Effect of aspirin discontinuation according to individualised patient bleeding and ischemic risks after PCI: a TWILIGHT trial sub-analysis

Background

The TWILIGHT trial demonstrated a reduction in BARC 2, 3 or 5 (BARC-235) bleeding without an increase in ischemic events at 1-year in high-risk PCI patients randomized to placebo or aspirin (ASA) on a background of ticagrelor 3-months after PCI. However, the effect of ASA discontinuation according to baseline risk of bleeding and ischemic events remain unclear.

Purpose

To a) develop separate models to predict the risk of bleeding and ischemic events, and b) to assess treatment effect of ASA discontinuation across the risk strata.

Methods

Using the TWILIGHT patient database (N=7,119), two multivariable models, one for BARC-235 bleeding and one for CV death, nonfatal MI or nonfatal ischemic stroke (ischemic endpoint) were developed, and their predictive capacity was assessed. The effect of randomized treatment on bleeding and ischemic events across different patient risk-group categories as determined by the risk scores was investigated.

Results

At 1-year, 350 (5.4%) patients experienced a BARC-235 bleeding event and 258 (3.6%) experienced an ischemic event. Independent predictors of BARC-235 included haemoglobin levels at index PCI, proton-pump inhibitor non-use at discharge, age, liver disease and active smoking (c-statistic 0.64). Independent predictors of the ischemic outcome included a positive troponin ACS, prior CABG, diabetes, age, peripheral artery disease, prior PCI, a history of congestive heart failure, active smoking, the level of index PCI complexity, and prior MI (c-statistic 0.71). The risk of a BARC-235 almost doubled between patients in lower versus higher bleeding risk categories (4.3% versus 7.9%) and ischemic risk more than tripled between patients in lower versus higher ischemic risk categories (2.0% versus 7.0%) (see Figure 1). There was no evidence of a differential treatment effect for dual antiplatelet therapy versus ticagrelor monotherapy across the different risk categories of bleeding (interaction P=0.54) and ischemic risk (interaction P=0.95) (Table 1).

Conclusion

Individual patient bleeding and ischemic risks after PCI can both be readily characterised with good discrimination. The effect of ASA discontinuation in preventing bleeding in ticagrelor-treated patients was consistent regardless of baseline bleeding risk. There was no evidence for increased ischemic events with ASA discontinuation according to baseline ischemic risk.

Funding Acknowledgement

Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): AstraZenecaIcahn School of Medicine at Mount Sinai

A lack of race and ethnicity data in the treatment of hereditary hemorrhagic telangiectasia: a systematic review of intravenous bevacizumab efficacy

BACKGROUND

For extreme hereditary hemorrhagic telangiectasia (HHT) disease, treatments such as intravenous bevacizumab are often utilized. However, whether its efficacy is similar across diverse races and ethnicities is unclear.

METHODS

In this systematic review, we performed a search for English-language articles identified through PubMed, Embase, and Scopus databases whose research occurred in the United States (US). Search terms related to HHT, epistaxis, and intravenous bevacizumab. We searched specifically for the intervention of intravenous bevacizumab because the term serves as a suitable surrogate to convey a patient who has both a diagnosis of HHT and established care. We focused on number of patients recruited in intravenous bevacizumab trials who were identified by race or ethnicity.

RESULTS

Our search identified 79 studies, of which four were conducted in the US. These four were selected for our systematic review. In these studies, 58 total patients were evaluated (ranging from 5 to 34 participants), whereby, information on age and gender were included. However, none of the US-based studies shared race or ethnicity data.

CONCLUSION

Inability to find studies regarding intravenous bevacizumab use in patients with HHT in which race and ethnicity are reported limits our ability to understand the therapy's efficacy in specific populations. Without emphasis on race and ethnicity in such trials, showing the potential of HHT-related diversity in individuals with this disease may reaffirm implicit bias around HHT diagnosis and treatment. Future work on HHT should emphasize sociodemographic data collection and reporting in an effort to understand this disease in diverse populations.

P2815Antiplatelet therapy with cangrelor in patients undergoing surgery after coronary stent implantation: a real-world bridging protocol experience

Background

Perioperative management of dual antiplatelet therapy (DAPT) after percutaneous coronary intervention (PCI) in patients deemed at high thrombotic risk undergoing non-deferrable surgery remains poorly defined. Cangrelor represents a potential treatment option as a “bridge” from discontinuation of oral P2Y12 receptor antagonists to surgical procedures, but data in this setting are still scant.

Purpose

We sought to describe a real-world experience of a bridging protocol using cangrelor for patients referred to relevant bleeding risk surgery requiring withdrawal of DAPT.

Methods

We collected data from 7 Italian centers on patients with previous PCI, still on DAPT, undergoing non-deferrable surgery which required discontinuation of one or both antiplatelet agents. A standardized bridging protocol using cangrelor infusion before and eventually after surgery was applied (Figure 1).

Results

Between December 2017 and January 2019, a total of 18 patients (mean age 70±10 years; male 85%) were enrolled. In the majority (89%) of patients, the index PCI was performed due to acute coronary syndrome (ACS) and 2±1.7 stents per patient were implanted. All patients required non-deferrable, intermediate-high bleeding risk surgery as pulmonary lobectomy, colectomy, endoscopic bladder surgery, paranasal sinus surgery, coronary artery by-pass surgery and valvular repair, hip replacement, endoscopy sphincterotomy. High thrombotic risk categories included PCI time <1 month, SCA time <3 months, stent failure occurrence, previous Absorb BVS implantation. Due to the surgical bleeding risk, discontinuation of P2Y12 inhibitor was required 5 days before surgery (ticagrelor, n=13; prasugrel=1; clopidogrel, n=5). All patients but 1 maintained aspirin through the perioperative phase. Cangrelor infusion was started at a bridging dose (0.75 mcg/kg/min) 3 days before planned surgery and was discontinued 6.9±1.5 hours before. After surgery, drainages were left in all patients but 3. In 56% of patients, cangrelor was resumed within 24 hours from surgery (mean time 9±7 hours) for a mean of 36±38 hours. Drainages were removed after discontinuation of cangrelor, in order to reduce bleeding complications. Within 2 hours from post-operative cangrelor discontinuation, a 300 mg clopidogrel loading dose was administered. No major ischemic adverse outcomes occurred during hospital stay and up to 30 days follow-up. The mean Hb drop was 2±1.8 g/dl, 7 patients received blood transfusions consistent with the type of surgeries and no life-threatening or fatal bleeding occurred.

Figure 1. Standardized bridging protocol.

Conclusions

Peri-operative bridge therapy with cangrelor is a feasible approach for stented patients at high thrombotic risk referred to non-deferrable surgery requiring DAPT discontinuation. Larger studies are warranted to support the safety of this strategy.

The effect of T-2 toxin on active sodium transport across frog skin in the presence of ADH and amphotericin B

1. The effect of T-2 toxin on active sodium transport across frog skin both in the presence and in the absence of stimulants of sodium transport, such as Amphotericin B and ADH, was studied using the short circuit current technique with the following results. 2. T-2 toxin produces inhibition of active sodium transport in a dose-response correlation. 3. This effect is irreversible since the washing out of the tissue does not restore its functionality. This indicates that the micotoxin may cross the cellular membrane and act on the internal site. 4. ADH partially removes the inhibitory effect of T-2 toxin. 5. The increase of the sodium pool in the cell as determined by Amphotericin B does not reverse the inhibitory effect of T-2 toxin. 6. The biological significance of these data is discussed in regard to the possible effect of T-2 toxin on Na+, K+-ATPase activity either directly or by a reduction in the metabolic supply of substrates, or by a modified stoichiometry of the pump reaction.