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Pulmonary Hypertension in a 45-YearOld Woman With Recurrent Deep
Venous Thromboses*
Jeana D. O’Brien, MD, FCCP; and Craig K. Reiss, MD
(CHEST 1999; 116:560 –563)
45-year-old African-American woman was reA ferred
for evaluation of pulmonary hypertension.
Five years before admission, the patient experienced
gradually progressive dyspnea on exertion with recent onset of fatigue, two- to three-pillow orthopnea,
paroxysmal nocturnal dyspnea, and lower extremity
edema. Evaluation before referral included pulmonary function studies showing normal spirometry,
mildly decreased total lung capacity and diffusion
capacity, and exercise desaturation to 84%. A transthoracic echocardiogram was reported to show normal left ventricular function, mild mitral and tricuspid regurgitation, and elevated mean pulmonary
arterial pressures.
There was also a history of atrial fibrillation,
recurrent deep venous thromboses, and a hypercoagulable state, although details of this diagnosis were
unavailable. Six years before admission, the patient
had undergone placement of a Greenfield vena caval
filter. Past surgeries include an abdominal hysterectomy and lumbar spinal disk surgery 7 years before
admission.
She was a disabled former automotive spray
painter who did not use tobacco, alcohol or other
drugs. Current medications included furosemide,
warfarin, captopril, digoxin, and nitrates.
162.6 cm in height. She was afebrile with a heart rate
of 106 beats per minute, a respiratory rate of 26
breaths per minute, and BP of 140/80 mm Hg. Room
air O2 saturation was 94%.
Head, eye, ear, nose, and throat examination was
normal. The neck was supple, short, and without
lymphadenopathy. Cardiac examination showed jugular venous distension to the mandible, a prominent
apical impulse, and right ventricular heave with
pulmonary artery (PA) tap. The rhythm was irregularly irregular with a prominently wide split S2, and a
grade 3/6 blowing holosystolic murmur across the
precordium, which accentuated with inspiration. Examination of the lungs revealed minimal crackles in
Physical Examination
The physical examination revealed an alert, obese
woman in no distress. She weighed 118.2 kg and was
*From the Division of Pulmonary and Critical Care Medicine,
Division of Cardiology, Barnes-Jewish Hospital, Washington
University School of Medicine, St. Louis, MO.
Manuscript received December 23, 1998; revision accepted
March 15, 1999.
Correspondence to: Jeana D. O’Brien, MD, FCCP, Division of
Pulmonary and Critical Care, Scott and White Clinic, 2401 S 31st
St, Temple, TX 76508; e-mail: [email protected]
Figure 1. Chest radiograph.
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Pulmonary and Critical Care Pearls
the bases with vesicular breath sounds. Soft bruits
were heard over all lung fields. The abdomen was
obese and nontender without hepatosplenomegaly.
There was 21 pitting edema to the knees with
chronic stasis changes bilaterally, which was warm to
the touch. There was no cyanosis or clubbing. There
were no skin lesions noted, and neurologic examination was grossly intact.
Laboratory and Additional Studies
The WBC count was 4.9/mL; hemoglobin level, 14.1
g/dL; hematocrit, 41%; platelet count, 153,000/mL;
chemistry profile was normal except for bilirubin, 6.3
mg/dL, lactate dehydrogenase, 353 U/L, aspartate
transaminase, 55 U/L, and alkaline phosphatase, 317
U/L. The results of arterial blood gas tests performed at
rest with room air were the following: pH, 7.46; Pco2,
35 mm Hg; Po2, 78 mm Hg; prothrombin time, 17.1 s.
ECG showed atrial fibrillation, right ventricular hypertrophy, and right axis deviation. Chest radiograph
showed moderate cardiomegaly with pulmonary vascular and azygos vein prominence, mild volume overload,
and enlargement of the PAs (Fig 1). Echocardiogram
showed right atrial and right ventricular enlargement
with paradoxical septal motion, moderate tricuspid
regurgitation, no aortic or mitral valve disease, elevated
mean PA pressures, and normal left ventricular function.
What is the most likely diagnosis in this patient?
CHEST / 116 / 2 / AUGUST, 1999
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561
Diagnosis: Abdominal arteriovenous fistula
This patient presented with dyspnea on exertion,
orthopnea, paroxysmal nocturnal dyspnea, and lower
extremity edema, as well as an echocardiography
report of pulmonary hypertension. Many symptoms
of pulmonary hypertension overlap with those of
congestive heart failure, particularly right-sided
heart failure. Careful attention to the physical examination may help narrow the differential and direct
further evaluation. Along with the estimation of PA
pressures, echocardiography is useful to evaluate left
ventricular function and look for valvular or pericardial disease.
In addition to symptoms and echocardiographic
findings of pulmonary hypertension, our patient had
physical examination characteristics of a high output
state, uncharacteristic for most forms of pulmonary
hypertension. This included warm hands and feet,
brisk carotid upstrokes, and a “prominent” apical
impulse. Patients with severe pulmonary hypertension commonly have cold hands and feet. She also
had pulmonary bruits typically reported in association with chronic thromboembolic pulmonary hypertension. These bruits have been attributed to flow
across “branch stenoses” at sites of embolic narrowing, but may also be caused by high flow in pulmonary arterioles.
The differential diagnosis significantly narrows
when high output failure is suggested by the clinical
examination, primarily to systemic arteriovenous
(AV) shunts, hyperthyroidism, multiple myeloma,
beri-beri, and severe anemia. Although our patient’s
history suggested thromboembolic disease, increased
attention to the examination findings of a high
cardiac output state and notation of the abdominal
bruit would have directed earlier evaluation toward
abdominal arteriovenous fistula (AVF). A detailed
history inclusive of surgeries, vascular procedures
(including central lines), and penetrating trauma, as
well as careful examination for scars and bruits, may
further guide attention toward an acquired AV communication.
When systemic AV shunts are present, the clinical
and hemodynamic aspects may vary depending on
whether these shunts are congenital or acquired, or
depending on their physical characteristics. Causes
for acquired AV communications include the abovementioned causes (penetrating trauma, surgery),
Paget’s disease, chronic liver disorders, and myelofibrosis. In 1965, Holman described experimental and
clinical evidence suggesting small to moderate fistulae with rigid borders typically remain stationary in
size with no demonstrable deleterious effects on the
heart or circulation. In contrast, fistulae with a
distensible rim yield to the high arterial pressure and
develop progressive dilatation, leading in time to
cardiac dilatation. Depending on the size of the
fistula and transfer of blood from a high- to a
low-pressure system, this sequence of events may
take years or may occur rapidly.
Although AVFs have long been known to potentially cause high output failure, marked pulmonary
hypertension is rare. Although the pulmonary pressures increase to some extent because of increased
left ventricular end-diastolic pressure from chronic
volume overload, it has been suggested by Braunwald that, in some patients, there is additionally a
reactive pulmonary hypertension because of the
increased pulmonary blood flow. This was postulated
years ago by Trell as being caused by precapillary
vascular obstruction but has not been pathologically
documented.
Our patient did not report onset of dyspnea until 2
years after the disk surgery with onset of symptoms
of right heart failure even later. Although likely
related to the small initial fistula size, in the setting of
AVF, the heart has latent capacity to accept greater
and greater volumes of blood without developing
failure because of the lowered peripheral vascular
resistance of the fistula circuit and concomitant
hypertrophy. In a vicious cycle, there is also compensation for the blood diverted through the fistula
circuit by gradual expansion of the total blood volume because of activation of the renin-angiotensinaldosterone axis and effects of arginine-vasopressin.
With fistula closure, the heart size regresses, and
blood volume decreases to normal.
Treatment for most acquired AVF is surgical
closure, which typically results in rapid improvement
in symptoms and regression of pulmonary hypertension and cardiomegaly. The occurrence of AVF with
pulmonary hypertension after spinal disk surgery has
been reported with a review of the world literature
by Machado-Atias and coworkers. This diagnosis was
not initially considered in our patient because of the
history of venous thrombosis. Increased attention to
the clues provided on the physical examination may
have further directed her initial evaluation.
Our patient was admitted with a diagnosis of
pulmonary hypertension likely caused by recurrent
thromboembolic disease. A ventilation/perfusion
scan was performed, which was interpreted as a low
likelihood ratio for pulmonary emboli with no segmental perfusion defects. Given the high clinical
suspicion for pulmonary embolic disease, a pulmonary angiogram was performed. The right and left
PAs were large, as were the major second- and
third-order branch vessels, without evidence of
thromboemboli. PA pressure measurements were
the followng: right PA, 74/34 mm Hg (mean, 52 mm
Hg); and left PA, 80/28 mm Hg (mean, 62 mm Hg).
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Pulmonary and Critical Care Pearls
Table 1—Evaluation of Pulmonary Hypertension
Site
Oxyhemoglobin, %
Pressures, mm Hg
Low inferior vena cava
High inferior vena cava
Superior vena cava
Right atrium
Right ventricle
Right PA
Left PA
Pulmonary wedge
90
89
75
80
82
82
82
—
—
—
30
75/24
68/47
30
After diuresis, the patient underwent a right heart
catheterization with an oxyhemoglobin assessment as
additional evaluation of pulmonary hypertension
(Table 1). Thermodilution cardiac output was 15
L/min; BP, 124/77 mm Hg; heart rate, 81 beats per
minute; arterial blood pH, 7.49; arterial Pco2, 41
mm Hg; arterial Po2, 69 mm Hg; arterial O2 content,
19.8 vol%; mixed venous O2 content, 17.8 vol%; and
O2 saturation, 78%.
These oxyhemoglobin measurements suggested a
shunt involving the lower inferior vena cava. Additional careful auscultation of the patient’s abdomen
detected a bruit near the midline of the lower
abdomen. An aortogram was performed, which demonstrated a large AVF between the right iliac vein
and aorta. The fistula was believed to be caused by
the patient’s lumbar disk surgery performed 7 years
earlier, and did not appear related to the inferior
vena cava filter. Surgical repair was performed.
The patient experienced rapid improvement in
symptoms within the first weeks to months postoperatively. Two years later, she underwent cardiac catheterization to evaluate chest pain after a dual-isotope scan
yielded abnormal findings. This revealed normal epicardial arteries and a normal left ventriculogram. Hemodynamic measurements were as follows: right atrial
pressure, 4 mm Hg; right ventricular pressure, 40/7
mm Hg; PA pressure, 40/20 mm Hg; pulmonary
capillary wedge pressure, 15 mm Hg; left ventricular
end-diastolic pressure, 18 mm Hg; cardiac output, 8.1
L/min; and cardiac index, 3.7 L/min/mL. She has had
continued clinical improvement since her initial presentation, with her only complaints being intermittent
atypical chest pain.
Clinical Pearls
1. Careful physical examination can direct the
diagnostic evaluation of patients with symptoms of pulmonary hypertension or congestive
heart failure.
2. Right heart catheterization with oxyhemoglobin
assessment should be considered in any patient
with pulmonary hypertension without apparent
cause.
3. Although commonly asymptomatic, systemic
AV shunts may present as pulmonary hypertension or high output failure. Symptoms are
typically reversible with surgical repair of the
shunt.
4. Spinal disk surgery is a well-established although infrequent risk factor for the occurrence
of AVF.
Suggested Readings
Braunwald E. In: Braunwald E, ed. Heart disease: a textbook of
cardiovascular medicine. 5th ed. Philadelphia, PA: WB Saunders, 1997; 460
Holman E. Abnormal arteriovenous communications: great variability of effects with particular reference to delayed development of cardiac failure. Circulation 1965; 32:1001–1009
Machado-Atias I, Fornes O, Gonzalez-Bello R, et al. Iliac
arteriovenous fistula due to spinal disk surgery. Tex Heart Inst
J 1993; 20:60 – 65
Moser KM, Auger WR, Fedullo PF, et al. Chronic thromboembolic pulmonary hypertension: clinical picture and surgical
treatment. Eur Respir J 1992; 5:334 –342
Trell E. Pulmonary hypertension in shunt lesions. Klin Wochenschr 1974; 52:1043–1052
Wood P. Pulmonary hypertension. Br Med Bull 1952; 8:348 –353
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