The Gloomy Long-Term Prognosis of Patients With Type 2 Myocardial Infarction or Myocardial Injury

Characteristics and Prognosis of Type 2 Myocardial Infarction Through Worsening Renal Function and NT-proBNP in Older Adults with Pneumonia

Background

Type 2 myocardial infarction (MI) is becoming more recognized. This study aimed to assess the factors linked to type 2 MI in older adults with pneumonia and further determine the predictive factors of 90-day adverse events (refractory heart failure, cardiogenic shock, and all-cause mortality).

Methods

A single-center retrospective analysis was conducted among older adults with pneumonia. The primary outcome was the prevalence of type 2 MI. The secondary objective was to assess the adverse events in these patients with type 2 MI within 90 days.

Results

A total of 2618 patients were included. Of these, 361 patients (13.8%) suffered from type 2 MI. Multivariable predictors of type 2 MI were chronic kidney disease (CKD), age-adjusted Charlson comorbidity index (ACCI) score, and NT-proBNP > 4165pg/mL. Moreover, the independent predictive factors of 90-day adverse events included NT-proBNP > 4165pg/mL, age, ACCI score, and CKD. The Kaplan-Meier adverse events curves revealed that the type 2 MI patients with CKD and NT-proBNP > 4165pg/mL had a higher risk than CKD or NT-proBNP > 4165pg/mL alone.

Conclusion

Type 2 MI in older pneumonia hospitalization represents a heterogeneous population. Elevated NT-proBNP level and prevalence of CKD are important predictors of type 2 MI and 90-day adverse events in type 2 MI patients.

First Sampled High-Sensitive Cardiac Troponin T is Associated With One-Year Mortality in Sepsis Patients and 30- to 365-Day Mortality in Sepsis Survivors

BACKGROUND

Previous studies using cardiac troponin levels to investigate the relationship between myocardial injury and mortality in sepsis patients have been conflicting. Our aim was to investigate the relationship between plasma high-sensitive cardiac troponin T (hs-cTnT) level and 30-day and 1-year mortality in sepsis patients and 30- to 365-day mortality in sepsis survivors.

METHODS

Sepsis patients requiring vasopressor support and admitted to our institution between 2012 and 2021 (n = 586) were included in this retrospective cohort study. Elevated hs-cTnT values (≥15 ng/L) were divided into quartiles (Q): Q1 15-35 ng/L; Q2 36-61 ng/L; Q3 62-125 ng/L; Q4 126-8630 ng/L. Stratified Kaplan-Meier curves and multivariable Cox regression were used for survival analyses.

RESULTS

First sampled hs-cTnT was elevated in 529 (90%) patients. One-year mortality was 45% (n = 264). Increasing level of hs-cTnT was independently associated with higher adjusted hazard ratios (HR) for 1-year mortality compared with normal levels: Q1 HR 2.9 (95% confidence interval [CI], 1.03-8.1); Q2 HR 3.5 (95% CI, 1.2-9.8); Q3 HR 4.8 (95% CI, 1.7-13.4); Q4 HR 5.7 (95% CI, 2.1-16). In acute phase survivors, first sampled hs-cTnT was an independent predictor of 30- to 365-day mortality (HR 1.3; 95% CI, 1.1-1.6 per loge hs-cTnT).

CONCLUSIONS

First sampled plasma hs-cTnT in critically ill sepsis patients was independently associated with 30-day and 1-year mortality. Importantly, first sampled hs-cTnT was associated with mortality during the convalescence phase (30- to 365-day) and could be a feasible marker to identify acute phase survivors at high risk of death.

Assessment of Oxygen Supply-Demand Imbalance and Outcomes Among Patients With Type 2 Myocardial Infarction: A Secondary Analysis of the High-STEACS Cluster Randomized Clinical Trial

Importance

Type 2 myocardial infarction occurs owing to multiple factors associated with myocardial oxygen supply-demand imbalance, which may confer different risks of adverse outcomes.

Objective

To evaluate the prevalence and outcomes of different factors associated with oxygen supply-demand imbalance among patients with type 2 myocardial infarction.

Design, Setting, and Participants

In this secondary analysis of a stepped-wedge, cluster randomized clinical trial conducted at 10 secondary and tertiary care hospitals in Scotland, 6096 patients with an adjudicated diagnosis of type 1 or type 2 myocardial infarction from June 10, 2013, to March 3, 2016, were identified, and the findings were reported on August 28, 2018. The trial enrolled consecutive patients with suspected acute coronary syndrome. The diagnosis of myocardial infarction was adjudicated according to the Fourth Universal Definition of Myocardial Infarction and the primary factor associated with oxygen supply-demand imbalance in type 2 myocardial infarction was defined. This secondary analysis was not prespecified. Statistical analysis was performed from July 7 to 30, 2020.

Intervention

Implementation of a high-sensitivity cardiac troponin I assay.

Main Outcomes and Measures

All-cause death at 1 year according to the factors associated with oxygen supply-demand imbalance among patients with type 2 myocardial infarction.

Results

Of 6096 patients (2602 women [43%]; median age, 70 years [IQR, 58-80 years]), 4981 patients had type 1 myocardial infarction, and 1115 patients had type 2 myocardial infarction. The most common factor associated with oxygen supply-demand imbalance was tachyarrhythmia (616 of 1115 [55%]), followed by hypoxemia (219 of 1115 [20%]), anemia (95 of 1115 [9%]), hypotension (89 of 1115 [8%]), severe hypertension (61 of 1115 [5%]), and coronary mechanisms (35 of 1115 [3%]). At 1 year, all-cause mortality occurred for 15% of patients (720 of 4981) with type 1 myocardial infarction and 23% of patients (285 of 1115) with type 2 myocardial infarction. Compared with patients with type 1 myocardial infarction, those with type 2 myocardial infarction owing to hypoxemia (adjusted odds ratio [aOR], 2.35; 95% CI, 1.72-3.18) and anemia (aOR, 1.83; 95% CI, 1.14-2.88) were at greatest risk of death, whereas those with type 2 myocardial infarction owing to tachyarrhythmia (aOR, 0.83; 95% CI, 0.65-1.06) or coronary mechanisms (aOR, 1.07; 95% CI, 0.17-3.86) were at similar risk of death as patients with type 1 myocardial infarction.

Conclusions and Relevance

In this secondary analysis of a randomized clinical trial, mortality after type 2 myocardial infarction was associated with the underlying etiologic factor associated with oxygen supply-demand imbalance. Most type 2 myocardial infarctions were associated with tachyarrhythmia, with better prognosis, whereas hypoxemia and anemia accounted for one-third of cases, with double the mortality of type 1 myocardial infarction. These differential outcomes should be considered by clinicians when determining which cases need to be managed if patient outcomes are to improve.

Trial Registration

ClinicalTrials.gov Identifier: NCT01852123.

Type 2 MI and Myocardial Injury in the Era of High-sensitivity Troponin

Troponin has been the cornerstone of the definition of MI since its introduction to clinical practice. High-sensitivity troponin has allowed clinicians to detect degrees of myocardial damage at orders of magnitude smaller than previously and is challenging the definitions of MI, with implications for patient management and prognosis. Detection and diagnosis are no doubt enhanced by the greater sensitivity afforded by these markers, but perhaps at the expense of specificity and clarity. This review focuses on the definitions, pathophysiology, prognosis, prevention and management of type 2 MI and myocardial injury. The five types of MI were first defined in 2007 and were recently updated in 2018 in the fourth universal definition of MI. The authors explore how this pathophysiological classification is used in clinical practice, and discuss some of the unanswered questions in this era of availability of high-sensitivity troponin.

High-Sensitivity Troponin T Testing for Pediatric Patients in the Emergency Department

Debate exists on the usefulness of high-sensitivity cardiac troponin (hs-cTn) testing in pediatric patients due to the perceived low incidence of myocardial injury and lack of data concerning its efficacy. We evaluated the contribution of an increased hs-cTnT above the 99th percentile upper-reference limit (URL) to clinical diagnoses made in pediatric patients presenting to the emergency department (ED). Retrospective cohort study including patients aged 0-18 years presenting to the ED from 2018 to 2020 where hs-cTnT was measured. Sex-specific 99th percentile URLs of 15 and 10 ng/L for males and females, respectively, were used, with concentrations above these thresholds considered indicative of myocardial injury. Overall, 356 patients were identified in whom hs-cTnT concentrations were measured during ED clinical evaluation. Hs-cTnT was increased above the 99th percentile on presentation in 36 patients (10.1%). Twelve patients (3.4%) had a clinical cardiac diagnosis made. Hs-cTnT was increased in 6 of these (50.0%). Serial hs-cTnT from 106 patients with an initial hs-cTnT < 99th percentile was subsequently elevated in 5 (4.6%); none of whom had a final clinical cardiac diagnosis. Hs-cTnT has high specificity, but low sensitivity when used as a screening tool for myocardial injury when the gold standard is mostly clinical assessment. In present practice, however, they do not appear to track well with clinical diagnoses. Further studies are needed to more clearly define the role of hs-cTnT in this patient population.

Myocardial Infarction in the ISCHEMIA Trial: Impact of Different Definitions on Incidence, Prognosis, and Treatment Comparisons

BACKGROUND

In the ISCHEMIA trial (International Study of Comparative Health Effectiveness with Medical and Invasive Approaches), an initial invasive strategy did not significantly reduce rates of cardiovascular events or all-cause mortality in comparison with a conservative strategy in patients with stable ischemic heart disease and moderate/severe myocardial ischemia. The most frequent component of composite cardiovascular end points was myocardial infarction (MI).

METHODS

ISCHEMIA prespecified that the primary and major secondary composite end points of the trial be analyzed using 2 MI definitions. For procedural MI, the primary MI definition used creatine kinase-MB as the preferred biomarker, whereas the secondary definition used cardiac troponin. Procedural thresholds were >5 times the upper reference level for percutaneous coronary intervention and >10 times for coronary artery bypass grafting. Procedural MI definitions included (1) a category of elevated biomarker only events with much higher biomarker thresholds, (2) new ST-segment depression of ≥1 mm for the primary and ≥0.5 mm for the secondary definition, and (3) new coronary dissections >National Heart, Lung, and Blood Institute grade 3. We compared MI type, frequency, and prognosis by treatment assignment using both MI definitions.

RESULTS

Procedural MIs accounted for 20.1% of all MI events with the primary definition and 40.6% of all MI events with the secondary definition. Four-year MI rates in patients undergoing revascularization were more frequent with the invasive versus conservative strategy using the primary (2.7% versus 1.1%; adjusted hazard ratio [HR], 2.98 [95% CI, 1.87-4.73]) and secondary (8.2% versus 2.0%; adjusted HR, 5.04 [95% CI, 3.64-6.97]) MI definitions. Type 1 MIs were less frequent with the invasive versus conservative strategy using the primary (3.40% versus 6.89%; adjusted HR, 0.53 [95% CI, 0.41-0.69]; P<0.0001) and secondary (3.48% versus 6.89%; adjusted HR, 0.53 [95% CI, 0.41-0.69]; P<0.0001) definitions. The risk of subsequent cardiovascular death was higher after a type 1 MI than after no MI using the primary (adjusted HR, 3.38 [95% CI, 2.03-5.61]; P<0.001) or secondary MI definition (adjusted HR, 3.52 [2.11-5.88]; P<0.001).

CONCLUSIONS

In ISCHEMIA, type 1 MI events using the primary and secondary definitions during 5-year follow-up were more frequent with an initial conservative strategy and associated with subsequent cardiovascular death. Procedural MI rates were greater in the invasive strategy and with the use of the secondary MI definition. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01471522.