Summary
Background. Patients with venous thromboembolic disease may present with different clinical
manifestations. Factor V Leiden mutation leading to resistance to activated protein
C is associated with a sevenfold increased risk for presenting with deep-vein thrombosis.
It is not yet established whether carriers of the mutation have a similarly increased
risk for manifesting with pulmonary embolism.
Methods. From an Anticoagulation Clinic monitoring coumarin therapy, a consecutive series
of patients with a first thromboembolic event (objectively proven by current radiological
methods) were enrolled. All patients were interviewed and blood was drawn for geno-typing.
From the hospital charts and the personal interview, information was obtained on acquired
risk factors and the signs and symptoms on hospital admission.
Results. 45 patients presented with symptoms of pulmonary embolism only, 211 had only symptoms
of deep-vein thrombosis whereas 23 had clinical features of both. In about half of
the patients acquired risk factors for venous thromboembolism were present which did
not differ between the three groups of patients. Recent surgery had been performed
more often in patients presenting with pulmonary embolism than in other patients (33.3%
vs. 18.5%, p <0,05). Factor V Leiden was present in 9% of the patients presenting
with pulmonary embolism (relative risk: 3.3 95% Cl: 1.0-10.6) and 17% of the patients
presenting with deep-vein thrombosis (relative risk: 6.9 95% Cl: 3.6-12.8). The prevalence
of factor V Leiden was intermediate in patients with both clinical characteristics.
Conclusion. These data suggest that patients with venous thromboembolism have different clinical
presentation depending on the risk factor profile. Factor V Leiden may preferentially
lead to manifest deep-vein thrombosis. Differences in structure of venous thrombi
could underlie differences in embolic tendency.
