Intracoronary Bolus Research Articles

Use of coronary physiology to guide revascularization in clinical practice: results of the F(FR)2 registry

BackgroundDespite the recommendation of coronary physiology to guide revascularization in angiographically intermediate stenoses without established correlation to ischemia, its uptake in clinical practice is slow.AimsThis study aimed to analyze the use of coronary physiology in clinical practice.MethodsBased on a multicenter registry (Fractional Flow Reserve Fax Registry, F(FR)2, ClinicalTrials.gov identifier NCT03055910), clinical use, consequences, and complications of coronary physiology were systematically analyzed.ResultsF(FR)2 enrolled 2,000 patients with 3,378 intracoronary pressure measurements. Most measurements (96.8%) were performed in angiographically intermediate stenoses. Out of 3,238 lesions in which coronary physiology was used to guide revascularization, revascularization was deferred in 2,643 (78.2%) cases.Fractional flow reserve (FFR) was the most common pressure index used (87.6%), with hyperemia induced by an intracoronary bolus of adenosine in 2,556 lesions (86.4%) and intravenous adenosine used for 384 measurements (13.0%). The route of adenosine administration did not influence FFR results (change-in-estimate -3.1% for regression model predicting FFR from diameter stenosis). Agreement with the subsequent revascularization decision was 93.4% for intravenous and 95.0% for intracoronary adenosine (p = 0.261).Coronary artery occlusion caused by the pressure wire was reported in two cases (0.1%) and dissection in three cases (0.2%), which was fatal once (0.1%).ConclusionsIn clinical practice, intracoronary pressure measurements are mostly used to guide revascularization decisions in angiographically intermediate stenoses. Intracoronary and intravenous administration of adenosine seem equally suited. While the rate of serious complications of wire-based intracoronary pressure measurements in clinical practice seems to be low, it is not negligible.Graphical abstract

Comprehensive invasive evaluation of coronary microcirculation in patients with Takotsubo syndrome

Background and aimsThe etiology and pathophysiology of Takotsubo syndrome (TTS) remain a matter of debate. In murine models of coronary microvascular dysfunction (CMD), abnormalities in myocardial perfusion led to the development of TTS. Importantly, TTS was reversible when normal perfusion was restored. However, in clinical practice, the assessment of coronary microcirculation in patients with TTS has primarily relied on non-invasive or indirect, angiography-derived methods. Methods and ResultsFor the first time, we performed invasive microcirculatory assessment, by both validated techniques currently available in the catheterization laboratory, namely intracoronary bolus and continuous thermodilution, in patients with TTS, upon hospital admission and at short term follow-up. Our findings demonstrate that CMD was consistently present in all patients upon hospital admission, as assessed by both techniques. At a median follow-up of 3 months, after the recovery of left ventricular ejection fraction, two third of patients no longer exhibited CMD. ConclusionsThese findings support the hypothesis that an acute and transient worsening in coronary microvascular function plays a pivotal role in the pathophysiology of TTS.

Comparison of myocardial reperfusion between intracoronary versus intravenous cangrelor administration in patients undergoing primary percutaneous coronary intervention.

Myocardial reperfusion is the main target of treatment in patients with ST-segment elevation myocardial infarction (STEMI). The intracoronary administration of cangrelor bolus could favor a higher local drug concentration, favoring an earlier thrombotic resolution and a reduced distal micro-embolization. Seventy-one patients undergoing primary percutaneous coronary intervention (PCI) for STEMI: 37 treated with intracoronary and 34 with intravenous bolus administration of cangrelor. The primary endpoint was ST-segment elevation resolution (STR) ≥ 50% after 30 min from the end of the PCI. Other explorative reperfusion indices investigated were: STR ≥ 50% at 24 hours, STR ≥ 70% at 30 min, Thrombolysis In Myocardial Infarction frame count and the QT dispersion. Moreover, acute and subacute stent thrombosis, bleeding events and 30-day mortality have been evaluated. More frequent STR ≥ 50% was observed in the intravenous cangrelor bolus group as compared to the intracoronary administration at 30 min (71.9% vs. 45.5%; p = 0.033), the difference was maintained 24 hours after PCI (87.1% vs. 63.6%; p = 0.030). STR ≥ 70% at 30 min was statistically more frequent in the intravenous bolus administration cohort (66.7% vs. 28.6% p = 0.02). At multivariable analysis, intravenous cangrelor administration was significantly related to STR ≥ 50% (odds ratio: 3.586; 95% confidence interval: 1.134-11.335; p = 0.030). The incidence of Bleeding Academic Research Consortium 3-5 bleedings was 15.5% and mortality was 4.2% without any significant difference between the two groups. In conclusion the results of the study do not show any advantages in the administration of intracoronary bolus of cangrelor in patients affected by STEMI and treated with primary PCI.

P135 A CASE OF RIGHT CORONARY ARTERY ANEURYSM COMPLICATED BY ENDOVASCULAR THROMBOSIS

Abstract Coronary artery aneurysm is a rare disorder with prevalence in male population. The most commonly involved vessel is the right coronary artery followed by the anterior descending artery. The most frequent etiologies are coronary atherosclerosis and Kawasaki disease. The treatment of coronary aneurysms with significant stenosis is often surgical, with implantation of covered stents in case of saccular aneurysms. In coronary artery aneurysms without significant stenosis, medical therapy is often the most suitable choice. Case report We present a case of a 68–year–old man with history of hypertension and dyslipidemia, who arrived to our ED with inferior STEMI. Left coronary angiography showed a 75% stenosis of the distal anterior descending artery and subocclusion of the first left marginal artery. Right coronary angiography revealed a severely ectatic vessel (7–8 mm diameter) with intraluminal thrombosis and markedly slowed flow (TIMI 1). Considering the regression of symptoms and ECG alterations, intracoronary bolus of Tirofiban was performed followed by i.v. infusion of 24 hours in association with DAPT. Blood tests did not detect any relevant alterations of coagulation profile but only an heterozygous mutation for MTHFR with slightly altered homocysteine values. Six days later, a second coronary angiography was performed which confirmed the persistence of thrombotic formation into the right coronary artery that was treated with rheolytic thromboaspiration and TIMI 2 final flow. In consideration of the angiographic findings, it was decided not to implant coronary stents. After multidisciplinary team discussion it was decided to associate DAPT with oral anticoagulant therapy (Warfarin 5 mg, INR 2–3) The patient was discharged with indication to continue the triple antithrombotic therapy for 6 months followed by double antithrombotic therapy with ASA and Warfarin. Conclusions Coronary aneurysms in the context of ACS are rare findings, often caused by endovascular thrombosis. Thrombolytic therapy, rheolytic thromboaspiration and anticoagulation therapy are valid tools for the successful treatment of such cases.

Clinical Outcome of Revascularization Deferral With Instantaneous Wave-Free Ratio and Fractional Flow Reserve: A 5-Year Follow-Up Substudy From the iFR-SWEDEHEART Trial.

Background Although physiology-based assessment of coronary artery stenosis using instantaneous wave-free ratio (iFR) and fractional flow reserve (FFR) are established methods of guiding coronary revascularization, its clinical outcome in long-term deferral needs further evaluation, especially with acute coronary syndrome as a clinical presentation. The aim was to evaluate the long-term clinical outcome of deferral of revascularization based on iFR or FFR. Methods and Results This is a substudy of the iFR-SWEDEHEART (Instantaneous Wave-Free Ratio Versus Fractional Flow Reserve in Patients With Stable Angina Pectoris or Acute Coronary Syndrome) randomized clinical trial, where patients deferred from revascularization from each study arm were selected. Nine hundred eight patients deferred from coronary revascularization with iFR (n=473) and FFR (n=435) were followed for 5 years. The national quality registry, SWEDEHEART (Swedish Web-System for Enhancement and Development of Evidence-Based Care in Heart Disease Evaluated According to Recommended Therapies), was used for patient data collection and clinical follow-up. The end point was major adverse cardiac events and their individual components all-cause death, cardiovascular death, noncardiovascular death, nonfatal myocardial infarction, and unplanned revascularization. No significant difference was found in major adverse cardiac events (iFR 18.6% versus FFR 16.8%; adjusted hazard ratio, 1.08 [95% CI, 0.79-1.48]; P=0.63) or their individual components. Conclusions No differences in clinical outcomes after 5-year follow-up were noted when comparing iFR versus FFR as methods for deferral of coronary revascularization in patients presenting with stable angina pectoris and acute coronary syndrome. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT02166736.

Long-term changes in coronary physiology after aortic valve replacement.

The detrimental effects of long-standing severe aortic stenosis (AS) often include left ventricular hypertrophy (LVH) and exhaustion of coronary flow reserve (CFR), the reversibility of which is unclear after valve replacement. Our aims were to 1) investigate whether CFR in the left anterior descending artery (LAD) would improve following valve replacement, and if the change was related to changes in hyperaemic coronary flow (QLAD) and minimal microvascular resistance (Rμ,LAD); and 2) investigate the relationship between changes in CFR and changes in left ventricular mass (LVM) and stroke work (LVSW). We measured intracoronary bolus thermodilution-derived CFR, and continuous thermodilution-derived QLAD and Rμ,LAD before and 6 months after aortic valve replacement. Cardiac magnetic resonance imaging was used to quantify left ventricular anatomy and function for the calculation of LVM and LVSW. Results: Thirty-four patients were included (17 patients had transcatheter aortic valve implantation; 14 had surgical valve replacement with a bioprosthesis and 3 with a mechanical prosthesis) who underwent invasive assessment in the LAD. CFR increased from 2.5 (interquartile range [IQR] 1.5-3.3) at baseline to 3.1 (IQR 2.2-5.1) at follow-up (p=0.005), despite no significant change in QLAD (230±106 mL/min to 250±101 mL/min; p=0.26) or Rμ,LAD (347 [IQR 247-463] to 287 [IQR 230-456]; p=0.20). When indexed for LVM, QLAD was 39% (IQR 8-98%) higher at follow-up compared with baseline (p<0.001). The improvement in CFR was correlated with ΔLVSW, r= -0.39; p=0.047. Conclusions: CFR in the LAD increased significantly at follow-up although global hyperaemic flow and minimal microvascular resistance remained unchanged. Thus, a decrease in resting flow was the cause of CFR improvement. CFR improvement was associated with reduction in LVSW.

Acute coronary syndrome in a young patient with ECG presentation of acute inferior myocardial infarction and acute thrombosis of left main stem coronary artery

Introduction. The left main stem (MS) coronary artery (CA) (MSCA) thrombosis is a rare but potentially lethal manifestation of acute coronary syndrome. The standard approach in treating such patients is the primary percutaneous coronary intervention (pPCI) or CA bypass graft surgery. In some cases, depending on the morphological appearance of the thrombus, findings and flow rates assessed on coronary angiography (CAn), clinical conditions, and cardiologist?s experiences, another possible method of treatment can be the conservative approach using antithrombotic therapy. Case report. A 37-year-old male was admitted to the emergency room with symptoms of an acute myocardial infarction with an ST elevation in diaphragmal localization. Using an emergency CAn, we have visualized a thrombus at the ostial and proximal part of the left MSCA, with no complete obstruction of the blood flow. Initially, dual antithrombotic therapy (ticagrelor and acetylsalicylic acid) was applied, and in the further procedure, it was decided to introduce glycoprotein IIb/IIIa platelet receptor inhibitor (tirofiban) as an intracoronary bolus (0.3 ?g/kg) and later as a continuous infusion (0.1 ?g/kg/min). Four days later, a control CAn and intravascular echocardiography were performed, and it was decided to continue the treatment using conservative therapy without a pPCI procedure. The patient was discharged in good condition with no signs of illness on the eighth day after hospital admission for home recovery, with planned frequent follow-ups in the future. Conclusion. In the case of non-obstructive thrombotic masses without significant atherosclerotic stenotic lesions, conservative treatment modality with the use of aggressive antithrombotic therapy may be considered.

Comparative study of fractional flow reserve and diastolic pressure ratio using a guidewire with a sensor for measuring intravascular pressure

This study aimed to evaluate the correlation and diagnostic agreement between diastolic pressure ratio (dPR) and fractional flow reserve (FFR) in a Japanese real-world setting. Prospective multicenter observational study. This study included 100 patients with intermediate coronary artery stenosis at 4 Japanese hospitals. For these lesions, FFR and dPR were measured using a guidewire with a sensor and a monitor to measure intravascular pressure. The correlation and diagnostic agreement between FFR and dPR were assessed. When both FFR and dPR were negative or positive, the results were considered to be concordant. When one was positive and the other was negative, the result was regarded as discordant (positive discordance, FFR > 0.80 and dPR ≤ 0.89; negative discordance, FFR ≤ 0.80 and dPR > 0.89). Overall, the FFR and dPR were well-correlated (R = 0.841). FFR and dPR were concordant in 89% of cases (concordant normal, 43%; concordant abnormal, 46%) and discordant in 11% (positive discordance, 7%; negative discordance, 4%). No significant difference was observed in the rate of concordant results between patients with and without diabetes mellitus. The diagnostic concordance rate was significantly different among the 3 coronary arteries (right coronary artery, 93.3%; left anterior descending artery, 93.2%; and left circumflex artery, 58.3%; P = .001). Additionally, the rate of concordant results tended to be higher when using intravenous administration of adenosine than when using intracoronary bolus injection of nicorandil (adenosine, 95.1%; nicorandil, 84.7%; P = .103). We found that dPR was highly correlated with FFR, and diagnostic discordance was observed in 11% of the lesions. Several factors, including lesion location and medication for hyperemia, may cause the diagnostic discordance between dPR and FFR.

Factors Predicting 150 and 200 Microgram Adenosine Requirement during Four Increasing Doses of Intracoronary Adenosine Bolus Fractional Flow Reserve Assessment.

Direct intracoronary adenosine bolus is an excellent alternative to intravenous adenosine fractional flow reserve (FFR) measurement. This study, during four increasing adenosine boluses (50, 100, 150, and 200 mcg), aimed to explore clinical and angiographic predictors of coronary stenotic lesions for which the significant ischemic FFR (FFR ≤ 0.8) occurred at 150 and 200 mcg adenosine doses. Data from 1055 coronary lesions that underwent FFR measurement at the Central Chest Institute of Thailand from August 2011 to July 2021 were included. Baseline clinical and angiographic characteristics were analyzed. The FFR ≤ 0.8 occurred at adenosine 150 and 200 mcg boluses in 47 coronary lesions, while the FFR ≤ 0.8 occurred at adenosine 50 and 100 mcg boluses in 186 coronary lesions. After univariable and multivariable logistic regression analyses, four characteristics, including male sex, younger age, non-smoking status, and FFR procedure of RCA, were predictors of the occurrence of FFR ≤ 0.8 at adenosine 150 and 200 mcg doses. Combining all four predictors as a predictive model resulted in an AuROC of 0.72 (95% CI: 0.68–0.76), an 86% negative predictive value. Comparing these four predictors, the FFR procedure of RCA gave the most predictive power, with the AuROC of 0.60 (95% CI: 0.56–0.63).

Factors Associated With Discrepancy of FFR-Based Lesion Classification Between Intracoronary Bolus and Intravenous Infusion of Adenosine

Factors Associated With Discrepancy of FFR-Based Lesion Classification Between Intracoronary Bolus and Intravenous Infusion of Adenosine

Application of tirofiban in patients with acute myocardial infarction complicated with diabetes and undergoing emergency interventional therapy

ABSTRACTObjectives:To investigate the application of tirofiban in patients with acute myocardial infarction complicated with diabetes and undergoing emergency interventional therapy.Methods:Two hundred patients with acute ST-segment elevation myocardial infarction (STEMI) complicated with diabetes who underwent percutaneous coronary intervention (PCI) and found to have high thrombus burden in coronary artery admitted to our hospital from September 2018 to September 2020 were selected as subjects, and were divided into two groups according to the randomization method: the intravenous tirofiban bolus group and the intracoronary tirofiban bolus group, with 100 cases in each group. The levels of LVEF, LVESD and LVEDD were detected immediately after admission and 15 days after therapy, and the enzyme-linked immunosorbent assay was utilized to detect the levels of CK-MB, MMP-9 and hs-CRP. Furthermore, the levels of BNP, TNI, CR and UREA of the patients were analyzed, and the levels of ESR and FIB were detected with an automatic blood rheology analyzer to analyze the TIMI classification and the incidence of MACE in the two groups.Results:Significant differences were seen between the two groups in the levels of various indicators after therapy. Fifteen days after therapy, the levels of LVEF and LVEDD were higher and the level of LVESD was lower in the intracoronary tirofiban bolus group than in the intravenous tirofiban bolus group (p<0.05); 3d after therapy, the levels of CK-MB, MMP-9 and BNP in the intracoronary tirofiban bolus group were lower than those in the intravenous tirofiban bolus group (p<0.05); 3d after therapy, the levels of TNI (p<0.05), CR and UREA in the intracoronary tirofiban bolus group were lower than those in the intravenous tirofiban bolus group, with no statistical difference (p>0.05); Similarly, 3d after therapy, the levels of TNI, Cr and Urea, as well as ESR, FIB and hs-CRP were lower in the intracoronary tirofiban bolus group than in the intravenous tirofiban bolus group (p<0.05). Compared with the intravenous tirofiban bolus group, the intracoronary tirofiban bolus group had a lower number of patients with Grade-0 and Grade-1, but a higher number of patients with Grade-2 and Grade-3 (p<0.05); Moreover, the incidence of MACE in the intracoronary tirofiban bolus group was lower than that in the intravenous tirofiban bolus group (p<0.05).Conclusion:In patients with STEMI complicated with diabetes who underwent PCI and found to have high thrombus burden in coronary artery, intracoronary bolus of tirofiban boasts superior therapeutic efficacy over intravenous bolus of tirofiban in significantly improving cardiac function, reducing myocardial cell damage, and improving renal function and myocardial inflammation of patients.

Evaluation of myocardial reperfusion in patients undergoing cangrelor supported primary PCI for STEMI

Abstract Background Optimal myocardial reperfusion is the main goal of pharmaco-invasive treatment in STEMI patients. Cangrelor is a new intravenous P2Y12 inhibitor, mainly used in intra-procedural PCI setting of STEMI patients. Intracoronary cangrelor bolus application results in high local drug concentrations and may be more effective than a standard intravenous bolus. Aim This study aims to investigate the potential benefits of intracoronary versus intravenous cangrelor bolus in STEMI patients undergoing to primary PCI (p-PCI). Materials and methods Overall, 71 consecutive STEMI patients undergoing p-PCI were treated with intracoronary (n=37) or intravenous (n=34) bolus cangrelor administration with subsequent 2-hour intravenous infusion. The primary end point was ST-elevation reduction (STR) ≥50% at 30 minutes and at 24 hours after p-PCI. Secondary end points were STR ≥70% at 30 min after p-PC, TIMI frame count, and the QT dispersion (QTd). Moreover, stent thrombosis, bleeding events according to BARC classification, and 30-day mortality have been evaluated as safety explorative end points. Results STEMI patients treated with intravenous Cangrelor bolus had a higher rate of STR ≥50% either at 30 minutes (72% vs. 45%; p=0.033) or at 24 hours after p-PCI (87.1% vs. 63.6%; p=0.030) as compared to patients treated with intracoronary Cangrelor bolus; similarly, STR ≥70% at 30 minutes was more frequent in the intravenous bolus group as compared to intracoronary one (67% vs. 29% p=0.02). Furthermore, multivariable analysis demonstrated that intravenous Cangrelor bolus administration was an independent predictor of STR ≥50% (OR 3.586; 95% CI 1.134 to 11.335; p=0.030). No differences according to the TIMI frame count and the QTd were found. No stent thrombosis were observed at 30 days. The incidence of mortality and bleeding events (BARC 3–5) were comparable among study groups (30 days-death: 2.9% vs 5.4%, p=0.606; BARC 3–5 bleedings: 17.6% vs 13.5% p=0.630). Conclusion Intravenous coronary bolus administration of cangrelor in primary PCI is superior to intracoronary treatment with respect to extent of microvascular obstruction, and perfusion. Funding Acknowledgement Type of funding sources: None.

Comparative efficacy of fibrinolytics and glycoprotein IIb/IIIa inhibitors in preventing coronary no-reflow: a network meta-analysis

Abstract Background Coronary no-reflow is a potentially lethal complication of percutaneous coronary intervention (PCI). The optimal approach to preserve coronary reflow during primary PCI is still controversial. Purpose Therefore, we aimed to compare and rank the adjunctive use of fibrinolytic agents and glycoprotein IIb/IIIa inhibitors by network meta-analysis of randomized controlled trials. Methods Pairwise and network meta-analysis were performed using the random-effects model within a frequentist framework. The primary outcome was coronary TIMI flow grade immediately following the intervention. Results 82 studies with a total of 20666 participants were identified, including 7 multi-arm studies. This enabled 94 pairwise comparisons of 35 different adjunctive anticoagulant regimens, all administered in the context of primary PCI. Overall, risk of bias in these studies was rated moderate, and heterogeneity was low with a global I2 value of 20.8%. The figure shows the ranking of the interventions in relation to no adjunctive treatment (NON) and placebo (PLA). In particular, Tirofiban (TIR) alone or in combination with Adenosin (ADE) Nicorandil (NIC) was effective in preventing coronary no-reflow. The route of its administration, intravenous (IV) vs intracoronary (IC), did not matter much. However, its timing as an early IV injection upstream of primary PCI was not beneficial. Eptifibatide (EPT) given as IC bolus followed by continuous IV infusion had an effect comparable to TIR, as well as, among the fibrinolytics, Pamiteplase (PAM) given IV and Urokinase (URO) given IC. Conclusions This comprehensive comparison of fibrinolytics and glycoprotein IIb/IIIa inhibitors demonstrates that TIR, EPT, PAM, and URO can effectively and equally prevent coronary no-reflow in primary PCI. Funding Acknowledgement Type of funding sources: None.

Intracoronary bolus of glycoprotein IIb/IIIa inhibitor as bridging or adjunctive strategy to oral P2Y12 inhibitor load in the modern setting of ST-elevation myocardial infarction.

In the acute management of ST-elevation myocardial infarction (STEMI), glycoprotein IIb/IIIa inhibitors (GPIs) bolus not followed by intravenous infusion is potentially advantageous given their fast onset and offset of action, but clinical evidence in a contemporary setting is limited. We collected data from consecutive STEMI patients admitted to the cardiac catheterization laboratory of the IRCCS A. Gemelli University Polyclinic Foundation from October 2017 to September 2019. Out of 423 consecutive STEMI patients, 297 met the inclusion and exclusion criteria and were included in the study. Of them, 107/297 (36%) received an intracoronary GPI bolus-only during primary percutaneous coronary intervention (PPCI) not followed by intravenous infusion and 190/297 (64%) received standard antithrombotic therapy. Of the 107 GPI-treated, 22/107 (21%) had P2Y<inf>12</inf> inhibitor pretreatment (adjunctive strategy) and 85/107 (79%) did not (bridging strategy). During hospital staying, there was no difference in the primary safety endpoint of TIMI major+minor bleeding (P=0.283), TIMI major (P=0.267) or TIMI minor (P=0.685) bleeding between groups. No stroke event occurred in the GPI group. Despite patients receiving GPI having a significantly higher intraprocedural ischemic burden, no significant differences were found in the efficacy outcomes between groups. Consistent findings were observed for patients receiving GPIs bolus before (bridging strategy) or after (adjunctive strategy) P2Y<inf>12</inf> inhibitors, compared to those receiving standard therapy. Multivariate logistic regression analyses did not find any independent predictors significantly associated to the primary and secondary composite endpoints. In a contemporary real-world population of STEMI patients undergoing PPCI, the use of intracoronary GPIs bolus-only in selected patients at high ischemic risk is safe and could represent a useful antithrombotic strategy both in those pretreated and in those naïve to P2Y<inf>12</inf> inhibitors.

Impact of aging on the effects of intracoronary adenosine, peak hyperemia and its duration during fractional flow reserve assessment.

Functional assessment of coronary stenoses is crucial for determining the correct therapeutic strategy. Age-related modifications in cardiovascular function could alter the functional significance of an intermediate coronary lesion. Therefore, the aim of the present study was to investigate the impact of age on fractional flow reserve (FFR) measurements in patients with intermediate coronary artery disease. We included patients undergoing coronary angiography at our Division of Cardiology from June 2008 to February 2019 for elective indication or recent acute coronary syndrome and receiving FFR assessment for an intermediate coronary stenosis (angiographic 40-70% stenoses). FFR measurement was performed by pressure-recording guidewire (Prime Wire; Volcano Imaging System Philips Healthcare, San Diego, California, USA), after induction of hyperemia with intracoronary boluses of adenosine (from 60 to 720 μg, with dose doubling at each step). We included in our study 276 patients, undergoing FFR evaluation on 314 lesions, that were divided according to age (< or ≥70 years). Elderly patients displayed a higher cardiovascular risk profile and received more often specific therapy. We found significantly higher FFR values and lower Delta FFR and time to recovery in patients with age ≥70 years old even with high-dose adenosine. Elderly patients showed a trend in lower percentage of positive FFRs, especially with high-dose (P = 0.09). Overall, any FFR ≤ 0.80 was observed in 33.5% of younger patients and 21.1% of patients ≥70 years (P = 0.02). Results were confirmed after correction for baseline differences [adjusted odds ratio (95% confidence interval) = 0.60 (0.33-1.09), P = 0.08]. This is one of the first studies investigating the impact of age on the measurement of FFR with high-dose adenosine. Patients with age >70 years old with intermediate CAD are more likely to have higher FFR values and lower duration of hyperemia after adenosine boluses, as compared with younger patients.

Efficacy and safety of single high-dose versus double high-dose intracoronary bolus tirofiban in patients with ST-segment elevation myocardial infarction

Objectives: We evaluated the efficacy and safety of single high-dose versus double high-dose intracoronary bolus tirofiban in patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI). Methods: A total of 80 patients, who were admitted to our clinic and underwent primary PCI, were included in this observational cohort study. The patients were divided into the single high-dose group (n = 40) and the double high-dose group (n = 40) according to the intracoronary bolus tirofiban regime. The primary endpoint was assumed as the incidence of major adverse cardiac event (s) (MACE) defined as all-cause mortality and repeat coronary revascularization (target vessel revascularization [TVR]) at 30 days. MACE and bleeding events were evaluated at 7 and 30 days. Results: The primary endpoint was not significantly different between the single and the double high-dose groups (40.0% vs. 17.5%, p = 0.994). However, a significantly lower 30-day TVR rate was observed in the double high-dose group (27.5% vs. 7.5%, p = 0.019). No significant difference was observed in terms of 30-day all-cause mortality between the two groups (12.5% vs. 10.0%, p = 0.712). Major bleeding events were not observed in any group. Multivariate logistic regression analysis demonstrated that CRUSADE score (Hazard ratio [HR]: 5.721; 95% CI: 2.036 to 16.073, p = 0.001) and platelet count (HR: 1.009; 95% CI: 1.000 to 1.018, p = 0.048) were the independent predictors of bleeding at 7 days. Conclusions: Double high-dose intracoronary bolus tirofiban in STEMI patients undergoing primary PCI was associated with significantly lower 30-day TVR rates without an increase in bleeding events. However, it did not significantly affect MACE and all-cause mortality rates.

Comparison between intracoronary versus intravenous bolus injection of tirofiban on infarct size during primary PCI in patients with acute anterior ST segment elevation myocardial infarction

Abstract Background The latest guidelines considered glycoprotein IIb/IIIa inhibitors (GPI) as a bailout strategy in selected situations in patients presented with acute ST segment elevation myocardial infarction (STEMI) however, did not recommend route of administration over another and did not correlate it to infarct size. Infarct size correlates generally with prognosis following acute myocardial infarction and Reduction in infarct size can boost clinical outcomes and decrease rate of heart failure hospitalization. Purpose To evaluate intracoronary vs intravenous use of tirofiban on reduction of infarct size in STEMI treated with primary PCI. Methods Between February, 2018, and October, 2019, one hundred patients presented within 6 hours of anterior STEMI undergoing primary PCI after exclusion of (rescue PCI, TIMI flow less than II post PCI, Previous MI, Stent thrombosis, Previous CABG, Significant left main occlusion, Pulmonary edema and Cardiogenic shock). Group (A): 50 patients who were treated by intracoronary bolus infusion of tirofiban followed by IV maintenance dose infusion of tirofiban. Group (B): 50 patients who were treated by intravenous bolus infusion of tirofiban followed by IV maintenance dose infusion of tirofiban. Primary endpoint: Infarct size was assessed 1 month after randomization by SPECT. Secondary endpoint: Major adverse cardiovascular events (MACE) during hospital stay (cardiac death, MI, stroke or target vessel revascularization), heart failure and bleeding. Results Patients randomized to intracoronary tirofiban compared with intravenous tirofiban had a significant decrease in the primary end point of infarct size (mean [SD], 14.46% [7.79%] vs 18.06% [7.83%]; P=0.02). Also associated with lower incidence of heart failure (number [%], 8 [16%] vs 17 [34%]; P=0.037). There were no significant differences in any of the MACE or bleeding between the randomized groups at 30 days. Conclusions In patients with anterior STEMI presenting early after symptom onset, intracoronary tirofiban administration when compared to intravenous route during primary PCI resulted in infarction size reduction and lower heart failure incidence mainly driven by enhanced left ventricular systolic function however no distinction between two strategies on MACE or bleeding risk. Results Funding Acknowledgement Type of funding source: None

Intracoronary Versus Intravenous Administration of Eptifibatide During Percutaneous Coronary Intervention in Patients With Acute Coronary Syndromes

Platelet activation and aggregation play a major role in thrombosis formation of coronary arteries in patients with Acute Coronary Syndrome (ACS) and is responsible for most ischemic complications during PCI. There is little information on the benefits and side effects of intracoronary and intravenous injection of Eptifibatide, a potent antiplatelet agent; therefore, this study was performed with the aim to compare coronary blood flow velocity by measurement of TIMI frame count. In intravenous versus intracoronary bolus administration of Eptifibatide during PCI in ACS patients. This non-randomized clinical trial study was performed on 103 patients with acute coronary syndromes who referred to the cardiac emergency ward of Ghaem hospital, Mashhad University of Medical Sciences, and were candidates for urgent coronary angiography and PCI. Forty-eight cases received intracoronary bolus Eptifibatide and 55 intravenous Eptifibatide. TIMI Frame Count and Corrected TIMI Frame Count were used to comparing the effect of these two methods on coronary blood flow velocity. Data were analyzed by SPSS software (version 22). To compare the quantitative variables in the two groups, according to the distribution of variables, the t-test was used if it was normal or the Mann-Whitney test was used if it was not normal. A Chi-square test was also used to compare qualitative variables into two groups. P&lt;0.05 was considered statistically significant. Mean of age, gender, and cardiovascular risk factors were similar in the two groups. There was no significant difference in terms of serum Creatine Kinase MB (CKMB) level, Left Ventricular Ejection Fraction (LVEF), coronary artery lesion length, coronary artery diameter, coronary thrombosis, and coronary artery thrombectomy in two groups. Based on Student's t-test, there was no significant difference between mean TIMI Frame Count in different coronary arteries in the intracoronary and intravenous injection groups (In LAD, P=0.518; For LCX, P=0.576; and in RCA, P=0.964). The complications were observed in 11 patients (22.9%) of the intracoronary injection group and 9 (16.4%) of the intravenous injection group; the difference was not significant (P=0.402). The effects and complications of Eptifibatide were not significantly different in Intracoronary and intravenous administration in ACS patients during PCI and at the time of patients' hospitalization.

Diagnostic utility and safety of intracoronary nicorandil as a hyperemic agent for the measurement of fractional flow reserve

We investigated the diagnostic utility and safety of intracoronary bolus administration of nicorandil compared with intravenous administration of adenosine for evaluating FFR in patients with intermediate (40–70%) coronary stenosis. The FFR values obtained with nicorandil and adenosine showed linear relationship. This correlation is statistically significant with regression coefficient of 0.932 (R2 = 0.834, p < 0.001). The side effects such as bronchospasm, hypotension, and bradycardia were significantly higher after administration of adenosine compared to nicorandil (20% vs. 1.66%, p = 0.001). Intracoronary use of nicorandil seems to be promising in offering the advantages of lesser side effects, similar efficacy, and lesser cost as compared to adenosine.

High dose escalation of intracoronary adenosine in the assessment of fractional flow reserve: A retrospective cohort study.

Maximal hyperaemia for fractional flow reserve (FFR) may not be achieved with the current recommended doses of intracoronary adenosine. Higher doses (up to 720 μg) have been reported to optimize hyperaemic stimuli in small dose-response studies. Real-world data from a large cohort of patients is needed to evaluate FFR results and the safety of high-dose escalation. This is a retrospective study aimed to evaluate the safety and frequency of FFR ≤0.8 after high-dose escalation of intracoronary adenosine. Data were extracted from the medical databases of two university hospitals. Increasing doses (100, 200, 400, 600, and 800 μg) of adenosine were administered as intracoronary boluses until FFR ≤0.8 was achieved or heart block developed. The percentage of FFR ≤0.8 after higher-dose escalation was compared with those at conventional doses, and the predictors for FFR ≤0.8 after higher doses were analysed. In the 1163 vessels of 878 patients, 402 vessels (34.6%) achieved FFR ≤0.8 at conventional doses and 623 vessels (53.6%) received high-dose escalation. An additional 84 vessels (13.5%) achieved FFR ≤0.8 after high-dose escalation. No major complications developed during high-dose escalation. Borderline FFR (0.81–0.85) at the conventional dose, stenosis >60%, and triple-vessel disease increased the likelihood of FFR ≤0.8 after high-dose escalation, but chronic kidney disease decreased it. For vessels of borderline FFR at conventional doses, 46% achieved FFR ≤0.8 after high-dose escalation. In conclusion, High-dose escalation of intracoronary adenosine increases the frequency of FFR ≤0.8 without major complications. It could be especially feasible for borderline FFR values near the 0.8 diagnostic threshold.