Unsolved issues in the treatment of pulmonary embolism

The role of eustachian valve and patent foramen ovale in sudden death

Sudden unexpected cardiac death is the leading cause of death in industrialized countries. Patent foramen ovale and eustachian valve are two of cardiac diseases and they may be associated with clinical disorders as embolism, stroke, plathypnea-orthodeoxia syndrome, carcinoid heart disease, atrial flutter and endocarditis. The literature for the roles of patent foramen ovale and eustachian valve in the causes of sudden deaths are reviewed.

Paradoxical peripheral embolism coincident with acute pulmonary thromboembolism

Paradoxical embolism may occur in patients with acute pulmonary thromboembolism, when patent foramen ovale (PFO) coexists with pulmonary hypertension (right-left shunt). There have been few case reports of paradoxical embolism in peripheral arteries coincident with acute pulmonary thromboembolism. Here, we describe a case of paradoxical peripheral embolism associated with PFO complicated by acute pulmonary thromboembolism. The patient had severe peripheral ischemia due to a massive thrombus and was treated successfully by peripheral thrombectomy, thrombolysis, implantation of a permanent inferior vena cava filter and anticoagulation.

Current perspectives on the treatment of venous thromboembolism: need for effective, safe and convenient new antithrombotic drugs

Treatment of venous thromboembolism (VTE) has evolved significantly over the last decade. Low-molecular-weight heparins have largely replaced unfractionated heparin in the treatment of deep-vein thrombosis (DVT) but the majority of patients with pulmonary embolism (PE) continue to be treated with unfractionated heparin. Fondaparinux is the first synthetic selective inhibitor of factor Xa. It has recently been proved to be more effective than, and as safe as, a low-molecular-weight heparin for the prevention of VTE after major orthopaedic surgery. The two large randomised MATISSE trials demonstrated that fondaparinux was at least as effective and as safe as previous reference heparin therapies in the treatment of VTE. Fondaparinux should further simplify the treatment of this frequent disease since a single once-daily fixed dosage regimen may effectively and safely treat both DVT and PE, an important point especially considering the frequent though clinically silent concomitance of these two thrombotic events.

Local and systemic thrombolytic therapy for acute venous thromboembolism

Thrombolytic therapy unquestionably leads to more rapid and complete clot lysis with a significantly higher risk of bleeding when compared with anticoagulation. The most definite indication for thrombolytic therapy in patients with VTE is massive PE associated with hemodynamic instability. Other potential indications, although not widely accepted or proven, include PE-related respiratory failure with severe hypoxemia and massive iliofemoral thrombosis with the risk of phlegmasia cerulea dolens. Routine use of thrombolytic therapy in all other cases of PE and DVT cannot be justified. Future research using randomized controlled studies should focus on the following key questions: Do hemodynamically stable patients with PE and right ventricular dysfunction benefit from thrombolysis, and, if so, is there a subset of patients within this group who are most likely to benefit? Does thrombolytic therapy improve long-term outcomes of DVT with a favorable risk-to-benefit ratio, and, if so, which patients are most likely to benefit long-term? What is the precise role of catheter-directed thrombolysis in the treatment of VTE, particularly the use of a low-dose thrombolytic agent in conjunction with mechanical clot disruption to minimize bleeding in patients at high risk? Until these questions are answered, clinicians must approach decision-making regarding the use of thrombolytic therapy in PE and DVT with careful consideration of the potential risks and benefits for the patient within the framework of currently available data.

Temporary IVC filtration before patent foramen ovale closure in a patient with paradoxic embolism

Pulmonary embolism (PE) and associated acute peripheral ischemia suggest the diagnosis of paradoxic embolism. The most common intracardiac defect associated with paradoxic emboli is a patent foramen ovale (PFO). Therapeutic options include anticoagulation, thrombolysis, inferior vena cava (IVC) filtration, and closure of the intracardiac defect. The authors discuss the diagnosis and treatment of a young female athlete who presented with massive PE complicated by a paradoxic embolus to the right subclavian artery. Systemic and catheter-directed thrombolysis, IVC filtration, and percutaneous closure of a PFO were performed in an effort to return the patient to the level of competitiveness she desired.