What is the optimum adjunctive reperfusion strategy for primary percutaneous coronary intervention?

Role of Brain-Derived Neurotrophic Factor in Anxiety or Depression After Percutaneous Coronary Intervention

Anxiety or depression after percutaneous coronary intervention (PCI) is one of the key clinical problems in cardiology that need to be solved urgently. Brain-derived neurotrophic factor (BDNF) may be a potential biomarker for the pathogenesis and treatment of anxiety or depression after PCI. This article reviews the correlation between BDNF and cardiovascular system and nervous system from the aspects of synthesis, release and action site of BDNF, and focuses on the latest research progress of the mechanism of BDNF in anxiety or depression after PCI. It includes the specific mechanisms by which BDNF regulates the levels of inflammatory factors, reduces oxidative stress damage, and mediates multiple signaling pathways. In addition, this review summarizes the therapeutic potential of BDNF as a potential biomarker for anxiety or depression after PCI.

Segmental and transmural motion of the rat myocardium estimated using quantitative ultrasound with new strategies for infarct detection

Introduction: The estimation of myocardial motion abnormalities has great potential for the early diagnosis of myocardial infarction (MI). This study aims to quantitatively analyze the segmental and transmural myocardial motion in MI rats by incorporating two novel strategies of algorithm parameter optimization and transmural motion index (TMI) calculation. Methods: Twenty-one rats were randomly divided into three groups (n = 7 per group): sham, MI, and ischemia-reperfusion (IR) groups. Ultrasound radio-frequency (RF) signals were acquired from each rat heart at 1 day and 28 days after animal model establishment; thus, a total of six datasets were represented as Sham1, Sham28, MI1, MI28, IR1, and IR28. The systolic cumulative displacement was calculated using our previously proposed vectorized normalized cross-correlation (VNCC) method. A semiautomatic regional and layer-specific myocardium segmentation framework was proposed for transmural and segmental myocardial motion estimation. Two novel strategies were proposed: the displacement-compensated cross-correlation coefficient (DCCCC) for algorithm parameter optimization and the transmural motion index (TMI) for quantitative estimation of the cross-wall transmural motion gradient. Results: The results showed that an overlap value of 80% used in VNCC guaranteed a more accurate displacement calculation. Compared to the Sham1 group, the systolic myocardial motion reductions were significantly detected (p < 0.05) in the middle anteroseptal (M-ANT-SEP), basal anteroseptal (B-ANT-SEP), apical lateral (A-LAT), middle inferolateral (M-INF-LAT), and basal inferolateral (B-INF-LAT) walls as well as a significant TMI drop (p < 0.05) in the M-ANT-SEP wall in the MI1 rats; significant motion reductions (p < 0.05) were also detected in the B-ANT-SEP and A-LAT walls in the IR1 group. The motion improvements (p < 0.05) were detected in the M-INF-LAT wall in the MI28 group and the apical septal (A-SEP) wall in the IR28 group compared to the MI1 and IR1 groups, respectively. Discussion: Our results show that the MI-induced reductions and reperfusion-induced recovery in systolic myocardial contractility could be successfully evaluated using our method, and most post-MI myocardial segments could recover systolic function to various extents in the remodeling phase. In conclusion, the ultrasound-based quantitative estimation framework for estimating segmental and transmural motion of the myocardium proposed in our study has great potential for non-invasive, novel, and early MI detection.

Comprehensive Assessment of the Left Ventricular Systolic Function in the Elderly with Acute Myocardial Infarction Using Echocardiography

Aim

To evaluate the left ventricular (LV) systolic function in elderly with non-ST elevation myocardial infarction (NSTEMI) and ST elevation myocardial infarction (STEMI) using real-time three-dimensional echocardiography (RT-3DE) and two-dimensional speckle tracking imaging (STI).

Methods

Forty NSTEMI and forty STEMI patients after undergoing percutaneous coronary artery intervention (PCI) were enrolled. The myocardial segments were supplied by the infarct-related artery (Myo-_IRA) which were indicated by the selective coronary arteriography (SCA). The LV end-diastolic volume (LVEDV), end-systolic volume (LVESV), stroke volume (LVSV) and ejection fraction (LVEF) were acquired by 4D LV Volume Tom Tec. LV longitudinal peak systolic strain (LPSS), radial peak systolic strain (RPSS), circumferential peak systolic strain (CPSS) of Myo-_IRA segments, LV rotational peak degree in the base (rot-_base) and in the apex (rot-_apex), and twist were acquired by strain analysis software. Forty older healthy individuals were included as normal controls.

Results

The LVEF of the NSTEMI and STEMI patients at 1 week after PCI were significantly lower (P<0.05), then, this parameter was improved in both groups after 3 months, but was still significantly lower than that of the controls (P<0.05). The LPSS, RPSS, CPSS of the Myo_−IRA segments, rot_−Base, rot_−Apex and twist in both groups were significantly lower than those in the controls. The LPSS and CPSS of the Myo-IRA segments, rot_−Base, rot_−Apex and twist in NSTEMI patients were obviously higher than those in STEMI patients in 1 week and 3 months after PCI (P<0.05). After 3 months, the RPSS of NSTEMI patients was improved notably and was obviously higher than that of STEMI patients (P<0.05). All these values in STEMI and NSTEMI patients were improved after 3 months, apart from LPSS in STEMI patients (P>0.05), but were still significantly lower than those in the controls (P<0.05).

Conclusion

RT-3DE and STI can sensitively assess LV systolic function with different extents of transmural damage.

De-escalation of anti-platelet therapy in patients with acute coronary syndromes undergoing percutaneous coronary intervention: a narrative review

Objective:

Dual antiplatelet therapy (DAPT) with aspirin and a P2Y₁₂ receptor inhibitor is the cornerstone of treatment in patients with acute coronary syndromes (ACS) and in those undergoing percutaneous coronary intervention (PCI). In current clinical situation, availability of different oral P2Y₁₂ inhibitors (clopidogrel, prasugrel, and ticagrelor) has enabled physicians to switch among therapies owing to specific clinical scenarios. Although optimum time, loading dose and interval of transition between P2Y₁₂ inhibitors is still controversial and needs further evidence, switching between oral inhibitors frequently occurs in clinical practice for several reasons.

Data sources:

This review was based on data in articles published in PubMed up to June 2018, with the following keywords “antiplatelet therapy”, “ACS”, “PCI”, “ticagrelor”, and “clopidogrel”.

Study selection:

Original articles and critical reviews on de-escalation strategy in ACS patients after PCI were selected. References of the retrieved articles were also screened to search for potentially relevant papers.

Results:

Safety concerns associated with switching between antiplatelet agents, has prompted the use of clopidogrel for patients with ACS especially after PCI as a de-escalation strategy. Practical considerations for de-escalating therapies in patients with ACS such as reducing dose of P2Y₁₂ inhibitors or shortening duration of DAPT (followed by aspirin or P2Y₁₂ receptor inhibitor monotherapy) as potential options are yet to be standardized and validated.

Conclusions:

Current review will provide an overview of the pharmacology of common P2Y₁₂ inhibitors, definitions of de-escalation and different de-escalating strategies and its outcomes, along with possible direction to be explored in de-escalation.

Hypoxia and Ischemia Promote a Maladaptive Platelet Phenotype

Supplemental Digital Content is available in the text.

Objective—

Reduced blood flow and tissue oxygen tension conditions result from thrombotic and vascular diseases such as myocardial infarction, stroke, and peripheral vascular disease. It is largely assumed that while platelet activation is increased by an acute vascular event, chronic vascular inflammation, and ischemia, the platelet activation pathways and responses are not themselves changed by the disease process. We, therefore, sought to determine whether the platelet phenotype is altered by hypoxic and ischemic conditions.

Approach and Results—

In a cohort of patients with metabolic and peripheral artery disease, platelet activity was enhanced, and inhibition with oral antiplatelet agents was impaired compared with platelets from control subjects, suggesting a difference in platelet phenotype caused by the disease. Isolated murine and human platelets exposed to reduced oxygen (hypoxia chamber, 5% O₂) had increased expression of some proteins that augment platelet activation compared with platelets in normoxic conditions (21% O₂). Using a murine model of critical limb ischemia, platelet activity was increased even 2 weeks postsurgery compared with sham surgery mice. This effect was partly inhibited in platelet-specific ERK5 (extracellular regulated protein kinase 5) knockout mice.

Conclusions—

These findings suggest that ischemic disease changes the platelet phenotype and alters platelet agonist responses because of changes in the expression of signal transduction pathway proteins. Platelet phenotype and function should, therefore, be better characterized in ischemic and hypoxic diseases to understand the benefits and limitations of antiplatelet therapy.

Antithrombotic Approaches in Acute Coronary Syndromes: Optimizing Benefit vs Bleeding Risks

It is estimated that in the United States, each year, approximately 620,000 persons will experience an acute coronary syndrome and approximately 70% of these will have non-ST-elevation acute coronary syndrome. Cardiovascular disease still accounts for 1 of every 3 deaths in the United States, and there is an urgent need to improve the prognosis of patients presenting with acute coronary syndrome. Cardiovascular mortality and ischemic complications are common after acute coronary syndrome, and the advent of newer antithrombotic therapies has reduced ischemic complications, but at the expense of greater bleeding. The new antithrombotic agents also raise the challenge of choosing between multiple potential therapeutic combinations to minimize recurrent ischemia without a concomitant increase in bleeding, a decision that often varies according to an individual patient's relative propensity for ischemia versus hemorrhage. In this review, we will synthesize the available information to arm health care providers with the contemporary knowledge on antithrombotic therapy and individualize treatment decisions.

The immediate protective response to microbial challenge

The innate immune system detects infection and tissue injury through different families of pattern-recognition receptors (PRRs), such as Toll-like receptors. Most PRR-mediated responses initiate elaborate processes of signaling, transcription, translation, and secretion of effector mediators, which together require time to achieve. Therefore, PRR-mediated processes are not active in the early phases of infection. These considerations raise the question of how the host limits microbial replication and invasion during this critical period. Here, we examine the crucial defense mechanisms, such as antimicrobial peptides or extracellular traps, typically activated within minutes of the initial infection phase, which we term the "immediate protective response". Deficiencies in different components of the immediate protective response are often associated with severe and recurrent infectious diseases in humans, highlighting their physiologic importance.

Risk stratification for ST segment elevation myocardial infarction in the era of primary percutaneous coronary intervention

Acute coronary syndromes presenting with ST elevation are usually treated with emergency reperfusion/revascularisation therapy. In contrast current evidence and national guidelines recommend risk stratification for non ST segment elevation myocardial infarction (NSTEMI) with the decision on revascularisation dependent on perceived clinical risk. Risk stratification for STEMI has no recommendation. Statistical risk scoring techniques in NSTEMI have been demonstrated to improve outcomes however their uptake has been poor perhaps due to questions over their discrimination and concern for application to individuals who may not have been adequately represented in clinical trials. STEMI is perceived to carry sufficient risk to warrant emergency coronary intervention [by primary percutaneous coronary intervention (PPCI)] even if this results in a delay to reperfusion with immediate thrombolysis. Immediate thrombolysis may be as effective in patients presenting early, or at low risk, but physicians are poor at assessing clinical and procedural risks and currently are not required to consider this. Inadequate data on risk stratification in STEMI inhibits the option of immediate fibrinolysis, which may be cost-effective. Currently the mode of reperfusion for STEMI defaults to emergency angiography and percutaneous coronary intervention ignoring alternative strategies. This review article examines the current risk scores and evidence base for risk stratification for STEMI patients. The requirements for an ideal STEMI risk score are discussed.

Statins, percutaneous coronary intervention and myocardial infarction

Peri-procedural myocardial infarction occurs in up to 40% of otherwise successful percutaneous coronary intervention (PCI) procedures and such patients have a worse long term prognosis than those who do not have this complication. Statins administered at the time of PCI, particularly before the procedure, have been shown to reduce the risk of myocardial infarction during PCI, but the applicability of this treatment may be limited because of the widespread use of statins in patients with existing coronary artery disease, or in those at risk of developing the disease. The results of a study are reported in this issue of the journal in which a single dose of atorvastatin is given prior to PCI to patients already taking a statin, and shows a significant reduction in the risk of peri-procedural myocardial infarction. It may be that a single supplemental dose of a statin at PCI to all patients could confer clinical benefit.