CTA For Hemoptysis 1
Jim Caridi, MD, FSIR
University of Florida
Massive hemoptysis is defined as bleeding from the lower respiratory tract in amounts ranging from 100
- 1000 cc’s in a 24 hour period. Most articles narrow this down to 300 - 600 cc’s or more realistically use
a clinical definition that includes any amount of lower respiratory bleeding that causes a life threatening Notes
event. Typically it takes approximately 400 cc to hinder oxygen transfer in alveoli. Patients die from asphyxia
not exsanguination. To complete the definitions recurrent bleeding is usually described as greater than
100 cc’s per 24 hours subsequent to therapy.
To initiate immediate and successful treatment of massive hemoptysis rapid identification of the source
and culprit vessel(s) is paramount. The differential diagnosis of hemoptysis is extensive and diverse,
including the following:
Bronchiectasis
Infection: TB, Fungal, Pneumonia
Tumor
Chronic inflammatory disease
Cystic fibrois
Pulmonary embolus
CHF
AVM
Aneurysm - pulmonary or bronchial artery
Vasculitis: Behcet’s, Wegeners
Iatrogenic
Finally in 6-10% of patients hemoptysis is considered “cryptogenic” without a known cause.
Classically, when a patient presents with persistent active hemoptysis the algorithm includes CXR,
bronchoscopy and endobronchial treatment if possible. Bronchoscopy can assist the airway with aspiration
of hemorrhage and can attempt to interrupt bleeding with iced saline, vasoconstrictors, balloon inflation
or laser therapy but this requires a skilled operator. It can localize bleeding 49 - 90% of the time but
rarely diagnoses the underlying disease or the source(s) of bleeding. In addition to the bronchoscopic
procedure taking considerable time and requiring sedation in an already respiratory compromised
patient, instrumentation and lavage may stimulate even greater hemorrhage. Theoretically it may not be
the best choice if a better one is available.
Other potential therapies include conservative management, surgery and most commonly bronchial
artery embolization. Conservative management for massive hemoptysis has a mortality rate of 50 - 100%.
Surgery carries a significant morbidity and a mortality of 7 - 18% which increases to 40% if emergent.
Bronchial artery embolization (BAE) was first described by Remy and has a complication rate of 1.4 - 6.5%.
It is now the accepted mode of therapy.
To perform accurate, precise and efficacious bronchial embolization an in depth knowledge of anatomy
and potential sources of bleeding is essential. Bronchial arteries supply the intra and extra pulmonary
airways, vasa vasorum of pulmonary arteries, visceral pleura, trachea, esophagus and lymph nodes. They
anastomose with the pulmonary artery through a thin fragile capillary network and essentially contribute
to a dual blood supply to the lung. Hypertrophy and tortuosity can occur with inflammation or neoplasm.
Increased pressure in these weakened fragile networks can lead to rupture into the bronchi and alveoli.
Classically bronchial arteries arise from the descending thoracic aorta at approximately the T5 -T6 level.
These are known as orthotopic. They approximate 1.5 mm in size at their origin, course through the hilum
parallel to the airways and taper distally to about .5 mm. Their origin anatomy is extremely variable and
there are at least 9 documented variations. Bronchial arteries can be ectopic or anomalous in 20 - 30%.
They typically arise from the concavity of the aorta but also from the arch of the aorta, IMA, thryocervical
CTA For Hemoptysis 2
Jim Caridi, MD, FSIR
University of Florida
trunk, subclavian, axillary, costocervial and inferior phrenic arteries. As opposed to non bronchial systemic
arteries they have the same parallel course as orthotopic bronchial arteries.
Notes
Non bronchial systemic arteries arise from the arch of the aorta, IMA, thyrocervical trunk, intercostal,
subclavian, axially, costocervical and lateral thoracic arteries. The inferior phrenic artery is also a major
contributor which is just as variable with potential origins from the aorta, celiac, gastric, hepatic, SMA and
even spermatic artery.
Classically, bronchial arteries are the source of bleeding in 90%. Non - bronchial systemic arteries represent
a 5% source with the pulmonary artery representing another 5%. However in those patients with bleeding
and massive hemoptysis non-bronchial systemic arteries contribute, 40% and 90%, respectively. For
complete, permanent control of bleeding they must be addressed. Considering the anatomic variations
and the number of potential sources of bleeding, localizing all the sources of bleeding can be a roll of
the dice.
Bronchial artery embolization has a clinical success of 75%. Immediate (within 24 hours), 1 month, long term
(greater than 1 month), recurrence rates approximate 3%, 3-27% and 10 - 52%, respectively. Considering
the success of a multitude of other embolic procedures performed by interventional radiologists the
success of BAE pales in comparison. Immediate recurrence is likely due to incomplete embolization
or more probably failure to recognize ectopic or non bronchial systemic artery sources. Long-term or
delayed recurrence may be the result of incomplete embolization, recanalization of embolized vessel,
revascularization of collaterals, progression of disease and again failure to recognize other sources of
bleeding.
The failure to recognize other sources of bleeding is not necessarily the fault of the operator. Aortic
angiography can miss culprit vessels and selective injections may be necessary. However, the angiographic
search for normal, anomalous and non-bronchial systemic arteries especially if they require selective
injection can be overwhelming and in fact have negative clinical consequences. These include renal
failure and non target embolization.
Considering the paragraphs above, it makes good medical sense that a more global non-invasive
procedure like CTA be utilized initially. It not only rapidly diagnoses the underlying potential etiology of
bleeding but also can localize the culprit vessel(s) so that quick efficient embolization can be performed
with limited morbidity. Typically a CTA is performed with 100-120 cc IV contrast (350 mg/dl) at 4 - 5 cc/sec,
1 mm sections from neck to renal arteries. The images are reformatted and volume rendered.
Common areas to look for abnormal bronchial arteries include the retrotracheal, retroesophageal space,
aortopulmonary window and the posterior wall of the main bronchus. CTA findings that correlate with
hemorrhage include dilated (> 2mm), tortuous vessels, hypervascularity, parenchymal stain, AV shunting,
contrast casting of the bronchus, aneurysm and extravasation. Other findings include vessels that extend
to and beyond the hilum of the lung, non-tapered vessels, ground glass opacity and alveolar consolidation.
Yoon reported that pleural thickening width > 3 mm and enlarged vascular structures within extrapleural
fat were good indicators of a non-bronchial supply of bleeding.
Studies of CTA used for defining hemoptysis have shown it localizes the site of bleeding equal to or
greater than bronchoscopy 63 -100%. It is better for depiction of bronchial and non-bronchial systemic
arteries than angiography detecting 90-100% of bronchial and 60-80% of non-bronchial arteries causing
hemoptysis. CTA sensitivity is less for acute disease when compared to chronic.
CTA For Hemoptysis 3
Jim Caridi, MD, FSIR
University of Florida
To sum up the attributes of CTA for the diagnosis of hemoptyis it is a rapid diagnostic test with minimal
morbidity. It can diagnose both the underlying disease and etiology of bleeding better than bronchoscopy
while localizing the site of bleeding just as well. It can recognize pulmonary embolus, bronchial and Notes
pulmonary artery aneurysms not apparent to bronchoscopy. By identifying the actual source of bleeding
it provides a roadmap for rapid, safe, complete embolization which eliminates unnecessary searching and
more importantly reduces the recurrence of bleeding.
References
1. Carvalho P, Anderson D, Charan N. Bronchial imaging using helical computed tomography
Pulmonary pharmacology and therapeutics 2007;20:104-108
2. Jeong YJ, Chang WK, Kun-Il K et al. Prediction of recurrent hemoptysis with MDCT angiography. J Comput Assist Tomogr
2006;30:662-668
3. Yoon, YD, Lee KS, Jeong YJ, et al. Hemoptysis bronchial and non bronchial systemic arteries at 16-detector row ct. Radiology
2005;234:292-298
4. Remy-Jardin M, Duhamel A, Deken V et al. Systemic collateral supply in patients with chronic thromboembolic and primary
pulmonary hypertension: Assessment with multi-detector row helical CT angiography. Radiology 2005;235:274-281
5. Khalil A, Fartoukh M, Tassart M, et al. Role of MDCT in Identification of the bleeding site and the vessels causing hemoptysis.
AJR 2007;188:117-125
6. Hiwatashi A, Oshida K. The origin of right inferrior phrenic artery on multidetector row helical CT. Journal of Clinical Imaging
27;2003:298-303.
7. Bruzzi JF, Remy-Jardin, Delhaye D. Multi- detector row CT of hemoptysis Radiographics 2006;26:3-22
8. Mori H, Ohno Y, Tsuge Y. Use of multidetector row CT to evaluate the need for bronchial arterial embolization in hemoptysis
patients. Respiration;2010:80(1)24-31
9. Yoon W, Kim JK, Kim YH et al. Bronchial and non bronchial systemic artery embolization for life-threatening hemoptysis: a
comprehensive review. Radiograpics 2002;22:1395-1409