Thrombolysis ‘not supported’ in PE
MedWire News: Thrombolysis does not significantly decrease the risk for death among hypotensive patients with pulmonary embolism (PE) and may increase mortality in those with normal blood pressure (BP), shows an analysis of RIETE registry data.
"The results of our study do not support the use of thrombolytic agents in most patients with acute symptomatic PE," remark David Jiménez (Ramón y Cajal Hospital, Madrid, Spain) and colleagues in the Journal of Thrombosis and Haemostasis.
The researchers explain that while the primary therapy for patients with PE is anticoagulation, thrombolysis may also be used even though its efficacy remains unclear.
Given this uncertainty, Jiménez and team retrospectively reviewed data from the RIETE registry (Registro Informatizado de la Enfermedad TromboEmbólica) to assess the association between thrombolytic therapy and all-cause mortality during the first 3 months after the diagnosis of PE.
They stratified the 15,944 patients with objectively confirmed PE into those with hypotension (systolic BP <100 mmHg) and those without it. They then used propensity score-matching to compare patients who received thrombolysis with those who did not in each BP subgroup.
Patients were matched for variables including age at time of PE diagnosis, recent (<30 days) major bleeding, PE risk factors, clinical signs and symptoms on admission, and abnormal serum creatinine levels (>2 mg/dL).
The researchers report that patients who received thrombolysis (n=432) were younger, had fewer comorbid diseases, and more severe clinical signs compared with those who did not receive it.
Overall mortality was 12% among the patients who received thrombolysis and 10% among those who did not, a nonsignificant difference.
In the subgroup of patients with systolic hypotension, analysis of propensity score-matched pairs (n=94 pairs) showed a statistically nonsignificant but clinically relevant lower risk for death among patients who received thrombolysis compared with those who did not, at an odds ratio (OR) of 0.72.
By contrast, normotensive patients who received thrombolysis had a significant 2.32-fold increased odds for death compared with those who did not when the team analyzed 217 propensity score-matched pairs.
However, this increased risk for death was attenuated in a sensitivity analysis in which the researchers imputed data for missing values for echocardiography and troponin tests. In this analysis, thrombolytic therapy did not show a significant positive or negative effect on survival.
Jiménez et al say that their findings are consistent with the position of the American College of Chest Physicians' guideline on antithrombotic therapy, which issued a weak recommendation for administrating thrombolysis to patients with PE and hypotension due to the uncertainty of the benefit.
"Results of the sensitivity analysis with imputed data suggest that improved methods of risk stratification and additional randomized controlled trials might help to identify subgroups of patients at high risk of death that might have a favorable risk to benefit ratio for treatment with systemic thrombolysis," the team concludes.
By Laura Cowen