Author + information
- Anne Kaltoft, MD, PhD⁎ (, )
- Henning Kelbæk, MD, DMSCi,
- Lene Kløvgaard, RN,
- Christian Juhl Terkelsen, MD, PhD,
- Peter Clemmensen, MD, DMSCi,
- Steffen Helqvist, MD, DMSCi,
- Jens Flensted Lassen, MD, PhD and
- Leif Thuesen, MD, DMSCi
- ↵⁎Department of Cardiology B, Aarhus University Hospital, Skejby, 8200 Aarhus N, Denmark
We appreciate the interest of Dr. West and colleagues in our 15-month follow-up of the DEDICATION (Drug Elution and Distal Protection in Acute Myocardial Infarction) trial (1).
In the DEDICATION trial, ST-segment elevation myocardial infarction patients were randomized to distal protection (DP) with an embolic protection device or standard percutaneous coronary intervention (PCI). For distal protection, we used the FilterWire EZ device in 215 (68%) patients and the SpiderX device in 39 (13%); in 58 patients (19%), none of the protection devices could be inserted in the vessel.
Dr. West and colleagues correctly point to the fact that the FilterWire EZ device previously was available in only 1 size designed for vessels with reference diameters between 3.5 and 5.5 mm with a recommended minimum diameter of the landing zone of ≥3 mm. We used this device in the DEDICATION trial. After the DEDICATION trial ended in May 2008, Boston Scientific launched a FilterWire designed for vessels with diameters between 2.25 and 3.5 mm (2).
In the DEDICATION trial, the median reference vessel diameter was 3.5 mm (interquartile range 3.0 to 3.7 mm), and the diameter was 3.4 ± 0.49 mm. In the DP group, 21 patients had a reference vessel diameter <3.0 mm. Of these, 2 patients did not have a filter inserted, 6 patients were treated with the SpiderX device, and 13 patients were treated with the FilterWire EZ. In these 13 patients, we saw 3 stent thromboses/target lesions. Further analysis of the differences in major adverse cardiac event (MACE) rates in patients receiving the different types of devices would be informative. However, as small vessels may be associated with diabetes, older age, female sex, and so on, and therefore a risk factor for MACE, a multivariate analysis must be performed to properly elucidate this issue. Unfortunately, the number of patients in these groups and the MACE rate in this rather short time frame are too low to permit further analysis. We expect to perform such an analysis when a longer follow-up period has been reached and/or our findings can be pooled with data from similar studies.
We do acknowledge that appropriate DP device sizing may be an issue in these treatments. However, the use of smaller DP devices in our study would not have changed the overall results. Further, as Dr. West and colleagues also highlight, even when appropriately sized, the FilterWire EZ has been demonstrated to cause histological evidence of substantial intimal disruption (3), and as neither the DEDICATION trial nor any other randomized trial has demonstrated the benefit of filter protection during primary PCI, we still find that routine use of filter protection during primary PCI cannot be advocated.
- American College of Cardiology Foundation
- Kaltoft A.,
- Kelbæk H.,
- Klovgaard L.,
- et al.
- Boston Scientific