Acute Coronary Syndrome With Unprotected Left Main Coronary Artery Culprit - An Observation From the AOI-LMCA Registry

Early and Long-Term Outcomes of Patients With Acute Coronary Syndrome Undergoing Percutaneous Coronary Intervention to the Left Main Coronary Artery

Patients who undergo percutaneous coronary intervention (PCI) to the left main (LM) coronary artery in the setting of acute coronary syndrome (ACS) were not adequately studied in the era of modern PCI. We investigated early and long-term outcomes of these patients, especially those with a true LM bifurcation stenosis. The Left Main Intervention in Acute Coronary Syndrome (LIMACS) is a multicenter registry that enrolled patients who underwent PCI to unprotected LM disease in the setting of ACS using a drug-eluting stent. The study included 360 patients (age 65 ± 12 years, men 74%, ST-elevation myocardial infarction 65%). During index hospitalization, 25% of patients developed cardiogenic shock and 15% died. Cardiogenic shock (adjusted odds ratio [adjOR] 26, 95% confidence interval [CI] 7 to 93) and final Thrombolysis in Myocardial Infarction (TIMI) grade <3 flow (adjOR 7, 95% CI 1.6 to 31) were associated with in-hospital mortality. The 3-year mortality (37%) correlated with left ventricular ejection fraction ≤40% (adjHR 2.4 [1.4 to 4.2]), Killip class II to IV at presentation (adjHR 1.7 [1.02 to 2.8]), LM culprit (adjHR 1.7 [1.04 to 2.8]), true LM bifurcation stenosis (adjHR 1.8[1.1 to 2.9]), final TIMI grade <3 flow (adjHR 3.2 [1.7 to 5.8]), and radial access (adjHR 0.58 [0.38 to 0.99]). In patients with true LM bifurcation stenosis (n = 127), 2-stent strategy was adopted in 60% and was associated with lower 3-year mortality or repeat revascularization than 1-stent strategy (48% vs 69%, p = 0.012). In conclusion, patients who undergo PCI to the LM in the setting of an ACS sustain high adverse event rates. Hemodynamic status, LM culprit lesion, femoral access, and failure to restore normal flow are major determinants of adverse outcomes. In patients with LM true bifurcation lesions, outcomes are impaired, especially with 1-stent strategy.

Impact of right coronary artery dominance on the long-term mortality in the patients with acute total/subtotal occlusion of unprotected left main coronary artery

BACKGROUND

Patients with a right dominant coronary artery anatomy account for a significant proportion of acute myocardial infarction cases, and this condition is associated with a better prognosis. However, there are limited data on the impact of coronary dominance on patients with acute total/subtotal occlusion of unprotected left main coronary artery (ULMCA).

METHODS

This study aimed to assess the impact of right coronary artery (RCA) dominance on long-term mortality in patients with acute total/subtotal occlusion of the ULMCA. From a multicenter registry, 132 cases of consecutive patients who had undergone emergent percutaneous coronary intervention (PCI) due to acute total/subtotal occlusion of the ULMCA were reviewed.

RESULTS

Patients were classified into two groups according to the size of their RCA (dominant RCA group, n = 29; non-dominant RCA group, n = 103). Long-term outcomes were examined according to the presence of dominant RCA. Cardiopulmonary arrest (CPA) occurred in 52.3 % of patients before revascularization. All-cause death was significantly lower in the dominant RCA group than in the non-dominant RCA group. In the Cox regression model, dominant RCA was an independent predictor of all-cause death, as well as total occlusion of ULMCA, collateral from RCA, chronic kidney disease, and CPA. Patients were further analyzed according to the degree of stenosis of the ULMCA; patients with non-dominant RCA and total occlusive ULMCA had the worst outcome compared with the other groups.

CONCLUSIONS

A dominant RCA might improve long-term mortality in patients with acute total/subtotal occlusion of the ULMCA who were treated with PCI.

Percutaneous Treatment of Left Main Disease: A Review of Current Status

Percutaneous treatment of the left main coronary artery is one of the most challenging scenarios in interventional cardiology, due to the large portion of myocardium at risk the technical complexity of treating a complex bifurcation with large branches. Our aim is to provide un updated overview of the current indications for percutaneous treatment of the left main, the different techniques and the rationale underlying the choice for provisional versus upfront two-stent strategies, intravascular imaging and physiology guidance in the management of left main disease, and the role of mechanical support devices in complex high-risk PCI.

Clinical and electrocardiographic features in acute total left main coronary artery occlusion without collateral circulation

BACKGROUNDS

Study concerning the clinical features, electrocardiogram (ECG) findings and outcomes in patients presenting with acute total occlusion of left main coronary artery (LM) without collateral circulation is limited.

METHODS

25 patients with acute total LM occlusion without collateral circulation by emergency coronary angiography, from muti-center registry, were retrospectively studied. The clinical and angiographic characteristics, ECG and in-hospital mortality were reviewed.

RESULTS

Nineteen patients (76%) presented with cardiogenic shock. Twelve (60%, 12/20) patients had coronary slow flow or no reflow phenomenon after primary percutaneous coronary intervention (PCI). The in-hospital mortality rate was 88% (n = 22). All the patients presented with ST-segment elevation myocardial ischemia (STEMI) pattern, mostly involving leads I, aVL, V2, V3, V4, V5 and ST-segment depression in leads II, III and aVF.

CONCLUSIONS

Acute total LM occlusion without collateral circulation portends high in-hospital mortality. Anterior ST elevation in the precordial leads from V2 to V4 through V6, and ST elevation in leads I and aVL, accompanying with ST depression in the inferior leads is associated with acute total LM occlusion without collateral circulation.

Prognosis of cardiogenic shock secondary to culprit left main coronary artery lesion-related myocardial infarction

AIMS

This study aimed to assess, in patients with cardiogenic shock secondary to unprotected left main coronary artery-related myocardial infarction (ULMCA-related AMICS), the incidence and predictors of no recovery of left ventricular function during the admission.

METHODS AND RESULTS

This was an observational study conducted at two tertiary care centres (2012-20). The main outcome measured was death or requirement for heart transplantation (HT) or left ventricular assist devices (LVAD) during the admission. A total of 70 patients were included. Percutaneous coronary intervention (PCI) was successful in 53/70 patients (75.7%). The combined endpoint of death or requirement of HT or LVAD during the admission occurred in 41/70 patients (58.6%). The highest incidence of the primary endpoint was observed among patients with profound shock and occluded left main coronary artery (LMCA) (20/23, 87%, P < 0.001). Although a successful PCI reduced the incidence of the event in the whole cohort (51.9% vs. 82.4% in failed PCI, P = 0.026), this association was not observed among this last group of complex patients (86.7% vs. 87.5% in failed PCI, P = 0.731). The predictive model included left ventricular ejection fraction, baseline ULMCA Thrombolysis In Myocardial Infarction flow, and severity of shock and showed an optimal ability for predicting death or requirements for HT or LVAD during the admission (area under the curve 0.865, P < 0.001).

CONCLUSIONS

ULMCA-related AMICS was associated with a high in-hospital mortality or need for HT or LVAD. Prognosis was especially poor among patients with profound shock and baseline occluded LMCA, with a low probability of recovery regardless of successful PCI.

Electrocardiographic patterns predict the presence of collateral circulation and in-hospital mortality in acute total left main occlusion

Background

Data on the clinical characteristics, electrocardiogram (ECG) findings and outcomes of patients with acute myocardial infarction (AMI) due to total unprotected left main (ULM) artery occlusion is limited.

Methods

Between 2009 and 2021, 44 patients with AMI due to total ULM occlusion underwent primary percutaneous coronary intervention (PCI) at our institution. The ECG, collateral circulation, clinical and procedural characteristics, and in-hospital mortality were retrospectively evaluated.

Results

Twenty five patients presented with shock and 18 patients had in-hospital mortality. Nineteen patients presented with ST-segment elevation myocardial infarction (STEMI), while 25 presented with non-ST-segment elevation myocardial infarction (NSTEMI). ST-segment elevation (STE) in I and STEMI were associated with the absence of collateral circulation, while STE in aVR was associated with its presence. In the NSTEMI group, patients with STE in both aVR and aVL showed more collateral filling of the left anterior descending coronary artery (LAD) territory, while patients with STE in aVR showed more collateral filling of the LAD and the left circumflex artery territory. Compared with total ULM occlusion, patients with partial ULM obstruction presented with more STE in aVR, less STE in aVR and aVL, and less STEMI. Shock, post-PCI TIMI 0–2 flow, non-STE in aVR, STEMI, and STE in I predicted in-hospital mortality. STEMI and the absence of collateral flow were significantly associated with shock.

Conclusions

STE in the precordial leads predicted the absence of collateral circulation while STE in aVR and STE in both aVR and aVL predicted different collateral filling territories in ULM occlusion. STE in I, non-STE in aVR, and STEMI predicted in-hospital mortality in these patients.

Clinical Outcomes Following Emergent Percutaneous Coronary Intervention for Acute Total/Subtotal Occlusion of the Left Main Coronary Artery

BACKGROUND

Data regarding the clinical features, outcomes and prognostic factors in patients presenting with acute total/subtotal occlusion of the unprotected left main coronary artery (LMCA) remain limited.

METHODS AND RESULTS

From a multi-center registry, 134 patients due to acute total/subtotal occlusion of the unprotected LMCA were reviewed. Emergency room (ER) status classification was defined according to the presence of cardiogenic shock and cardiopulmonary arrest (CPA) in the ER (class 1=no cardiogenic shock; class 2= cardiogenic shock but not CPA; and class 3=CPA). In-hospital mortality and cerebral performance category (CPC) as the endpoints were evaluated. One-half (67/134) of the enrolled patients presented with total occlusion of the unprotected LMCA. Regarding ER status classification, class 1, 2, and 3 were observed in 30.6%, 45.5%, and 23.9% of the patients, respectively. In-hospital mortality occurred in 73 (54.5%) patients; of the remaining patients, 52 (85.3%) could be discharged with a CPC 1 or 2. ER status classification (odds ratio 4.4 [95% confidence interval: 2.33-10.67]; P<0.001) and total occlusion of the unprotected LMCA (odds ratio 8.29 [95% confidence interval 2.93-23.46]; P<0.001) were strong predictors of in-hospital mortality.

CONCLUSIONS

Acute total/subtotal occlusion involving the unprotected LMCA appeared to be associated with high in-hospital mortality. ER status classification and initial flow in the unprotected LMCA were significant predictive factors of in-hospital mortality.

Usefulness of excimer laser in acute coronary syndrome with left main coronary artery: a case series

Background

Acute coronary syndrome caused by unprotected left main coronary artery (ACS-ULMCA) occlusion has a high mortality due to the formation of plaques and rich thrombi. Although excimer laser coronary angioplasty (ELCA) is effective in debulking and ablation of plaque burden and rich thrombi, its effectiveness in ACS-ULMCA remains unknown.

Case summary

We conducted percutaneous coronary intervention (PCI) using ELCA for six patients with ACS-ULMCA from February 2016 to May 2019. This case series includes a 65-year-old man who presented with sudden-onset chest pain. Angiography revealed subtotal occlusion of the left main coronary artery (LMCA). The use of a 0.9-mm ELCA catheter advanced from LMCA to the left anterior descending artery markedly improved coronary blood flow, and intravascular ultrasound revealed debulking of the plaque and thrombus. Another 79-year-old man presented with chest pain. Angiography revealed total occlusion of LMCA. Use of a 0.9-mm ELCA catheter improved coronary blood flow. Subsequent kissing balloon technique led to satisfactory results. All cases needed mechanical support (such as intra-aortic balloon pumping or percutaneous cardiopulmonary support) prior to PCI. Five patients survived finally, and one died 34 days after primary PCI.

Discussion

After stabilizing haemodynamics by mechanical support, ELCA could be a good option to improve coronary blood flow in patients with ACS-ULMCA.

Factors associated with left ventricular reverse remodelling after percutaneous coronary intervention in patients with left ventricular systolic dysfunction

Percutaneous coronary intervention (PCI) is sometimes considered as an alternative therapeutic strategy to surgical revascularization in patients with coronary artery disease (CAD) and reduced left ventricular ejection fraction (LVEF). However, the types or conditions of patients that receive the clinical benefit of left ventricular reverse remodelling (LVRR) remain unknown. The purpose of this study was to investigate the determinants of LVRR following PCI in CAD patients with reduced LVEF. From 4394 consecutive patients who underwent PCI, a total of 286 patients with reduced LV systolic function (LVEF < 50% at initial left ventriculography) were included in the analysis. LVRR was defined as LV end-systolic volume reduction ≥ 15% and improvement of LVEF ≥ 10% at 6 months follow-up left ventriculography. Patients were divided into LVRR (n = 63) and non-LVRR (n = 223) groups. Multivariate logistic regression analysis revealed that unprotected left main coronary artery (LMCA) intervention was significantly associated with LVRR (P = 0.007, odds ratios [OR] 4.70, 95% confidence interval [CI] 1.54-14.38), while prior PCI (P = 0.001, OR 0.35, 95% CI 0.19-0.66), presence of in-stent restenosis (P = 0.016, OR 0.32, 95% CI 0.12-0.81), and presence of de-novo stenosis (P = 0.038, OR 0.36, 95% CI 0.14-0.95) were negatively associated with LVRR. These data suggest the potential prognostic benefit of unprotected LMCA intervention for LVRR and importance of angiographic follow-up in patients with CAD and LV systolic dysfunction.

Clinical factors associated with slow flow in left main coronary artery-acute coronary syndrome without cardiogenic shock

Since slow flow can be a fatal complication in left main coronary artery (LMCA)-acute coronary syndrome (ACS) patients, it should be important to anticipate and prepare slow flow during primary PCI for LMCA-ACS. We hypothesized that intravascular ultrasound (IVUS) findings would be useful to predict slow flow for LMCA-ACS patients without cardiogenic shock (CS). The purpose of this study was to investigate clinical factors associated with slow flow in LMCA-ACS patients without CS. We included 60 LMCA-ACS patients without CS, and divided into the slow flow group (n = 18) and the non-slow flow group (n = 42). Slow flow was defined as either transient or persistent TIMI flow grade ≤ 2. The prevalence of ST-segment elevation myocardial infarction (STEMI) was significantly higher in the slow flow group (55.6%) than in the non-slow flow group (11.9%) (p = 0.002). In the IVUS analysis, remodeling index was significantly greater in the slow flow group (1.15 ± 0.17) than in the non-slow flow group (0.99 ± 0.11) (p = 0.001). The multivariate logistic regression analyses in the IVUS factors revealed that remodeling index was significantly associated with slow flow (0.1 increase: OR 2.238, 95% CI 1.144-4.379, p = 0.019). In conclusion, remodeling index was significantly associated with slow flow. Our results suggest that the remodeling index determined by IVUS would be useful to find high-risk features of slow flow in LMCA-ACS patients without CS.