But wait, look what's hot off the press: PEITHO study
The PEITHO (Pulmonary EmbolIsm THrOmbolysis) study data was just presented at the American College of Cardiology 2013 Scientific Sessions. This is the largest study looking at sub-massive PEs and use of thrombolytics, conducted over 10 years. In this study, sub-massive PE comprised about 15 to 20% of all PEs, and patients were at high risk for death and cardiovascular collapse.
This was a prospective, multicenter study of just over 1000 patients who were randomized to a FULL, weight-dosed bolus of tenecteplase plus heparin (treatment arm) versus just heparin alone (control arm). The primary endpoint evaluated was the combined endpoint of death from any cause and hemodynamic collapse at 7 days.
The relative risk reduction (RRR) of the primary endpoint was about 56%, but as we are always cautioned about RRR, the actual numbers show primary endpoint rates of 2.6% in the treatment arm and 5.6% in the control arm, which is an ARR of only 3%. Unfortunately, the rate of major bleeding was significantly higher in the treatment arm (6.3%) compared to the control arm (1.5%).
So are lytics in sub-massive PE ready for primetime?
My opinion is we are not there yet. Several studies now have shown the risk of major bleeding with lytics, but no real significant improvement in mortality. Let's see what else we have coming up in the pipeline in the near future. Remember our job as physicians is to do no harm, and right now the evidence says we are doing more harm than good with full-dose lytics in sub-massive PE.
Coincidentally, this article was also discussed at the 2013 Bay Area EM Residency Journal Club last night with UCSF-SFGH, Stanford-Kaiser, and Highland. See the Twitter discussion
[ View the story "MOPETT and PLEITHO studies on lytics and submassive PEs" on Storify ]
-- Salim R. Rezaie, MD (Twitter: @srrezaie )