Ultrasound‑enhanced, catheter‑directed thrombolysis for pulmonary embolism

Overall mortality at 3‑month follow‑up was 4% (7 out of 197) in a pooled analysis of ultrasound‑enhanced, catheter‑directed thrombolysis (UE‑CDT), in a systematic review of 7 studies with 197 patients. Deaths were mainly in patients with a massive pulmonary embolism (PE) and were caused by multi‑organ failure (n=1), discontinued treatment (n=1), acute abdominal haemorrhage with hypovolaemic shock 6 days after treatment (n=1), ovarian cancer and multiple factors (n=1), cardiogenic shock (n=1) and recurrent PE (n=1). Reasons for the other death were not given.

Mortality was 9% (1 out of 11) in the UE‑CDT group and 14% (2 out of 14) in the catheter‑directed thrombolysis (CDT) alone group in a retrospective comparative case series of 25 patients. One patient in the UE‑CDT group who had a massive PE died of multi‑organ failure 7 hours after treatment. One patient in the CDT group died of cardiac arrest and acidosis 2 hours after treatment, and 1 had severe heart failure and died 13 hours after treatment.

Acute kidney injury and cardiac arrest were reported in 1 patient (in whom a retracted infusion catheter was replaced and thrombolysis was extended) in a case series of 60 patients, in the systematic review of 7 studies. The patient was successfully resuscitated and recovered after lengthy hospitalisation.

Major bleeding complications were reported in 4% (7 out of 197) of the patients in a pooled analysis of UE‑CDT, in the systematic review of 7 studies. These included: bleeding from the access site that needed a blood transfusion (n=4), intra‑abdominal haemorrhage (n=1), intra‑thoracic bleeding after cardiopulmonary resuscitation that needed a blood transfusion (n=1) and intrapulmonary bleeding that needed a lobectomy (n=1).

Minor bleeding complications were reported in 11% (21 out of 197) of the patients in a pooled analysis of UE‑CDT, in the systematic review of 7 studies. These included: puncture site haematomas that needed no intervention (n=6) and non‑fatal haemoptysis (n=3). Details of the other 11 patients were not available.

In addition to safety outcomes reported in the literature, specialist advisers are asked about anecdotal adverse events (events which they have heard about) and about theoretical adverse events (events which they think might possibly occur, even if they have never done so). For this procedure, specialist advisers considered that the following were theoretical adverse events: distal embolisation, pulmonary artery perforation, extracranial haemorrhage, cerebrovascular accident, cardiac dysrhythmias and right ventricle failure.