Bleeding is one of the complications associated with percutaneous coronary intervention from the femoral route due to the use of potent antiplatelet therapies including adenosine diphosphate receptor blockers and glycoprotein IIb/IIIa inhibitors. Complications include haematoma, retroperitoneal haemorrhage, pseudoaneurysm, arteriovenous fistula, arterial occlusion, femoral neuropathy and infection. Complications for diagnostic procedures are lower due to the lack of antiplatelet therapies on board. Often, incorrect location of the femoral artery puncture site results in complications. Puncturing below the femoral bifurcation can result in psedoaneurysm, haematoma and arteriovenous fistulas, whereas retroperitoneal haemorrhage is caused by high femoral punctures. Identification of bleeding and vascular complications is paramount as bleeding is associated with adverse events. Techniques to reduce the risk of femoral arterial complications include the use of ultrasound scan or fluoroscopy guided femoral punctures. Furthermore, the micropuncture technique has been shown to reduce complications but is not widely adopted. Ultimately, the radial route is preferable to the femoral route as vascular complications are significantly lower.
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Introduction
The incidence of vascular complications during diagnostic coronary angiography is 0.44–1.8% and can affect up to 4% of percutaneous coronary intervention (PCI) procedures.1,2 The common femoral artery (CFA) is the optimal site for punctures, as this is relatively large and can accommodate larger sheath sizes.3 Access site complications are reduced when the puncture is located between the inferior epigastric artery and above CFA bifurcation. Using ultrasound scan (USS) or fluoroscopy to aid in the optimal puncture site reduces the risk of complications. Non-modifiable risk factors for complications include advanced age, renal failure, low body mass index, female gender and hypertension. Training healthcare professionals in the management of femoral punctures post-procedure is one of the first steps in identifying problems and managing them promptly.
The ideal puncture should be above the femoral bifurcation but 1–2 cm below the inguinal ligament. The inguinal ligament extends from the anterior superior iliac spine to the pubic tubercle (figure 1).4 Some operators may use the inguinal skin crease as a marker for the location of the CFA, but this is a poor marker, as punctures distal to the CFA can occur in 72% of patients.3 Often, femoral punctures are performed blindly, hence, increasing the likelihood of vascular complications. The use of fluoroscopy or USS guided femoral punctures are associated with significantly lower incidence of vascular complications. In one study, pseudoaneurysms were seen in 0.3% of cases done under fluoroscopy and 1.1% when a blind puncture was performed (p=0.017). Arterial injury was prevalent in 1.9% of patients who had punctures performed blindly and 0.7% in those who had punctures performed under fluoroscopy (p<0.01). Duration of hospital stay was shorter among patients who had coronary angiography performed under fluoroscopic guidance (figure 2).5
Types of complications
Complications of femoral punctures include haematoma, retroperitoneal haemorrhage, pseudoaneurysm, arteriovenous fistula, arterial occlusion, femoral neuropathy and infection. Puncturing below the femoral bifurcation can result in pseudoaneurysm, haematoma and arteriovenous fistulas, whereas retroperitoneal haemorrhage is caused by high femoral punctures.
Vessels below the bifurcation are smaller than the CFA and may not be large enough to accommodate bigger sheaths. Compression at these sites tends to be distributed to the soft tissue making effective haemostasis less likely, and may result in a haematoma or pseudoaneurysm.6
Haematomas result due to punctures made below the femoral bifurcation. They account for 5–23% of PCI complications. Blood collects in the soft tissues and, depending on the size of the haematoma, there can be a drop in haemoglobin levels and blood pressure.7 Treatment involves bed resting and applying pressure slightly above the puncture site, without obstructing blood flow to the lower limbs by assessing the distal pulses – popliteal, dorsalis pedis and posterior tibial. Haemoglobin levels should be checked to ensure there is no significant decrease at a level requiring transfusion. The skin should be marked to observe for any spread. Often haematomas can take weeks to resolve as it is absorbed into tissues (figure 3).
Retroperitoneal haemorrhage (RPH) occur from punctures made above the inguinal ligament. They account for 0.15–0.44% of PCI complications. Bleeding occurs behind the serous membrane lining the wall of the abdomen and pelvis. This should be suspected if the patient complains of abdominal or flank pain. Bruising may be seen on the lower abdomen. The patient’s blood pressure and haemoglobin levels may decrease with tachycardia. Diagnosis is confirmed by computerised tomography (CT) scan. RPH can be fatal, so early recognition is crucial. Treatment involves bed resting, transfusing blood, as required, and early involvement of the surgical team.
Pseudoaneurysm, also known as a false aneurysm, can result from punctures made below the femoral bifurcation, difficulties in obtaining femoral access, inadequate compression of the femoral puncture site after sheath removal and impaired haemostasis. Pseudoaneurysms account for 0.5% to 9% of PCI complications. There is a communication between the femoral artery and one of its weaker walls. Blood can escape from the artery into the surrounding tissue. Symptoms include a painful swelling at the puncture site, bruising or pulsatile mass at the femoral site. There may be nerve compression from the haematoma. This should be suspected when the level of pain is out of keeping to the size of haematoma. Nerve compression can result in limb weakness, which can take weeks or months to resolve. Pseudoaneurysms are diagnosed by USS of the femoral artery. Treatment is largely dependent on the size of the pseudoaneurysm and, in general, patients should be advised to bed rest. Small femoral pseudoaneurysms can be managed conservatively as they tend to close spontaneously. Large femoral pseudoaneurysms may require USS guided compression for up to 30 minutes, USS guided thrombin injection or surgical intervention.
An arteriovenous fistula is a communication between the femoral artery and femoral vein after sheath removal and can result from multiple femoral arterial access attempts. It is seen in 0.2% to 2.1% of cases. Patients are generally asymptomatic but may have a bruit or tender swelling at the access site. In extreme cases, there may be limb ischaemia or development of deep venous thrombosis. Diagnosis is confirmed by USS. Treatment initially involves conservative management, as arteriovenous fistulas may resolve spontaneously, but in rare circumstances, USS guided compression or surgical repair may be necessary.
Arterial occlusion accounts for <0.8% of cases. Thrombi can develop at the site of the sheath and embolisation may occur after sheath removal. Symptoms include limb pain, paraesthesia, paralysis, absent/weak pulse and change in the colour of the limb. Diagnosis is often made clinically and USS Dopplers aid localising the area of occlusion. Treatment strategy includes conservative treatment, anticoagulation, thromboembolectomy or surgery. The choice of treatment is dependent upon the size of embolus, location and degree of ischaemia.
Infection accounts for <0.1% of cases. This results from poor hygiene or prolonged periods of sheath retention in the femoral artery. The use of femoral access closure devices increases the risk of infection. Symptoms include pain, swelling, erythema or discharge at the access site. Treatment involves antibiotic administration.8-11
Haemostasis after PCI
Treatment largely depends on the type of complication. There are four main methods to achieve haemostasis after PCI; manual compression, mechanical compression, vascular closure devices and the reversal of anticoagulation. Manual compression needs to be applied as the sheath is removed by placing the index and middle fingers 1 to 2 cm above the site of sheath removal. Manual compression requires application of sustained pressure for 15 to 20 minutes. If hand/finger fatigue develops, the amount of pressure applied decreases and, hence, increases the risk of bleeding. Mechanical compression, however, enables constant pressure on the artery to achieve haemostasis. Mechanical compression has been found to be as effective as manual compression for achieving haemostasis.
Vascular closure devices consist of either sutures or collagen plugs. The device should be deployed after confirmation, by femoral angiography, of the absence of significant peripheral vascular disease, and to ensure that the puncture site has been made above the common femoral artery bifurcation but below the inferior epigastric artery. Collagen plugs seal the puncture site by stimulating platelet aggregation and the release of coagulation factors, which results in the formation of a clot.12,13 Vascular closure devices allow for controlled haemostasis, early mobilisation and lower complication rates when compared with manual compression. However, there is no real improvement in clinical outcomes when compared with manual compression.14 In cases where the vascular closure device fails, manual compression must be applied to accomplish haemostasis.
The majority of patients undergoing coronary procedures are prescribed antiplatelets for acute coronary syndromes and, often, concomitant anticoagulation for atrial fibrillation, prosthetic heart valves or treatment of thrombosis. These patients are particularly prone to bleeding if there are multiple attempts at obtaining femoral access or the incorrect puncture has been made.12 Furthermore, the use of intravenous heparin for coronary procedures may cause excess bleeding in the event of a femoral complication. Treatment of bleeding involves waiting for spontaneous elimination of the drug, but this may not be feasible if the drug has a long half-life. Alternatively, the effects of the drug can be reversed with an antidote, if available. The choice of treatment depends on the severity of the bleeding and patient haemodynamics. If a femoral complication occurs, the activated partial thromboplastin time (APTT) should be measured if heparin was administered. If the APTT is prolonged, protamine should be prescribed to reverse the anticoagulant effect. In patients who are prescribed warfarin, but require reversal for major bleeding, intravenous vitamin K is recommended with prothrombin complex. If major bleeding occurs while a patient is taking a non-vitamin K antagonist oral anticoagulant (NOAC), such as dabigatran, rivaroxaban, edoxaban or apixaban, then a discussion with a haematologist is advised. Prothrombin complex concentrate can be prescribed for patients taking these drugs, but there is no clinical evidence for this. Praxbind is the approved antidote for dabigatran, but there is no approved antidote for rivaroxaban, edoxaban or apixaban.15
Prevention of femoral vascular complications
Vascular complications can be reduced by using USS or fluoroscopy guided femoral punctures or using a smaller needle to access the femoral artery. Femoral complications can be completely eliminated by using the radial route to access the coronary circulation.
The ideal puncture should be made between the inferior epigastric artery and above the common femoral artery using an USS or fluoroscopy. Once the anatomic landmarks have been identified, the needle should be angled at approximately 30 degrees from the horizontal position. When the femoral artery has been accessed, the J-wire is advanced. If there is any resistance, the wire should be removed and the needle redirected. Fluoroscopy should be used to ensure that the wire is following the right course.16
The use of USS guided access for central venous access is well recognised. USS guided femoral punctures are sparingly used, but evidence suggests favourable outcomes. The use of USS reduces femoral arterial complications by 49% when compared with manual palpation. The risk of pseudoaneurysm is reduced from 4.5% to 2.6% when USS is used.17 USS enables physicians to visualise the position of the needle, the CFA and its bifurcation, inferior epigastric artery and calcified plaques. USS should be used in obese patients, those with an impalpable femoral artery, presence of deep or small calibre vessels, patients with multiple previous catheterisation procedures and patients who are anticoagulated, where it is important to achieve access on first attempt.16,18,19 In a randomised trial of 280 patients, complication rates were lower in patients who had USS guided femoral punctures compared with the manual palpation. Furthermore, the total number of attempts to successfully achieve femoral access and the time to sheath insertion was lower with USS use.20 In another study, the use of USS was superior to fluoroscopy guided femoral access since there was a significant reduction in the number of femoral punctures and vascular access related complications in the USS group.21
Further techniques to reduce complications include a micropuncture, which involves a 21-gauge needle, in comparison with the 18-gauge needle that is commonly used, which is 56% larger and results in six times the blood flow rate during a puncture.22
The coronary circulation can be accessed by the femoral or radial route. The radial artery is superficial and easily compressible allowing haemostasis, which can be more difficult with the femoral route. Multiple trials have demonstrated the superiority of the radial route over the femoral route due to lower bleeding events and vascular access site complications.23-27 Bleeding is associated with adverse outcomes including stroke and death.28 Major bleeding is reduced by 72% when using the radial route over the femoral route. There is also a reduction in the composite of death, myocardial infarction (MI) and stroke; 2.5% in radial route versus 3.8% in femoral cases. Length of hospital stay is significantly shorter by 0.4 days with the radial route.29
Risk factors for vascular access complications
These include sex, advanced age, body mass index (BMI), hypertension, renal dysfunction, use of antiplatelets, anticoagulation and sheath size. One study found that there was higher use of contrast, renal complications, bleeding, vascular access complications, blood transfusions, major adverse cardiac events and death in patients who had PCI performed with 7-French and 8-French guides when compared with 6-French guides.6
Females undergoing PCI procedures are often older than males and have a higher incidence of comorbidities. They tend to have a higher frequency of vascular access related complications when compared with males, although angiographically they have fewer high-risk features.30
Age is one of the strongest predictors of major bleeding,31 and this tends to be encountered in patients above the age of 70 years.32-35 These patients are more likely to bleed due to local vascular changes or more advanced vascular disease.
A lower BMI is a risk factor for vascular complications. A study of patients who had an acute coronary syndrome undergoing PCI found that although obese patients (BMI >30 kg/m2) have more cardiovascular risk factors, they have a shorter hospital stay and lower 12-month mortality than patients with a normal BMI.36 Obesity is linked to impaired fibrinolysis and increased platelet aggregation. A further study examining the role of BMI in 16,783 patients who underwent PCI found that the risk of major bleeding was higher in underweight patients when compared with obese patients.37
Hypertension may increase the patient’s risk of vascular access complications. Patients with a higher systolic blood pressure (135 vs. 129 mmHg) were significantly more likely to have complications than were patients with lower blood pressures.7 In a study of 13,819 patients, 4.7% of patients who experienced major bleeding were more likely to have hypertension than patients without major bleeding.34 Therefore, it would seem reasonable to remove the sheath once the blood pressure is at an acceptable level to reduce the risk of bleeding. At present, there are no evidence-based blood pressure guidelines for such patients.
Renal dysfunction, defined as creatinine clearance less than 60 ml/min, has been consistently identified as a major risk factor for bleeding in patients undergoing PCI. Renal dysfunction tends to be present in elderly patients, those with a history of atherosclerosis and multiple comorbidities. It is important to check renal function, and be aware of potential drug interactions. Patients who have impaired renal function are at increased risk of bleeding complications in the presence of anticoagulants and antiplatelet medications, as these are excreted at a slower rate.38-41
Conclusion
Femoral arterial complications are predominantly seen in patients who have femoral punctures perfomed blindly. The risk of bleeding is increased with advanced age, hypertension, low BMI, renal impairment and the use of antiplatelets and anticoagulants. The use of USS or fluoroscopy guided femoral punctures have demonstrated a reduction in vascular complications, especially in patients in whom femoral access can be challenging. When feasible, it is preferable to use the radial route over the femoral route, as vascular complications are significantly lower with the radial route.
Conflict of interest
None declared.
Key messages
- Non-modifiable risk factors for bleeding complications include female gender, low body mass index, renal failure and hypertension
- The use of ultrasound scan guided femoral puncture reduces the risk of femoral arterial complications and is particularly useful in obese patients, non-palpable arterial pulse, patients taking anticoagulation, presence of peripheral vascular disease and those with multiple previous catheterisation procedures
- Aim to perform coronary intervention through the radial route to reduce the risk of vascular related complications.
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