Discussion
A recent retrospective review of all peripheral vascular complications after femoral artery catheterization gave the incidence of DVT as 0.05% (5 cases among 10450 cardiac diagnostic or therapeutic catheterizations).1) Although DVT is a rare complication after diagnostic transfemoral catheterization, its incidence may be higher, but most thrombotic and pulmonary embolic complications are not clinically evident, and their true incidence may be underestimated.2)
Risk factors demonstrated for venous thromboembolism (VTE) include old age, prolonged immobility, malignancy, major surgery, multiple trauma, prior VTE, chronic heart failure, and inherited or acquired thrombophilia.3) In addition, some medications such as oral contraceptives or hormone replacement therapy are also reported to be risk factors for VTE.3)4)
Prolonged bed rest, immobility of a catheterized extremity, groin compression, and large hematomas compressing the femoral vein, may all cause a predisposition to venous thromboembolic complications following femoral catheterization and may increase the incidence of such complications in combined left and right heart catheterization or therapeutic cardiac catheterization performed with large-sized sheaths.1)2)
The femoral approach is the most commonly used route for diagnostic CAG. Prophylactic anticoagulation may not be necessary in stable patients without other known risk factors who are undergoing elective diagnostic CAG expected to last less than 30 minutes. However, for a procedure thatis expected to last longer than 30 minutes, it may be advisable to administer an anticoagulant to prevent thrombus formation.5) Access site hemostasis is generally achieved by manual compression after sheath removal. Manual compression leads to immobilization of the patient for several hours.6) However, recent studies have suggested that the length of bed rest thought to be necessary after sheath removal appears to be decreasing, and early ambulation after removal of the sheath has been shown to be safe, in certain settings, and may improve patient comfort.7-9)
Previous reports have suggested that medication for psychiatric disorders may increase the risk of VTE.10) Many studies regarding the possible association between antipsychotic drugs and VTE have been published, and most of them have suggested that antipsychotics tend to increase the risk of VTE. In addition, a few clinical studies and isolated case reports have pointed to an association between the use of antidepressant drugs and VTE.11)12)
In the present case, DVT developed unusually after transfemoral diagnostic CAG of an apparently normal coronary artery in the absence of any risk factors for VTE. We suggest that compression of the groin and subsequent prolonged immobilization, as well as the use of antidepressant drugs, may be risk factors for DVT following CAG.
This case demonstrates that clinicians should consider the possibility of a VTE after diagnostic CAG even when patients lack significant risk factors. A protocol using smaller sheath sizes, close observation, and early ambulation after proper manual compression of the femoral artery may be a good approach to ensuring patient safety. Moreover, prophylactic anticoagulation during CAG may be helpful to prevent VTE in patients using antidepressants or anxiolytics.