non-ST Acute Myocardial Infarction Research Articles

P3122Complete versus culprit-vessel only revascularization for patients with acute coronary syndromes and multivessel disease

Abstract Background Recent randomized clinical trials have suggested that complete revascularization (CR) instead of culprit-vessel only revascularization (CVO) strategies may take a stand in the optimal management of patients admitted for acute myocardial infarction (AMI) with multivessel (MV) disease undergoing primary percutaneous coronary intervention (P-PCI). However, despite the 2017 ST-elevation acute coronary syndrome (STEMI) guidelines update with a new class of recommendation for CR, it remains controversial whether this strategy leads to better outcomes. Purpose To compare CR versus CV strategies during hospitalization in patients presenting with AMI with multivessel disease at P-PCI. Methods We analyzed data from all patients admitted with non-ST acute myocardial infarction (NSTEMI) and STEMI in a portuguese coronary care unit (CCU), between 2007 and 2016. We then evaluated potential differences of CR versus CVO with PCI during hospitalization in AMI patients with multivessel disease, defined by at least 2 different diseased main coronary vessels, saphenous vein or mammary artery conduits. We used 1:1 ratio propensity score matching to study the impact of CR on patient mortality and adjusted data for relevant risk factors at admission time. Results A total of 4758 patients were admitted for AMI, 2690 NSTEMI (56.5%) and 2068 STEMI (43.5%). Access to PCI records was possible in 3162 (66.5%) patients, of which 1707 (54%) underwent CR versus 1455 (46%) who underwent CVO. CVO patients were older (67.9±11.8 vs. 63.5±13.1 years, p<0.001), more diabetic (56.5% vs. 47.1%, p<0.001), hypertensive (78.4% vs. 72.2%, p<0.001), dyslipidemic (82.1% vs. 75%, p<0.001), had greater GRACE score at admission (mean score 143.4±37.2 vs. 131.2±131.2, p<0.001), had more severe coronary disease (mean number of diseased vessels – 2.56±0.6 vs. 2.18±0.4, p<0.004), reached higher Killip class (mean – 1.42±0.9 vs. 1.26±0.7, p<0.001) and had lower left ventricular ejection fraction (48.07±11.6 vs. 51.25±10.5, p<0.001). No significant differences were found in peak troponin-I release between CR and CV (44.7±69 vs. 46.9±76, respectively, p=0.468). After propensity matching, we obtained 130 CR and 133 CVO patients. In this cohort all-cause mortality was lower in CR group at 6-month (RR 0.262, CI 95% 0.071–0.962, p=0.031) and 1-year (RR 0.340, CI 95% 0.119–0.973, p=0.036) follow-up. When comparing STEMI versus NSTEMI all-cause mortality was nonsignificantly lower in CR (RR 0.394 vs. 0.226, p=0.12 vs. p=0.16). Conclusions In patients presenting with AMI and MV disease, CR strategy during hospitalization leads to greater 6-month and 1-year survival when compared with CVO strategy. Despite not having found significant differences when STEMI was directly compared to NSTEMI, we believe this was due to the great loss of patient numbers after propensity matching, requiring larger trials to prove the effect.

Does early coronary artery bypass surgery improve survival in non-ST acute myocardial infarction?

A best evidence topic was written according to a structured protocol. Lack of evidence exists regarding the optimal timing for coronary artery bypass graft (CABG) surgery after non-ST myocardial infarction (NSTEMI). While some authors address the importance of the timing of surgery alone, others take into account the extent of myocardial damage. The question addressed was whether early or late CABG surgery improves hospital mortality and cardiovascular events after NSTEMI in stable patients. Using a designated search strategy, 459 articles were found, of which seven represented the best available evidence. All of these studies were level 3 (retrospective cohort studies). Studies could be divided into those which assessed CABG outcome based on preoperative cardiac troponin I (cTnI) level as a measure of the extent of myocardial damage and those which considered only the timing after myocardial infarction. Outcome measures included short-term survival, hospital mortality, length of hospital stay and major adverse cardiovascular events (MACEs). The biggest retrospective study analysing postoperative outcomes based on the timing of surgery after NSTEMI concluded that operative mortality is higher when surgery is performed within 6 h of the event. After 6 h, mortality is similar at any timepoint after 6h of NSTEMI. While other smaller studies agree that there are fewer postoperative complications when surgery is performed after 48 h of the event, no consensus is found regarding mortality between early (less than 48 h) and late CABG surgery. Taking into account preoperative cTnI values, CABG has a higher incidence of MACEs and hospital mortality in patients with cTnI >0.15 ng/ml. When surgery is performed within 24 h of symptoms, preoperative cTnI >0.72 ng/ml is associated with worse outcomes. In view of the methodological limitations and level of evidence of the studies included, it appears that surgery may be safely performed in NSTEMI patients at any time after the first 6 h of the event in patients with cTnI <0.15 ng/ml, whereas in those patients with higher values of cTnI, waiting for cTnI to reduce before considering surgery seems to be a wise option in order to decrease the incidence of MACEs and hospital mortality.