervation in heart transplant recipients.journal of heart and lung transplantation 18(9):838-45
Stiebellehner L. M quittan A end et al. 1998. Aerobic endurance training program improves
exercise performance in lung transplant recipients.chest 113(4):906-12.