Revascularization Strategies in Patients With STEMI: Culprit-Only vs Multivessel Revascularization Using Percutaneous Coronary Intervention

BACKGROUND

Approximately 50% of patients undergoing primary percutaneous coronary intervention (PCI) for ST-elevation myocardial infarction (STEMI) have multivessel coronary disease (MVD). Evidence on the best PCI approach for these patients is conflicting. The aim of this study is to examine Australian data from the CONCORDANCE registry to describe the practice and outcomes of patients receiving multivessel vs culprit-only PCI.

METHODS

Two cohorts were constructed from MVD-STEMI patients undergoing primary PCI at 41 hospitals between 2009 and 2015: culprit-only PCI (n = 587; 87%) and multivessel PCI (n = 82; 12%). Clinical characteristics were described, and the outcomes were all-cause mortality, heart failure, and myocardial reinfarction, in-hospital and at 6-month follow-up. The relative prevalence of each procedure over time was also described.

RESULTS

The patient cohorts were comparable in age, sex, and cardiovascular risk factors. Patients with higher Killip scores were more likely to receive multivessel PCI (P=.02). The multivessel group was significantly more likely to have in-hospital cardiogenic shock (P<.01), myocardial reinfarction (P=.02), cardiac arrest (P=.02), and stroke (P=.01). There was no difference in the incidence of ischemic events at 6 months, but the multivessel group had a lower rate of planned repeat revascularizations (12% vs 2%; P=.03). There was no difference in the relative frequency of multivessel vs culprit-only PCI during the observation period.

CONCLUSIONS

The relative frequency of multivessel vs culprit-only PCI has not changed from 2009-2015. Index complete revascularization for STEMI-MVD patients is more likely to be performed in those with worse presentations and is associated with worse in-hospital complications.

P2717Type-II MI and chronic myocardial injury rates, invasive management and 4 year mortality among consecutive patients undergoing high sensitivity troponin T testing in the emergency department

Background

In emergency departments (EDs), assessment of patients with suspected acute coronary syndromes (ACS) represents a major workload and high sensitivity troponin (HsTn) T and I levels are frequently measured. A minority of patients have final diagnosis of myocardial infarction (MI).

Methods and results

Among 2738 consecutive patients with suspected ACS presenting to ED at Liverpool Hospital, Australia, between March and June 2014, we determined the relative frequencies of 3 patient groups: type-I MI, type-II MI including chronic myocardial injury (CMI), and assessed the use of invasive and pharmacological therapies and 4-year outcomes. Adjudication of MI was according to the 4th universal definition of MI as follows: 1) type-I MI; 2) type-II MI (including acute myocardial injury), and 3) CMI. Of 995 patients (36%) median age 76 years [IQR 65–83]), with at least 2 HsTnT measurements and one >14ng/l, 727 (73%) had chronic myocardial injury, 171 (17%) had type-II MI; and 97 (9.7%) had type-I MI. Patients with type-I MI (mean age 63 years) were younger than those with type-II MI or chronic myocardial injury by 12 and 14 years respectively. The main triggering factors for type-II MI/acute injury included: sepsis (21.1%), acute heart failure (18.3%), tachyarrhythmia (16.9%), anaemia (8.6%) and a combination of factors (16%). In-hospital angiography (62% had PCI) rates were 95% for patients with type-I MI, 24% (7% PCI) for those with type-II MI and 3.4% for CMI. Mortality at 4 years was 55% for type-II MI, 44% for CMI and 18% for type-1 MI (P<0.001; Figure), though after Cox modelling adjusting for age, gender, renal function and COPD, compared to type 1 MI, type-II MI (hazard ratio 1.61 [95% CIs 0.90–2.86]; p=0.106) and CMI (hazard ratio 1.01 [95% CIs 0.59–1.74]; p=0.963) were not independently associated with increased late mortality, largely because patients with type 1 MI were a decade younger.

Conclusion

Among unselected patients undergoing HsTnT testing in EDs, type-II MI including acute myocardial injury was more common than type-I MI. Chronic myocardial injury, which occurred in 3 of 4 patients. While patients with type-II MI acute myocardial injury had higher late mortality rates than type-I MI, though after multivariable analyses mortality rates were not different.

P6443Late outcomes in patients undergoing PCI for ST elevation myocardial infarction with respect to diabetic status and completeness of revascularisation

Objectives

This paper examines the degree to which the poor prognosis of ST elevation myocardial infarction (STEMI) patients with diabetes mellitus (DM) can be attributed to incomplete revascularization (ICR).

Background

Cardiovascular disease is the most common cause of death for patients with DM; patients with DM often have complex coronary disease and ICR. In STEMI the relative impact of DM and ICR is uncertain as these two factors frequently co-exist, the potential for confounding is high.

Methods and results

Of 589 consecutive STEMI patients, 22% had DM, who compared to patients without DM were of similar age (59 years), were more often female, had more hypertension and dyslipidaemia, but less often were smokers. A residual SYNTAX Score (rSS) >8, which defined ICR, occurred in 33%. Late cardiac death [median 3.5 years] was 4% among those without DM and 12% in those with DM (p=0.002) (p<0.001), and was 3% among 396 with rSS≤8 and 12% in 193 patients with rSS>8 (p<0.001). Patients with both ICR and DM accounted for only 8% of the STEMI population but 30% of all cardiac deaths. At final follow up (3.5 years) cardiac death rates (see Figure) were 22% in patients with both DM and ICR; these were significantly higher than rates in patients with ICR but no-DM (9%, p=0.034), and those with DM and rSS≤8 (6%, p<0.019). Multivariable analysis for cardiac death found a HR for ICR of 2.89 (95% CI 1.31–6.37; p=0.009) and a HR for DM of 5.18 (95% CI 2.45–10.97, p<0.001).

Diabetes, cardiac death & rSS

Conclusions

While ICR in DM patients with STEMI predicts a significantly poorer outcome, the poor prognosis seen in patients with DM is not explained by the degree of ICR alone. Both ICR and DM contribute independently to the risk of cardiac death in STEMI patients.

P2708Clopidogrel versus ticagrelor on coronary microvascular and peripheral endothelial function after non-ST elevation acute coronary syndrome: a randomised trial

Background

Ticagrelor has been shown to reduce microvascular injury and improve peripheral endothelial function compared to clopidogrel in ST-elevation myocardial infarction and stable patients. However, comparable data is lacking in non-ST elevation acute coronary syndromes (NSTE-ACS).

Purpose

To investigate the effects of clopidogrel versus ticagrelor on coronary microvascular function and peripheral endothelial function in NSTE-ACS patients.

Methods

Patients hospitalised for NSTE-ACS were prospectively randomised 1:1 to clopidogrel (300mg loading then 75mg daily) or ticagrelor (180mg loading then 90mg twice-daily). Coronary microvascular function was assessed with index of microcirculatory resistance (IMR) in the infarct related artery (IRA) and non-IRA before and after percutaneous coronary intervention (PCI) using a standard pressure-temperature coronary wire. Peripheral endothelial function was assessed with flow-mediated vasodilation (FMD) of the brachial artery, performed on admission prior to antiplatelet loading and again before discharge, using a pneumatic cuff and 10MHz linear ultrasound transducer.

Results

A total of 40 patients were included for analysis (Figure 1). Median age was 53.5 (IQR 49.0–61.5) years, 35 (87.5%) were male, 11 (27.5%) had diabetes, 19 (47.5%) were smokers. Median peak troponin T was 527 (175–1006.5) ng/L, median GRACE score 91.5 (78.3–103.3) and median SYNTAX score 13 (6–20). Baseline characteristics were similar between both groups. There was no significant difference in the median baseline IMR between the 2 groups in both the IRA (clopidogrel 14.4 [IQR 12.2–18.6] vs ticagrelor 20.8 [11.3–27.4], p=0.22) and non-IRA (14.0 [11.0–22.0] vs 14.0 [10.0–29.5] respectively, p=0.74). 28 patients underwent PCI to the IRA (12 clopidogrel, 16 ticagrelor). There was no significant difference in the median post-PCI IMR between the 2 groups (19.5 [14.5–24.5] vs 29.0 [19.0–35.6] respectively, p=0.11). However, there was significant worsening of post-PCI compared with pre-PCI IMR (19.5 vs 15.0, p=0.049) in the clopidogrel group but not in the ticagrelor group (29.0 vs 25.4, p=0.47). FMD was performed in 23 patients (9 clopidogrel, 14 ticagrelor). Admission median %FMD (change in post-stimulus diameter as a percentage of the baseline diameter) was similar between the 2 groups (13.2% [10.1–17.6] vs 12.2% [10.2–15.8] respectively, p=0.41). There was a trend towards higher median pre-discharge %FMD in the ticagrelor group (12.8% [12.2–18.0]) compared to the clopidogrel group (10.4% [9.5–11.2], p=0.09). There was a trend towards lower pre-discharge %FMD compared to admission in the clopidogrel group (10.4% vs 13.2%, p=0.05) but not the ticagrelor group (12.8% vs 12.2%, p=0.43).

Figure 1

Conclusions

In our NSTE-ACS patients undergoing PCI, ticagrelor resulted in less disruption of coronary microvascular function and may also have beneficial effects on peripheral endothelial function compared to clopidogrel.

Acknowledgement/Funding

Dr. James Xu is funded by a post-graduate scholarship from the Australian Government Research Training Program (RTP)

Standard versus ultrasound-guided radial and femoral access in coronary angiography and intervention (SURF): a randomised controlled trial

AIMS

This study aimed to compare outcomes in unselected patients undergoing cardiac catheterisation via transradial versus transfemoral access and standard versus ultrasound-guided arterial access.

METHODS AND RESULTS

This was a prospective, randomised (radial vs. femoral and standard vs. ultrasound), 2x2 factorial trial of 1,388 patients undergoing coronary angiography and percutaneous coronary intervention. The primary outcome was a composite of ACUITY (Acute Catheterization and Urgent Intervention Triage strategY) major bleeding, MACE (death, stroke, myocardial infarction or urgent target lesion revascularisation) and vascular complications at 30 days. Transradial access reduced the primary outcome (RR 0.37, 95% CI: 0.17-0.81; p=0.013), mostly driven by ACUITY major bleeding (RR 0.343, 95% CI: 0.123-0.959; p=0.041) when compared with the transfemoral approach. There was no difference in the primary outcome between standard and ultrasound guidance (p=0.76). Ultrasound guidance, however, reduced mean access time (93 sec vs. 111 sec; p=0.009), attempts (1.47 vs. 1.9; p<0.0001), difficult accesses (4.5% vs. 9.2%; p=0.0007), venepuncture (4.1% vs. 9.2%; p<0.0001) and improved first-pass success (73% vs. 59.7%; p<0.0001).

CONCLUSIONS

Transradial access significantly reduced the composite outcome compared to transfemoral access. Ultrasound guidance did not reduce the primary outcome compared to the standard technique, but significantly improved the efficiency and overall success rate of arterial access.