Localized Intravascular Coagulopathy
Slow-flow vascular malformations, especially those with a large venous
component can frequently be complicated by intralesional thrombosis and
if ectatic vessels are connected to larger feeding veins this can put
patients at risk for venous thromboembolism (VTE)5-11.
Although the mechanism is not fully elucidated, venous stagnation can
lead to activation and consumption of coagulation factors and platelets
and result in localized intravascular coagulopathy (LIC). Pain is often
correlated to LIC and is a common symptom of slow-flow vascular
malformations resulting in decrease of quality of life and worse
outcomes12,13. Pain in this group is complex occurring
in the acute and chronic setting often associated with intralesional
thrombi. The pain may also involve several contributing factors which
include chronic venous insufficiency, inflammation, infection,
arthritis, and neuropathic pain14.
LIC may worsen during a surgical or interventional procedure where the
abnormal vasculature is perturbed leading to post-operative bleeding or
thrombotic complications. Large excisions or prolonged intravascular
procedures seem to be the highest risk procedures. There are no
evidence-based guidelines for peri-operative management of LIC to
mitigate the risk of hematologic complications. Sirolimus has been shown
to reduce the coagulopathy and for minor procedures these patients may
not require additional anticoagulation15. However, for
complex surgical procedures and in patients with laboratory evidence of
LIC, anticoagulation before and after the procedure may be
warranted16.
Recognizing pediatric and adult patients with vascular tumors and
malformations that are predisposed to coagulopathy is important. The
rapidly growing field of surgical and medical management of vascular
anomalies include medications that may improve or worsen the
coagulopathy. Early identification will help improve outcomes in this
patient population. Although there are no consensus guidelines, this
review will help provide guidance in the therapeutic approach for
management of coagulopathy in patients with vascular anomalies based on
our current practice and review of the available literature.
2 | DIAGNOSTIC APPROACH
Appropriate management relies on accurate diagnosis. Historical data of
the vascular malformation such as first appearance, growth, and
aggravating factors are important. Physical exam, imaging and laboratory
evaluation are essential in diagnosis and determining what treatment, if
any, is needed. Conventional coagulation parameters that include
complete blood count (CBC), prothrombin time (PT), activated partial
thromboplastin time (aPTT), fibrinogen, and D-dimer vary in specific
vascular anomalies that are predisposed to coagulopathy (Table 1).
3 | CONSULTATION WITH THE HEMATOLOGIST