Have We Overdefined Periprocedural Myocardial Infarction to the Point of Extinction?

Periprocedural myocardial infarction after percutaneous coronary intervention and long-term mortality: a meta-analysis

BACKGROUND AND AIMS

Conflicting data are available regarding the association between periprocedural myocardial infarction (PMI) and mortality following percutaneous coronary intervention. The purpose of this study was to evaluate the incidence and prognostic implication of PMI according to the Universal Definition of Myocardial Infarction (UDMI), the Academic Research Consortium (ARC)-2 definition, and the Society for Cardiovascular Angiography and Interventions (SCAI) definition.

METHODS

Studies reporting adjusted effect estimates were systematically searched. The primary outcome was all-cause death, while cardiac death was included as a secondary outcome. Studies defining PMI according to biomarker elevation without further evidence of myocardial ischaemia ('ancillary criteria') were included and reported as 'definition-like'. Data were pooled in a random-effect model.

RESULTS

A total of 19 studies and 109 568 patients were included. The incidence of PMI was progressively lower across the UDMI, ARC-2, and SCAI definitions. All PMI definitions were independently associated with all-cause mortality [UDMI: hazard ratio (HR) 1.61, 95% confidence interval (CI) 1.32-1.97; I2 34%; ARC-2: HR 2.07, 95% CI 1.40-3.08, I2 0%; SCAI: HR 3.24, 95% CI 2.36-4.44, I2 78%]. Including ancillary criteria in the PMI definitions were associated with an increased prognostic performance in the UDMI but not in the SCAI definition. Data were consistent after evaluation of major sources of heterogeneity.

CONCLUSIONS

All currently available international definitions of PMI are associated with an increased risk of all-cause death after percutaneous coronary intervention. The magnitude of this latter association varies according to the sensitivity and prognostic relevance of each definition.

Effect of Periprocedural Myocardial Infarction After Initial Revascularization With Left Main PCI in Patients With Recent Myocardial Infarction

Background

Periprocedural myocardial infarction (PMI) after percutaneous coronary intervention (PCI) for left main coronary artery disease (LMCAD) may be particularly deleterious in patients with recent myocardial infarction (MI). We sought to determine the rates and prognostic relevance of PMI using different definitions and biomarker thresholds after PCI for LMCAD in patients with recent MI.

Methods

Between January 2004 and December 2016, 442 patients underwent PCI for LMCAD at a median of 3 days after presentation with MI. A total of 350 patients presented with elevated cardiac biomarker levels (349 with serial creatine kinase-myocardial band [CK-MB] and 219 with serial cardiac troponin I (cTnI) values) that were stable or falling before the PCI. In this cohort, PMI within 48 hours of PCI was adjudicated using Society for Cardiovascular Angiography & Interventions (SCAI), Academic Research Consortium 2 (ARC-2), and fourth Universal Definition of Myocardial Infarction (UDMI) criteria. The primary and secondary end points were 3-year rates of cardiovascular (CV) and all-cause death.

Results

An incremental post-PCI rise in CK-MB starting at ≥10× the upper reference limit from baseline was significantly associated with 3-year CV death (adjusted hazard ratio [aHR], 7.96; 95% confidence interval [CI], 2.89-21.90), whereas CV death was not associated with any threshold elevation of cTnI. The frequencies of PMI according to the fourth UDMI, ARC-2, and SCAI definitions were 19.4%, 12.3%, and 8.6%, respectively. PMI by all 3 definitions was significantly associated with 3-year CV death, with the SCAI definition having the strongest relationship (aHR, 6.34; 95% CI, 2.47-16.27) compared with those of ARC-2 (aHR, 2.82; 95% CI, 1.15-6.96) and fourth UDMI (aHR, 2.65; 95% CI, 1.14-6.14).

Conclusions

In patients with recent MI undergoing PCI for LMCAD, an incremental elevation in postprocedural CK-MB of ≥10× the upper reference limit as a stand-alone measure was strongly predictive of 3-year CV and all-cause death, whereas no cTnI elevations of any level were prognostic. All 3 contemporary PMI definitions in widespread use were associated with 3-year mortality after PCI in this high-risk cohort, with the SCAI definition having the strongest relationship with subsequent death.

Percutaneous coronary intervention with drug-eluting stents versus coronary artery bypass grafting in left main coronary artery disease: an individual patient data meta-analysis

BACKGROUND

The optimal revascularisation strategy for patients with left main coronary artery disease is uncertain. We therefore aimed to evaluate long-term outcomes for patients treated with percutaneous coronary intervention (PCI) with drug-eluting stents versus coronary artery bypass grafting (CABG).

METHODS

In this individual patient data meta-analysis, we searched MEDLINE, Embase, and the Cochrane database using the search terms "left main", "percutaneous coronary intervention" or "stent", and "coronary artery bypass graft*" to identify randomised controlled trials (RCTs) published in English between database inception and Aug 31, 2021, comparing PCI with drug-eluting stents with CABG in patients with left main coronary artery disease that had at least 5 years of patient follow-up for all-cause mortality. Two authors (MSS and BAB) identified studies meeting the criteria. The primary endpoint was 5-year all-cause mortality. Secondary endpoints were cardiovascular death, spontaneous myocardial infarction, procedural myocardial infarction, stroke, and repeat revascularisation. We used a one-stage approach; event rates were calculated by use of the Kaplan-Meier method and treatment group comparisons were made by use of a Cox frailty model, with trial as a random effect. In Bayesian analyses, the probabilities of absolute risk differences in the primary endpoint between PCI and CABG being more than 0·0%, and at least 1·0%, 2·5%, or 5·0%, were calculated.

FINDINGS

Our literature search yielded 1599 results, of which four RCTs-SYNTAX, PRECOMBAT, NOBLE, and EXCEL-meeting our inclusion criteria were included in our meta-analysis. 4394 patients, with a median SYNTAX score of 25·0 (IQR 18·0-31·0), were randomly assigned to PCI (n=2197) or CABG (n=2197). The Kaplan-Meier estimate of 5-year all-cause death was 11·2% (95% CI 9·9-12·6) with PCI and 10·2% (9·0-11·6) with CABG (hazard ratio 1·10, 95% CI 0·91-1·32; p=0·33), resulting in a non-statistically significant absolute risk difference of 0·9% (95% CI -0·9 to 2·8). In Bayesian analyses, there was an 85·7% probability that death at 5 years was greater with PCI than with CABG; this difference was more likely than not less than 1·0% (<0·2% per year). The numerical difference in mortality was comprised more of non-cardiovascular than cardiovascular death. Spontaneous myocardial infarction (6·2%, 95% CI 5·2-7·3 vs 2·6%, 2·0-3·4; hazard ratio [HR] 2·35, 95% CI 1·71-3·23; p<0·0001) and repeat revascularisation (18·3%, 16·7-20·0 vs 10·7%, 9·4-12·1; HR 1·78, 1·51-2·10; p<0·0001) were more common with PCI than with CABG. Differences in procedural myocardial infarction between strategies depended on the definition used. Overall, there was no difference in the risk of stroke between PCI (2·7%, 2·0-3·5) and CABG (3·1%, 2·4-3·9; HR 0·84, 0·59-1·21; p=0·36), but the risk was lower with PCI in the first year after randomisation (HR 0·37, 0·19-0·69).

INTERPRETATION

Among patients with left main coronary artery disease and, largely, low or intermediate coronary anatomical complexity, there was no statistically significant difference in 5-year all-cause death between PCI and CABG, although a Bayesian approach suggested a difference probably exists (more likely than not <0·2% per year) favouring CABG. There were trade-offs in terms of the risk of myocardial infarction, stroke, and revascularisation. A heart team approach to communicate expected outcome differences might be useful to assist patients in reaching a treatment decision.

FUNDING

No external funding.

The value of perioperative biomarker release for the assessment of myocardial injury or infarction in cardiac surgery

OBJECTIVES

Cardiac biomarkers are indicators of irreversible cell damage. Current myocardial infarction (MI) definitions require concomitant clinical characteristics. For perioperative MI, a correlation of biomarker elevations and mortality has been suggested. Definitions emerged relying on cardiac biomarker release only. This approach is questionable as several clinical and experimental scenarios exist where relevant biomarker release can occur apart from MI.

METHODS

We reviewed the clinical and basic science literature and revealed important aspects regarding the use and interpretation of cardiac biomarker release with special focus on their interpretation in the perioperative setting.

RESULTS

Ischaemic biomarkers may be released without cell death in multiple conditions, such as after endurance runs in athletes, temporary inotropic stimulation in animal models and flow variations in in vitro cell models. In addition, access through atrial tissue during cannulation or concomitant valve procedures adds sources of enzyme release that may not be related to ventricular ischaemia (i.e. MI). Such non-cell death-related mechanisms may explain the lack of poor correlations of enzyme release and long-term outcomes in recent trials. In addition, the 3 main biomarkers, troponin T, I and creatine kinase myocardial band, differ in their release kinetics, which may differentially trigger MI events in trial patients.

CONCLUSIONS

The identification of irreversible myocardial injury in cardiac surgery based only on biomarker release is unreliable. Cell death- and non-cell death-related mechanisms create a mix in the perioperative setting that requires additional markers for proper identification of MI. In addition, the 3 most common ischaemic biomarkers display different release kinetics adding to the confusion. We review the topic.

SUBJ COLLECTION

120, 123.