One-year results from the Assessing MICRO-vascular resistances via IMR to predict outcome in ST-elevation myocardial infarction patients with multivessel disease undergoing primary PCI (AMICRO) trial.

Background: In ST-elevation myocardial infarction (STEMI) patients undergoing primary percutaneous coronary angioplasty (PPCI) the index of microcirculatory resistance (IMR) correlates to the extent of myocardial damage and left ventricular (LV) function recovery. Data on the IMR time-course and impact on clinical outcome in STEMI patients with multi-vessel disease (MVD) are scarce. Aims: We designed a prospective, multicenter clinical trial to assess the infarct-related artery (IRA)-IMR in STEMI patients with MVD undergoing PPCI and to explore its potential in relationship with outcome and LV remodeling. Methods: The study enrolled 242 STEMI patients with MVD. Both fractional flow reserve (FFR) and IMR of the IRA were assessed after successful PPCI. Then, FFR/IMR measurements were repeated in the IRA at a staged angiography, and FFR-guided angioplasty was performed in non-IRA lesions. The primary endpoint was the composite of cardiovascular death, re-infarction, re-hospitalization for heart failure, resuscitation or appropriate ICD shock at 1-year follow-up. Results: A significant improvement of IRA-IMR values (from 47.9 to 34.2, p < 0.0001) was observed early after PPCI. Staged FFR-guided angioplasty was performed in 102 non-IRA lesions. We failed to find a correlation between IRA-IMR, clinical events and LV remodeling. Notwithstanding, in patients with anterior STEMI an inverse correlation between initial IMR values and LV function at follow-up was observed. Conclusion: After successful PPCI, a significant proportion of patients with STEMI and MVD had coronary microvascular dysfunction as assessed by IMR that recovered early after reperfusion. Higher IMR values predicted lack of improvement of LV function only in anterior STEMI. Clinical trial registration: https://clinicaltrials.gov/, identifier [NCT02325973].

Prognostic Value of QFR Measured Immediately After Successful Stent Implantation: The International Multicenter Prospective HAWKEYE Study.

OBJECTIVES: The aim of this study was to investigate the potential role of post-percutaneous coronary intervention (PCI) quantitative flow ratio (QFR) measurements to predict clinical outcomes in patients with successful PCI. BACKGROUND: The prognostic value of QFR measured immediately after PCI has not been prospectively investigated. METHODS: Patients undergoing complete revascularization with successful PCI and stent implantation were eligible for acquisition of projections for QFR computation. At the end of the procedure, 2 angiographic projections for each vessel treated with PCI were acquired. Computation of QFR was performed offline by an independent core laboratory. The primary outcome was the vessel-oriented composite endpoint, defined as vessel-related cardiovascular death, vessel-related myocardial infarction, and ischemia-driven target vessel revascularization. RESULTS: Seven hundred fifty-one vessels in 602 patients were analyzed. The median value of post-PCI QFR was 0.97 (interquartile range: 0.92 to 0.99). Lesion location in the left anterior descending coronary artery, baseline SYNTAX (Synergy Between PCI With Taxus and Cardiac Surgery) score, lesion length, and post-PCI diameter stenosis were found to be predictors of lower post-PCI QFR. Altogether, 77 events were detected in 53 treated vessels (7%). Post-PCI QFR was significantly lower in vessels with the vessel-oriented composite endpoint during follow-up, compared with those without it (0.88 [interquartile range: 0.81 to 0.99] vs. 0.97 [interquartile range: 0.93 to 0.99], respectively; p < 0.001). Receiver-operating characteristic curve analysis identified a post-PCI QFR best cutoff of ≤0.89 (area under the curve 0.77; 95% confidence interval: 0.74 to 0.80; p < 0.001). After correction for potential confounding factors, post-PCI QFR ≤0.89 was associated with a 3-fold increase in risk for the vessel-oriented composite endpoint (hazard ratio: 2.91; 95% confidence interval: 1.63 to 5.19; p < 0.001). CONCLUSIONS: Lower values of QFR after complete and successful revascularization predict subsequent adverse events (Angio-Based Fractional Flow Reserve to Predict Adverse Events After Stent Implantation [HAWKEYE]; NCT02811796).

Assessing MICRO-vascular resistances via IMR to predict outcome in STEMI patients with multivessel disease undergoing primary PCI (AMICRO): Rationale and design of a prospective multicenter clinical trial.

BACKGROUND: In STEMI patients treated with primary percutaneous coronary angioplasty (PPCI) the evaluation of coronary microcirculatory resistance index (IMR) predict the extent of microvascular damage and left ventricular (LV) remodeling. However, the impact of IMR on the clinical outcome after PPCI in patients with multivessel disease (MVD) remains unsettled. AIM: We designed a prospective multicenter controlled clinical trial to evaluate the prognostic value of IMR in terms of clinical outcome and left ventricular remodeling in STEMI patients with MVD undergoing PPCI. METHODS AND DESIGN: The study will involve 242 patients with MVD defines as the presence of at least a non-culprit lesion of >50% stenosis at index coronary angiography. Both fractional flow reserve (FFR) and IMR will be measured in the infarct-related artery (IRA) after successful PPCI. Measurements of FFR and IMR will be repeated in the IRA and performed in the non-culprit vessels at staged angiography. The non-culprit vessel lesions will be treated only in the presence of a FFR<0.75. A 2D echocardiographic evaluation of the left ventricular (LV) volumes and ejection fraction will be performed before hospital discharge and at 1-year follow-up. The primary end-point of the study will be the composite of cardiovascular death, re-hospitalization for heart failure and resuscitation or appropriate ICD shock during 1-year of follow-up. Secondary end-points will be the impact of IMR in predicting LV remodeling during follow-up and correlations between IMR and ST-segment resolution. Other secondary endpoints will be need for new revascularization, stent thrombosis and re-infarction of the non-culprit vessels territory. IMPLICATIONS: If IMR significantly correlates with differences in outcome and LV remodeling, it will emerge as a potential prognostic index after PPCI in patients with MVD.

Culotte bifurcation stenting with paclitaxel drug-eluting stent.

The results of using the culotte bifurcation technique have not been promising with regard to bare metal stents; however, some possible advantages with regard to drug-eluting stents (DES) must be taken into account, such as the possibility to stent provisionally, to use lower French sizes, and to completely cover the coronary wall and the new carina with a single or double stent layer. The crush technique, which aims to reach a complete coverage of the coronary wall to allow antiproliferative drugs to homogeneously distribute into the coronary walls, has been introduced. The culotte technique seems to act more physiologically, allowing the creation of a new, homogeneously covered carina, without any crushed metal inside the coronary wall. We present the case of a coronary bifurcation treated with the use of the culotte technique and paclitaxel-eluting stent deployment, with good angiographic results after 10 months of follow-up. Further data are needed to evaluate the potential utility of the culotte technique in treating bifurcation coronary lesions in the area of DES.

Simultaneous double-culprit in-stent thrombosis. Who is the guilty prisoner behind bars: drug-eluting stent, bare-metal stent, or indication for treatment?

BACKGROUND: The intrinsic thrombogeneity of stents was the historic limitation to their usage during the early phases of stenting. The risk of stent thrombosis has been minimized by the widespread use of platelet antiaggregation. Nowadays, the risk of subacute stent thrombosis is around 1%. Thrombotic risk depends on several factors, such as type of stent, complexity of lesion, and clinical picture. CASE REPORT: We present a case of recurrent acute in-stent thrombosis in a patient with mild antithrombin III (AT) deficiency despite the combined administration of clopidogrel and aspirin. CONCLUSION: In our patient, several factors, such as diabetes, AT deficiency, and the use of a paclitaxel-eluting stent, have contributed to the development of recurrent acute stent thrombosis. Although we were not able to identify the culprit factor, we should keep in mind that the deployment of a drug-eluting stent could be unsafe if it is not supported by a clear clinically oriented pathway that considers the overall condition of the patient since, in some cases, neither coronary lesions nor coronary stents are responsible for the negative outcome of patient therapy, which may be caused instead by incomplete or inadequate patient assessment.