If you don't remember your password, you can reset it by entering your email address and clicking the Reset Password button. You will then receive an email that contains a secure link for resetting your password
If the address matches a valid account an email will be sent to __email__ with instructions for resetting your password
demonstrating an association between inferior vena cava (IVC) filter placement and improved survival in stable patients with pulmonary embolism who received thrombolytic therapy. This study seems to be a case–control study, as summarized by the 2 × 2 table in the Figure.
FigurePutative 2 × 2 table design for Stein et al.
In clinical practice, thrombolysis is a more timely intervention and thus generally performed before IVC filter placement; patients who survive the initial course of acute pulmonary embolism are more likely to undergo IVC filter placement. Other confounders could include access to timely interventional radiology services and payer mix, which may be markers of hospital quality or the socioeconomic status of its patients. In addition, the authors do not provide details on how unstable patients were excluded from this study; defining these variables would strengthen their approach.
; and their decision to report absolute risk reduction and numbers needed to treat—which are generally reserved for prospective randomized trials—are misleading.
The authors also have not recognized threats to external validity, namely other robust population-level data suggesting IVC filters confer no survival benefit in patients who can receive anticoagulation.
Effect of a retrievable inferior vena cava filter plus anticoagulation vs anticoagulation alone on risk of recurrent pulmonary embolism: a randomized clinical trial.
have failed to demonstrate a mortality benefit in stable patients with acute pulmonary embolism. Why would combining these therapies be expected to protect against mortality in stable patients?
The conclusion that “an inferior vena cava filter results in a lower in-hospital all-cause mortality” in this population
would be overstated for any retrospective case–control study; we can only infer an association. Taken in the context of potential confounders and the broader literature on the treatment of acute pulmonary embolism, the authors should temper their enthusiasm.
References
Stein P.D.
Matta F.
Hughes M.J.
Inferior vena cava filters in stable patients with acute pulmonary embolism who receive thrombolytic therapy.
Effect of a retrievable inferior vena cava filter plus anticoagulation vs anticoagulation alone on risk of recurrent pulmonary embolism: a randomized clinical trial.
30111-6&id=ajm14522-fig-0001.jpg){kind=link}