Letter to the editor Systemic Thrombolysis for High-risk Pulmonary Embolism Versus Percutaneous Transcatheter Treatment

To the Editor,

Systemic thrombolysis for primary reperfusion therapy is the treatment of choice for patients with high-risk pulmonary embolism (PE) (ie, those with shock or hypotension). If thrombolysis is contraindicated or has failed, surgical embolectomy or percutaneous catheter-directed treatment is recommended. However, when systemic thrombolytic therapy is contraindicated, local administration is also contraindicated, in which case transcatheter procedures should be used without local thrombolysis.¹ Sánchez-Recalde et al² presented a series of 8 PE patients treated at their hospital. Seven patients underwent percutaneous treatment, of whom 4 also received local catheter-administered alteplase, although this approach is contraindicated for thrombolysis. According to the recommendations of the clinical guidelines, traumatic brain injury is an absolute contraindication and thus alteplase should not have been used. The patient with this injury died of intracranial hemorrhage. The other 3 patients who received local thrombolytic therapy were postoperative patients, but the authors did not specify how much time had passed since the surgery; this information is needed to consider the contraindication for thrombolytic therapy as absolute or relative. Six of the patients had cardiorespiratory arrest, but the authors did not indicate which patients had experienced this event. Torbicki³ has reported that there are very few contraindications to the use of thrombolysis in critical situations, including recent surgery, and that provision should be made to treat bleeding complications immediately. In the setting of cardiac arrest, the benefit of the rapid systemic administration of thrombolytics can be enhanced by the simultaneous treatment of venous thrombi, and the prevention of patient transfer to the catheterization laboratory and the potential complications of percutaneous procedures. The other hospital death described in their series was attributed to rethrombosis after suspension of anticoagulation therapy to repair a complication arising from the percutaneous procedure.

Currently, there is a lack of reliable studies on systemic thrombolysis vs catheter-directed thrombolysis for high- and intermediate-risk PE or on the effect of different catheter-directed percutaneous techniques on survival and bleeding complications.⁴ In the absence of reliable studies, it seems advisable to adhere to the recommendations of the clinical guidelines, which consider systemic thrombolysis the treatment of choice for high-risk PE unless absolutely contraindicated. It should be borne in mind that the guidelines state that if thrombolytic therapy is contraindicated, local administration is also contraindicated. Finally, recent surgery could be considered to be a relative contraindication for systemic thrombolysis only in immediate high-risk life-threatening PE and only if provision has been made for potential bleeding complications and their immediate treatment. In the latter setting, a reasonable strategy could be to use low-dose systemic alteplase (50 mg/2 h), which seems to have similar efficacy and lower bleeding risk than the approved standard systemic dose of 100 mg/2 h.⁵