| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
Letters |
University of Texas
Southwestern Medical Center
Dallas,
TX
Approximately 70% of the patients found at autopsy to have died of pulmonary embolic disease were not suspected to have emboli during their terminal course [1, 2].
Eyer et al. [3] reported that 10% of a group of patients whose CT pulmonary angiograms showed isolated subsegmental pulmonary emboli or whose scans were inconclusive and were not treated with anticoagulants died without clinical evidence of recurrent venous thromboembolism. I disagree with using this as evidence that the patients had not experienced emboli and that anticoagulation may safely be withheld in this setting.
References
Medical College of Wisconsin
Milwaukee, WI 53226-3596
We thank Dr. Landay for his interest. He is certainly correct that autopsies frequently show fatal pulmonary emboli that were unsuspected during life. Thus, he believes that pulmonary emboli cannot be excluded in the 10% of our patients who died. The lack of definitive autopsy proof of an absence of pulmonary embolus is understood to be a weakness of our study design [1]. Factors that my coauthors and I think support the conclusion that these patients did not have fatal pulmonary emboli include the fact that all had serious comorbid conditions that were understood by their clinicians to give an adequate explanation for the patients' mortality. Our patients had small pulmonary emboli or studies that failed to exclude small pulmonary emboli, and all had CT studies that showed no deep vein thrombosis. In addition, seven (4%) of 170 patients later had symptoms suggestive of pulmonary embolus, and none was subsequently proven to have pulmonary embolus.
The statistic that Landay quotes is that 70% of patients who die of pulmonary emboli were not suspected to have pulmonary emboli during life. The group of patients who undergo autopsy with no premorbid suspicion of pulmonary emboli is entirely different from our group of patients, those in whom pulmonary emboli were suspected during life. We know of no study that looks at a large autopsy population of patients similar to our patients, and this statistic is clearly not applicable to our patients.
As detailed in our Discussion, despite the extensive literature on pulmonary embolus, there is little direct evidence that treating small pulmonary emboli in patients with no evidence of deep vein thrombosis is beneficial. A number of indirect studies suggest withholding anticoagulation therapy in patients with good cardiopulmonary reserve, small or questionable emboli, and no evidence of deep vein thrombosis is not detrimental. There is no doubt that heparin or warfarin treatment is associated with significant mortality and morbidity, and the diagnosis of pulmonary embolus changes the patient's self-perception and the perception of the treating physician for the rest of the patient's life [2, 3]. Until a controlled study is performed in which 50% of the patients with pulmonary embolus receive anticoagulants and 50% do not, we will have to depend on indirect and circumstantial evidence.
MDCT frequently reveals small emboli in patients with suspected pulmonary emboli and shows unsuspected emboli in 3.4% of those being scanned for other reasons [4]. With improved imaging and the depiction of smaller and smaller clots, it is appropriate to start questioning whether every patient with a pulmonary embolus needs a full course of anticoagulation. The topic of small pulmonary emboli is discussed in greater detail in a recent editorial [5].
References
CiteULike 
Complore 
Connotea 
Del.icio.us 
Digg 
Reddit 
Technorati What's this?
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
