Impact of symptom-to-reperfusion-time on transmural infarct extent and left ventricular strain in patients with ST-segment elevation myocardial infarction: a 3D view on the wavefront phenomenon.

AIMS: We examined the association between the symptom-to-reperfusion-time and cardiovascular magnetic resonance (CMR)-derived global strain parameters and transmural infarct extent in ST-segment elevation myocardial infarction (STEMI) patients. METHODS AND RESULTS: The study included 108 STEMI patients who underwent successful primary percutaneous coronary intervention (PPCI). Patients were categorized according to the median symptom-to-reperfusion-time: shorter (<160 min, n = 54) and longer times (>160 min, n = 54). CMR was performed 2-7 days after PPCI and at 1 month. CMR cine imaging was performed for functional assessment and late gadolinium enhancement to evaluate transmural infarct extent. Myocardial feature-tracking was used for strain analysis. Groups were comparable in relation to incidence of LAD disease and pre- and post-PPCI thrombolysis in myocardial infarction (TIMI) flow grades. The mean transmural extent score at follow-up was lower in patients with shorter reperfusion time (P < 0.01). Both baseline and follow-up maximum transmural extent scores were smaller in patients with shorter reperfusion time (P = 0.03 for both). Patients with shorter reperfusion time had more favourable global left ventricular (LV) circumferential strain (baseline, P = 0.049; follow-up, P = 0.01) and radial strain (baseline, P = 0.047; follow-up, P < 0.01), whilst LV longitudinal strain appeared comparable for both baseline and follow-up (P > 0.05 for both). In multi-variable regression analysis including all three strain directions, baseline LV circumferential strain was independently associated with the mean transmural extent score at follow-up (ß=1.89, P < 0.001). CONCLUSION: In STEMI patients, time-to-reperfusion was significantly associated with smaller transmural extent of infarction and better LV circumferential and radial strain. Moreover, infarct transmurality and residual LV circumferential strain are closely linked.

Characterizing Fast and Slow Progressors in Anterior Circulation Large Vessel Occlusion Strokes.

BACKGROUND AND PURPOSE: Infarct growth rate (IGR) in acute ischemic stroke is highly variable. We sought to evaluate impact of symptom-reperfusion time on outcomes in patients undergoing mechanical thrombectomy (MT). METHODS: A prospectively maintained database from January,2012-August,2020 was reviewed. All patients with isolated MCA-M1 occlusion who achieved complete reperfusion(mTICI2C-3), had a witnessed symptom onset and follow-up MRI were included. IGR was calculated as final infarct volume (FIV)(ml)/symptom onset to reperfusion time(hours) and was dichotomized according to the median value into slow-(SP) versus fast-progressors (FP). The primary analysis aimed to evaluate the impact of symptom-reperfusion time on 90-day mRS in SP and FP. Secondary analysis was performed to identify predictors of IGR. RESULTS: A total of 137 patients were eligible for analysis. Mean age was 63 ± 15.4 years and median IGR was 5.13ml/hour. SP(n = 69) had higher median ASPECTS, lower median rCBF<30% lesion volume, higher proportion of favorable collaterals and hypoperfusion intensity ratio (HIR)<0.4, higher minimal mean arterial blood pressure before reperfusion, and lower rates of general anesthesia compared to FP(n = 68). Symptom-reperfusion time was comparable between both groups. SP had higher rates of 90-day mRS0-2(71.9%vs.38.9%,aOR;7.226,95%CI[2.431-21.482],p < 0.001) and lower median FIV. Symptom-reperfusion time was associated with 90-day mRS0-2 in FP (aOR;0.541,95%CI[0.309-0.946],p = 0.03) but not in SP (aOR;0.874,95%CI[0.742-1.056],p = 0.16). On multivariable analysis, high ASPECTS and favorable collaterals in the NCCT/CTA model, and low rCBF<30% and HIR<0.4 in the CTP model were independent predictors of SP. CONCLUSIONS: The impact of symptom-reperfusion time on outcomes significantly varies across slow-versus fast-progressors. ASPECTS, collateral score, rCBF<30%, and HIR define stroke progression profile.

Time Is Kidney: Relation between Pain-to-Balloon Time and Acute Kidney Injury among ST Segment Elevation Patients Undergoing Primary Percutaneous Intervention.

BACKGROUND: Among ST segment elevation myocardial infarction (STEMI), early hemodynamic changes may result in acute kidney injury (AKI) even prior to primary percutaneous coronary intervention (PCI); however, no information to date is present regarding the association between pain-to-balloon time (PBT) and AKI. We evaluated whether PBT predicts the risk of AKI among STEMI patients undergoing primary PCI. METHODS: Medical records of 2,343 STEMI patients undergoing primary PCI were reviewed. Patients were stratified by PBT into 3 groups: ≤120, 121-360, and >360 min. Patients' records were assessed for the occurrence of AKI (defined by the KDIGO criteria as serum creatinine (sCr) elevation ≥0.3 mg/dL within 72 h after admission). RESULTS: Mean age was 61 ± 13 years, and 1,919 (82%) were male. Patients having longer PBT had more AKI complicating the course of STEMI (7% vs. 8% vs. 13%, p < 0.001) and had significantly higher sCr changes throughout hospitalization (0.08 mg/dL vs. 0.11 mg/dL vs. 0.17 mg/dL p < 0.001). In a multivariable logistic regression model, each 1-h increase in PBT was independently associated with a 2.2% increase in risk for AKI (odds ratio 1.022, 95% confidence interval: 1.01-1.04, p = 0.02). CONCLUSION: Longer PBT may be an independent marker for the development of AKI in STEMI patients undergoing primary.

Leukocytes in Cerebral Thrombus Respond to Large-Vessel Occlusion in a Time-Dependent Manner and the Association of NETs With Collateral Flow.

Thrombus components are dynamically influenced by local blood flow and blood immune cells. After a large-vessel occlusion stroke, changes in the cerebral thrombus are unclear. Here we assessed a total of 206 cerebral thrombi from patients with ischemic stroke undergoing endovascular thrombectomy. The thrombi were categorized by time to reperfusion of <4 h (T4), 4-8 h (T4-8), and >8 h (T8). The cellular compositions in thrombus were analyzed, and relevant clinical features were compared. Both white blood cells and neutrophils were increased and then decreased in thrombus with time to reperfusion, which were positively correlated with those in peripheral blood. The neutrophil extracellular trap (NET) content in thrombus was correlated with the degree of neurological impairment of patients. Moreover, with prolonged time to reperfusion, the patients showed a trend of better collateral grade, which was associated with a lower NET content in the thrombus. In conclusion, the present results reveal the relationship between time-related endovascular immune response and clinical symptoms post-stroke from the perspective of thrombus and peripheral blood. The time-related pathological changes of cerebral thrombus may not be the direct cause for the difficulty in thrombolysis and thrombectomy. A low NET content in thrombi indicates excellent collateral flow, which suggests that treatments targeting NETs in thrombi might be beneficial for early neurological protection.

Outcome, efficacy and safety of endovascular thrombectomy in ischaemic stroke according to time to reperfusion: data from a multicentre registry.

BACKGROUND AND PURPOSE: In acute ischaemic stroke (AIS) of the anterior circulation (AC) treated with mechanical thrombectomy (MT), data point to a decline of treatment effect with increasing time from symptom onset to treatment. However, the magnitude of the decline will depend on the clinical setting and imaging selection used. The aims of this study were (1) to evaluate the clinical effect of time to reperfusion (TTR); and (2) to assess the safety and technical efficacy of MT according to strata of TTR. METHODS: Using the retrospective multicentre BEYOND-SWIFT registry data (ClinicalTrials.gov identifier: NCT03496064), we compared safety and efficacy of MT in 1461 patients between TTR strata of 0-180 min (n = 192), 180-360 min (n = 876) and >360 min (n = 393). Clinical effect of TTR was evaluated using multivariable logistic regression analyses adjusting for pre-specified confounders [adjusted odds ratios (aOR) and 95% confidence intervals (95% CI)]. Primary outcome was good functional outcome (modified Rankin Scale: mRS 0-2) at day 90. RESULTS: Every hour delay in TTR was a significant factor related to mRS 0-2 (aOR 0.933, 95% CI 0.887-0.981) with an estimated 1.5% decreased probability of good functional outcome per hour delay of reperfusion, and mRS 0-1 (aOR 0.929, 95% CI 0.877-0.985). Patients with late TTR had lower rates of successful and excellent reperfusion, higher complication rates and number of passes. CONCLUSIONS: TTR is an independent factor related to long-term functional outcome. With increasing TTR, interventional procedures become technically less effective. Efforts should be made to shorten TTR through optimized prehospital and in-hospital pathways.

Clinical Outcome After Mechanical Thrombectomy in Patients with Diabetes with Major Ischemic Stroke of the Anterior Circulation.

BACKGROUND: Among patients with acute ischemic stroke treated with mechanical thrombectomy (MT), patients with diabetes (DP) show a poorer outcome compared with patients without diabetes (NDP). This study aims to provide a comprehensive analysis of factors associated with unfavorable outcome in DP receiving MT for stroke of the anterior circulation. METHODS: This study included 317 of 498 consecutive patients who received interventional treatment for acute ischemic stroke in the terminal internal carotid artery and/or middle cerebral artery, including 46 DP. The study data included pre- and posttreatment stroke computed tomography, including perfusion data, collateral status, treatment data including treatment times, pre-existing cardiovascular risk factors, cerebrovascular events, comorbidities, laboratory parameters, and medication. Neurologic status was assessed at baseline (National Institute of Health Stroke Scale [NIHSS]/modified Rankin Scale [mRS]) and after 90 days (mRS 90). RESULTS: Compared with NDP, DP showed a significantly poorer outcome (mRS90 >2) (P < 0.05). Collateralization and infarct core size did not differ between groups, whereas the penumbra was significantly smaller in DP than in NDP (P < 0.05). The poorer mRS90 outcome (mRS90 > 2) in DP was associated with poor collaterals (P = 0.01) and hyperglycemia on admission (P < 0.05). Shorter time to reperfusion was associated with favorable mRS90 in the NDP (P < 0.001) but not the DP (P = 0.49) group. In univariate logistic regression, the following parameters were significantly associated with mRS90: diabetes, hyperglycemia at admission, time to reperfusion, and the NIHSS score (P < 0.05 each). In multivariate analyses and partition regression models of all variables, DP with admission hyperglycemia (≥132 mg/dL) and older age (≥66 years) showed a particularly poor outcome. CONCLUSIONS: The main factors for an unfavorable outcome of DP after MT are admission hyperglycemia, age, and NIHSS score.