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Rapid Visualization of Massive Pulmonary Emboli Utilizing Intravascular Ultrasound
Rapid Vi~ualization of Massive Pulmonary Emboli Utilizing Intravascular Ultrasound* Victor F. Tapson, M.D.; Charles]. Davidson, M.D.; Katherine B. Kisslo, R.D.M.S.; and RichardS. Stack, M.D.
Massive pulmonary embolism may result in rapid deterioration prlor to diagnostic and therapeutic intervention. Intravascular ultrasound imaging has been utilized previously to evaluate vascular abnormalities as well as normal human pulmonary arteries. We employed this technique to rapidly identify massive pulmonary emboli located in the main pulmonary arteries of two patients. The presence of
these emboli was confirmed with pulmonary arteriography. Intravascular ultrasound may be utilized to rapidly confirm the presence of large proximal pulmonary emboli. (Chest 1994; 105: 888-90)
Massive pulmonary embolism (PE) results in significant mortality. Rapid recognition and initiation of therapy is crucial. Intravascular ultrasound (IV US) imaging is a relatively new technique that has been utilized to characterize a variety of vascular disorders. 1•3 While invasive, this technique does not require contrast material, and studies of normal pulmonary arteries have been performed in humans. 4 We previously reported the use of IVUS to identify experimental PE in a canine model. 5 We now report the use of this technique to visualize massive emboli located in the main pulmonary arteries of two patients.
evaluation and treatment. Aventilation perfusion scan revealed absence of perfusion to the left lung with defects in the right lung as well. In view of previous falling episodes, a brain computed tomographic (CT) scan was performed revealing evidence of small vessel disease and lacunar infarcts. Because of unstable hemodynamics in the setting of a massive pulmonary embolus with an abnormal brain CT scan, direct infusion of lowdose thrombolytic therapy was contemplated. A 9-French sheath was inserted into the right femoral vein and pulmonary artery catheterization revealed the pulmonary artery pressure to be 34/ 14 (mean, 21) . A 4.8-French 20-MHz mechanically rotated IVUS catheter (Boston Scientific, Watertown, Mass) together with a portable ultrasound console (Diasonics, Milpitas, CaliO was utilized for IVUS imaging. With fluoroscopic guidance, a pulmonary artery guide catheter was advanced to the left main pulmonary artery and the IVUS catheter, rotating at 900 rpm, was advanced through the guide catheter into the left lower lobar pulmonary artery (Fig 1, left). As it was slowly withdrawn, a large embolus was visualized in the left main pulmonary artery (Fig 1, right). Images were recorded on 1.25-cm videotape. The embolus was confirmed by pulmonary arteriography (Fig 2) . The patient received 250,000 U of urokinase directly into the massive embolus with excellent results both clinically and arteriographically, and without bleeding complications.
CASE REPORTS CASF.
I
A 76-year-old white woman was admitted to the coronary care unit for further evaluation of severe dyspnea, hypotension, and atrial fibrillation . Her medical history was remarkable for anxiety and depression as well as difficulty with her balance resulting in at least one fall. On the morning of hospital admission, the patient developed severe dyspnea and was unable to stand. She denied chest pain, cough , fever, or chills. Examination in the emergency department revealed an irregular pulse at 120/min, a respiratory rate of 24/min, and a blood pressure of 65/40 mm Hg. The left lower extremity was warmer than the right and appeared somewhat firm on examination compared with the more flaccid right calf. Results of the remainder of the examination were normal. Electrocardiography revealed atrial fibrillation and a chest radiograph suggested a prominent right main pulmonary artery but was otherwise unremarkable. Arterial blood gas analysis on room air initially revealed a pH of7.45, Po 2 of 54, and Pco 2 of 32. The patient received intravenous normal saline solution and the blood pressure improved to 130/60 mm Hg. She was transferred to the coronary care unit for further *From the Division of Pulmonary and Critical Care Medicine (Dr. Tapson) and the Division of Cardiology (Drs. Davidson and Stack and Ms. Kisslo), Duke University Medical Center, Durham , NC . Manuscript received February II, 1993; revision accepted June 30 Reprint requests: Dr. Tapson, Box jJJ75, Duke University Medical Center, Durham , NC 27710
888
IVUS =intravascular ultrasound; PE bolism
CASF.
=pulmonary
em-
2
A 66-year-old white man presented to the emergency department for further evaluation of dyspnea and presyncope. The systolic blood pressure was 90 mm Hg and an arterial blood gas analysis revealed a pH of7.46, Po2 of 42, and Pco2 of28. Ventilation perfusion scanning revealed almost complete lack of perfusion to the left lung with a smaller defect on the right. He was placed on a regimen of heparin and dopamine and the blood pressure improved to approximately 100/60 mm Hg. Because of hemodynamic instability, thrombolytic therapy was contemplated and the patient was taken to the interventional cardiac catheterization laboratory. Right heart catheterization revealed mean right atrial and pulmonary artery pressures of 16 and 70/35 (mean, 45) respectively. Large defects in the main pulmonary artery as well as in the more distal branches were demonstrated by pulmonary arteriography. An IVUS catheter was then advanced through the right heart guide catheter and over a 0.035-cm guidewire into the proximal left main pulmonary artery. Intravascular ultrasound confirmed nearly occlusive emboli in both the main pulmonary artery and more distal branches. Urokinase was administered with clinical improvement. Rapid Visualization of Massive Pulmonary Emboli (Tspson eta/)
ur
Fo<.l I!F I. ((pfl ): l ntravasl'!il ar ultrasouud ( 1\' ) illl.1g • pu llll on ,u·~ •mho lus (arro" ) in th • l •fliO\Vt' r lo har arlt•n . The 1\'ll · ca tlu~ ter (ci r ·lt>)nl o can h • seen within tlw lu men . B (right ): A~ th • ~·athet •r is w ithdra\\·n into thl' distal main Jlllhnon a n art<·n·. tho· intralonninal o·onholns (arrow ) can IH· Yisnalizo·d.
Dts
Fu :nn: :2 . Ti l!' onassin· l' lllholus , ·isualizl'd in tlo!' kft on a in pulnoonan· ar!!'oY \\'itlo intra\·as!'ul a r ultrasound I 1\' US l is confirool!'d u~int: po;lmonarY arto ·riot:raphY . Tlw 1\' US cath!'!o·r is positiom·d at tl11 · distal <'\lo·nt of tlo!' o·noholns .
catheter into the pulmonary arteJ!· · Although our patil'nts \\'ere transported to the interw·ntional cardiac cathl'tl'rization laboratory for furthl'r diagnostic and thl'rapeutic intetTentions, the IVUS techni
889
experienced no complications. Intravascular ultrasound identified ten segments with suspected chronic pulmonary thromboemboli in seven patients and all were confirmed at surgery. Disadvantages of IVUS include the need for introduction via a sheath providing central venous access. Such vascular invasion is best avoided, if possible, in patients receiving systemic thrombolytic therapy. However, in the latter group of patients, a definitive diagnosis is crucial. In critically ill patients, a venous sheath may already be in place or may be contemplated for intravenous access and/or pulmonary artery catheter placement. In our patients, a femoral sheath was also utilized as access for administration of low doses of intrapulmonary arterial thrombolytic therapy directly into the massive emboli. We have successfully utilized this intraembolic infusion technique in eight patients with massive PE and contraindications to standard doses of thrombolytic therapy.9 Although the main pulmonary artery and large branches can be quickly accessed and examined with IVUS, cannulation and visualization of each peripheral branch of the pulmonary arterial tree are difficult to accomplish rapidly with this technique. The complete extent of a large embolus may be difficult to determine with IVUS, but can be estimated by advancing or withdrawing the catheter past the clot. There are certain disadvantages to pulmonary arteriography. Contrast injection is performed at increased risk in patients with moderate to severe pulmonary hypertension or renal insufficiency.111 Pulmonary arteriography, however, offers a much more complete view of the entire vascular tree and remains the gold standard for the diagnosis of PE. Critically ill patients in intensive care units may be difficult to transport and would appear to be good candidates for bedside IVUS imaging when arteriography might otherwise be necessary. After placement of a femoral venous sheath, the IVUS catheter is advanced through a guide catheter that has been fluoroscopically guided into the pulmonary artery and the right and left main pulmonary arteries are examined. Although the guide catheter may not be necessary, it appears to facilitate place-
890
ment. Experience with this technique is recommended prior to its use in critically ill patients. While IVUS may not be practical for the rapid detection of smaller, peripheral emboli , it may prove to be an accurate and efficient diagnostic technique in the setting of massive emboli and could promptly provide sufficient diagnostic information to permit the initiation of potentially lifesaving therapy. Further evaluation of this technique in certain clinical settings appears warranted. REFERE:-;CES
2
.1
4
S
6
i
8
9
10
Harrison JK, Sheikh KH, Davidson CJ. Kisslo KB . Leithe MC, Himmelstein SI , et al. Balloon angioplasty of coarctation of the aorta evaluated with intravascular ultrasound imaging. JAm Coli Cardiol 1990; 15:906-09 Davidson CJ. Sheikh KH . Harrison JK . Himmelstein SI. Leithe ME. Kisslo KB . et al. Intravascular ultrasound versus digital subtraction angiography: a human ;, r;i r;o comparison of vessel size and morphology. J Am Coli Cardiol 1990; 16:633-36 Pandian NG . Kreis A. Brochway B. Detection of intraarterial thrombus by intra,·ascular high-frequency two-dimensional ultrasound imaging in vitro and in viHl studies. Am J Cardiol I 990; 65: 12RO-R3 Pandian NG . Weintraub A. Kreis A. Schwartz SL. Konstar MA. Salem DN. Intracardiac. intravascular, two-dimensional. high frequenc~· ultrasound imaging of pulmonary arte ry and its branches in humans and animals. Cir,·ulation 1990; Rl :2007-12 Tapson VF. Davidson CJ. Gurbel PA. Sheikh KH . Kisslo KB . Stack RS. Rapid and accurate diagnosis of pulmonary emboli in a canine model using intravast·ular ultrasound imaging. Chest 1991; 100:1410-13 Moser KM. Pulmonary embolism. In: Murray JF. Nadel JA. eds. Textbook of respiratory medicine. Philadelphia: WB Saunders, 1988; 1299-1327 Shure D. Moser KM. Harrell JH . Hartman MT. Identification of pulmonary emboli in the dog: comparison of angioscopy and perfusion st·anning. Circulation 1981 ; 64 :618-21 Ricou F, Nicod PH , Moser KM . Peterson KL, Catheterbased intravascular ultrasound imaging of chronic thromboembolic pulmonary disease. Am J Cardiol 1991 ; 67:749-52 Tapson VF, Da,;dson CJ, Bauman R. Newman GE, O'Conno r CM, Stack RS. Rapid thrombolysis of massive pulmonary emboli without systemic fibrinoge nolysis: intraembolic infusion of thrombol)1ic therapy. Am Rev Respir Dis 1992; 145:A719 Mills SR. Jackson DC, Older RA. Heaston DK, Moore A\'. The incidence, etiologies and avoidance of complications of pulmonary angiography in a large series. Radiology 1980; 136:295-99
Rapid Visualization of Massive Pulmonary Emboli (Tapson et at)
Massive pulmonary embolism may result in rapid deterioration prlor to diagnostic and therapeutic intervention. Intravascular ultrasound imaging has been utilized previously to evaluate vascular abnormalities as well as normal human pulmonary arteries. We employed this technique to rapidly identify massive pulmonary emboli located in the main pulmonary arteries of two patients. The presence of
these emboli was confirmed with pulmonary arteriography. Intravascular ultrasound may be utilized to rapidly confirm the presence of large proximal pulmonary emboli. (Chest 1994; 105: 888-90)
Massive pulmonary embolism (PE) results in significant mortality. Rapid recognition and initiation of therapy is crucial. Intravascular ultrasound (IV US) imaging is a relatively new technique that has been utilized to characterize a variety of vascular disorders. 1•3 While invasive, this technique does not require contrast material, and studies of normal pulmonary arteries have been performed in humans. 4 We previously reported the use of IVUS to identify experimental PE in a canine model. 5 We now report the use of this technique to visualize massive emboli located in the main pulmonary arteries of two patients.
evaluation and treatment. Aventilation perfusion scan revealed absence of perfusion to the left lung with defects in the right lung as well. In view of previous falling episodes, a brain computed tomographic (CT) scan was performed revealing evidence of small vessel disease and lacunar infarcts. Because of unstable hemodynamics in the setting of a massive pulmonary embolus with an abnormal brain CT scan, direct infusion of lowdose thrombolytic therapy was contemplated. A 9-French sheath was inserted into the right femoral vein and pulmonary artery catheterization revealed the pulmonary artery pressure to be 34/ 14 (mean, 21) . A 4.8-French 20-MHz mechanically rotated IVUS catheter (Boston Scientific, Watertown, Mass) together with a portable ultrasound console (Diasonics, Milpitas, CaliO was utilized for IVUS imaging. With fluoroscopic guidance, a pulmonary artery guide catheter was advanced to the left main pulmonary artery and the IVUS catheter, rotating at 900 rpm, was advanced through the guide catheter into the left lower lobar pulmonary artery (Fig 1, left). As it was slowly withdrawn, a large embolus was visualized in the left main pulmonary artery (Fig 1, right). Images were recorded on 1.25-cm videotape. The embolus was confirmed by pulmonary arteriography (Fig 2) . The patient received 250,000 U of urokinase directly into the massive embolus with excellent results both clinically and arteriographically, and without bleeding complications.
CASE REPORTS CASF.
I
A 76-year-old white woman was admitted to the coronary care unit for further evaluation of severe dyspnea, hypotension, and atrial fibrillation . Her medical history was remarkable for anxiety and depression as well as difficulty with her balance resulting in at least one fall. On the morning of hospital admission, the patient developed severe dyspnea and was unable to stand. She denied chest pain, cough , fever, or chills. Examination in the emergency department revealed an irregular pulse at 120/min, a respiratory rate of 24/min, and a blood pressure of 65/40 mm Hg. The left lower extremity was warmer than the right and appeared somewhat firm on examination compared with the more flaccid right calf. Results of the remainder of the examination were normal. Electrocardiography revealed atrial fibrillation and a chest radiograph suggested a prominent right main pulmonary artery but was otherwise unremarkable. Arterial blood gas analysis on room air initially revealed a pH of7.45, Po 2 of 54, and Pco 2 of 32. The patient received intravenous normal saline solution and the blood pressure improved to 130/60 mm Hg. She was transferred to the coronary care unit for further *From the Division of Pulmonary and Critical Care Medicine (Dr. Tapson) and the Division of Cardiology (Drs. Davidson and Stack and Ms. Kisslo), Duke University Medical Center, Durham , NC . Manuscript received February II, 1993; revision accepted June 30 Reprint requests: Dr. Tapson, Box jJJ75, Duke University Medical Center, Durham , NC 27710
888
IVUS =intravascular ultrasound; PE bolism
CASF.
=pulmonary
em-
2
A 66-year-old white man presented to the emergency department for further evaluation of dyspnea and presyncope. The systolic blood pressure was 90 mm Hg and an arterial blood gas analysis revealed a pH of7.46, Po2 of 42, and Pco2 of28. Ventilation perfusion scanning revealed almost complete lack of perfusion to the left lung with a smaller defect on the right. He was placed on a regimen of heparin and dopamine and the blood pressure improved to approximately 100/60 mm Hg. Because of hemodynamic instability, thrombolytic therapy was contemplated and the patient was taken to the interventional cardiac catheterization laboratory. Right heart catheterization revealed mean right atrial and pulmonary artery pressures of 16 and 70/35 (mean, 45) respectively. Large defects in the main pulmonary artery as well as in the more distal branches were demonstrated by pulmonary arteriography. An IVUS catheter was then advanced through the right heart guide catheter and over a 0.035-cm guidewire into the proximal left main pulmonary artery. Intravascular ultrasound confirmed nearly occlusive emboli in both the main pulmonary artery and more distal branches. Urokinase was administered with clinical improvement. Rapid Visualization of Massive Pulmonary Emboli (Tspson eta/)
ur
Fo<.l I!F I. ((pfl ): l ntravasl'!il ar ultrasouud ( 1\' ) illl.1g • pu llll on ,u·~ •mho lus (arro" ) in th • l •fliO\Vt' r lo har arlt•n . The 1\'ll · ca tlu~ ter (ci r ·lt>)nl o can h • seen within tlw lu men . B (right ): A~ th • ~·athet •r is w ithdra\\·n into thl' distal main Jlllhnon a n art<·n·. tho· intralonninal o·onholns (arrow ) can IH· Yisnalizo·d.
Dts
Fu :nn: :2 . Ti l!' onassin· l' lllholus , ·isualizl'd in tlo!' kft on a in pulnoonan· ar!!'oY \\'itlo intra\·as!'ul a r ultrasound I 1\' US l is confirool!'d u~int: po;lmonarY arto ·riot:raphY . Tlw 1\' US cath!'!o·r is positiom·d at tl11 · distal <'\lo·nt of tlo!' o·noholns .
catheter into the pulmonary arteJ!· · Although our patil'nts \\'ere transported to the interw·ntional cardiac cathl'tl'rization laboratory for furthl'r diagnostic and thl'rapeutic intetTentions, the IVUS techni
889
experienced no complications. Intravascular ultrasound identified ten segments with suspected chronic pulmonary thromboemboli in seven patients and all were confirmed at surgery. Disadvantages of IVUS include the need for introduction via a sheath providing central venous access. Such vascular invasion is best avoided, if possible, in patients receiving systemic thrombolytic therapy. However, in the latter group of patients, a definitive diagnosis is crucial. In critically ill patients, a venous sheath may already be in place or may be contemplated for intravenous access and/or pulmonary artery catheter placement. In our patients, a femoral sheath was also utilized as access for administration of low doses of intrapulmonary arterial thrombolytic therapy directly into the massive emboli. We have successfully utilized this intraembolic infusion technique in eight patients with massive PE and contraindications to standard doses of thrombolytic therapy.9 Although the main pulmonary artery and large branches can be quickly accessed and examined with IVUS, cannulation and visualization of each peripheral branch of the pulmonary arterial tree are difficult to accomplish rapidly with this technique. The complete extent of a large embolus may be difficult to determine with IVUS, but can be estimated by advancing or withdrawing the catheter past the clot. There are certain disadvantages to pulmonary arteriography. Contrast injection is performed at increased risk in patients with moderate to severe pulmonary hypertension or renal insufficiency.111 Pulmonary arteriography, however, offers a much more complete view of the entire vascular tree and remains the gold standard for the diagnosis of PE. Critically ill patients in intensive care units may be difficult to transport and would appear to be good candidates for bedside IVUS imaging when arteriography might otherwise be necessary. After placement of a femoral venous sheath, the IVUS catheter is advanced through a guide catheter that has been fluoroscopically guided into the pulmonary artery and the right and left main pulmonary arteries are examined. Although the guide catheter may not be necessary, it appears to facilitate place-
890
ment. Experience with this technique is recommended prior to its use in critically ill patients. While IVUS may not be practical for the rapid detection of smaller, peripheral emboli , it may prove to be an accurate and efficient diagnostic technique in the setting of massive emboli and could promptly provide sufficient diagnostic information to permit the initiation of potentially lifesaving therapy. Further evaluation of this technique in certain clinical settings appears warranted. REFERE:-;CES
2
.1
4
S
6
i
8
9
10
Harrison JK, Sheikh KH, Davidson CJ. Kisslo KB . Leithe MC, Himmelstein SI , et al. Balloon angioplasty of coarctation of the aorta evaluated with intravascular ultrasound imaging. JAm Coli Cardiol 1990; 15:906-09 Davidson CJ. Sheikh KH . Harrison JK . Himmelstein SI. Leithe ME. Kisslo KB . et al. Intravascular ultrasound versus digital subtraction angiography: a human ;, r;i r;o comparison of vessel size and morphology. J Am Coli Cardiol 1990; 16:633-36 Pandian NG . Kreis A. Brochway B. Detection of intraarterial thrombus by intra,·ascular high-frequency two-dimensional ultrasound imaging in vitro and in viHl studies. Am J Cardiol I 990; 65: 12RO-R3 Pandian NG . Weintraub A. Kreis A. Schwartz SL. Konstar MA. Salem DN. Intracardiac. intravascular, two-dimensional. high frequenc~· ultrasound imaging of pulmonary arte ry and its branches in humans and animals. Cir,·ulation 1990; Rl :2007-12 Tapson VF. Davidson CJ. Gurbel PA. Sheikh KH . Kisslo KB . Stack RS. Rapid and accurate diagnosis of pulmonary emboli in a canine model using intravast·ular ultrasound imaging. Chest 1991; 100:1410-13 Moser KM. Pulmonary embolism. In: Murray JF. Nadel JA. eds. Textbook of respiratory medicine. Philadelphia: WB Saunders, 1988; 1299-1327 Shure D. Moser KM. Harrell JH . Hartman MT. Identification of pulmonary emboli in the dog: comparison of angioscopy and perfusion st·anning. Circulation 1981 ; 64 :618-21 Ricou F, Nicod PH , Moser KM . Peterson KL, Catheterbased intravascular ultrasound imaging of chronic thromboembolic pulmonary disease. Am J Cardiol 1991 ; 67:749-52 Tapson VF, Da,;dson CJ, Bauman R. Newman GE, O'Conno r CM, Stack RS. Rapid thrombolysis of massive pulmonary emboli without systemic fibrinoge nolysis: intraembolic infusion of thrombol)1ic therapy. Am Rev Respir Dis 1992; 145:A719 Mills SR. Jackson DC, Older RA. Heaston DK, Moore A\'. The incidence, etiologies and avoidance of complications of pulmonary angiography in a large series. Radiology 1980; 136:295-99
Rapid Visualization of Massive Pulmonary Emboli (Tapson et at)