Improvement in Exercise Performance after Pulmonary Arteriovenous Malformation Embolization

Treatment of the pancreatitis includes resting the gastrointestinal tract, pain medication and parenteral hyperalimentation when indicated. Definitive therapy for the pseudocyst c'Onsists of surgical internal drainage by a cystogastrostomy or cysto-jejunostomy.13.'7 Draining the abdominal pseudocyst empties the mediastinal extension. Approximately 70 percent of pseudocysts are successfully treated in this manner and there is a much lower recurrence rate c'Ompared with the older technique of external drainage. In summary, the lessons learned from our patient are as follows: (1) large mediastinal pseudocysts may not be readily apparent on the chest radiograph, (2) amylase levels should be obtained in all patients with chronic pleural effusions of unknown etioloh'Y, (3) a chest CAT scan is a sensitive tool to detect a mediastinal pseudocyst, and (4) in some patients, conservative treatment and parenteral hyperalimentation may be associated with resolution of the pseudocyst. REFERENCES

RK. l(,rres WE. Colvin RS. McoClees EC, Baron MG. Thoracic findin~s in ~astrointestinal patholo~y. Radiol Clin North Amer 1984; 22:563-89 Rodan BA. Gocke TM, Bean WJ. Fen~ TS. Mediastinal pancreatic pseudocyst. Southern Med J 1983; 76:262-63 Jaffe BM. Ferguson TB, Holtz S, Shields JB. Mediastinal pancreatic pseudocysts. Am J Surg 1972; 204:600-06 Edell SL. Good LI. Mediastinal pancreatic pseudocyst. Am J Gastrolenteroll982; 71:78-82 Weinfeld A. Kaplan JO. Mediastinal pancreatic pseudocyst. Gastrointest Radio11979; 4:343-47 McoCarthy S. Bookhinder M. Blumenfeld J. Kelly LJ. Keohane MF. Medinastinal pseudocyst. J Clin Gastroenterol 1982; 4:45Ged~;U1das-McoClees

2 3 4 5 6

Improvement in Exercise Performance after Pulmonary Arteriovenous Malformation Embolization* Guy W Soo Hoo, M.D.; Peter). Julien, M.D.; Harvey V. Brown, M.D., F.C.C.P.; lIncl Michael). Belman, M.D .. FC.C.P.

Balloon or coil embolization has become established therapy for multiple PAVMs. We were able to evaluate a 32year-old woman with multiple PAVMs characterized by significant orthodeoxia, intrapulmonary shunt, dyspnea and limited exercise tolerance before and after balloon and coil embolization. After embolization of three of her largest PAVMs, repeat evaluation revealed improvement in her symptoms, orthodeoxia and intrapulmonary shunt. She was able to exercise two additional work rates with a sustained improvement in oxygenation, a decrease in the P(A-a)O. difference and higher maximum oxygen consumption. These studies provide objective evidence of persistent improvement in function and endurance at rest and during exercise after embolization, (Chest 1990; 97:1016-18)

=

=

PAVM pulmonary arteriovenous malformation; P(A-a)O, alveolar-arterial oxygen pressure difference; PA pulmonary artery; Dsb single-breath diffusing capacity for carbon monoxide.

=

=

48

7 Banks PA, Mclellan PA, GerJ:of SG, Splaine EF, Lintz RM, Brown NO. Mediastinal pancreatk pseudocyst. Di~estive Dis Sci 1984; 29:664-68 R Kirchl\('r SG, Heller RM, Smith CW Pancreatic pseudocyst of the mediastinum. Dia~ RadioI1977; 123:37-42 with cervical 9 Mosimann F. Lopez J. Media.stinal enlar~ement swellin~. Chest 1983; 83:261-62 10 Ball JB. Clark RA. CT of mediastinal pancreatic fluid c'OlIections. Computerized Radio( 1982; 6:295-300 Il Shivakumar 0, Gour~outis GO, Shah RM. Posterior mediastinal mass lesion. Chest 1984; 85:683-84 12 Winton TL, Birchard R, Nguyen KT, Taguchi K. Esophageal ohstrnction secondary to a mediastinal pancreatic pseudocyst. Can J Sur~ 1986; 29:376-77 13 Matzin~er

FRK, Chia-Sin~

H. Yee AC, Gray RR. Pancreatic

pseudocysts drained through a percutaneous transgastric approach: further experience. Interventional Radiology 1988; 167:431-34 14 Mullins RJ, Malan~oni MA. Ber~amini TM, Casey JM, Richardof pancreatic pseuson JD. Controversies in the mana~ement docysts. Am J

Sur~

1988; 155:165-72

15 lIunt JL, Eph~rave K. Emer~ency sur~ery psendocysts. South Med J 1987; 80:462-65

for pancreatic

16 Johnston RH, Owensby Le, Vargas GM, Garcia-Rinaldi R. Pancreatic pseudocysts of the mediastinum. Ann Thorac Sur~ 1986; 41:210-12 I7 Semelka RC, Greenberg HM. Percutaneous drainage of an

infected mediastinal pseudocyst. J Can Assoc Radiol 1987; 38:54-55 1016

pnlmonary an~io~ram demonstratin~ two (ar~e Fu:ulIF. l. Ri~ht PAVMs (white armws) subsequently o(:c1uded and several small PAVMs (black arrows). A left pulmonary an~io~ram (not shown) demonstrated a lar~e PAVM which was also occluded. ImprOllement in Exercise Perfonnance (500 Hoo

et al)

Table I-Pulmonary Function Testing, Arterial Blood Gas Values and Exercise Measurements before and after Embolization of PAVM, Before (4/87) Pulmonary function testing FEV. (L), % predicted FVC (L), % predicted FEV/FVC(%) TLC (L), % predicted Dsb (mVmin/mm Hg), % predicted Hemoglobin (gm/dL) Arterial blood gases Room ai....supine/upright pH P02 (mm Hg) Pco2 (mm Hg) HCOJ (mEqIL) P(A-a)02 difference (mm H~) Breathing 100% O 2 Pa02 (mm Hg) Qs/QT (% shunt) Exercise Heart rate, max (beats per minute), % of max predicted VE, rest/max exercise (Umin BTPS) Vo2 (mVmin) PaO~Z, rest/75 W (mm Hg) P(A-a)02 difference, rest/75 W (mm Hg)

M

ultiple PAVMs pose a difficult management problem. They are associated with significant morbidity (cerebrovascular accidents, brain abscess, endocarditis, etc) and mortality.I.2 Surgical resection can be definitive but is of limited utility in patients with multiple lesions. 3 Balloon and coil embolization has become an acceptable and successful method of management."-6 However, with multiple PAVMs, the potential for unembolized lesions to dilate and physiologic abnormalities to worsen exists, especially during periods of increased blood flow (eg, during exercise). The following report documents improvements in gas exchange and exercise capacity after successful balloon and coil embolization.

4.03, 121 5.28,135 76 7.15, 120 36.4, 114 15.2

4.12, 5.46, 7S 7.68, 25.2, 14.9

7.47n.47 62/49 30131 22/22 49/61

7.4417.47 70/6.'3

129

*From the Pulmonary Division, Department of Medicine and Department of Radiology, Cedars-Sinai Medical Center, Los Angeles.

124 140

276 27

129 SO

:3:31:31 22/23

:3.5/47

33

136 (72) 15.7/52.3 1097 49/51 62/70

ISO (79) 11.3164.3 1309

57/54

54/6.5

eventually stopped \\'orkin~ as a hair dresser hecause she could not tolerate the hours of standin~ that her joh required. Evaluation in April 1987 included full pulrnonary function testing, a shunt study standard 0Iethods 7 .,. (Tahle 1). There and an exercise study usin~ were no other symptoms or physkal findin~s referahle to her PAVMs. Because of progressive sylnptolns, she undern'ent halloon and coil embolization of the three largest PAV~ts in Septelnher 1987. Approximately 12 additional small PAVMs were visualized hy angiography but not embolized (Fig 1). HenuKlynamk evaluation

.-e

4/87 0-0 10/87

.--....-.........

60

CASE REPORT

A 32-year-old woman with a 15 pack-year smoking history was evaluated for dyspnea. Her history is notable for syncope at age six, with a normal cerebral angiogram and ventriculogram upon evaluation. She had two uneventful pregnancies at 23 and 25 years old. She was well until 1982 when at the age of 26, she was noted to have a nodular lesion on a routine chest roentgenogram prior to elective varicose vein surgery. Chest tomography suggested the presence of PAVMs. She reported minimal dyspnea only during heavy exertion and was unavailable for follow-up. Three years later, she underwent evaluation because of chest pressure, palpitations and dyspnea on heavy exertion. A cardiac echocardiogram demonstrated mitral valve prolapse and nonsustained ventricular tachycardia was seen on ambulatory Holter monitoring. Chest <,'omputed being 2 cm in tomography revealed multiple PAVMs, the lar~est size. Her cardiac symptoms were controlled with disopyramide. She felt well and missed several follow-up appointments. Two years later, she began to note increasing fatigue and decreased exercise tolerance with dyspnea on exertion after one Right of stairs. She

After (10/87)

....... '

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.......

40

100

300

500

700

900

.-- ..........--.'

1100 1300

,,--- ..........

100

300

500

700

. - . 4/87 0-0 10/87

900

1100 1300

OXYGEN CONSUMPTION (002) (milmin) FIClTRE 2. Improveolent in PaO:! (olm H~) and P(A-a)():z (0101 IIg) during exercise hefore (solid circ/l's) and after (open circles) elnh()lization of PAVMs. CHEST / 97 / 4 / APRIL, 1990

1017

showed a PA pressure of 14/5 mm H~ and a mean PA pressure of 10 mm H~. Improvement in oxy~enation with a decrease in P(A-a)Oz difference \\'as noted immediately after the procedure. In October 1987, she underwent repeat pulmonary function and (Table 1 and Fi~ 2). She reported improvement in exercise testin~ her symptoms although she still noted mild dyspnea upon prolonged standin~ and effi>rt. Examination at testing was remarkable only for Lalx>ratory data was notable for a a mid-systolic click and clubbin~. helno~lohin value of 14.9 gm/dl. Her only medication was disopyramide.

the preembolization Pa02 • Thus, her remaining PAVMs must not dilate to achieve preembolization shunt levels with exercise. In follow-up 18 months after embolization, she continues to feel well without any decrement in functional activities. ACKNOWLEDGMENTS: The writers thank William Shark, M.D., for allowing us to evaluate his patient.

REFERENCES

DISCUSSION

Many of the clinical features of PAVMs are illustrated by this patient. She was asymptomatic until young adulthood when she developed dyspnea on exertion, platypnea and clubbing. There was no evidence of or a family history of a more generalized process (hereditary hemorrhagic telangiectasia) or systemic disorder (cirrhosis) that may have been associated with PAVMs. Prior to embolization, she had decreased exercise capacity, a large right-to-Ieft shunt and significant orthodeoxia. One t'Onsideration in her management involved the possibility of worsening intrapulmonary shunt during periods of increased blood flow as might occur during exercise. Increases in intrapulmonary shunt have been reported during increases in lung volume and blood flow.Y'W Infrequently, clinically undetected PA\TMs enlarge to produce significant physiologic derangements after surgical resection.·1 Experience with coil or balloon embolization is limited, but self-reported improvement has persisted in follow-up.4-6 No objective evaluation of postembolization exercise tolerance previously has been reported. One month after embolization, she reported near total resolution of her symptoms. This correlated with improvement in her objective parameters. Her hypoxemia and orthodeoxia improved. The shunt fraction (Qs/Qr) decreased from 33 to 27 percent. Of note, the Dsb declined about 30 percent. This difference probably exceeds expected test-totest variation and suggests further reduction in functional capillary volume. Embolization of normal pulmonary vasculature as well as PAVMs could account for this decrement and may be a limiting cOlnplication if future embolizations are required. This would effectively increase dead space which would explain the preserved lung volumes. Improvement was noted during exercise. The maximum VO:2 increased 19 percent from 1,097 to 1,309 mVmin. She exercised two additional work rates (75 vs 105 W). The maximum heart rate increased 10 percent from 136 to 150 beats per minute. Her resting VE declined 27 percent from 15.7 to 11.3 Umin, while her maximum VE during exercise increased 23 percent from 52.3 to 64.3 Umin. There was sustained improvement in oxygenation with a decrease in the P(A-a)02 difference during exercise although this improvement diminished at higher levels of work. This report provides objective evidence of improvement in function and endurance at rest and during exercise after successful embolization of multiple PAVMs. However, a significant (27 percent) shunt persists and there is undoubtedly increased flow through her remaining PAVMs during exercise as evidenced by O 2 desaturation and an increase in the P(A-a)02 difference at the highest levels of exercise. Her Pa0:2 after embolization at maximum exercise is better than 1018

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5

6

7

8

9 10

Burke CM, Safai C, Nelson D~ Ramn TA. Pulmonaryarteriovenous malformations: a critical update. Am Rev Respir Dis 1986; 134:334-39 Dines DE, Arms RA, Bernatz PE, Gomes MR. Pulmonary arteriovenous fistulas. Mayo Clin Proc 1974; 49:460-65 Prager RL, Laws KH, Bender HW Arteriovenous fistula of the lung. Ann Thorac Surg 1983; 36:231-39 Taylor BG, Cockeril EM, Manfredi F, Klatte EC. Therapeutic embolization of the pulmonary artery in pulmonary arteriovenous fistula. Am J Med 1978; 64:360-65 Terry PB, Barth KH, Kaufman SL, White RI. Balloon embolization for treatment of pulmonary arteriovenous fistulas. N Eng) J Med 1980; 302:1189-90 Terry PB, White RI, Barth KH, Kaufman SL, Mitchell SEa Pulmonary arteriovenous malformations: physiologic observations and results of therapeutic balloon embolization. N Engl J Med 1983; 308:1197-1200 Morris AH, Kanner RE, Crapo RO, Gardner RM. Clinical pulmonary function testing: a manual of uniform lalx>ratory procedures. 2nd ed. Salt Lake City: Intermountain Thoracic Society, 1984 Wasserman K, Hanson JE, Sue DY, Whipp BJ. Principle of exercise testing and interpretation. Philadelphia: Lea & Febiger, 1987 Huseby JS, Culver BH, Butler J. Pulmonary arteriovenous fistulas: increase in shunt at high lung volume. Am Rev Respir Dis 1977; 115:229-32 Smith G, Cheney F~ Winter PM. The effect of change in cardiac output on intrapulmonary shuntin~. Br J Anesth 1974; 46:337-42

A Case of Dirhythmic Breathing* Mart£n Escribano, M.D.; R. Melchor Iniguez, M.D.; Alfaro Abreu, M.D.; J Palomera Frade, M.D.; and R. Mart£nez Cruz, M.D.

~

J

We describe a case of dirhythmic breathing in a 6O-yearold man after neurosurgery. A large hemangioblastoma was removed from the cerebellum at the level of the fourth ventricle. The spirometric tracings showed two types of respiratory cycles: the rhythm A was stable with a short inspiratory time; sometimes a second type of respiratory cycle, B, was present or erratically coupled with the A rhythm. It had very small tidal volume and mean inspiratory How with phasic variations similar to those observed in Cheyne-Stokes breathing pattern. (Chest 1990; 97:1018-20)

S

pontaneous breathing patterns may give useful information about the regulation of breathing. 1.2 We describe a

*From the Section of Pneumology, Hospital 10 de Octubre, Madrid, Spain. A Case of Dirhythmic Breathing (Martin Escribano et all