Periprocedural Myocardial Infarction

Interplay between hypoxia inducible Factor-1 and mitochondria in cardiac diseases

Ischemic heart diseases and cardiomyopathies are characterized by hypoxia, energy starvation and mitochondrial dysfunction. HIF-1 acts as a cellular oxygen sensor, tuning the balance of metabolic and oxidative stress pathways to provide ATP and sustain cell survival. Acting on mitochondria, HIF-1 regulates different processes such as energy substrate utilization, oxidative phosphorylation and mitochondrial dynamics. In turn, mitochondrial homeostasis modifications impact HIF-1 activity. This underlies that HIF-1 and mitochondria are tightly interconnected to maintain cell homeostasis. Despite many evidences linking HIF-1 and mitochondria, the mechanistic insights are far from being understood, particularly in the context of cardiac diseases. Here, we explore the current understanding of how HIF-1, reactive oxygen species and cell metabolism are interconnected, with a specific focus on mitochondrial function and dynamics. We also discuss the divergent roles of HIF in acute and chronic cardiac diseases in order to highlight that HIF-1, mitochondria and oxidative stress interaction deserves to be deeply investigated. While the strategies aiming at stabilizing HIF-1 have provided beneficial effects in acute ischemic injury, some deleterious effects were observed during prolonged HIF-1 activation. Thus, deciphering the link between HIF-1 and mitochondria will help to optimize HIF-1 modulation and provide new therapeutic perspectives for the treatment of cardiovascular pathologies.

Mortality After Procedural or Spontaneous Myocardial Infarction

BACKGROUND

It remains unclear whether procedural myocardial infarction (pMI) and spontaneous myocardial infarction (spMI) have a similar impact on prognosis.

OBJECTIVES

The aim of this study was to assess mortality after pMI and spMI.

METHODS

Patients with chronic coronary syndrome (CCS) and baseline troponin ≤1× the upper reference level (URL) or with acute spMI who underwent percutaneous coronary intervention (PCI) were included. PMI was defined as post-PCI troponin increase >1× URL in patients with CCS. SpMI comprised any acute coronary syndrome with elevated troponin. The 1-year risk of all-cause death was assessed after pMI and spMI across 3 strata of troponin elevation (>1-5×, >5-35×, and >35× URL), with CCS patients having post-PCI troponin ≤1× URL as a reference group. Conventional troponin I was measured using the Architect methodology (Abbott).

RESULTS

Among 10,707 patients undergoing PCI from 2012 to 2020, 8,515 patients presented with CCS and 2,192 with spMI. Among CCS patients, 913 (10.7%) had pMI. Troponin peaks >1-5×, >5-35×, and >35× URL were observed in 53%, 41%, and 6% of patients with pMI, and in 24%, 38%, and 37% of patients with spMI, respectively. Mortality at 1 year was higher after pMI (7.7%; adjusted HR: 4.40; 95% CI: 1.59-12.2), and spMI (8.5%; adjusted HR: 7.57; 95% CI: 5.44-10.5) with troponin peak >35× URL compared with no-MI (1.4%). Mortality was also increased after spMI with troponin peak >1-5× or >5-35× URL.

CONCLUSIONS

Mortality at 1 year was significantly increased after pMI and spMI with troponin peak >35× URL, whereas for troponin levels ≤35× only spMI had a relevant impact on mortality.

Impact of Preloading Strategy With Ticagrelor on Periprocedural Myocardial Injury in Patients With Non-ST Elevation Myocardial Infarction Undergoing Early Invasive Strategy

ABSTRACT

Pretreatment with an oral P2Y12 receptor blocker (before coronary angiography) versus treatment in the catheterization laboratory has been a matter of debate in patients presenting with non-ST segment elevation myocardial infarction (NSTEMI). The primary aim of this study was to assess the impact of an immediate preloading strategy with ticagrelor on periprocedural myocardial injury in patients with NSTEMI treated with an early invasive strategy. NSTEMI patients who underwent coronary angiography and subsequent percutaneous coronary intervention (PCI) within 24 hours after hospital admission were divided into 2 groups: the first group (pretreatment group) included patients who received ticagrelor pretreatment as soon as possible after admission and the second group (no pretreatment group) included patients who received a loading dose of ticagrelor after coronary angiography. The pretreatment group included 232 patients, and the no pretreatment group included 87 patients. Male patients represented the majority of the patients. The 2 groups were similar in baseline characteristics, except for a greater incidence of hypertension ( P = 0.014) and higher hemoglobin levels ( P = 0.01) in the pretreatment group in comparison with the no pretreatment group. Patients in the ticagrelor pretreatment group had less myocardial injury until coronary angiography based on troponin measurements collected at 12 hours after admission ( P = 0.025). Patients in the ticagrelor pretreatment group also had fewer periprocedural myocardial injuries based on troponin measurements taken between 12 and 24 hours after the PCI ( P = 0.026 and P = 0.022, respectively). Our findings suggested that ticagrelor pretreatment reduces periprocedural myocardial injury in NSTEMI patients who underwent PCI within 24 hours after admission.

Frequency, Etiology, and Impact of Unplanned Repeat Coronary Angiography After ST-Elevation Myocardial Infarction

Unplanned repeat coronary angiography (CAG) after balloon angioplasty for ST-elevation myocardial infarction (STEMI) was common before the advent of coronary stenting. Limited data are available regarding the role of unplanned repeat CAG in contemporary percutaneous coronary intervention (PCI) for STEMI. Therefore, we analyzed a large, 2-center prospective STEMI registry (January 2011 to June 2020) stratified by the presence or absence of unplanned repeat CAG during index hospitalization. Patients with planned CAG for staged PCI or experimental drug administration were excluded. Among 3,637 patients with STEMI, 130 underwent unplanned repeat CAG (3.6%) during index hospitalization. These patients were more likely to have cardiogenic shock (16% vs 9.8%, p = 0.021), left anterior descending culprit (44% vs 31%, p <0.001), lower left ventricular ejection fraction (45% vs 52%, p <0.001), and higher peak troponin levels (22 vs 8 ng/ml, p <0.001) than those without repeat CAG. At repeat CAG, 80 patients had a patent stent (62%) including 65 requiring no further intervention (50%) and 15 who underwent intervention on a nonculprit lesion (12%). Only 32 patients had stent thrombosis (25%). Repeat CAG was associated with a higher incidence of recurrent MI (19% vs 0%, p <0.001) and major bleeding (12% vs 4.5%, p <0.001), yet similar in-hospital mortality (7% vs 6.4%, p = 0.93) than those without repeat CAG. In conclusion, in the era of contemporary PCI for STEMI, unplanned repeat CAG during index hospitalization was infrequent and more commonly observed in patients with left anterior descending culprit in the presence of significant left ventricular dysfunction or shock and was associated with higher in-hospital recurrent myocardial infarction and major bleeding complications.

Stenting "Vulnerable" But Fractional Flow Reserve-Negative Lesions: Potential Statistical Limitations of Ongoing and Future Trials

Can imaging provide sufficient risk stratification to warrant revascularization of a stable plaque with negative fractional flow reserve (FFR)? Prophylactic stenting could at best be applied selectively since the composite group of FFR-negative lesions has a death or myocardial infarction rate of approximately 1%/year or less but modern stents have a rate of 2% to 3.5%/year. Because vulnerable features exist in a minority of lesions, at least 9,000 patients must be screened in order to enroll a cohort with sufficient risk. While several ongoing randomized trials are testing the concept of plaque sealing in FFR-negative lesions, preventive stenting depends on such a small effect that sample sizes to validate or refute its benefit become prohibitive. Since FFR provides a quantitative, straightforward, and reproducible metric of plaque vulnerability and burden without the need for or expense of additional catheter devices, intracoronary imaging cannot meaningfully guide prophylactic stenting when faced with a negative FFR.

Assessing the Risks of Bleeding vs Thrombotic Events in Patients at High Bleeding Risk After Coronary Stent Implantation: The ARC-High Bleeding Risk Trade-off Model

Importance

Patients who are candidates for percutaneous coronary intervention (PCI) and are at high bleeding risk constitute a therapeutic challenge because they often also face an increased risk of thrombotic complications.

Objectives

To develop and validate models to predict the risks of major bleeding (Bleeding Academic Research Consortium [BARC] types 3 to 5 bleeding) and myocardial infarction (MI) and/or stent thrombosis (ST) for individual patients at high bleeding risk and provide assistance in defining procedural strategy and antithrombotic regimens.

Design, Setting, and Participants

This prognostic study used individual patient data from 6 studies conducted from July 1, 2009, to September 5, 2017, for 6641 patients at more than 200 centers in Europe, the US, and Asia who underwent PCI and were identified as being at high bleeding risk using the Academic Research Consortium criteria. In 1 year of follow-up (excluding periprocedural events), individual patient risks of MI and/or ST and major bleeding were evaluated using 33 baseline variables. To validate these models, a subgroup of 1458 patients at high bleeding risk from the ONYX ONE trial were analyzed. Statistical analysis was performed from February 1, 2019, to April 30, 2020.

Exposures

All patients underwent PCI with bare metal, drug-coated, or drug-eluting stent implants.

Main Outcomes and Measures

Forward, stepwise multivariable proportional hazards models were used to identify highly significant predictors of MI and/or ST and BARC types 3 to 5 bleeding.

Results

A total of 6641 patients (4384 men [66.0%]; median age, 77.9 years [interquartile range, 70.0-82.6 years]) were included in this study. Over 365 days, nonperiprocedural MI and/or ST occurred in 350 patients (5.3%), and BARC types 3 to 5 bleeding occurred in 381 patients (5.7%). Eight independent baseline predictors of risk of MI and/or ST and 8 predictors for risk of BARC types 3 to 5 bleeding were identified. Four of these predictors were in both risk models. Both risk models showed moderate discrimination: C statistic = 0.69 for predicting MI and/or ST and 0.68 for predicting BARC types 3 to 5 bleeding. Applying these same models to the validation cohort gave a similar strength of discrimination (C statistic = 0.74 for both MI and/or ST and BARC types 3-5 bleeding). Patients with MI and/or ST had a mortality hazard ratio of 6.1 (95% CI, 4.8-7.7), and those with BARC types 3 to 5 bleeding had a mortality hazard ratio of 3.7 (95% CI, 2.9-4.8) compared with patients free of both events. Taking these data into account, the risk scores facilitate investigation of the individual patient trade-off between these 2 risks: 2931 patients (44.1%) at high bleeding risk in the 6 studies had a greater risk of MI and/or ST than of BARC 3 to 5 bleeding, 1555 patients (23.4%) had a greater risk of BARC 3 to 5 bleeding than of MI and/or ST, and 2155 (32.4%) had a comparable risk of both events.

Conclusions and Relevance

In a large cohort of patients at high bleeding risk undergoing PCI, 2 prognostic models have been developed to identify individual patients' risk of major coronary thrombotic and bleeding events. In future clinical practice, using an application on a smartphone to evaluate the trade-off between these 2 quantifiable risks for each patient may help clinicians choose the most appropriate revascularization strategy and tailor the duration and intensity of antithrombotic regimens.

Procedural myocardial injury, infarction and mortality in patients undergoing elective PCI: a pooled analysis of patient-level data

AIMS

The prognostic importance of cardiac procedural myocardial injury and myocardial infarction (MI) in chronic coronary syndrome (CCS) patients undergoing elective percutaneous coronary intervention (PCI) is still debated.

METHODS AND RESULTS

We analysed individual data of 9081 patients undergoing elective PCI with normal pre-PCI baseline cardiac troponin (cTn) levels. Multivariate models evaluated the association between post-PCI elevations in cTn and 1-year mortality, while an interval analysis evaluated the impact of the size of the myocardial injury on mortality. Our analysis was performed in the overall population and also according to the type of cTn used [52.0% had high-sensitivity cTn (hs-cTn)]. Procedural myocardial injury, as defined by the Fourth Universal Definition of MI (UDMI) [post-PCI cTn elevation ≥1 × 99th percentile upper reference limit (URL)], occurred in 52.8% of patients and was not associated with 1-year mortality [adj odds ratio (OR), 1.35, 95% confidence interval (CI) (0.84-1.77), P = 0.21]. The association between post-PCI cTn elevation and 1-year mortality was significant starting ≥3 × 99th percentile URL. Major myocardial injury defined by post-PCI ≥5 × 99th percentile URL occurred in 18.2% of patients and was associated with a two-fold increase in the adjusted odds of 1-year mortality [2.29, 95% CI (1.32-3.97), P = 0.004]. In the subset of patients for whom periprocedural evidence of ischaemia was collected (n = 2316), Type 4a MI defined by the Fourth UDMI occurred in 12.7% of patients and was strongly associated with 1-year mortality [adj OR 3.21, 95% CI (1.42-7.27), P = 0.005]. We also present our results according to the type of troponin used (hs-cTn or conventional troponin).

CONCLUSION

Our analysis has demonstrated that in CCS patients with normal baseline cTn levels, the post-PCI cTn elevation of ≥5 × 99th percentile URL used to define Type 4a MI is associated with 1-year mortality and could be used to detect 'major' procedural myocardial injury in the absence of procedural complications or evidence of new myocardial ischaemia.

Improving the Design of Future PCI Trials for Stable Coronary Artery Disease: JACC State-of-the-Art Review

The role of percutaneous coronary interventions in addition to medical therapy for patients with stable coronary artery disease continues to be debated in routine clinical practice, despite more than 2 decades of randomized controlled trials. The residual uncertainty arises from particular challenges facing revascularization trials. Which endpoint do doctors care about, and which do patients care about? Which participants should be enrolled? What background medical therapy should we use? When is placebo control relevant? In this paper, we discuss how these questions can be approached and examine the merits and disadvantages of possible options. Engaging multiple stakeholders, including patients, researchers, regulators, and funders, to ensure the design elements are methodologically valid and clinically meaningful should be an aspirational goal in the development of future trials.

Periprocedural Myocardial Injury: Pathophysiology, Prognosis, and Prevention

The definition and clinical implications of myocardial infarction occurring in the setting of percutaneous coronary intervention have been the subject of unresolved controversy. The definitions of periprocedural myocardial infarction (PMI) are many and have evolved over recent years. Additionally, the recent advancement of different imaging modalities has provided useful information on a patients' pre-procedural risk of myocardial infarction. Nonetheless, questions on the benefit of different approaches to prevent PMI and their practical implementation remain open. This review aims to address these questions and to provide a current and contemporary perspective.

Prognostic Impact of Periprocedural Myocardial Infarction in Patients Undergoing Elective Percutaneous Coronary Interventions

BACKGROUND

The magnitude of prognostically relevant myocardial injury after percutaneous coronary interventions remains poorly defined. The Society for Cardiovascular Angiography and Interventions (SCAI) proposed marked biomarker elevations to define periprocedural myocardial infarction (PMI). These consensus-based thresholds have not been validated in the era of high-sensitivity cardiac troponins. We sought to assess the prognostic impact of SCAI-defined PMI and explore optimal prognostic thresholds of high-sensitivity cardiac troponin T (hs-cTnT) after elective percutaneous coronary interventions.

METHODS AND RESULTS

We evaluated patients who underwent elective percutaneous coronary interventions at 2 tertiary care centers with serial hs-cTnT measurements. PMI was defined as peak postprocedural hs-cTnT >70× upper reference limit (URL) in patients with nonelevated (≤1× URL) baseline levels; or incremental increase >70× URL in patients with elevated baseline levels. The primary outcome was 1-year all-cause mortality. Of 8140 patients, 220 (2.7%) died within 1 year. In multivariable analyses, patients with SCAI-defined PMI (n=140; 1.7%) had a higher risk of 1-year mortality (12.9% versus 2.5%, adjusted hazard ratio 4.10, 95% CI 2.51-6.68; P<0.001) as well as cardiac mortality (11.4% versus 2.1%, adjusted hazard ratio 4.21, 95% CI 2.50-7.11; P<0.001). Based on receiver operating characteristics analysis, the optimal prognostic threshold of hs-cTnT was >10×URL, observed in 14.6% of patients. This threshold showed lower specificity (85.7% versus 98.4%) but higher sensitivity (25.4% versus 8.2%) and better overall performance for prediction of 1-year mortality compared with the SCAI-defined cutoff value of troponin.

CONCLUSIONS

In patients undergoing elective percutaneous coronary interventions, SCAI-defined PMI emerged as an independent, highly specific, but insensitive predictor of 1-year mortality. Optimal trade-off between sensitivity and specificity was observed at a lower threshold of hs-cTnT (10× URL) in this cohort.

Central Adjudication Identified Additional and Prognostically Important Myocardial Infarctions in Patients Undergoing Percutaneous Coronary Intervention

BACKGROUND

In the CHAMPION PHOENIX trial, cangrelor reduced the primary composite end point of death, myocardial infarction (MI), ischemia-driven revascularization, or stent thrombosis at 48 hours. This study aimed to explore the impact of event adjudication and the prognostic importance of MI reported by a clinical events committee (CEC) or site investigators (SIs).

METHODS AND RESULTS

Data from the CHAMPION PHOENIX trial of patients undergoing elective or nonelective percutaneous coronary intervention were analyzed. A CEC systematically identified and adjudicated MI using predefined criteria, a computer algorithm to identify suspected events, and semilogarithmic plots to review biomarker changes. Thirty-day death was modeled using baseline characteristics. Of 10 942 patients, 462 (4.2%) patients had at least 1 MI by 48 hours identified by the CEC (207 [3.8%] cangrelor; 255 [4.7%] clopidogrel; odds ratio [OR] 0.80; 95% CI, 0.67-0.97; P=0.022), and 143 patients had at least 1 MI by 48 hours reported by the SI (60 [1.1%] cangrelor; 83 [1.5%] clopidogrel; OR, 0.72; 95% CI, 0.52-1.01; P=0.053). Of the 462 MIs identified by the CEC, 92 (20%) were reported by SI, and 370 (80%) were not. Of the 143 MI reported by the SI, 51 (36%) were not confirmed by CEC. All categories were associated with an increased adjusted risk for 30-day death (CEC: OR, 5.35; 95% CI, 2.56-11.2; P<0.001; SI: 9.08 [4.01-20.5]; P<0.001; CEC and SI: 10.9 [3.23-36.6]; P<0.001; CEC but not SI: 4.69 [1.94-11.3]; P<0.001; SI but not CEC: 15.4 [5.26-44.9]; P<0.001).

CONCLUSIONS

In patients undergoing percutaneous coronary intervention, CEC procedures identified 3 times as many MIs as the SI reported. Compared with clopidogrel, cangrelor significantly reduced MIs identified by the CEC with a qualitatively similar relative risk reduction in MIs reported by the SI. MIs identified by CEC or reported by SI were independently associated with worse 30-day death. Central adjudication identified additional, prognostically important events.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov . Unique identifier: NCT01156571.