Evaluating the safety and outcomes of catheter directed thrombolysis following catheter fragmentation in acute high risk pulmonary embolism

Acute pulmonary embolism is common, but its presentation highly varies ranging from asymptomatic to massive pulmonary embolism. Massive pulmonary embolism is a common life-threatening condition and represents the most serious manifestation among venous thromboembolic disease.

Acute pulmonary embolism is considered the third most common cause of death among hospitalized patients . The mortality rate can exceed 58% in patients with acute pulmonary embolism presenting with haemodynamic instability , mostly occur within 1 hour of presentation.

In patients with high risk pulmonary embolism , the main aim of therapy is to rapidly recanalize the affected pulmonary arteries with thrombolysis or embolectomy; to decrease right ventricular afterload and reverse right ventricular failure and shock, prevent chronic thromboembolic pulmonary hypertension , and decrease the recurrence risk.

The first-line treatment in patients with acute high risk pulmonary embolism presenting with persistent hypotension and/or cardiogenic shock is intravenous thrombolytic therapy. However a significant proportion of patients may not be a candidate for Intravenous thrombolysis because of major contraindications. An alternative option in patients with absolute contraindications or has failed intravenous thrombolysis is surgical embolectomy , but the number of experienced tertiary care centers that can do emergency surgical embolectomy are limited.

Percutaneous catheter mechanical fragmentation of proximal pulmonary arterial clots followed by local thrombolytic therapy is accepted as an alternative to intravenous thrombolytic therapy and surgical embolectomy because of their ability to rapidly recanalize occluded pulmonary blood flow. Several reports have shown that catheter-directed therapy is a safe and effective treatment for acute PE to restore pulmonary flow and decreasing Pulmonary artery systolic pressure , However, current knowledge on efficacy and safety of catheter-directed therapy in management of intermediate high risk pulmonary embolism is limited.

Inclusion Criteria:

• Patients with angiographically confirmed acute high risk pulmonary embolism with shock index >1.
• Pulmonary arterial occlusion with >50% involvement of the central (main and/or lobar) pulmonary , and pulmonary hypertension (mean pulmonary artery pressure >25 mmHg)
• Patients with high risk pulmonary embolism who remain unstable after receiving fibrinolysis
• Patients with high risk pulmonary embolism who cannot receive fibrinolysis
• Patients with acute intermediate-high risk pulmonary embolism with adverse prognosis (new hemodynamic instability, worsening respiratory failure, severe RV dysfunction, or major myocardial necrosis)

Exclusion Criteria:

• Patients with echocardiographically confirmed right sided thrombi.
• Patients with low-risk pulmonary embolism or intermediater-low risk acute pulmonary embolism with minor RV dysfunction, minor myocardial necrosis, and no clinical worsening
• Acute gastrointestinal bleeding.
• Anticoagulation with international normalized ratio >1.8 or severe coagulopathy.
• Anaphylactic reaction to contrast media.
• Acute stroke.
• Acute renal failure or severe chronic non-dialysis dependent kidney disease.
• Uncooperative patient