Post-angioplasty myocardial blush grade for long term prognostication in acute coronary syndrome: a systematic review and meta-analysis

Abstract

Abstract Background Reduced myocardial perfusion despite achieving adequate epicardial bloodflow after angioplasty has been reported to occur in up to 71–80% of Acute Coronary Syndrome (ACS) patients. This is associated with worsening myocardial function and has detrimentally affected long term survival of ACS patients. Myocardial Blush Grade (MBG) is an angiographic parameter of myocardial perfusion that has been found to correlate well with markers of post-infarction myocardial function. However, its acceptance as a reliable marker in routine clinical practice has not yet gained foothold. Purpose We aimed to determine the prognostic value of MBG for long term all-cause mortality and major adverse cardiovascular events (MACE) among acute coronary syndrome patients who underwent primary angioplasty. Methods PubMed, Google Scholar, Science Direct, and the Cochrane Central Registry were searched for relevant studies published from 1 January 1998 to 31 December 2020. The primary outcome was indexed all-cause mortality and the secondary outcome was major adverse cardiovascular event. A Mantel-Haenszel random effects meta-analysis was used to derive the pooled estimate of each outcome. Results Ten studies involving a total of 11,531 ACS patients were included. Results showed that MBG 0/1 with no to poor myocardial perfusion had a cumulative negative prognostic value for mortality (OR=2.71, CI: 2.11–3.49, p<0.ehab724.13141, I2=35%) and MACE (OR=1.28, CI: 1.03–1.58, p<0.02, I2=39%). Subgroup analysis showed MBG 0/1 had a significant negative prognostic association for mortality among ST-elevation myocardial infarction patients (OR=2.86, CI: 2.17–3.76, p<0.ehab724.13141, I2=44%) but did not have a significant association among unstable angina/Non-ST-elevation Myocardial Infarction patients (OR=1.68, CI: 0.76–3.71, p 0.20, I2=0%). Subsequently, MBG 3 with normal myocardial perfusion was associated with a reduced risk for long term all-cause mortality (HR=0.22, CI: 0.15 to 0.33, p 0.02, I2=39%). Conclusion Our results support the use of post-angioplasty Myocardial Blush Grade to prognosticate ST-elevation myocardial infarction patients. MBG 0/1 is a strong negative prognostic marker for long term all-cause mortality and major adverse cardiovascular events while an MBG 3 is a strong positive prognostic marker for long term survival. However, more data is still needed to determine its prognostic value for unstable angina and non-ST-elevation ACS patients. Funding Acknowledgement Type of funding sources: None. Figure 1. MBG 0/1 and all-cause mortalityFigure 2. MBG 3 and long term survival