Impact of coronary collaterals on in-hospital and 5-year mortality after ST-elevation myocardial infarction in the contemporary percutaneous coronary intervention era: a prospective observational study

Association between the pan-immune-inflammation value and coronary collateral circulation in chronic total coronary occlusive patients

BACKGROUND

Inflammation and immunity play important roles in the formation of coronary collateral circulation (CCC). The pan-immune-inflammation value (PIV) is a novel marker for evaluating systemic inflammation and immunity. The study aimed to investigate the association between the PIV and CCC formation in patients with chronic total occlusion (CTO).

METHODS

This retrospective study enrolled 1150 patients who were diagnosed with CTO through coronary angiographic (CAG) examinations from January 2013 to December 2021 in China. The Cohen-Rentrop criteria were used to catagorize CCC formation: good CCC formation (Rentrop grade 2-3) and poor CCC formation group (Rentrop grade 0-1). Based on the tertiles of the PIV, all patients were classified into three groups as follows: P1 group, PIV ≤ 237.56; P2 group, 237.56< PIV ≤ 575.18; and P3 group, PIV > 575.18.

RESULTS

A significant relationship between the PIV and the formation of CCC was observed in our study. Utilizing multivariate logistic regression and adjusting for confounding factors, the PIV emerged as an independent risk factor for poor CCC formation. Notably, the restricted cubic splines revealed a dose-response relationship between the PIV and risk of poor CCC formation. In terms of predictive accuracy, the area under the ROC curve (AUC) for PIV in anticipating poor CCC formation was 0.618 (95% CI: 0.584-0.651, P < 0.001). Furthermore, the net reclassification index (NRI) and integrated discrimination index (IDI) for PIV, concerning the prediction of poor CCC formation, were found to be 0.272 (95% CI: 0.142-0.352, P < 0.001) and 0.051 (95% CI: 0.037-0.065, P < 0.001), respectively. It's noteworthy that both the NRI and IDI values were higher for PIV compared to other inflammatory biomarkers, suggesting its superiority in predictive capacity.

CONCLUSIONS

PIV was associated with the formation of CCC. Notably, PIV exhibited potential as a predictor for poor CCC formation and showcased superior predictive performance compared to other complete blood count-based inflammatory biomarkers.

Association of collateral flow with clinical outcomes in patients with acute myocardial infarction

Coronary collateral flow is an important prognostic marker in percutaneous coronary intervention (PCI) for chronic total occlusion. However, the role of collateral flow to the culprit lesion of acute myocardial infarction (AMI) has not been fully established yet. The purpose of this retrospective study was to examine the association between collateral flow and long-term clinical outcomes in patients with AMI. We included 937 patients with AMI, and divided those into the no-collateral group (n = 704) and the collateral group (n = 233) according to the presence or absence of collateral flow to the culprit lesion of AMI. The primary endpoint was the incidence of major adverse cardiac events (MACE), which was defined as a composite of all-cause death, non-fatal MI, re-admission for heart failure, and ischemia driven target vessel revascularization. The median follow-up duration was 473 days (Q1: 184 days- Q3: 1027 days), and a total of 263 MACE was observed during the study period. The incidence of MACE was significantly greater in the no-collateral group than in the collateral group (29.8% vs. 22.3%, p = 0.027). In the multivariate COX hazard model, the presence of collateral flow was inversely associated with MACE (HR 0.636, 95% CI 0.461-0.878, p = 0.006) after controlling multiple confounding factors. In conclusion, the presence of collateral flow to the culprit lesion of AMI was inversely associated with long-term adverse outcomes. Careful observation of collateral flow may be important in emergent coronary angiography to stratify a high-risk group among various patients with AMI.

The predictive value of the triglyceride-glucose index for cardiovascular events in patients with coronary chronic total occlusion

BACKGROUND

Chronic total occlusion (CTO) of the coronary artery is a difficult problem in clinical practice. The triglyceride-glucose (TyG) index is an effective risk predictor of cardiovascular risk. However, the relationship between the TyG index and the prognosis of CTO patients remains unstudied. Thus, the present study aimed to investigate the relationship between the TyG index and cardiovascular risk in CTO patients.

METHODS

This was a single-centre, retrospective cohort study. We retrospectively enrolled 652 patients with CTO lesions diagnosed by angiography and who underwent revascularization through PCI. Patients were routinely followed up for 24 months unless meeting the endpoint. The primary endpoint was the composite of all-cause death, nonfatal myocardial infarction, unplanned revascularization, and nonfatal ischaemic stroke. To test the association of the TyG index with cardiovascular risk, the categorized TyG index and Cox proportional hazards regression models were utilized.

RESULTS

A total of 652 patients were enrolled in the final analysis (male: 83.7%, age: 58.2 ± 10.49 years). The average TyG index was 8.8 ± 0.57. CTO PCIs were procedurally successfully completed in 503 (77.15%) patients. During the follow-up period of 22.8 ± 3.84 months, 73 (11.19%) major adverse cardiovascular and cerebral events (MACCEs) occurred. When fully adjusted, there was a 2.09-fold risk for MACCEs among patients with the highest TyG index compared with those with the lowest TyG index [T2 vs. T1: hazard ratio (HR) 1.24, 95% confidence interval (CI) 0.65-2.38, P = 0.057; T3 vs. T1: HR 2.09, 95% CI 1.14-3.86, P = 0.018; P for trend = 0.036]. The restricted cubic spline (RCS) analysis showed that the HR for MACCEs increased as the TyG index increased over 8.71 [HR per standard deviation (SD) 1.740, 95% CI 1.23-2.46, P = 0.002]. The risk of MACCEs increased with increasing tertiles of TyG index in successful CTO PCI patients and nondiabetes mellitus (DM) patients (P < 0.05) but not in patients with failed CTO PCI and DM patients.

CONCLUSION

The study revealed that the TyG index had significant relevance to cardiovascular risk in CTO patients and suggests that the TyG index is feasible for predicting cardiovascular risk in CTO patients.

With a Little Help From My Friends: the Role of the Renal Collateral Circulation in Atherosclerotic Renovascular Disease

The collateral circulation can adapt to bypass major arteries with limited flow and serves a crucial protective role in coronary, cerebral, and peripheral arterial disease. Emerging evidence indicates that the renal collateral circulation can similarly adapt and thereby limit kidney ischemia in atherosclerotic renovascular disease. These adaptations predominantly include recruitment of preexisting microvessels for arteriogenesis, with de novo vessel formation playing a limited role. Yet, adaptations of the renal collateral circulation in renovascular disease are often insufficient to fully compensate for the limited flow within an obstructed renal artery and may be hampered by the severity of obstruction or patient comorbidities. Experimental strategies have attempted to circumvent limitations of collateral formation and improve the prognosis of patients with various ischemic vascular territories. These have included pharmacological approaches such as endothelial growth factors, renin-angiotensin-aldosterone system blockade, and If-channel-blockers, as well as interventions like preconditioning, exercise, enhanced external counter-pulsation, and low-energy shock-wave therapy. However, few of these strategies have been implemented in atherosclerotic renovascular disease. This review summarizes current understanding regarding the development of renal collateral circulation in atherosclerotic renovascular disease. Studies are needed to apply lessons learned in other vascular beds in the setting of atherosclerotic renovascular disease to develop new treatment regimens for this patient group.

Manual Thrombus Aspiration and its Procedural Stroke Risk in Myocardial Infarction

Background

The previous large‐scale randomized controlled trial showed that routine thrombus aspiration (TA) during percutaneous coronary intervention (PCI) was associated with an increased risk of stroke. However, real‐world clinical evidence is still limited.

Methods and Results

We investigated the association between manual TA and stroke risk during primary PCI in the OACIS (Osaka Acute Coronary Insufficiency Study) database (N=12 093). The OACIS is a prospective, multicenter registry of myocardial infarction. The primary end point of the present study is stroke at 7 days. A total of 9147 patients who underwent primary PCI within 24 hours of hospitalization were finally analyzed (TA group, n=4448, versus non‐TA group, n=4699 patients). TA was independently associated with risk of stroke at 7 days (odds ratio [OR], 1.92 [95% CI, 1.19‒3.12]; P=0.008) in the simple logistic regression model, while the multilevel random effects logistic regression model with hospital treated as a random effect showed that manual TA was not associated with incremental risk of stroke at 7 days (OR, 0.91 [95% CI, 0.71‒1.16]; P=0.435). The 7‐day stroke risk of manual TA was significantly heterogeneous in different institutions (P_{for interaction}=0.007).

Conclusions

Manual TA during primary PCI for patients with acute myocardial infarction was independently associated with the overall increased risk of periprocedural stroke. However, this result was substantially skewed because of institution specific risk variation, suggesting that the periprocedural stroke may be preventable by prudent PCI procedure or appropriate periprocedural management.

Registration

URL: https://upload.umin.ac.jp/cgi‐open‐bin/ctr_e/ctr_view.cgi?recptno=R000005464. Unique identifier: UMIN000004575.

Do collaterals visualized on coronary angiography impact left ventricle ejection fraction among Asian Indians presenting with acute coronary syndrome?-The Deucalion Study

BACKGROUND

The coronary collaterals have been ascribed as a potential alternative source of myocardial perfusion to the extent that some suggest it as a "natural bypass"! We proposed to evaluate the impact of the extent of collaterals on left ventricle ejection fraction among Asian Indians presenting with acute coronary syndrome.

METHODS

This was a retrospective, all-comers study performed on consecutive 3614 patients presenting with the acute coronary syndrome. Angiograms were evaluated for collaterals graded according to Rentrop's classification among group A (grades 0 and 1) and group B (grades 2 and 3) collaterals.

RESULTS

Patients were matched for traditional cardiovascular risk factors in groups A and B as well as for ST elevation myocardial infarction and non-ST elevation myocardial infarction subgroups in both the groups. Grades 2 and 3 collaterals were significantly (P = 0.04) higher in patients with non-ST elevation myocardial infarction-266/1319 (20.17%), as compared to ST elevation myocardial infarction-group 400/2295 (17.43%). Left ventricle ejection fraction on presentation was better preserved in group A as compared to group B in those with double-vessel disease and triple-vessel disease patients with non-ST elevation myocardial infarction, whereas it was better in single-vessel disease and triple-vessel disease patients with ST elevation myocardial infarction. The inverse correlation (r = -0.111, P = 0.000) existed between left ventricle ejection fraction and grades of collaterals.

CONCLUSION

Patients with the single-vessel disease were more likely to have poor coronary collateral as compared to double-vessel disease/triple-vessel disease. Despite higher grade coronary collateral among Asian Indians presenting with acute coronary syndrome, both non-ST elevation myocardial infarction and ST elevation myocardial infarction patients with triple-vessel disease had significantly lower left ventricle ejection fraction. This paradoxically brings out worse left ventricle ejection fraction on presentation in those with double-vessel disease and triple-vessel disease with ST elevation myocardial infarction and single-vessel disease and triple-vessel disease with ST elevation myocardial infarction despite higher grade of coronary collateral representing as "Asian Indian Paradox" in our cohort.

Association between the triglyceride glucose index and coronary collateralization in coronary artery disease patients with chronic total occlusion lesions

Background

Recent studies have substantiated the role of the triglyceride glucose (TyG) index in predicting the prognosis of coronary artery disease (CAD) patients, while no relevant studies have revealed the association between the TyG index and coronary collateralization in the event of coronary chronic total occlusion (CTO). The current study intends to explore whether, or to what extent, the TyG index is associated with impaired collateralization in CAD patients with CTO lesions.

Methods

The study enrolled 1093 CAD patients undergoing cardiac catheterization for at least one CTO lesion. Data were collected from the Beijing Anzhen Hospital record system. The degree of collaterals was determined according to the Rentrop classification system. The correlation between the TyG index and coronary collateralization was assessed.

Results

Overall, 318 patients were included in a less developed collateralization (Rentrop classification 0-1) group. The TyG index was significantly higher in patients with impaired collateralization (9.3±0.65 vs. 8.8±0.53, P<0.001). After adjusting for various confounding factors, the TyG index remained correlated with the occurrence of impaired collateralization, with odds ratios (ORs) of 1.59 and 5.72 in the T2 and T3 group compared with the first tertile group (P<0.001). In addition, subgroup analysis showed that higher TyG index values remained strongly associated with increased risk of less developed collateralization. To compare the risk assessment efficacy for the formation of collateralization between the TyG index and other metabolic abnormality indicators, an area under the receiver-operating characteristic (ROC) curve (AUC) was obtained. A significant improvement in the risk assessment performance for impaired collateralization emerged when adding the TyG index into a baseline model.

Conclusions

The increased TyG index is strongly associated with less developed collateralization in CAD patients with CTO lesions and its risk assessment performance is better than single metabolic abnormality indicators.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12944-021-01574-x.

In-hospital mortality among consecutive patients with ST-Elevation myocardial infarction in modern primary percutaneous intervention era ~ Insights from 15-year data of single-center hospital-based registry ~

Objective

To clarify the association of detailed angiographic findings with in-hospital outcome after primary percutaneous coronary intervention (p-PCI) for ST-elevation myocardial infarction (STEMI) in Japan.

Background

Data regarding the association of detailed angiographic findings with in-hospital outcome after STEMI are limited in the p-PCI era.

Methods

Between January-2004 and December-2018, 1735 patients with STEMI (mean age, 68.5 years; female, 24.6%) who presented to the hospital in the 24-hours after symptom onset and underwent p-PCI were evaluated using the disease registries. The registry is an ongoing, retrospective, single-center hospital-based registry.

Results

The 30-day mortality rate and in-hospital mortality rate were 7.7% and 9.2%, respectively. Independent predictors of in-hospital mortality were ejection fraction (EF) < 40% [adjusted Odds Ratio (aOR), 4.446, p < 0.001], culprit lesions in the left coronary artery (LCA) (aOR, 2.940, p < 0.001) compared with those in the right coronary artery, Killip class > II (aOR, 7.438; p < 0.001), chronic kidney disease (CKD) (aOR, 4.056; p < 0.001), final thrombolysis in myocardial infarction (TIMI) grades 0/1/2 (aOR, 1.809; p = 0.03), absence of robust collaterals (aOR, 17.309; p = 0.01) and hypertension (aOR, 0.449; p = 0.01).

Conclusions

Among the consecutive patients with STEMI, the in-hospital mortality rate after p-PCI significantly improved in the second half. Not only CKD, Killip class > II, and EF < 40%, but also the angiographic findings such as culprit lesions in the LCA, absence of very robust collaterals, and final TIMI grades <3 were associated with an increased risk of in-hospital mortality.

Prevalence of the Japanese high bleeding risk criteria and its prognostic significance for fatal bleeding in patients with acute myocardial infarction

BACKGROUND

The Japanese high-bleeding-risk criteria (Japanese-HBR), modified criteria of the Academic Research Consortium (ARC) HBR, has been recently proposed. We aimed to investigate the prevalence of the ARC-HBR and the Japanese-HBR, and to assess their prognostic significance in patients with acute myocardial infarction (AMI).

METHODS AND RESULTS

We applied the ARC-HBR and the Japanese-HBR criteria to the OACIS prospective multicenter acute myocardial infarction registry (12,093 patients, 66 ± 12 years, 9,096 males). The primary endpoint was fatal bleeding (BARC-5). Median follow-up duration was 4.84 [inter-quartile range 1.35, 5.01] years. Prevalence of the ARC-HBR was 43.8%, while that of the Japanese-HBR was 61.8%. Cumulative incidence of fatal bleeding was higher in the ARC-HBR group than in the no ARC-HBR group at 1 year (1.3 vs. 0.6%) and at 5 years (2.0 vs. 0.7%). The Kaplan-Meier curves stratified by the Japanese-HBR criteria more prominently diverged (1.3 vs. 0.2% at 1 year; and 1.9 vs. 0.3% at 5 years). The Japanese-HBR criteria showed superior discriminative performance over the ARC-HBR criteria (C-statistics: 0.677 vs. 0.598, P < 0.001).

CONCLUSIONS

In the real-world Japanese AMI registry, nearly half of the patients fulfilled the criteria of ARC-HBR, and two-thirds met the Japanese-HBR. Our findings support the validity of both ARC- and Japanese-HBR criteria in AMI patients but encourage the future application of the Japanese-HBR criteria to the Japanese AMI cohort.

TRIAL REGISTRATION NUMBER

UMIN000004575.

Impact of age on reperfusion success and long-term prognosis in ST-segment elevation myocardial infarction - A cardiac magnetic resonance imaging study

Background

Coronary collateral circulation and conditioning from remote ischemic coronary territories may protect culprit myocardium in the elderly, and younger STEMI patients could suffer from larger infarcts. We evaluated the impact of age on myocardial salvage and long-term prognosis in a contemporary STEMI cohort.

Methods

Of 1603 included STEMI patients 807 underwent cardiac magnetic resonance. To assess the impact of age on infarct size and left ventricular ejection fraction (LVEF) as well as the composite endpoint of death and re-hospitalization for heart failure we stratified the patients by an age cut-off of 60 years.

Results

Younger STEMI patients had smaller final infarcts (10% vs. 12%, P = 0.012) and higher final LVEF (60% vs. 58%, P = 0.042). After adjusting for multiple potential confounders age did not remain significantly associated with infarct size and LVEF. During 4-year follow-up, the composite endpoint occurred less often in the young (3.2% vs. 17.2%; P < 0.001) with a univariate hazard ratio of 5.77 (95% CI, 3.75–8.89; p < 0.001). Event estimates of 4 subgroups (young vs. elderly and infarct size beyond vs. below median) showed a gradual increase in the occurrence of the composite endpoint depending on both age and acute infarct size (log-rank p < 0.001).

Conclusion

Having a STEMI after entering the seventh decade of life more than quadrupled the risk of future death or re-hospitalization for heart failure. Risk of death and re-hospitalization depended on both advanced age and infarct size, albeit no substantial difference was found in infarct size, LVEF and salvage potential between younger and elderly patients with STEMI.

Does the extent of collaterals influence the severity of the myocardial injury as assessed by elevation in biomarkers?

Introduction: Quantitative analysis of cardiac biomarkers, troponin I and CPK-MB, estimates the extent of myocardial injury while extent of benefit from coronary collateral circulation (CCC) to protect myocardium during acute myocardial infarction (AMI) needs validation. We analysed if the extent of collaterals had impact on baseline biomarkers at the time of coronary angiogram.

Methods: We analysed 3616 consecutive patients who presented with AMI and underwent invasive coronary angiography (CAG) with intent to revascularisation with biomarkers assessment at the time of CAG. CCC to Infarct related artery (IRA) were graded as per Rentrop grading viz. poorly-developed CCC (Grade 0/1 as Group A) and well-developed CCC (Grade 2/3 as Group B).

Results: Both groups (A and B) were matched for demographics, traditional risk factors, SYNTAX 1 Score, time to CAG from onset of angina and eGFR. 36.59% of patients had Non-ST segment elevation myocardial infarction (NSTEMI) as compared to 63.41% ST -segment elevation infarction (STEMI). Overall Troponin I (P =0.01, P =0.01) and CPK MB (P =0.00, P =0.002) values were lower in group B in both NSTEMI and STEMI groups respectively. Troponin I and CPK-MB were significantly lower in group B [with NSTEMI for SVD (Single vessel disease) (P =0.05) and DVD (Double vessel disease) (P =0.04),but not for TVD (Triple vessel disease) and with STEMI in SVD (P =0.01), DVD (P =0.01) and TVD (P =0.001)].

Conclusion: Patients with well-developed coronary collaterals had a lower rise in biomarkers in AMI as compared to those with poor collaterals amongst both NSTEMI and STEMI groups.

A preoperative modified Allen test result may be associated with long term mortality after hemodialysis access construction

BACKGROUND

The modified Allen test (MAT) is a simple bedside method determining collateral hand circulation prior to hemodialysis (HD) access surgery. Hand ischemia as reflected by low systolic finger pressures (P_dig) is associated with high mortality rates in severe kidney disease (CKD) patients. Aim of the present study was to assess a possible relation between absolute finger pressure drop (∂P_dig) during a preoperative MAT and mortality after a first HD access construction.

METHODS

P_dig (systolic pressure, mmHg) was measured using digital plethysmography following compression of radial and ulnar arteries in CKD patients just before access surgery between January 2009 and December 2018 in one center. The greatest ∂P_dig of both index fingers was used for analysis. Cardiovascular and overall mortality were assessed during the following 4 years using the ERA-EDTA classification system (codes 11, 14-16, 18, 22-26, 29). Cox regression analysis determined possible associations between ∂P_dig and mortality.

RESULTS

Complete data sets were available in 108 patients (male n = 71; age 70 years ±12; mean follow up (FU) 1.6 years ±0.1; FU index 99% ±1). Median ∂P_dig was 31 mmHg (range 0-167 mmHg). Patients having cardiovascular disease (CV+) demonstrated higher ∂P_dig values (CV+ 44 ± 5 mmHg vs CV- 29 ± 3 mmHg, p = 0.012). A total of 26 patients (24%) died during FU (CV+ death, n = 16; 62%). For each 10 mmHg ∂P_dig increase, overall mortality increased by 10%, and CV+ mortality by 15% (overall mortality: HR 1.10 [1.01-1.22], p = 0.048; CV+ mortality: 1.15 [1.03-1.29], p = 0.017). Following correction for age, ∂P_dig remained associated with CV+ mortality (HR 1.13 [1.00-1.26], p = 0.043).

CONCLUSIONS

A large drop in systolic finger pressure during a preoperative MAT is related to mortality after primary HD access surgery. The role of this potential novel risk parameter requires confirmation in a larger population.

Incomplete protective effect of coronary collateral circulation for acute myocardial infarction patients

The short-term and long-term effects of coronary collateral circulation (CCC) discovered after acute myocardial infarction (AMI) are still debatable. This retrospective cohort study aimed to explore the clinical significance of CCC for AMI patients.A consecutive series of 323 AMI patients with CCC and 1339 AMI subjects without CCC were enrolled, most of them received percutaneous coronary intervention after AMI. Comparisons between CCC subjects and non-CCC population and between CCC sub-groups were applied regarded to basic clinical characteristics, stenosis extent indicated by Gensini score, myocardial infarction size estimated by peak concentration of troponin I (TnI), and left ventricular function evaluated by peak value of N-terminal pro-brain natriuretic peptide (NT-proBNP). Multiple linear regressions for NT-proBNP and TnI, and Kaplan-Meier curves for 5-years' main cardiovascular event (MACE) were also analyzed.CCC might provide incomplete protection by preventing excessive myocardial infarction but not a poorer heart function during AMI and CCC had no obvious protective effect on 5-years' MACE for AMI patients. More attentions should be paid to heart function for CCC patients during AMI.

Prognostic implications of the rapid recruitment of coronary collaterals during ST elevation myocardial infarction (STEMI): a meta-analysis of over 14,000 patients

Acute coronary collateralisation of an infarct-related arterial (IRA) territory may be identified during angiography for ST elevation myocardial infarction (STEMI). Whether the presence or absence of these collaterals affects outcomes remains uncertain. A search of EMBASE, MEDLINE and Cochrane Library, using the Preferred Reporting Items for Systematic reviews and Meta-Analysis (PRISMA) guidelines was conducted to identify studies which reported on the association between coronary collaterals and in-hospital and longer term mortality, left ventricular ejection fraction (LVEF), risk of repeat acute myocardial infarction (AMI) and repeat revascularisation. Patients with Rentrop grade 0 or 1 were defined as poor collaterals whilst those with Rentrop grade two or three were defined as those with robust collaterals. Studies were eligible if they included patients ≥ 18 years of age who had immediate coronary angiography for STEMI. Included studies were observational which recorded the degree of collateral blood flow to the IRA. Two investigators reviewed all citations using a predefined protocol with final consensus for all studies, the data from which was then independently entered to ensure fidelity of results. Inverse variance random effects model for the meta-analysis along with risk of bias assessment was performed. 20 studies with a total of 14,608 patients were identified and included in the analysis. Patients with robust collaterals had lower mortality (OR 0.55, 95% CI 0.48-0.64), both in-hospital (OR 0.47, 95% CI 0.35-0.63) and longer term (OR 0.58, 95% CI 0.46-0.75). Patients with robust collaterals also had a higher mean LVEF (SMD 0.23, 95% CI 0.10-0.37). There was no difference in the rates of AMI or repeat revascularisation between patients with robust or poor collaterals. The presence of robust collaterals during STEMI is associated with reduced in-hospital and longer term mortality and improved left ventricular function. These findings have implications for prognostication and identifying patients who require close monitoring following STEMI.

In Acute ST-Segment Elevation Myocardial Infarction, Coronary Wedge Pressure Is Associated with Infarct Size and Reperfusion Injury as Evaluated by Cardiac Magnetic Resonance Imaging

Background. Coronary collateral flow influences patient prognosis in the setting of acute myocardial infarction. However, few data exist about the relation between coronary collaterals, infarct size, and reperfusion injury. The angiographic Rentrop score is prone to subjectivism and to the inherent limitations of angiographic images. Its prognostic value is controversial in the setting of acute myocardial infarction. The invasive measurement of coronary wedge pressure (CWP) represents an alternative to Rentrop score for the evaluation of coronary collateralization. Our study evaluates pre-revascularization CWP as a predictor of infarct size and reperfusion injury as evaluated by cardiac magnetic resonance imaging. Methods. Patients with acute ST-elevation myocardial infarction underwent preprocedural CWP measurement and primary percutaneous coronary intervention. Infarct size, microvascular obstruction, intramyocardial edema, and intramyocardial hemorrhage were evaluated by cardiac magnetic resonance imaging. Results. Mean CWP was inversely associated with infarct size p=0.01, microvascular obstruction p=0.02, intramyocardial edema p=0.05, and intramyocardial hemorrhage p=0.01. An excellent association was found between mean CWP and an infarct size ≥24% of left ventricular mass (AUC = 0.880, p=0.007), with an optimal cutoff value ≤24.5 mmHg. Both intramyocardial edema p=0.02 and hemorrhage p=0.03 had a larger extent in patients with coronary wedge pressure ≤24.5 mmHg. Rentrop grade <2 was associated with larger infarct size p=0.03, but not with the extent of edema, microvascular obstruction, or intramyocardial hemorrhage. Conclusions. Pre-revascularization CWP was a predictor of infarct size and was significantly associated with a larger extent of intramyocardial edema and intramyocardial hemorrhage. Rentrop grade <2 was associated with a larger infarct size, but had no influence on reperfusion injury. The clinical trial is registered with NCT03371784.

Effect of Recruitment of Acute Coronary Collaterals on In-Hospital Mortality and on Left Ventricular Function in Patients Presenting With ST Elevation Myocardial Infarction

Recruitment of the coronary collateral circulation is frequently observed during ST elevation myocardial infarction (STEMI) and is of uncertain significance. The aim of this study was to identify and determine the predictors and prognostic implications of the presence of robust collaterals during STEMI. All patients presenting to a large tertiary centre with a STEMI undergoing percutaneous coronary intervention from 2010 to 2018 were reviewed. Patients with poor collateral recruitment were defined as those with Rentrop grade 0 or 1 collaterals, whilst patients with robust collateral recruitment were defined as Rentrop grade 2 or 3. A total of 1,625 patients were included in the study, with 1,280 (78.8%) patients having poor collateral recruitment and 345 patients (21.2%) having robust collateral recruitment. Patients with robust collaterals were younger (63.1 vs 65.1 years, p < 0.05), had a longer ischemic time (628.5 minutes vs 433.1 minutes, p < 0.0001), and more likely to have a chronic total occlusion of a noninfarct related artery (10.4% vs 5.3%, p < 0.001). The presence of robust collaterals was associated with higher rates of normal or mildly impaired left ventricular function (83.5% vs 63.2%, p < 0.0001) and lower in-hospital mortality (2.1% vs 7.6%, p < 0.0001). After correcting for left ventricular function, collateral recruitment was not an independent predictor of mortality. In conclusion, in patients presenting with STEMI, the presence of robust coronary collaterals appears to be associated with improved left ventricular function. Further research is required to identify mechanisms of collateral maturation and recruitment.

Comparison between radial versus femoral percutaneous coronary intervention access in Indonesian hospitals, 2017-2018: A prospective observational study of a national registry

BACKGROUND

Coronary heart disease is a leading cause of death in Indonesia and percutaneous coronary intervention (PCI) is a routinely performed procedure. The aim of this study is to provide real-world insight on the demographics of coronary artery disease and comparison between radial compared to femoral PCI in Indonesia, which performed radial access whenever possible.

METHODS

This is a prospective cohort study involving 5420 patients with coronary artery disease who underwent PCI at 9 participating centers in the period of January 2017-December 2018.

RESULTS

Radial access rate was performed in 4038 (74.5%) patients. Patients receiving femoral access has a higher rate of comorbidities and complex lesions compared to radial access. The incidence of in-hospital mortality, cardiogenic shock, major arrhythmia, and tamponade were higher in femoral group. The incidence of in-hospital mortality was 114 (2.1%). New-onset angina (OR 3.412), chronic renal failure (OR 3.47), RBBB (OR 4.26), LBBB (OR 6.26), left main stenosis PCI (OR 3.58), cardiogenic shock (OR 4.9), and arrhythmia (OR 15.59) were found to be independent predictors of in-hospital mortality. Radial access did not independently affect in-hospital mortality. In propensity-matched cohort, radial access was not associated with lower in-hospital mortality in both bivariable and multivariable model. However, radial access was associated with reduced in-hospital mortality in STEMI subgroup (OR 0.31).

CONCLUSION

Higher rate of adverse events was noted on the femoral access group. However, it might stem from the fact that patients with more comorbidities and complex lesions are more likely to be assigned to femoral access-group. Neither radial or femoral access is superior in terms of in-hospital mortality upon propensity-score matching/multivariable analysis.

Spontaneous coronary collateral recruitment in patients with recurrent ST elevation myocardial infarction (STEMI)

The spontaneous recruitment of acute coronary collaterals in the setting of an ST elevation myocardial infarction (STEMI) is seen frequently in those patients undergoing primary percutaneous coronary intervention (pPCI) and is associated with improved clinical outcomes. However, it is unknown whether in patients who present with a recurrent STEMI, the degree of collateral recruitment remains the same as in the index procedure. We reviewed all patients presenting to our tertiary centre with a STEMI undergoing primary or rescue percutaneous coronary intervention (PCI) from July 2010 until December 2018. We identified patients who presented with a recurrent STEMI following their index procedure. We defined patients with poor collateral recruitment as Rentrop grade 0 or 1, whilst patients with robust collateral recruitment as Rentrop grade 2 or 3. Of the 1795 patients who were identified, there were 27 cases in 25 patients who presented with a repeat STEMI following their index procedure. The median time between cases was 12.8 days (IQR 2.3-589.5 days). Compared to the index case, there was no statistically significant difference in the degree of collateral recruitment in recurrent presentations (Z = - 0.378, p = 0.70). In those patients presenting more than 6 months following the index procedure, the median time between cases was 654.5 days (IQR 479.5-1151.9). There was no difference in the degree of collateral recruitment in recurrent presentations (Z = 0.000, p = 1.0). Cases which had poorer collateral recruitment in recurrent presentations were less likely to be current smokers (0% vs 50%, p < 0.001) and less likely to have diabetes (0% vs 27.3%, p < 0.05) The recruitment of spontaneous coronary collaterals remains constant in recurrent STEMI presentations suggesting an innate biological process rather than merely a manifestation of alteration of haemodynamic blood flow. Further investigations to identify these processes is required.

Angiographically visible coronary artery collateral circulation improves prognosis in patients presenting with acute ST segment-elevation myocardial infarction

BACKGROUND

Coronary collaterals are often seen supplying retrograde flow to an acutely occluded arterial territory. Whether this early collateralization offers prognostic benefit is not well established.

METHODS

We analyzed data from all patients presenting to our regional cardiac unit with acute ST-elevation myocardial infarction requiring immediate angiography (years 1999-2017). Data on all patients is entered prospectively into a bespoke tailored database prior to knowledge of patient outcome. Only patients with TIMI 0 or 1 flow in the infarct-related vessel were included in the analysis. In-hospital and long-term outcome were assessed according to the presence or absence of angiographically visible collateral flow prior to treatment of the occluded vessel.

RESULTS

Two thousand five hundred and forty-two patients were included in the analysis. 76% of these (n = 1944) had TIMI 0/1 flow at angiography. Angiographically-visible collateralization was seen in 17% (n = 322) and was more commonly observed in the right coronary artery (64%) than in the left anterior descending (25%) or Cx (6%). Cardiogenic shock (10.8%) and use of an intra-aortic balloon pump (5.4%) were more frequent in patients without coronary collateralisation (p = .04 and p = .02, respectively). The presence of collaterals improved long term survival (95% CI 11.4-18.7 months; p < .01).

CONCLUSION

One-sixth of patients with STEMI have angiographically visible collaterals to the infarcted territory. Patients without collaterals are more likely to present in cardiogenic shock. The presence of angiographically visible collaterals at the time of STEMI is associated with an improved long-term survival.

Stimulation of Collateral Vessel Growth by Inhibition of Galectin 2 in Mice Using a Single-Domain Llama-Derived Antibody

Background

In the presence of arterial stenosis, collateral artery growth (arteriogenesis) can alleviate ischemia and preserve tissue function. In patients with poorly developed collateral arteries, Gal‐2 (galectin 2) expression is increased. In vivo administration of Gal‐2 inhibits arteriogenesis. Blocking of Gal‐2 potentially stimulates arteriogenesis. This study aims to investigate the effect of Gal‐2 inhibition on arteriogenesis and macrophage polarization using specific single‐domain antibodies.

Methods and Results

Llamas were immunized with Gal‐2 to develop anti–Gal‐2 antibodies. Binding of Gal‐2 to monocytes and binding inhibition of antibodies were quantified. To test arteriogenesis in vivo, Western diet‐fed LDLR.(low‐density lipoprotein receptor)–null Leiden mice underwent femoral artery ligation and received treatment with llama antibodies 2H8 or 2C10 or with vehicle. Perfusion restoration was measured with laser Doppler imaging. In the hind limb, arterioles and macrophage subtypes were characterized by histology, together with aortic atherosclerosis. Llama‐derived antibodies 2H8 and 2C10 strongly inhibited the binding of Gal‐2 to monocytes (93% and 99%, respectively). Treatment with these antibodies significantly increased perfusion restoration at 14 days (relative to sham, vehicle: 41.3±2.7%; 2H8: 53.1±3.4%, P=0.016; 2C10: 52.0±3.8%, P=0.049). In mice treated with 2H8 or 2C10, the mean arteriolar diameter was larger compared with control (vehicle: 17.25±4.97 μm; 2H8: 17.71±5.01 μm; 2C10: 17.84±4.98 μm; P<0.001). Perivascular macrophages showed a higher fraction of the M2 phenotype in both antibody‐treated animals (vehicle: 0.49±0.24; 2H8: 0.73±0.15, P=0.007; 2C10: 0.75±0.18, P=0.006). In vitro antibody treatment decreased the expression of M1‐associated cytokines compared with control (P<0.05 for each). Atherosclerotic lesion size was comparable between groups (overall P=0.59).

Conclusions

Inhibition of Gal‐2 induces a proarteriogenic M2 phenotype in macrophages, improves collateral artery growth, and increases perfusion restoration in a murine hind limb model.

A noninvasive and highly sensitive approach for the assessment of coronary collateral circulation by 192-slice third-generation dual-source computed tomography

The coronary collateral circulation (CCC) is an alternative source of blood supply when the original vessels fail to provide sufficient blood. The accurate detection of CCC is critical for the treatment of ischemic heart disease, especially when the stent surgery is not an option. The assessment of minute vessels such as coronary collateral arteries is challenging. The objective of this study was to assess the feasibility of detection and classification of CCC using the192-slice third-generation dual-source computed tomography angiography (192-slice DSCT CTA).Eight hundred patients (450 men and 350 women, mean age: 56 ± 11 years) with complete or subtotal occlusion of at least 1 major coronary artery were enrolled for our study. February 2016 and September 2018, the patient both 192-slice DSCT CTA and conventional coronary angiography (CAG) were performed in all enrolled patients. The interval between two approaches for a given patient was 6.1 ± 3.7 days (Range: 1-15). The diagnostic accuracy of 192-slice DSCT CTA was evaluated by comparing it with that of CAG. The identified CCC was graded according to the Rentrop classification.The prevalence among patients of having at least 1 CCC was 43.8%. The sensitivity for detecting CCC by 192-slice DSCT was 91.7% (95% CI: 88.3% to 94.3%), specificity was 95.5% (95% CI: 93.1% to 97.2%), positive predictive value was 94.3% (95% CI: 91.5% to 96.2%), and negative predictive value was 93.3% (95% CI: 90.9% to 95.3%). Cohen-Kappa analysis showed that the consistency of the correct classification of CCC using CAG and 192-slice DSCT was very high with the kappa coefficient (κ) of 0.94 (95% CI: 0.91-0.96, P value = .01). Additionally, the radiation dose for 192-slice DSCT was as low as 0.42 ± 0.04 mSv (range, 0.35-0.43 mSv).The 192-slice DSCT CTA is a reliable and sensitive non-invasive method for the evaluation of CCC with low radiation doses.

Effect of Coronary Collaterals on Prognosis in Patients Undergoing Primary Percutaneous Coronary Intervention for Acute ST-Segment Elevation Myocardial Infarction: A Meta-Analysis

The impact of coronary collaterals on the prognosis in patients with acute ST-segment elevation myocardial infarction (STEMI) in the era of coronary revascularization remains controversial. The purpose of this meta-analysis was to investigate the effect of coronary collateral on clinical outcomes, especially mortality (≥6 months), in patients undergoing primary percutaneous coronary intervention (PCI) for STEMI. Eligible observational studies were selected by searching PubMed, EMBASE, and Cochrane Library up to August 9, 2017. Overall, 14 observational studies involving 10 411 patients were included. Coronary collaterals were found to reduce the risk of long-term mortality (≥6 months; risk ratio [RR]: 0.65, 95% confidence interval [CI]: 0.55-0.76) as well as in-hospital plus 30-day mortality (RR: 0.61, 95% CI: 0.47-0.78) in patients undergoing PCI for STEMI. In addition, pooling the risk-adjusted or propensity-matched data showed a significant reduction in long-term mortality (RR: 0.68, 95% CI: 0.49-0.95) and in-hospital plus 30-day mortality (RR: 0.27, 95% CI: 0.13-0.55) in patients with collateral circulation. However, no significant difference was found in the risk of recurrent myocardial infarction and target vessel revascularization between the 2 groups. Therefore, it was found that coronary collaterals have a beneficial effect on long-term survival (≥6 months) as well as in-hospital plus 30-day survival in patients undergoing primary PCI for STEMI.

Impact of Admission Blood Glucose on Coronary Collateral Flow in Patients with ST-Elevation Myocardial Infarction

In patients with acute myocardial infarction, glucose metabolism is altered and acute hyperglycemia on admission is common regardless of diabetes status. The development of coronary collateral is heterogeneous among individuals with coronary artery disease. In this study, we aimed to investigate whether glucose value on admission is associated with collateral flow in ST-elevation myocardial infarction (STEMI) patients. We retrospectively evaluated 190 consecutive patients with a diagnosis of first STEMI within 12 hours of onset of chest pain. Coronary collateral development was graded according to Rentrop classification. Rentrop 0-1 was graded as poor collateral development, and Rentrop 2-3 was graded as good collateral development. Admission glucose was measured and compared between two groups. Mean admission glucose level was 173.0 ± 80.1 mg/dl in study population. Forty-five (23.7%) patients had good collateral development, and 145 (76.3%) patients had poor collateral development. There were no statistically significant differences in demographic characteristics between two groups. Three-vessel disease was more common in patients with good collateral development (p=0.026). Mean admission glucose level was higher in patients with poor collateral than good collateral (180.6 ± 84.9 mg/dl versus 148.7 ± 56.6 mg/dl, resp., p=0.008). In univariate analysis, higher admission glucose was associated with poor collateral development, but multivariate logistic regression analysis revealed a borderline result (odds ratio 0.994, 95% CI 0.989-1.000, p=0.049). Our results suggest that elevated glucose on admission may have a role in the attenuation of coronary collateral blood flow in acute myocardial infarction. Further studies are needed to validate our results.

Reciprocal ST-Segment Changes in Myocardial Infarction: Ischemia at Distance Versus Mirror Reflection of ST-Elevation

BACKGROUND

Reciprocal ST-depression in the electrocardiograms (ECGs) of patients with ST-elevation myocardial infarction (STEMI) results from either true ischemia at a distance via collateral circulation diverting blood to the infarcted region or an electrical phenomenon that results from a mirror reflection of ST-elevation. We aimed to identify the role of reciprocal ECG changes in predicting collateral circulation to the infarcted area determined angiographically.

METHODS

In a retrospective study, ECG and angiography of 53 STEMI patients admitted to SUNY Upstate Medical University in 2014 were reviewed independently by experts blinded to the results of ECG and coronary angiography.

RESULTS

Reciprocal changes (RC) in ECG were present in 41 patients (77%) and on angiography, 14 patients (26%) exhibited collateral vessels to the ischemic areas. No correlation was found between the presence of RC and collateral circulation (P = 0.384), or between the depth of reciprocal ST-depression and the degree of the collateral circulation (P = 0.195). However, 84% of patients without collaterals exhibited resolution of RC after successful percutaneous coronary intervention (PCI) (P = 0.036), suggesting that the ST depressions that resolved after reperfusion were directly caused by the culprit vessel. Patients without RC presented late after symptom onset (9.25 versus 3.83 hours, P = 0.004), also suggesting time related resolution.

CONCLUSIONS

RC had no relation to or predictive value for collaterals on angiography. Among late presenting patients, RC were less frequent. Thus, reciprocal ST-depression may represent subendocardial ischemia from the primary coronary event or simply an electrical phenomenon, rather than ischemia at distance from impaired collateral circulation.