Relationship between collateral circulation and successful myocardial reperfusion in acute myocardial infarction: a subanalysis of the PREMIAR trial

A nomogram for predicting the risk of no-reflow after primary percutaneous coronary intervention in elderly patients with ST-segment elevation myocardial infarction

Background

The purpose of this study was to screen the predictive factors of no-reflow after a percutaneous coronary intervention (PCI) in elderly patients with ST-segment elevation myocardial infarction (STEMI), and to construct a nomogram model, to guide clinical treatment.

Methods

A total of 551 elderly STEMI patients (age >65) underwent direct PCI were randomly classified into training group (n=386, 70%) and validation group (n=165, 30%). All patients in the two groups were divided into a no-reflow group and a normal blood flow group according to whether there was a no-reflow phenomenon. Univariable and multivariable logistic regression analysis was used to analyze the relevant data, including demographic characteristics, clinical characteristics, coronary angiography results, electrocardiogram (ECG) results, and biochemical indicators. Then, a nomogram model was constructed on the screened risk factors. The performance of the nomogram was evaluated in terms of discrimination and calibration. The nomogram was further confirmed in the internal validation group. Additionally, decision curve analysis (DCA) was applied to assess the clinical usefulness of the nomogram.

Results

Five remarkable risk factors were determined: preoperative TIMI blood flow, the diameter of the target lesion, collateral circulation, pulse pressure, and the number of leads for ST-segment elevation. The nomogram involving these five risk factors showed full calibration and discrimination in the training group, with an AUC of 0.71 (95% CI: 0.66–0.77). It was confirmed in the validation group, and the entire cohort and the AUC were 0.64 (95% CI: 0.56–0.73) and 0.69 (95% CI: 0.65–0.74), respectively. Whether in the training group or the verification group, the calibration curve for the probability of no-reflow phenomenon all showed considerable consistency between prediction by nomogram and actual observation. The decision curve revealed a specific role in our nomogram in clinical practice.

Conclusions

We set up a nomogram that showed absolute accuracy for the prediction of the risk of no-reflow after primary PCI in elderly STEMI patients.

Prediction of no-reflow phenomenon in patients treated with primary percutaneous coronary intervention for ST-segment elevation myocardial infarction

No-reflow is an important complication among patients with acute ST-segment elevation myocardial infarction (STEMI) undergoing percutaneous coronary intervention (PCI).A retrospective study of 1658 STEMI patients undergoing direct PCI was performed. Patients were randomly assigned at a 7:3 ratio into development cohort and validation cohort and into no-reflow and normal blood flow groups. Clinical data and laboratory examinations were compared to identify independent risk factors and establish a no-reflow risk scoring system.In the development cohort (n = 1122), 331 (29.5%) had no-reflow. Multivariate analysis showed age ≥ 65 years (OR = 1.766, 95% confidence interval (CI): 1.313-2.376, P < .001), not using angiotonase inhibitor/angiotensin receptor antagonists (OR = 1.454, 95%CI: 1.084-1.951, P = .013), collateral circulation <grade 2 (OR = 3.056, 95%CI: 1.566-5.961, P = .001), thrombosis burden ≥4 points (OR = 2.033, 95%CI: 1.370-3.018, P < .001), diameter of target lesion ≥3.5 mm (OR = 1.511, 95%CI: 1.087-2.100, P = .014), thrombosis aspiration (OR = 1.422, 95%CI: 1.042-1.941, P = .026), and blood glucose >8 mmol/L (OR = 1.386, 95%CI: 1.007-1.908, P = .045) were related to no-reflow. Receiver operating characteristic (ROC) area under the curve was 0.648 (95%CI: 0.609-0.86). At 0.349 cutoff sensitivity was 42.0%, specificity was 79.3%, positive predictive value (PPV) was 44.7%, negative predictive value (NPV) was 77.4%, P < .001. The resulting risk scoring system was tested in the validation cohort (n = 536), with 30.1% incidence of no-reflow. The area under the ROC curve was 0.637 (95%CI: 0.582-0.692). At a cutoff of 0.349 sensitivity was 53.2% and specificity was 66.7%, PPV was 41.2%, NPV was 76.4%, P < .001.The no-reflow risk scoring system was effective in identifying high-risk patients.

Influence of Cardiovascular Risk Factors, Comorbidities, Medication Use and Procedural Variables on Remote Ischemic Conditioning Efficacy in Patients with ST-Segment Elevation Myocardial Infarction

Remote ischemic conditioning (RIC) confers cardioprotection in patients with ST-segment elevation myocardial infarction (STEMI). Despite intense research, the translation of RIC into clinical practice remains a challenge. This may, at least partly, be due to confounding factors that may modify the efficacy of RIC. The present review focuses on cardiovascular risk factors, comorbidities, medication use and procedural variables which may modify the efficacy of RIC in patients with STEMI. Findings of such efficacy modifiers are based on subgroup and post-hoc analyses and thus hold risk of type I and II errors. Although findings from studies evaluating influencing factors are often ambiguous, some but not all studies suggest that smoking, non-statin use, infarct location, area-at-risk of infarction, pre-procedural Thrombolysis in Myocardial Infarction (TIMI) flow, ischemia duration and coronary collateral blood flow to the infarct-related artery may influence on the cardioprotective efficacy of RIC. Results from the on-going CONDI2/ERIC-PPCI trial will determine any clinical implications of RIC in the treatment of patients with STEMI and predefined subgroup analyses will give further insight into influencing factors on the efficacy of RIC.

Clinical risk scores predict procedural complications of primary percutaneous coronary intervention

Objective:

The predictive value of five risk score models containing clinical (PAMI-PMS, GRACE–GRS, and modified ACEF-ACEFm–scores), angiographic SYNTAX score (SXS) and combined Clinical SYNTAX score (CSS) variables were evaluated for the incidence of three procedural complications of primary percutaneous coronary intervention (pPCI): iatrogenic coronary artery dissection, angiographically visible distal embolization and angiographic no-reflow phenomenon.

Methods:

The mentioned scores and the incidence of procedural complications were retrospectively analyzed in 399 consecutive patients with acute ST-elevation myocardial infarction who underwent pPCI.

Results:

Coronary dissection, distal embolization and no-reflow occurred in 39 (9.77%), 71 (17.79%), and 108 (27.07%) subjects, respectively. Coronary dissections were significantly associated with higher GRS, ACEFm, and CSS values (all p<0.05). PMS, GRS, ACEFm, and CSS were significantly higher in patients with no-reflow (all p<0.05), while distal embolization was not predicted by any of the calculated scores. In multiple logistic regression models, GRS and ACEFm remained independent predictors of both coronary dissections (OR 3.20, 95% CI 1.56–6.54, p<0.01 and OR 2.87, 95% CI 1.27–6.45, p=0.01, respectively) and no-reflow (OR 1.71, 95% CI 1.04–2.82, p=0.03 and OR 1.86, 95% CI 1.10–3.14, p=0.01, respectively).

Conclusion:

Whereas SXS failed to predict procedural complications related to pPCI, two simple, noninvasive risk models, GRS and ACEFm, independently predicted coronary dissections and no-reflow. Pre-interventional assessment of these scores may help the interventional cardiologist to prepare for procedural complications during pPCI. (Anatol J Cardiol 2017; 17: 276-84)

Effect of collaterals on deaths and re-infarctions in patients with coronary artery disease: a meta-analysis

BACKGROUND

It is generally believed that there is a beneficial effect of collaterals on death and re-infarction statistics in patients with coronary artery disease (CAD) but studies to date are small and inconsistent.

OBJECTIVE

To meta-analyse the studies published in this field in order to obtain more powerful information.

METHODS

We searched Medline and major journals (2000 to 2011) for studies evaluating the effect of coronary collaterals on mortality. Publication bias, lack of heterogeneity, and lack of robustness were assessed using the standard procedures for such purposes.

RESULTS

A total of 10 studies describing mortality, enrolling 6791 participants, were included in this analysis. In patients with collateralisation a significant relation with reduced mortality was seen compared with those without collateralisation, at an odds ratio of 0.47, p < 0.0001, and a reduction in deaths and re-infarctions at 0.54, p < 0.0001. Some publication bias, some heterogeneity and some lack of robustness were demonstrated. A meta-regression with the odds ratios of the presence of traditional atherosclerotic risk factors as predictors and the odds ratios of mortality and the composite deaths and re-infarctions as outcome showed no relationships.

CONCLUSIONS

In CAD patients from the post-percutaneous coronary intervention era the presence of collaterals reduced mortality by 0.47 (p < 0.0001) and deaths and re-infarctions by 0.54 (p < 0.0001). Furthermore, in the present meta-data, the atherosclerotic risk factors were no more present in patients with collaterals than they were in those without.

A no-reflow prediction model in patients with ST-elevation acute myocardial infarction and primary drug-eluting stenting

OBJECTIVES

This study was undertaken to assess independent no-reflow predictors in patients with ST-elevation acute myocardial infarction (STEMI) and primary drug-eluting stenting in the current interventional strategies.

DESIGN

One thousand four hundred and thirteen patients with STEMI were successfully treated with primary drug-eluting stenting within 12 h after AMI. All clinical, angiographic and procedural data were collected. Univariate and multivariate logistic regression was used to identify independent no-reflow predictors.

RESULTS

The no-reflow was found in 297 (21%) of 1413 patients. Univariate and multivariate logistic regression identified that age (>65 years, OR 1.47, 95% CI 1.46-1.49; p = 0.007), long time-to-reperfusion (>6 h, OR 1.27, 95% CI 1.16-1.40; p = 0.001), admission plasma glucose (>13.0 mmol/L, OR 1.27, 95% CI 1.16-1.40; p = 0.027), collateral circulation (0-1, OR 1.69, 95% CI 1.25-2.29; p = 0.001), pre-PCI thrombus score (≥4, OR 1.36, 95% CI 1.16-1.79; p = 0.011), and IABP use before PCI (OR 2.89, 95% CI 1.65-5.05; p < 0.0001) were independent no-reflow predictors. The no-reflow rate significantly increased as the number of independent predictors increased (0%, 6%, 15%, 25%, 40%, 50% and 100% in patients with 0, 1, 2, 3, 4, 5, and 6 independent predictors, respectively; p < 0.0001).

CONCLUSIONS

The prediction model consisted of six no-reflow predictors in patients with STEMI and primary drug-eluting stenting and should be confirmed in large-scale prospective studies.

Effect of coronary collaterals on long-term prognosis in patients undergoing primary angioplasty for acute ST-elevation myocardial infarction

The aim of this study was to examine the effect of coronary collateral flow before reperfusion on long-term clinical prognosis in patients with acute ST-elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention. We studied 235 patients with STEMI within 12 hours after symptom onset. All patients had Thrombolysis In Myocardial Infarction grade < or =1 flow before percutaneous coronary intervention. Collateral flow was graded according to the Rentrop classification. Patients were categorized as having absent or poor collateral flow to the infarct-related artery (group A) or significant flow (group B). In 166 patients there was absent or weak collateral flow (group A), whereas 69 had significant flow (group B). Long-term follow-up was available in 227 patients (97%) at a median of 797 days. Overall, 25 patients died during the follow-up period, 22 patients (13.8%) in group A and 3 patients (4.4%) in group B (p = 0.04). A total of 12 (7.5%) nonfatal recurrent myocardial infarctions occurred in group A compared to 2 (2.9%) in group B (p = 0.18). The combined major adverse cardiovascular event end point (death or nonfatal reinfarction) showed a significantly lower event rate in group B (p = 0.02). Extensive collateral flow at baseline was a significant predictor for a favorable long-term clinical outcome on multivariable analysis after adjustment for established prognostic markers. In conclusion, the presence of a well-developed collateral network before mechanical reperfusion in patients with STEMI is associated with improved long-term survival and lower major adverse cardiovascular event rates.