This meta-analysis included 5 RCTs involving 528 patients with AMI undergoing DCB alone or stent implantation. The results indicated that DCB had no significant difference in MACE, cardiac death, MI, and TLR for AMI compared to stents, whereas LLL was smaller in the DCB group. We performed a subgroup analysis and observed that among STEMI patients, the incidence of MACE in the DCB group was similar to that in the stent group. Thus, these data indicated that DCB could provide a promising route for AMI.
In recent years, more and more studies have been conducted on DCB. In the treatment of RSI, meta-analysis of 10 RCTs from the DAEDALUS study showed that the composite incidence of all-cause death, MI, or target lesion thrombosis was similar for DCB treatment with compared to placement of a new stent, but re-stenting by DES was moderately higher. effective than DCB angioplasty in reducing the need for TLR at 3 years15. In a meta-analysis for the treatment of small vessel disease, application of DCB was associated with comparable outcomes of MACE versus DES16. Similarly, in patients with de novo coronary lesions, the use of DCB is associated with comparable clinical outcomes, such as TLR, compared to DES.17. DCB has demonstrated its safety and efficacy in the treatment of various types of coronary lesions and has sparked reflection on its use in AMI.
AMI is a common cardiac emergency that can lead to serious morbidity and mortality. The management of the AMI has improved considerably over the past three decades and is evolving18. Unlike treating older AMI patients, the increased prevalence of AMI in younger people has forced us to pay attention to long-term risks after stent placement, such as lifelong medications, bleeding, etc19. DCB can locally deliver antiproliferative drugs without a metal carrier, thereby directly inhibiting the process of endothelial proliferation and negative remodeling. The advantages of DCB dilation treatment over DES implantation include a lower incidence of restenosis, a shorter DAPT time to reduce the risk of bleeding, and the ability to promote further recovery of endothelial function without leaving metallic material behind. in the vessels.20.
In this study, lower LLL and even significant lumen enlargement were found in the DCB group. This suggests that DCB can lead to positive coronary remodeling. Positive remodeling after DCB in de novo lesions has also been reported by several studies21,22,23. The exact mechanism of late lumen enlargement is currently unknown and may be related to the long-term antiproliferative effects of drugs such as paclitaxel. Of course, determination of lumen diameter in studies is primarily based on coronary angiography findings, and more detailed and accurate assessment of lumen size and plaque regression by intraluminal imaging such as intravascular ultrasound or optical coherence tomography is needed in the future.21. To further confirm this finding, longer follow-up observations are needed.
DCB, as an attractive “leave nothing behind” strategy, can be safe and effective for the treatment of AMI. From another point of view, it is advisable to be cautious on the salvage rate of stents ranging from 5.7% to 18%. This is often due to inadequate predilation of the lesion, leading to elastic retraction or severe dissection of the vessel wall after DCB angioplasty, which necessitates the use of stents. It should be emphasized that the use of DCB for AMI is based on the safe and effective predilation of the culprit lesion. To get the most benefit from DCB, adequate predilation, especially in calcified lesions, is essential to maximize the contact area between the balloon and the vessel wall.24.
Coronary calcification is an important factor affecting the prognosis of patients with coronary artery disease, and the occurrence of calcifications is linked to factors such as advanced age, chronic kidney disease and diabetes.25.26. Severe calcification results in decreased rate of stent expansion, more likely to trigger ISR and TLR, and is associated with MACE26,27,28. Strategies for treating calcified lesions require special attention. Data on the treatment of calcified lesions were lacking in the studies included in this meta-analysis. Devices such as cutting and scoring balloons, rotational atherectomy, laser coronary atherectomy are used for the treatment of severe calcified lesions, and the study also showed that there was no significant difference in MACE over 1 year between DCB and DES after rotational atherectomy29. However, rotational atherectomy and laser coronary atherectomy may result in increased operative time. It may be more reasonable to pretreat the lesion with a common balloon or a cutting and incising balloon to achieve coronary reperfusion in a short time in patients with MI26. The treatment strategy for MI complicated by calcified lesions needs further study.
Additionally, the RCTs included in this review indicated that thrombus aspiration was performed on lesions with a high thrombotic load. Although routine thrombus aspiration did not affect mortality in trials30the researchers noted that optimizing lesion preparation was of great value in improving the consistent delivery of antiproliferative drugs8.
In general, adequate lesion preparation, including thrombus aspiration and adequate balloon dilation, is essential for DCB or stent therapy. For lesions with less than 30% residual stenosis or type A or B dissection, DCB or DES can be used. DCB may be beneficial for younger patients with STEMI or those at increased risk of bleeding and in cases of DAPT intolerance. Placement of a salvage stent was advised in case of residual stenosis of the treated lesion > 50% after dilatations with sufficiently large balloons, or coronary dissection greater than or equal to type C leading to closure of the vessel8.
Our meta-analysis has several limitations. First, the duration of follow-up for the five included studies was 6 to 12 months. The shorter follow-up time does not provide a good indication of the benefits of a DCB strategy that does not require long-term antiplatelet therapy, nor does it demonstrate its long-term safety. Although the results of the 5-year follow-up study demonstrated the safety of DCB for the treatment of de novo coronary artery disease, the long-term efficacy of DCB for AMI needs further investigation.31.
Second, the sample size may be too small. However, we performed a very comprehensive literature search to include all articles that met the criteria. On the other hand, our study may also provide theoretical support for more researchers to conduct such studies in the future.
Third, we observed heterogeneity in LLL statistics. According to the study design, we adopted a random-effects model to estimate the effect rather than a fixed-effects model because the earlier measures provided more conservative results.32. The same result was obtained after sensitivity analysis.
Overall, this is the first meta-analysis of RCTs comparing DCB angioplasty with stenting for AMI, which may provide new insights and insights for some interventional operators to treat AMI in the future, promote the development of interventional techniques and improve the long-term prognosis of AMI patients. Further extensive research is expected to support our findings.