Local Endovascular Complications and their Management

Etiology and Manifestations

Hematomas can result from difficult access, multiple access attempts, or inadequate closure or compression at the completion of the procedure. ^, For access, adequate compression should be used after an attempt to obtain hemostasis and this can be variable based on needle size. Further, back wall injury or leakage around the sheath can contribute to hematoma formation. Routine ultrasound use has been shown to decrease the risk of post-procedure hematoma. Routine and selective ultrasound guidance was used by 27% and 73% of interventionalists in the Vascular Study Group of New England. The overall post-procedural groin hematoma rate after PVI was 4.5%. However, the rate of combined moderate and major hematoma was 0.8%. Ultrasound-guided access was protective against hematoma overall and particularly in patients aged greater than 80 years, obese patients, and those with a sheath size >6F. Larger sheath size has been associated with minor, but not major hematoma, development.

Management

Treatment strategies for groin hematomas generally consist of observation as well as correction of any underlying coagulopathy. Transfusion may be required. Manual compression should be applied to hematomas that have been identified in the acute setting. Similarly, mechanical compression devices such as the FemoStop (Radi Medical Systems, Wilmington, MA) or C-clamp have demonstrated benefit in reducing bleeding complications. Computed tomography (CT) can be useful to assess the extent of the hematoma, the level of the defect, and to assess for active bleeding as evidenced by a contrast-induced blush ( Fig. 52.1 ). Moreover, imaging is prudent with large hematomas to rule out extension into the retroperitoneum, especially when associated with hemodynamic instability. In cases without hemodynamic instability or retroperitoneal bleeding, laboratory assessment of hematocrit levels should be performed every 4 to 6 hours until stabilization. Furthermore, interval duplex assessment should be performed to rule out the development of a pseudoaneurysm. Although most of these patients can avoid an intervention, time to ambulation is delayed and length of stay tends to be longer. The incidence of hematomas requiring transfusions in the coronary literature have been reported as 1.8% and was associated with both in-hospital mortality and 1-year mortality. Groin exploration with evacuation of the hematoma is warranted in the setting of hemodynamic instability, persistent anemia despite transfusions, skin necrosis, nerve compression, or severe pain.

Manifestations and Diagnosis

Clinical findings of retroperitoneal hematomas are often subtle and less obvious than with groin hematomas. The most common symptoms are hypotension followed by diaphoresis, groin pain, abdominal pain bradycardia, and back pain. The diagnostic test of choice for retroperitoneal hematoma is abdominopelvic CT ( Fig. 52.3 ).

Management

Treatment for a retroperitoneal hematoma is tailored to the clinical status of the patient. Indications for intervention include neurologic deficits in the affected extremity, hemodynamic instability, ongoing blood loss, and severe pain. Decompression of a retroperitoneal hematoma can be performed either through a groin incision or through an incision above the inguinal ligament to gain direct access to the retroperitoneum and iliac vessels. The arteriotomy must be exposed and repaired for optimal therapy. A covered stent can also be used to obtain control of bleeding especially if the arterial injury is above the inguinal ligament, avoiding a more morbid operation both for small and large bore femoral artery access. Care should be taken to avoid covering the deep femoral artery.

Etiology, Manifestations, and Incidence

An arteriovenous fistula (AVF) in the groin is a rare complication of percutaneous access and involves a communication between the femoral artery and vein. The incidence has been reported as 0.5%–0.86%. ^, AVF after coronary interventions has been associated with high heparin dosage, warfarin use, left-sided access, hypertension, simultaneous femoral artery and vein access and female gender. Within 12 months, 38% of all AVF closed spontaneously. None of the risk factors for AVF influenced the incidence or the rate of AVF closure. An AVF usually occurs after inadvertent low puncture of the CFA bifurcation or the profunda femoris artery and vein, which run near the superficial femoral artery (SFA). However, an AVF may also develop after through-and-through puncture of the CFA or SFA into the common femoral vein. Groin AVFs are generally asymptomatic and detected on physical examination by the presence of a palpable thrill in the groin or auscultation of a continuous bruit. Duplex ultrasound is the imaging study of choice and demonstrates the characteristic systolic–diastolic flow pattern with arterialization of the venous signal ( Fig. 52.4 ).

Management

Treatment options include observation alone, surgical repair, and endovascular repair. Ultrasound-guided compression had historically been used to treat groin AVF, but success rates have been low. If conservative management is implemented, patients should have follow-up duplex surveillance and physical examination. Symptoms can include distal ischemia or cardiac dysfunction. If symptoms arise or the fistula increases in size, surgical treatment is indicated. Endovascular management of femoral AVFs has been reported with the advent of balloon-expandable stent grafts. Coverage of the fistula with a covered stent graft results in immediate abolishment of the AVF without the need for surgery and therefore is optimal for high-risk candidates who may have failed conservative management. There have been published series using thrombin infection, although there can be a risk of arterial or venous embolization. The decision whether to treat an AVF with open, endovascular, or conservative measures is still under debate and should be driven by surgeon experience and the patient’s overall symptomatology and comorbid conditions.

Etiology and Manifestations

A pseudoaneurysm (PSA) may develop post-procedure if the arteriotomy has not adequately sealed once the sheath is removed. There is communication with the arterial lumen, and blood spreads into the surrounding soft tissue. It is a “pseudo” aneurysm in that no elements of the arterial wall are incorporated in the aneurysm sac; the wall of the PSA consists solely of compressed thrombus and surrounding soft tissue. PSAs can be differentiated from hematomas by arterial flow into the PSA with a defined neck that tracks to the arteriotomy.

The incidence of PSA formation after percutaneous procedures in contemporary series is less than 1%. ^, The cause of a PSA is often related to an inability to adequately compress the vessel or closure device failure after removal of the sheath. This occurs most frequently with SFA or low CFA puncture because the femoral head sits more cephalic and compression is insufficient. Other associated risk factors include older age, female sex, obesity, larger sheath size, anticoagulation and antiplatelet use, and manual compression. On physical examination, a systolic bruit can be auscultated and is associated with the pulsatile groin mass. When there is clinical suspicion of a PSA, groin arterial duplex examination should be performed (see Ch. 22 , Vascular Laboratory: Arterial Duplex Scanning). The typical ultrasound appearance of a PSA is an echolucent sac that is pulsatile, and with the addition of color Doppler, a swirling flow pattern is noted within this sac ( Fig. 52.5 ). On spectral waveform analysis the characteristic “to-and-fro” flow pattern can be discerned and is pathognomonic for PSA. ^, If the PSA has significant extension into the retroperitoneum, abdominopelvic contrast-enhanced CT may be of benefit to evaluate its size, as well as identify additional arterial injury sites (see Ch. 29 , Computed Tomography).

Management

Historically, an open operation was the primary recommended therapy for large or expanding PSAs to decrease the complications of nerve compression, distal embolization, or skin necrosis. Contemporary treatment is often minimally invasive, and ultrasound guided compression has been advocated. In the largest series published to date, success rates ranged from 74% to 93%. The main factors impeding successful ultrasound-guided compression include anticoagulation at the time of compression, size of the PSA, and patient discomfort. Risks associated with ultrasound-guided compression include PSA rupture, distal embolization, and thrombosis of the femoral vein or artery. ^,