Browsing by Author "Ostojic, Miodrag (34572650500)"

Background: Insulin resistance (IR) assessed by the Homeostatic Model Assessment (HOMA) index in the acute phase of myocardial infarction in non-diabetic patients was recently established as an independent predictor of intrahospital mortality. In this study we postulated that acute IR is a dynamic phenomenon associated with the development of myocardial and microvascular injury and larger final infarct size in patients with ST-segment elevation myocardial infarction (STEMI) treated by primary percutaneous coronary intervention (pPCI).Methods: In 104 consecutive patients with the first anterior STEMI without diabetes, the HOMA index was determined on the 2nd and 7th day after pPCI. Worst-lead residual ST-segment elevation (ST-E) on postprocedural ECG, coronary flow reserve (CFR) determined by transthoracic Doppler echocardiography on the 2nd day after pPCI and fixed perfusion defect on single-photon emission computed tomography myocardial perfusion imaging (SPECT-MPI) determined six weeks after pPCI were analyzed according to HOMA indices.Results: IR was present in 55 % and 58 % of patients on day 2 and day 7, respectively. Incomplete post-procedural ST-E resolution was more frequent in patients with IR compared to patients without IR, both on day 2 (p = 0.001) and day 7 (p < 0.001). The HOMA index on day 7 correlated with SPECT-MPI perfusion defect (r = 0.331), whereas both HOMA indices correlated well with CFR (r = -0.331 to -0.386) (p < 0.01 for all). In multivariable backward logistic regression analysis adjusted for significant univariate predictors and potential confounding variables, IR on day 2 was an independent predictor of residual ST-E ≥ 2 mm (OR 11.70, 95% CI 2.46-55.51, p = 0.002) and CFR < 2 (OR = 5.98, 95% CI 1.88-19.03, p = 0.002), whereas IR on day 7 was an independent predictor of SPECT-MPI perfusion defect > 20% (OR 11.37, 95% CI 1.34-96.21, p = 0.026).Conclusion: IR assessed by the HOMA index during the acute phase of the first anterior STEMI in patients without diabetes treated by pPCI is independently associated with poorer myocardial reperfusion, impaired coronary microcirculatory function and potentially with larger final infarct size. © 2014 Trifunovic et al.; licensee BioMed Central Ltd.

This study evaluated additive prognostic value of the SYNTAX score over GRACE, TIMI, ZWOLLE, CADILLAC and PAMI risk scores in patients with STsegment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (pPCI). All six scores were calculated in 209 consecutive STEMI patients undergoing pPCI. Primary end-point was the major adverse cardiovascular event (MACE-composite of cardiovascular mortality, non-fatal myocardial infarction and stroke); secondary end point was cardiovascular mortality. Patients were stratified according to the SYNTAX score tertiles (≤12; between 12 and 19.5; >19.5). The median follow-up was 20 months. Rates of MACE and cardiovascular mortality were highest in the upper tertile of the SYNTAX score (p<0.001 and p = 0.003, respectively). SYNTAX score was independent multivariable predictor of MACE and cardiovascular mortality when added to GRACE, TIMI, ZWOLLE, and PAMI risk scores. However, the SYNTAX score did not improve the Cox regression models of MACE and cardiovascular mortality when added to the CADILLAC score. The SYNTAX score has predictive value for MACE and cardiovascular mortality in patients with STEMI undergoing primary PCI. Furthermore, SYNTAX score improves prognostic performance of well-established GRACE, TIMI, ZWOLLE and PAMI clinical scores, but not the CADILLAC risk score. Therefore, long-term survival in patients after STEMI depends less on detailed angiographical characterization of coronary lesions, but more on clinical characteristics, myocardial function and basic angiographic findings as provided by the CADILLAC score.

Introduction: Results of currently available trials have shown divergent outcomes in diabetic patients undergoing percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG). Current guidelines do not recommend PCI in patients with diabetes and a SYNTAX score ≥ 23. Aim: To compare all-cause 4-year mortality after revascularization for complex coronary artery disease (CAD) in diabetics. Material and methods: The study group comprised consecutive patients with three-vessel CAD and/or unprotected left main CAD (≥ 50% diameter stenosis) without major hemodynamic instability, who were treated in two institutions with PCI or referred for CABG. Results: Out of 342 diabetics, 177 patients underwent PCI and 165 patients were referred for CABG. The incidence of all-cause death was different between diabetics treated with PCI or CABG at 4 years (16/177, 9.0% vs. 26/165, 15.8%, respectively, p = 0.03). The difference was not evident in non-diabetics (PCI: 41/450, 9.1% vs. CABG: 19/249, 7.6%, p = 0.173). In diabetics, there was a higher incidence of all-cause mortality in PCI patients with intermediate-high (≥ 23) SYNTAX scores compared with those with low (0–22) SYNTAX scores (10/56, 17.9% vs. 6/121, 5.0%, respectively, p < 0.01). On the other hand, diabetics who underwent CABG showed similar mortality rates irrespective of the SYNTAX scores (SYNTAX 0–22: 3/29, 10.3%; SYNTAX ≥ 23: 23/136, 11.9%, p = 0.46). In the subgroup analysis, there was no interaction according to presence or absence of left main CAD (p for interaction = 0.12) as well as according to diabetes status (p for interaction = 0.38), whereas gender and SYNTAX scores were differentiators between PCI and CABG with a p for interaction < 0.1. Conclusions: Our analysis supports recent evidence that diabetes is not a differentiator between PCI and CABG. © 2020 Termedia Publishing House Ltd.. All rights reserved.

Background/objectives The SYNTAX Score II (SSII) was proposed as a novel approach for objective individualized decision-making for optimal myocardial revascularization i.e. percutaneous coronary intervention (PCI) or coronary artery bypass graft (CABG) surgery. We sought to investigate how many lives may be saved by SSII use. Methods A total number of 651 consecutive SSII-naive-patients with complex coronary artery disease who were treated with PCI (n = 409) or referred to other institutions for CABG (n = 242) were included. All-cause mortality was ascertained in 96% of patients. The SSII was calculated for each patient. Results Based on the SSII treatment recommendation, CABG would have been the treatment of choice in 257/651 (39.5%) patients, PCI in 7/651 (1.1%) patients and CABG or PCI in 387/651 (59.4%) patients. Out of 257 patients in whom the treatment recommendation by SSII was CABG, 113/257 (44.0%) patients had actually CABG, while the remaining 144/257 (56.0%) underwent PCI. It was shown that 144/257 patients with treatment recommendations in favour of CABG who were treated with PCI had significantly higher mortality at 4 years when compared with patients with SSII treatment recommendation for PCI or equally favouring CABG and PCI (12.5% vs. 0.0% vs. 6.9%, respectively, P = 0.04). Conclusion The intuitive decision-making for choosing the optimal myocardial revascularization method differed predominantly from the SSII recommendation for CABG. The discordance between the SSII recommended revascularization strategy and the clinical decision was associated with a higher 4-year mortality i.e. one life may be saved if SSII would be calculated and followed consequently in 18 patients. © 2016 Elsevier Ireland Ltd

Objectives This study sought to evaluate the feasibility and safety of autologous bone marrow-derived and cardiogenically oriented mesenchymal stem cell therapy and to probe for signs of efficacy in patients with chronic heart failure. Background In pre-clinical heart failure models, cardiopoietic stem cell therapy improves left ventricular function and blunts pathological remodeling. Methods The C-CURE (Cardiopoietic stem Cell therapy in heart failURE) trial, a prospective, multicenter, randomized trial, was conducted in patients with heart failure of ischemic origin who received standard of care or standard of care plus lineage-specified stem cells. In the cell therapy arm, bone marrow was harvested and isolated mesenchymal stem cells were exposed to a cardiogenic cocktail. Derived cardiopoietic stem cells, meeting release criteria under Good Manufacturing Practice, were delivered by endomyocardial injections guided by left ventricular electromechanical mapping. Data acquisition and analysis were performed in blinded fashion. The primary endpoint was feasibility/safety at 2-year follow-up. Secondary endpoints included cardiac structure/function and measures of global clinical performance 6 months post-therapy. Results Mesenchymal stem cell cocktail-based priming was achieved for each patient with the dose attained in 75% and delivery without complications in 100% of cases. There was no evidence of increased cardiac or systemic toxicity induced by cardiopoietic cell therapy. Left ventricular ejection fraction was improved by cell therapy (from 27.5 ± 1.0% to 34.5 ± 1.1%) versus standard of care alone (from 27.8 ± 2.0% to 28.0 ± 1.8%, p < 0.0001) and was associated with a reduction in left ventricular end-systolic volume (-24.8 ± 3.0 ml vs. -8.8 ± 3.9 ml, p < 0.001). Cell therapy also improved the 6-min walk distance (+62 ± 18 m vs. -15 ± 20 m, p < 0.01) and provided a superior composite clinical score encompassing cardiac parameters in tandem with New York Heart Association functional class, quality of life, physical performance, hospitalization, and event-free survival. Conclusions The C-CURE trial implements the paradigm of lineage guidance in cell therapy. Cardiopoietic stem cell therapy was found feasible and safe with signs of benefit in chronic heart failure, meriting definitive clinical evaluation. (C-Cure Clinical Trial; NCT00810238). © 2013 by the American College of Cardiology Foundation.

Introduction: Angiogenesis is the growth of both new vascular and lymphatic blood vessels from the existing vasculature. During this process, blood endothelial cells (BECs) and lymphatic endothelial cells (LECs) express specific markers, which help their discrimination and easier identification. Since the coronary thrombi material aspirated from patients with ST-elevation myocardial infarction (STEMI) proved as good angiogenesis model, we investigated the expression of CD34 and CD31 as BECs markers, and D2-40, LYVE-1 and VEGFR3 as LEC markers in this material. Materials and methods: Aspirated thrombi were stained immunohistochemically for CD34, CD31, D2-40, LYVE-1 and VEGFR3. Organizational patterns of immunopositive cells were graded as single cells, clusters or microvessels. Double immunofluorescence for CD31, D2-40, LYVE-1 and VEGRF3 was done. Thrombi were also graded as fresh (< 1 day old), lytic (1-5 days old) and organized (> 5 days old). Results: Serial sections of aspirated thrombi showed concordant BEC and LEC markers immunopositivity. Double immunoflorescence proved co-expression of CD31 and LEC markers on the same cells. Cells expressing LEC markers organized in clusters and microvessels were mainly present in lytic and organized thrombi. Conclusion: Co-expression of BEC and LEC markers on the same non-tumorous cell during thrombus neovascularization indicates existing in vivo plasticity of endothelial cells under non-tumorous pathological conditions. It also points that CD34 and CD31 on one hand, and D2-40, LYVE-1 and VEGFR3 immunostaining on the other hand, cannot solely be a reliable indicators whether vessel is lymphatic or not. © 2015 Elsevier Inc.

Introduction: Angiogenesis is the growth of both new vascular and lymphatic blood vessels from the existing vasculature. During this process, blood endothelial cells (BECs) and lymphatic endothelial cells (LECs) express specific markers, which help their discrimination and easier identification. Since the coronary thrombi material aspirated from patients with ST-elevation myocardial infarction (STEMI) proved as good angiogenesis model, we investigated the expression of CD34 and CD31 as BECs markers, and D2-40, LYVE-1 and VEGFR3 as LEC markers in this material. Materials and methods: Aspirated thrombi were stained immunohistochemically for CD34, CD31, D2-40, LYVE-1 and VEGFR3. Organizational patterns of immunopositive cells were graded as single cells, clusters or microvessels. Double immunofluorescence for CD31, D2-40, LYVE-1 and VEGRF3 was done. Thrombi were also graded as fresh (< 1 day old), lytic (1-5 days old) and organized (> 5 days old). Results: Serial sections of aspirated thrombi showed concordant BEC and LEC markers immunopositivity. Double immunoflorescence proved co-expression of CD31 and LEC markers on the same cells. Cells expressing LEC markers organized in clusters and microvessels were mainly present in lytic and organized thrombi. Conclusion: Co-expression of BEC and LEC markers on the same non-tumorous cell during thrombus neovascularization indicates existing in vivo plasticity of endothelial cells under non-tumorous pathological conditions. It also points that CD34 and CD31 on one hand, and D2-40, LYVE-1 and VEGFR3 immunostaining on the other hand, cannot solely be a reliable indicators whether vessel is lymphatic or not. © 2015 Elsevier Inc.

Coronary microcirculatory function after primary percutaneous coronary intervention (pPCI) in patients with acute myocardial infarction is important determinant of infarct size (IS). Our aim was to investigate the utility of coronary flow reserve (CFR) and diastolic deceleration time (DDT) of the infarct artery (IRA) assessed by transthoracic Doppler echocardiography after pPCI for final IS prediction. In 59 patients, on the 2nd day after pPCI for acute anterior myocardial infarction, transthoracic Doppler analysis of IRA blood flow was done including measurements of CFR, baseline DDT and DDT during adenosine infusion (DDT adeno). Killip class, myocardial blush grade, resolution of ST segment elevation, peak creatine kinase-myocardial band and conventional echocardiographic parameters were determined. Single-photon emission computed tomography myocardial perfusion imaging was done 6 weeks later to define final IS (percentage of myocardium with fixed perfusion abnormality). IS significantly correlated with CFR (r = −0.686, p < 0.01), DDT (r = −0.727, p < 0.01), and DDT adeno (r = −0.780, p < 0.01). CFR and DDT adeno in multivariate analysis remained independent IS predictors after adjustment for other covariates and offered incremental prognostic value in models based on conventional clinical, angiographic, electrocardiographic and enzymatic variables. In predicting large infarction (IS > 20 %), the best cut-off for CFR was <1.73 (sensitivity 65 %, specificity 96 %) and for DDT adeno ≤720 ms (sensitivity 81 %, specificity 96 %). CFR and DDT during adenosine are independent and powerful early predictors of final IS offering incremental prognostic information over conventional parameters of myocardial and microvascular damage and tissue reperfusion. © 2014, Springer Science+Business Media Dordrecht.

[No abstract available]

Background: No comprehensive primary PCI (pPCI) risk model to predict net adverse cardiovascular events (NACE) has been reported with the use of clopidogrel 600 mg, which is now considered the standard loading dose. The primary hypothesis of the RISK-PCI trial is that an accurate risk prediction may be achieved by using clinical, angiographic, and procedural variables available at the time of intervention. Methods: The present single-center, longitudinal, cohort study will include 1,750 consecutive patients with ST-elevation myocardial infarction (STEMI), undergoing pPCI after pretreatment with 300 mg aspirin and 600 mg clopidogrel. The primary end-points of the trial (NACE) include major adverse cardiovascular events (MACE) and major bleeding. A logistic regression model will be developed to predict 30-day and 1-year NACE after pPCI. A risk score derived from study set data will be validated using validation set data. Results: Until June 1, 2008, 1,166 patients have been enrolled. Thirty-day follow-up is available in 1,007 patients. Conclusions: The RISK-PCI study is designed to develop an accurate risk scoring system, using variables available at the time of intervention, to predict long-term adverse outcomes after pPCI. Trial Registration: Current Controlled Trials Register - ISRCTN83474650 - http://www.controlled-trials.com/ISRCTN83474650). © 2009, Wiley Periodicals, Inc.

Background: Retrograde approach increases the success rate for percutaneous recanalization of complex chronic total occlusion (CTO) of coronary arteries. Objectives: The purpose of this study was to describe our initial experience of retrograde percutaneous coronary intervention for CTO program, focusing on its safety and feasibility, and long-term clinical follow-up. Methods: The study was a single center retrospective registry which included a total of 40 patients, of 590 CTO treated patients (6.7%), between January 2008 and October 2011, who underwent retrograde approach for CTO recanalization. Results: Mean occlusion duration was 37.8 ± 40.3 months. Overall success recanalization rate was 87.5% (35/40). Septal collaterals were used to access the occlusion in all cases (100%). Retrograde guidewire crossing of collateral channels was successful in 36/40 (90.0%) patients with success rate of CTO recanalization in these patients of 97.2%. Retrograde approach as the primary strategy was applied in 23/40 (57.5%) patients, retrograde approach immediately after antegrade failure attempt was performed in 8/40 (20.0%) patients, and retrograde approach as elective procedure, after previously failed antegrade attempt, was performed in 9/40 (22.5%) patients. The success rate of these strategies was: 87.0% (20/23 patients) for primary, 87.5% (7/8 patients) for retrograde immediately after antegrade failure, and 88.9% (8/9 patients) for retrograde after previous failed antegrade attempt, respectively. Total in-hospital major adverse cardiac events (MACE) rate was 5.0% (2 non-Q-wave myocardial infarctions). The MACE free survival at median follow-up of 20 months was 89% (95% CI: 78-100%). Conclusions: This study has demonstrated that adequate training and international proctorship for this complex and demanding technique is a necessity and prerequisite to achieve high overall success rates, with acceptable complication rates and excellent long-term survival rate. © 2012, Wiley Periodicals, Inc.

Background: Patients in chronic phase of myocardial infarction (MI) have decreased coronary flow reserve (CFR) in infarct related artery (IRA) that is proportional to the extent of microvascular/myocardial damage. We proposed a novel model for the assessment of microvascular damage and infarct size using Doppler echocardiography evaluation of CFRs of the IRA (LAD) and reference artery (RCA). Methods: Our study included 34 consecutive patients (28 men, mean age 50 ± 11 years) with first anterior STEMI and single vessel disease successfully treated with primary PCI. All patients underwent SPECT MPI for the assessment of infarct size (expressed as a percentage of myocardium with fixed perfusion abnormalities) and CFR evaluation of LAD and RCA. CFR derived percentage of microvascular damage (CFR PMD) was calculated as: CFR PMD = (CFR RCA - CFR LAD) / (CFR RCA - 1) × 100 (%). Results: CFR PMD correlated significantly with all parameters evaluating the severity of myocardial damage including: peak CK activity (r = 0.632, p < 0.001), WMSI (r = 0.857, p < 0.001), ejection fraction (r = - 0.820, p < 0.001), left ventricular end diastolic (r = 0.757, p < 0.001) and end systolic volume (r = 0.794, p < 0.001). Most importantly, CFR PMD (22 ± 17%) correlated significantly with infarct size by SPECT MPI (21 ± 17%) (r = 0.874, p < 0.001). Conclusions: CFR PMD derived from the proposed model was significantly related to echocardiographic and enzymatic parameters of infarct size, as well as to myocardial damage assessed by SPECT MPI in patients with successfully reperfused first anterior STEMI. © 2012 Elsevier Ireland Ltd. All rights reserved.

BACKGROUND: Stroke volume response during stress is a major determinant of functional status in heart failure and can be measured by two-dimensional (2-D) volumetric stress echocardiography (SE). The present study hypothesis is that SE may identify mechanisms underlying the change in stroke volume by measuring preload reserve through enddiastolic volume (EDV) and left ventricular contractile reserve (LVCR) with systolic blood pressure and end-systolic volume (ESV). METHODS: We enrolled 4735 patients (age 63.6±11.3 years, 2800 male) referred to SE for known or suspected coronary artery disease (CAD) and/or heart failure (HF) in 21 SE laboratories in 8 countries. In addition to regional wall motion abnormalities (RWMA), force was measured at rest and peak stress as the ratio of systolic blood pressure by cuff sphygmomanometer/ESV by 2D with Simpson's or linear method. Abnormal values of LVCR (peak/rest) based on force were ≤1.10 for dipyridamole (N.=1992 patients) and adenosine (N.=18); ≤2.0 for exercise (N.=2087) or dobutamine (N.=638). RESULTS: Force-based LV CR was obtained in all 4735 patients. Lack of stroke volume increase during stress was due to either abnormal LVCR and/or blunted preload reserve, and 57% of patients with abnormal LVCR nevertheless showed increase in stroke volume. CONCLUSIONS: Volumetric SE is highly feasible with all stresses, and more frequently impaired in presence of ischemic RWMA, absence of viability and reduced coronary flow velocity reserve. It identifies an altered stroke volume response due to reduced preload and/or contractile reserve. © 2020 EDIZIONI MINERVA MEDICA.

BACKGROUND: It is not known whether prehospital fibrinolysis, coupled with timely coronary angiography, provides a clinical outcome similar to that with primary percutaneous coronary intervention (PCI) early after acute ST-segment elevation myocardial infarction (STEMI). METHODS: Among 1892 patients with STEMI who presented within 3 hours after symptom onset and who were unable to undergo primary PCI within 1 hour, patients were randomly assigned to undergo either primary PCI or fibrinolytic therapy with bolus tenecteplase (amended to half dose in patients ≥75 years of age), clopi;dogrel, and enoxaparin before transport to a PCI-capable hospital. Emergency coronary angiography was performed if fibrinolysis failed; otherwise, angiography was performed 6 to 24 hours after randomization. The primary end point was a composite of death, shock, congestive heart failure, or reinfarction up to 30 days. Results The primary end point occurred in 116 of 939 patients (12.4%) in the fibrinolysis group and in 135 of 943 patients (14.3%) in the primary PCI group (relative risk in the fibrinolysis group, 0.86; 95% confidence interval, 0.68 to 1.09; P = 0.21). Emergency angiography was required in 36.3% of patients in the fibrinolysis group, whereas the remainder of patients underwent angiography at a median of 17 hours after randomization. More intracranial hemorrhages occurred in the fibrinolysis group than in the primary PCI group (1.0% vs. 0.2%, P = 0.04; after protocol amendment, 0.5% vs. 0.3%, P = 0.45). The rates of nonintracranial bleeding were similar in the two groups. CONCLUSIONS: Prehospital fibrinolysis with timely coronary angiography resulted in effective reperfusion in patients with early STEMI who could not undergo primary PCI within 1 hour after the first medical contact. However, fibrinolysis was associated with a slightly increased risk of intracranial bleeding. (Funded by Boehringer Ingelheim; ClinicalTrials.gov number, NCT00623623.) Copyright © 2013 Massachusetts Medical Society.

Early experimental and clinical reports on glycogen phosphorylase BB (GPBB) kinetics following myocardial ischemic injury suggested that it could be a useful diagnostic marker for early detection of acute myocardial infarction (AMI). After more than two decades of investigation, there is now overwhelming body of evidence that do not support the use of GPBB measurement in diagnosis of acute AMI in patients presenting with acute chest pain. Currently, GPBB cannot be recommended as a diagnostic marker of AMI either as a stand-alone test or as an addition to (high-sensitive) troponin testing. It should be noted that these considerations apply to the early diagnosis of AMI, not to the prognostic stratification, which is also suggested but it warrants further investigation. The aim of this review is to summarize available evidence of GPBB measurement in early diagnosis of myocardial infarction. © 2014 Elsevier B.V.

Early experimental and clinical reports on glycogen phosphorylase BB (GPBB) kinetics following myocardial ischemic injury suggested that it could be a useful diagnostic marker for early detection of acute myocardial infarction (AMI). After more than two decades of investigation, there is now overwhelming body of evidence that do not support the use of GPBB measurement in diagnosis of acute AMI in patients presenting with acute chest pain. Currently, GPBB cannot be recommended as a diagnostic marker of AMI either as a stand-alone test or as an addition to (high-sensitive) troponin testing. It should be noted that these considerations apply to the early diagnosis of AMI, not to the prognostic stratification, which is also suggested but it warrants further investigation. The aim of this review is to summarize available evidence of GPBB measurement in early diagnosis of myocardial infarction. © 2014 Elsevier B.V.

Background: Glycogen phosphorylase BB (GPBB) is released from cardiac cells during myocyte damage. Previous studies have shown contradictory results regarding the relation of enzyme release and reversible myocardial ischemia. The aim of this study was to determine the plasma kinetics of GPBB as a response to the exercise stress echocardiographic test (ESET), and to define the relationship between myocardial ischemia and enzyme plasma concentrations. Methods: We studied 46 consecutive patients undergoing ESET, with recent coronary angiography. In all patients, a submaximal stress echo test according to Bruce protocol was performed. Concentration of GPBB was measured in peripheral blood that was sampled 5 min before and 10, 30 and 60 min after ESET. Results: There was significant increase of GPBB concentration after the test (p = 0.021). Significant increase was detected 30 min (34.9% increase, p = 0.021) and 60 min (34.5% increase, p = 0.016) after ESET. There was no significant effect of myocardial ischemia on GPBB concentrations (p = 0.126), and no significant interaction between sampling intervals and myocardial ischemia, suggesting a similar release profile of GPBB in ischemic and non-ischemic conditions (p = 0.558). Patients in whom ESET was terminated later (stages 4 or 5 of standard Bruce protocol; n = 13) had higher GPBB concentrations than patients who terminated ESET earlier (stages 1, 2 or 3; n = 33) (p = 0.049). Baseline GPBB concentration was not correlated to any of the patients' demographic, clinical and hemodynamic characteristics. Conclusions: GPBB plasma concentration increases after ESET, and it is not related to inducible myocardial ischemia. However, it seems that GPBB release during ESET might be related to exercise load/duration.

Background: Glycogen phosphorylase BB (GPBB) is released from cardiac cells during myocyte damage. Previous studies have shown contradictory results regarding the relation of enzyme release and reversible myocardial ischemia. The aim of this study was to determine the plasma kinetics of GPBB as a response to the exercise stress echocardiographic test (ESET), and to define the relationship between myocardial ischemia and enzyme plasma concentrations. Methods: We studied 46 consecutive patients undergoing ESET, with recent coronary angiography. In all patients, a submaximal stress echo test according to Bruce protocol was performed. Concentration of GPBB was measured in peripheral blood that was sampled 5 min before and 10, 30 and 60 min after ESET. Results: There was significant increase of GPBB concentration after the test (p = 0.021). Significant increase was detected 30 min (34.9% increase, p = 0.021) and 60 min (34.5% increase, p = 0.016) after ESET. There was no significant effect of myocardial ischemia on GPBB concentrations (p = 0.126), and no significant interaction between sampling intervals and myocardial ischemia, suggesting a similar release profile of GPBB in ischemic and non-ischemic conditions (p = 0.558). Patients in whom ESET was terminated later (stages 4 or 5 of standard Bruce protocol; n = 13) had higher GPBB concentrations than patients who terminated ESET earlier (stages 1, 2 or 3; n = 33) (p = 0.049). Baseline GPBB concentration was not correlated to any of the patients' demographic, clinical and hemodynamic characteristics. Conclusions: GPBB plasma concentration increases after ESET, and it is not related to inducible myocardial ischemia. However, it seems that GPBB release during ESET might be related to exercise load/duration.

Background: Two-dimensional volumetric exercise stress echocardiography (ESE) provides an integrated view of left ventricular (LV) preload reserve through end-diastolic volume (EDV) and LV contractile reserve (LVCR) through end-systolic volume (ESV) changes. Purpose: To assess the dependence of cardiac reserve upon LVCR, EDV, and heart rate (HR) during ESE. Methods: We prospectively performed semi-supine bicycle or treadmill ESE in 1344 patients (age 59.8 ± 11.4 years; ejection fraction = 63 ± 8%) referred for known or suspected coronary artery disease. All patients had negative ESE by wall motion criteria. EDV and ESV were measured by biplane Simpson rule with 2-dimensional echocardiography. Cardiac index reserve was identified by peak-rest value. LVCR was the stress-rest ratio of force (systolic blood pressure by cuff sphygmomanometer/ESV, abnormal values ≤2.0). Preload reserve was defined by an increase in EDV. Cardiac index was calculated as stroke volume index * HR (by EKG). HR reserve (stress/rest ratio) <1.85 identified chronotropic incompetence. Results: Of the 1344 patients, 448 were in the lowest tertile of cardiac index reserve with stress. Of them, 303 (67.6%) achieved HR reserve <1.85; 252 (56.3%) had an abnormal LVCR and 341 (76.1%) a reduction of preload reserve, with 446 patients (99.6%) showing ≥1 abnormality. At binary logistic regression analysis, reduced preload reserve (odds ratio [OR]: 5.610; 95% confidence intervals [CI]: 4.025 to 7.821), chronotropic incompetence (OR: 3.923, 95% CI: 2.915 to 5.279), and abnormal LVCR (OR: 1.579; 95% CI: 1.105 to 2.259) were independently associated with lowest tertile of cardiac index reserve at peak stress. Conclusions: Heart rate assessment and volumetric echocardiography during ESE identify the heterogeneity of hemodynamic phenotypes of impaired chronotropic, preload or LVCR underlying a reduced cardiac reserve. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.

Objectives Primary percutaneous coronary intervention (P-PCI) is the preferred reperfusion option in ST-elevation myocardial infarction, but its benefits become attenuated as time to its potential delivery becomes prolonged. Based on the STrategic Reperfusion Early After Myocardial Infarction trial, we assessed the impact of increasing time delay on outcomes in patients randomised to a pharmacoinvasive strategy (PI) or P-PCI. Methods Thirty-day clinical outcomes were examined according to PCI-related delay (P-RD). Data from hospitals that enrolled >10 randomised patients were used and P-RD categorised as ≤55 min, >55-97 min and >97 min. Results Composite of death/congestive heart failure/ cardiogenic shock/myocardial infarction in PI and P-PCI arms occurred in 10.6% versus 10.3% (≤55 min, p=0.910); 13.9% versus 17.9% (>55-97 min, p=0.148) and 13.5% versus 16.2% (>97 min, p=0.470), respectively. While there was no worsening of outcomes for PI across the P-RD spectrum, this occurred in the P-PCI arm ( p(trend)=0.038). For P-RD ≤55 min, fewer events tended to occur with P-PCI than PI. Conversely, as P-RD increased to >55 min, PI-assigned patients had better outcomes than P-PCI, suggesting an event-free advantage with PI as P-RD increased (p (interaction)=0.094). Analysing P-RD continuously showed that for every 10-min increment there was an increasing trend towards bene fit among PI-assigned patients ( p(interaction)=0.073). Conclusions As P-RD increased, PI outcomes became superior to P-PCI when P-RD is prolonged and exceeds guideline-mandated times. In such circumstances, a PI strategy may provide an alternative reperfusion option. Adverse time delays for delivery of P-PCI should be considered when evaluating reperfusion strategies.