Type 2 versus type 1 myocardial infarction: a comparison of clinical characteristics and outcomes with a meta-analysis of observational studies

Differences between MINOCA and type 2 myocardial infarction: An ITALIAN observational study

BACKGROUND

Myocardial infarction with non-obstructive coronary arteries (MINOCA) and type 2 myocardial infarction (MI), both presenting as non-ST-elevation MI (NSTEMI), are often grouped together due to overlapping symptoms. The aim of our study is to compare their characteristics and prognosis to distinguish between them.

METHODS

Among 7815 patients with NSTEMI who underwent coronary angiography between 2005 and 2022 we identified 538 patients with diagnosis of MINOCA (n = 301; 3,9 %) and type 2 MI (n = 237; 3 %). The outcome was a composite of all-cause mortality, non-fatal MI, hospitalisation for heart failure (HF) and transitory ischemic attack or non-fatal stroke.

RESULTS

The mean age of the entire cohort was 68 (11.5) years, with women being the most frequently represented group (65 %). Comparing the sub-cohorts, MINOCA patients were younger (66.3 (11.7) Vs. 70.6 (11) years, p < 0.01), and less likely to have typical cardiovascular risk than type 2 MI patients. At multivariable analysis different clinical (age, heart rate, typical chest pain, palpitations, postmenopausal status), and instrumental (cardiac rhythm, ST-segment changes, diastolic dysfunction, hypo/akinesia with non-coronary distribution) variables were independent predictors of MINOCA with AUC of 0.83 [95 % CI, 0.78-0.88], p < 0.01 at ROC analysis. At a median follow-up of 61 (IQR 34-100) months, MINOCA patients had significantly lower rate of the composite endpoint compared to type 2 MI (20 % Vs. 32 %, p < 0.01).

CONCLUSIONS

MINOCA cohort was associated with different characteristics compared to type 2 MI and had a better prognosis despite the number of events was not negligible.

Association between kidney function, frailty and receipt of invasive management after acute coronary syndrome

BACKGROUND

Reduced estimated glomerular filtration rate (eGFR) is associated with lower use of invasive management and increased mortality after acute coronary syndrome (ACS). The reasons for this are unclear.

METHODS

A retrospective clinical cohort study was performed using data from the English National Institute for Health Research Health Informatics Collaborative (2010-2017). Multivariable logistic regression was used to investigate whether eGFR<90 mL/min/1.73 m2 was associated with conservative ACS management and test whether (a) differences in care could be related to frailty and (b) associations between eGFR and mortality could be related to variation in revascularisation rates.

RESULTS

Among 10 205 people with ACS, an eGFR of <60 mL/min/1.73m2 was found in 25%. Strong inverse linear associations were found between worsening eGFR category and receipt of invasive management, on a relative and absolute scale. People with an eGFR <30 mL compared with ≥90 mL/min/1.73 m2 were half as likely to receive coronary angiography (OR 0.50, 95% CI 0.40 to 0.64) after non-ST-elevation (NSTE)-ACS and one-third as likely after STEMI (OR 0.30, 95% CI 0.19 to 0.46), resulting in 15 and 17 per 100 fewer procedures, respectively. Following multivariable adjustment, the ORs for receipt of angiography following NSTE-ACS were 1.05 (95% CI 0.88 to 1.27), 0.98 (95% CI 0.77 to 1.26), 0.76 (95% CI 0.57 to 1.01) and 0.58 (95% CI 0.44 to 0.77) in eGFR categories 60-89, 45-59, 30-44 and <30, respectively. After STEMI, the respective ORs were 1.20 (95% CI 0.84 to 1.71), 0.77 (95% CI 0.47 to 1.24), 0.33 (95% CI 0.20 to 0.56) and 0.28 (95% CI 0.16 to 0.48) (p<0.001 for linear trends). ORs were unchanged following adjustment for frailty. A positive association between the worse eGFR category and 30-day mortality was found (test for trend p<0.001), which was unaffected by adjustment for frailty.

CONCLUSIONS

In people with ACS, lower eGFR was associated with reduced receipt of invasive coronary management and increased mortality. Adjustment for frailty failed to change these observations. Further research is required to explain these disparities and determine whether treatment variation reflects optimal care for people with low eGFR.

TRIAL REGISTRATION NUMBER

NCT03507309.

[Acute ischemic stroke and troponin elevation: update of the Mannheim clinical algorithm]

Elevated high-sensitivity cardiac troponin (hs-cTn) levels should be expected in about half of all patients with acute ischemic stroke (AIS). Since those patients are at risk of increased morbidity and mortality, often attributable to cardiac causes, an adequate work-up of the underlying etiology is required. This can only be achieved by a team of cardiologists and neurologists. Since underlying causes of hs-cTn elevation in AIS patients are diverse, often atypical or silent in their clinical presentation and some, such as an accompanying myocardial infarction, can be acutely life-threatening, the work-up should follow a standardized clinical algorithm. The vast majority of hs-cTn elevations are caused by non-ischemic myocardial injury associated with AIS. This work presents a practice-oriented approach to differential diagnosis with the update of the Mannheim clinical algorithm for acute ischemic stroke and troponin elevation.

Treatment and outcomes of patients with chronic lung disease and acute myocardial infarction: Insights from the nationwide AMIS plus registry

BACKGROUND

Limited data are available on patients with chronic lung disease (CLD) presenting with acute myocardial infarction (AMI). We aimed to analyse baseline characteristics, treatment and outcome of those patients enrolled in the Swiss nationwide prospective AMIS Plus registry.

METHODS

All AMI patients enrolled between January 2002 and December 2021 with data on CLD, as defined in the Charlson Comorbidity Index, were included. The primary endpoints were in-hospital mortality and major adverse cardiac and cerebrovascular events (MACCE), defined as all-cause death, reinfarction and cerebrovascular events. Baseline characteristics, in-hospital treatments and outcomes were analysed using descriptive statistics and logistic regression.

RESULTS

Among 53,680 AMI patients enrolled during this time, 5.8% had CLD. Compared with patients without CLD, CLD patients presented more frequently with non-ST-elevation myocardial infarction (MI) and type 2 MI (12.8% vs. 6.5%, p < 0.001). With respect to treatment, CLD patients were less likely to receive P2Y12 inhibitors (p < 0.001) and less likely to undergo percutaneous coronary interventions (68.7% vs. 82.5%; p < 0.001). In-hospital mortality declined in AMI patients with CLD over time (from 12% in 2002 to 7.3% in 2021). Multivariable regression analysis showed that CLD was an independent predictor for MACCE (adjusted OR was 1.28 [95% CI 1.07-1.52], p = 0.006).

CONCLUSION

Patients with CLD and AMI were less likely to receive evidence-based pharmacologic treatments, coronary revascularization and had a higher incidence of MACCE during their hospital stay compared to those without CLD. Over 20 years, in-hospital mortality was significantly reduced in AMI patients, especially in those with CLD.

Prevalence, Predictors, and Outcomes of Type 2 NSTEMI in Hospitalized Patients With COVID-19

BACKGROUND

Data on the incidence of type 2 non-ST-segment-elevation myocardial infarction (T2MI) in hospitalized patients with COVID-19 has been limited to single-center studies. Given that certain characteristics, such as obesity and type 2 diabetes, have been associated with higher mortality in COVID-19 infections, we aimed to define the incidence of T2MI in a national cohort and identify pre-hospital patient characteristics associated with T2MI in hospitalized patients with COVID-19.

METHODS AND RESULTS

Using the national American Heart Association COVID-19 Cardiovascular Disease Quality Improvement Registry, we performed a retrospective 4:1 matched (age, sex, race, and body mass index) analysis of controls versus cases with T2MI. We performed (1) conditional multivariable logistic regression to identify predictive pre-hospital patient characteristics of T2MI for patients hospitalized with COVID-19 and (2) stratified proportional hazards regression to investigate the association of T2MI with morbidity and mortality. From January 2020 through May 2021, there were 709 (2.2%) out of 32 015 patients with T2MI. Five hundred seventy-nine cases with T2MI were matched to 2171 controls (mean age 70; 43% female). Known coronary artery disease, heart failure, chronic kidney disease, hypertension, payor source, and presenting heart rate were associated with higher odds of T2MI. Anti-hyperglycemic medication and anti-coagulation use before admission were associated with lower odds of T2MI. Those with T2MI had higher morbidity and mortality (hazard ratio, 1.40 [95% CI, 1.13-1.74]; P=0.002).

CONCLUSIONS

In hospitalized patients with COVID-19, those with a T2MI compared with those without had higher morbidity and mortality. Outpatient anti-hyperglycemic and anti-coagulation use were the only pre-admission factors associated with reduced odds of T2MI.

Myocardial oxygen supply and demand imbalance predicts mortality in older nursing home residents: The PARTAGE study

BACKGROUND

A mismatch between myocardial oxygen supply and demand is the most common cause of ischemic myocardial injury in older persons. The subendocardial viability ratio (SEVR) can usefully estimate the degree of myocardial perfusion relative to left-ventricular workload. The aim of the present study was to evaluate the ability of SEVR to predict long-term mortality in the older population. Additionally, we aimed to identify the SEVR cutoff value best predicting total mortality.

METHODS

This is a multicenter, longitudinal study involving a large population of individuals older than 80 years living in nursing homes. Patients with cancer, severe dementia, and very low level of autonomy were excluded from the study. Participants were monitored for 10 years. Adverse outcomes were recorded every 3 months from inclusion to the end of the study. SEVR reflects the balance between subendocardial oxygen supply and demand, and was estimated non-invasively by analyzing the carotid pressure waveform recorded by applanation arterial tonometry.

RESULTS

A total of 828 people were enrolled (mean age: 87.7 ± 4.7 years, 78% female). 735 patients died within 10 years and 24 were lost to follow-up. SEVR was inversely associated with mortality at univariate Cox-regression model (risk ratio, 0.683 per unit increase in SEVR; 95% confidence interval (CI) [0.502-0.930], p = 0.015) and in a model including age, sex, body mass index, Activity of Daily Living index and Mini-Mental State Examination score (risk ratio, 0.647; 95% CI [0.472-0.930]). The lowest tertile of SEVR was associated with higher 10-years total mortality than the middle (p < 0.001) and the highest (p < 0.004) tertile. A SEVR cutoff value of 83% was identified as the best predictor of total mortality.

CONCLUSIONS

SEVR may be considered as a marker of "cardiovascular frailty." An accurate non-invasive estimation of SEVR could be a useful and independent parameter to assess survival probability in very old adults.

TRIAL REGISTRATION

NCT00901355, registered on ClinicalTrials.gov website.

Management and Outcomes of Type I and Type II Myocardial Infarction in Cardiogenic Shock

Background

Type I myocardial infarction (T1MI) or type II myocardial infarction (T2MI) have different underlying mechanisms; however, in the setting of cardiogenic shock (CS), it is not understood if patients experience resultantly different outcomes. The objective of this study was to determine clinical features, biomarker patterns, and outcomes in these subgroups.

Methods

Patients from the CAPITAL-DOREMI trial presenting with acute myocardial infarction-associated CS (n = 103) were classified as T1MI (n = 61) or T2MI (n = 42). The primary endpoint was a composite of all-cause in-hospital mortality, cardiac arrest, the need for mechanical circulatory support, or initiation of renal replacement therapy at 30 days. Secondary endpoints were evaluated as individual components of the primary endpoint.

Results

Patients with T1MI CS did not have a higher incidence of the primary composite endpoint compared with T2MI CS (adjusted hazard ratio [HR], 1.63; 95% confidence interval [CI], 0.96-2.77; P = 0.07). Cardiac biomarkers including troponin I (P < 0.001), and creatine kinase levels (P = 0.001) were elevated in patients with T1MI CS compared with T2MI. Furthermore, patients with T1MI CS presented with decreased urine output (P = 0.01) compared with T2MI. Predictors of T2MI CS included nonischemic ventricular dysfunction (P = 0.002), atrial fibrillation (P = 0.02), and chronic obstructive pulmonary disease (P = 0.002).

Conclusions

There were no differences in adverse clinical outcomes between patients with T1MI and T2MI CS, although the events were numerically increased, and the sample size was small. Overall, this study provides a hypothesis-generating analysis regarding the clinical and biochemical outcomes in T1MI vs T2MI CS.

Occult myocardial injury is prevalent amongst elderly patients in the hospital-at-home setting. A retrospective analysis of 213 patients

Background

Hospital-at-Home (HAH) is a valid alternative for in-hospital stay for a wide variety of clinical indications. Occult myocardial injury, associated with acute illness, mainly occurs in patients with a background of non-obstructive coronary disease. The aim of this study was to describe the prevalence of this phenomenon in our HAH population.

Methods

A retrospective description and analysis of data collected for patients admitted to the Sheba beyond's HAH services during 14 months.

Results

During a period of 14 months (7/10/21-6/12/22), blood troponin measurements were available for 213 patients (median age 78 years, 52% males) hospitalized mainly for infectious causes. The median HS (highly sensitive) troponin level was 7.7 ng/L (IQR = 13.2 ng/L) (the normal upper limit is 12 ng/L) with 31% of all patients demonstrating an abnormally increased troponin level (68/213). Of all patients, 64% had a background diagnosis of a cardiovascular disease (138/213), of whom, 49% had abnormal HS troponin levels (68/138). No patient suffered from acute cardiac function deterioration and no patient died during their hospital-at-home stay.

Conclusion

The prevalence of occult myocardial injury amongst elderly patients admitted to hospital-at-home stay for diagnoses other than myocardial infarction is relatively high but it is not associated with worse short-term clinical outcomes.

Comparison between In-Hospital and Out-of-Hospital Acute Myocardial Infarctions: Results from the Regional Myocardial Infarction Registry of Saxony-Anhalt (RHESA) Study

AIMS

Risk factors and outcomes of in-hospital ST elevation myocardial infraction (STEMI) are well explored. Recent findings show that non-ST elevation myocardial infarction (NSTEMI) accounts for the majority of in-hospital infarctions (IHMIs). Our aim was to identify differences between IHMI and out-of-hospital myocardial infraction (OHMI) in terms of risk factors, treatment and outcomes, including both STEMI and NSTEMI.

METHODS

We analyzed the Regional Myocardial Infarction Registry of Saxony-Anhalt dataset. Patient characteristics, treatments and outcomes were compared between IHMI and OHMI. The association between clinical outcomes and myocardial infarction type was assessed using generalized additive models.

RESULTS

Overall, 11.4% of the included myocardial infractions were IHMI, and the majority were NSTEMI. Patients with IHMI were older and had more comorbidities than those with OHMI. Compared to OHMI, in-hospital myocardial infarction was associated with higher odds of 30-day mortality (OR = 1.85, 95% CI 1.32-2.59) and complications (OR = 2.36, 95 % CI 1.84-3.01).

CONCLUSIONS

We provided insights on the full spectrum of IHMI, in both of its classifications. The proportion of IHMI was one ninth of all AMI cases treated in the hospital. Previously reported differences in the baseline characteristics and treatments, as well as worse clinical outcomes, in in-hospital STEMI compared to out-of-hospital STEMI persist even when including NSTEMI cases.

Outcomes of Patients With Takotsubo Syndrome Compared With Type 1 and Type 2 Myocardial Infarction

Background Takotsubo syndrome (TS) and myocardial infarction (MI) share similar clinical and laboratory characteristics but have important differences in causes, demographics, management, and outcomes. Methods and Results In this observational study, the National Inpatient Sample and National Readmission Database were used to identify patients admitted with TS, type 1 MI, or type 2 MI in the United States between October 1, 2017, and December 31, 2019. We compared patients hospitalized with TS, type 1 MI, and type 2 MI with respect to key features and outcomes. Over the 27-month study period, 2 035 055 patients with type 1 MI, 639 075 patients with type 2 MI, and 43 335 patients with TS were identified. Cardiac arrest, ventricular fibrillation, and ventricular tachycardia were more prevalent in type 1 MI (4.02%, 3.2%, and 7.2%, respectively) compared with both type 2 MI (2.8%, 0.8%, and 5.4% respectively) and TS (2.7%, 1.8%, and 5.3%, respectively). Risk of mortality was lower in TS compared with both type 1 MI (3.3% versus 7.9%; adjusted odds ratio [OR], 0.3; P<0.001) and type 2 MI (3.3% versus 8.2%; adjusted OR, 0.3; P<0.001). Mortality rate (OR, 1.2; P<0.001) and cardiac-cause 30-day readmission rate (adjusted OR, 1.7; P<0.001) were higher in type 1 MI than in type 2 MI. Conclusions Patients with type 1 MI had the highest rates of in-hospital mortality and cardiac-cause 30-day readmission. Risk of all-cause 30-day readmission was highest in patients with type 2 MI. The risk of ventricular arrhythmias in patients with TS is lower than in patients with type 1 MI but higher than in patients with type 2 MI.

Clinical outcomes associated with type II myocardial infarction caused by bleeding

BACKGROUND

Type ll myocardial infarction (T2MI) is caused by a mismatch between myocardial oxygen supply and demand. One subset of individuals is T2MI caused by acute hemorrhage. Traditional MI treatments including antiplatelets, anticoagulants, and revascularization can worsen bleeding. We aim to report outcomes of T2MI patients due to bleeding, stratified by treatment approach.

METHODS

The MGB Research Patient Data Registry followed by manual physician adjudication was used to identify individuals with T2MI caused by bleeding between 2009 and 2022. We defined 3 treatment groups: (1) invasively managed, (2) pharmacologic, and (3) conservatively managed Clinical parameters and outcomes for 30-day, mortality, rebleeding, and readmission were abstracted compared between the treatment groups.

RESULTS

We identified 5,712 individuals coded with acute bleeding, of which 1,017 were coded with T2MI during their admission. After manual physician adjudication, 73 individuals met the criteria for T2MI caused by bleeding. 18 patients were managed invasively, 39 received pharmacologic therapy alone, and 16 were managed conservatively. The invasively managed group experienced lower mortality (P = .021) yet higher readmission (P = .045) than the conservatively managed group. The pharmacologic group also experienced lower mortality (P= .017) yet higher readmission (P = .005) than the conservatively managed group.

CONCLUSION

Individuals with T2MI associated with acute hemorrhage are a high-risk population. Patients treated with standard procedures experienced higher readmission but lower mortality than conservatively managed patients. These results raise the possibility of testing ischemia-reduction approaches for such high-risk populations. Future clinical trials are required to validate treatment strategies for T2MI caused by bleeding.

The Presence of Pneumonia Is Strongly Associated With Higher Prevalence of Non-ST-Elevation Myocardial Infarction Using a Large NIS Database

OBJECTIVE

Inflammation is a risk factor for myocardial infarction. Pneumonia leads to severe inflammatory response. Some studies suggest higher risk of myocardial infarction in patients with pneumonia. We used a large inpatient database (National Inpatient Sample) to evaluate this association.

METHODS

This study includes patients from a Nationwide Inpatient Sample hospital in 2005 to 2014 with International Classification of Diseases, Ninth Revision, and Clinical Modification codes consistent with pneumonia and non-ST elevation myocardial infarction (NSTEMI). Subjects were stratified into all hospitalized patients aged 30 and above. Univariate and multivariate analysis was performed adjusting for age, race, gender, tobacco use, diabetes mellitus, hypertension, and hyperlipidemia.

RESULTS

NSTEMI was present in 3.2% of pneumonia patients versus 1.8% in the non-pneumonia population over 10-year period. For example, the 2005 database: [odds ratio (OR), 1.77; 95% confidence interval (CI), 1.73-1.80; P < 0.001]. For 2014, NSTEMI was present in 4.1% of pneumonia patients (PNA) versus 2.4% in the non-pneumonia population (OR, 1.72; 95% CI, 1.70-1.75; P < 0.001). NSTEMI remained independently associated with pneumonia following a multivariate analysis in 2005 (OR, 1.477; 95% CI, 1.447-1.508; P < 0.001) with a similar value in 2014 (OR, 1.445; 95% CI, 1.421-1.469; P < 0.001).

CONCLUSIONS

Using a large inpatient database, we found that NSTEMI was strongly associated with PNA versus non-pneumonia population over a 10-year period. Suggesting acute inflammatory cytokines or hypoxia which occurs during lung infection may play a role in NSTEMI development, reinforcing the importance of acute cardiac monitoring in patients with PNA.

Associations between alcohol and cigarette use and type 1 and 2 myocardial infarction among people with HIV

OBJECTIVES

People with HIV have a higher risk of myocardial infarction (MI) than the general population, with a greater proportion of type 2 MI (T2MI) due to oxygen demand-supply mismatch compared with type 1 (T1MI) resulting from atherothrombotic plaque disruption. People living with HIV report a greater prevalence of cigarette and alcohol use than do the general population. Alcohol use and smoking as risk factors for MI by type are not well studied among people living with HIV. We examined longitudinal associations between smoking and alcohol use patterns and MI by type among people living with HIV.

DESIGN AND METHODS

Using longitudinal data from the Centers for AIDS Research Network of Integrated Clinical Systems cohort, we conducted time-updated Cox proportional hazards models to determine the impact of smoking and alcohol consumption on adjudicated T1MI and T2MI.

RESULTS

Among 13 506 people living with HIV, with a median 4 years of follow-up, we observed 177 T1MI and 141 T2MI. Current smoking was associated with a 60% increase in risk of both T1MI and T2MI. In addition, every cigarette smoked per day was associated with a 4% increase in risk of T1MI, with a suggestive, but not significant, 2% increase for T2MI. Cigarette use had a greater impact on T1MI for men than for women and on T2MI for women than for men. Increasing alcohol use was associated with a lower risk of T1MI but not T2MI. Frequency of heavy episodic alcohol use was not associated with MI.

CONCLUSIONS

Our findings reinforce the prioritization of smoking reduction, even without cessation, and cessation among people living with HIV for MI prevention and highlight the different impacts on MI type by gender.

Potential Biomarkers to Distinguish Type 1 Myocardial Infarction in Troponin-Elevated Diseases

Classifying myocardial infarction by subtype is crucial for appropriate patient management. Although troponin is currently the most commonly used biomarker, it is not a specific marker for myocardial infarction and cannot distinguish subtypes. Furthermore, previous studies have confirmed that proteins known as myocardial infarction markers could function to distinguish the type of myocardial infarction. Therefore, we identify a marker that can distinguish type 1 myocardial infarction from other diseases with elevated troponin. We used mass spectrometry to compare type 1 myocardial infarction with other conditions characterized by troponin elevation and identified new candidate markers for disease classification. We then verified these markers, along with those already known to be associated with cardiovascular disease and plaque rupture. We identified α-1 acid glycoprotein 2, corticosteroid-binding globulin, and serotransferrin as potential distinguishing markers. The presence of these markers and other parameters, such as chest pain, electrocardiogram, and troponin levels from the complementary diagnostic processes, could provide valuable information to specifically diagnose type 1 myocardial infarction.

A Case of Myocardial Infarction in a Patient With Spontaneous Spinal Subdural Hematoma

Spontaneous spinal subdural hematoma (SSDH) is an extremely rare clinical condition and a neurologic emergency that is most commonly associated with anticoagulation therapy and coagulopathy. We present a case of myocardial infarction (MI) with an unusually high troponin level in the setting of SSDH. This case underscores the challenges and importance of properly differentiating type 1 MI from type 2 MI as the management is different. It also presents challenges in managing MI in the setting of recent bleeding in the context of desired anticoagulation and antiplatelet therapy.

Comparison of outcome among type 2 vs type 1 myocardial infarction: a systematic review and meta-analysis

To date, there were limited studies available on myocardial infarction (MI), and consequently, the outcomes of patients with type 1 myocardial infarction (T1MI) compared to type 2 myocardial infarction (T2MI) remained inconclusive. We aimed to compare the outcomes of T1MI and T2MI patients in terms of mortality and adverse cardiovascular outcomes. We performed a systematic literature search on PubMed, Embase, and Scopus for relevant articles from inception until March 20, 2022. 341,049 patients had T1MI, while the remaining 67,537 patients had T2MI. Mean age was similar between both groups (T1MI: 67.3 years, T2MI: 71.03 years), while the proportion of females was lower in T1MI (37.81% vs 47.15%). Our analysis revealed that patients with T1MI had significantly lower odds of all-cause mortality (OR 0.45, 95% CI 0.36-0.56, p < 0.001), in-hospital mortality (OR 0.63, 95% CI 0.46-0.86, p < 0.001), 1-year mortality (OR 0.35, 95% CI 0.25-0.47, p < 0.001), and major adverse cardiovascular events (MACE) (OR 0.59, 95% CI 0.39-0.91, p = 0.02). There was no significant difference in terms of 30-day mortality (OR 0.58, 95% CI 0.25-1.36, p = 0.21), cardiovascular mortality (OR 0.95, 95% CI 0.68-1.32, p = 0.74), all-cause readmission (OR 0.84, 95% CI 0.62-1.14, p = 0.26), and readmission due to MI (OR 1.22, 95% CI 0.66-2.27, p = 0.53) between both groups. Patients with T1MI had favorable outcomes in terms of mortality and MACE compared to that of T2MI patients. Further studies should aim at determining the optimal management strategy for these high-risk patients for better patient outcomes.

Clinical Characteristics, Outcomes, and Epidemiological Trends of Patients Admitted With Type 2 Myocardial Infarction

Background

Type 2 myocardial infarction (T2MI) was first established as a unique entity in 2007. However, its clinical features are not well characterized. This study aimed to determine the clinical characteristics, predictors of mortality, and hospitalization trends of patients with T2MI.

Methods

The National Inpatient Sample database was queried for patients hospitalized in the United States with T2MI (January 2018 to December 2019). Data were used to assess baseline characteristics, primary diagnoses, predictors of mortality, and hospitalization and mortality trends of T2MI.

Results

During the 24-month study period, 1,789,485 (76%) patients were admitted with type 1 myocardial infarction (T1MI) and 563,695 (24%) were admitted with T2MI. Patients with T2MI were more likely to be older (71 vs 68 years; P < .001) and female (47.5% vs 38.3%; P < .001), with fewer comorbidities related to coronary atherosclerosis. African Americans were the only race with a significantly higher rate of hospitalization for T2MI (15.9% vs 11.6%; P < .001). The predictors of mortality were similar in both the T2MI and T1MI cohorts. Sepsis (23.47%), hypertensive heart disease (15.35%), and atrial arrhythmias (4.49%) were the most common principal diagnoses for T2MI. T2MI hospitalizations trended consistently upward during the study period. Monthly in-hospital mortality rates were consistently higher for T2MI versus T1MI (P < .001).

Conclusions

T2MI is a unique and heterogeneous clinical entity. Despite increased awareness, there is a lack of standardization of medical management and timing for revascularization, even as mortality rates remain persistently elevated compared with T1MI. Certain demographics, including African Americans, may be disproportionately affected.

Outcomes and Resource Utilization in Patients Hospitalized with Gastrointestinal Bleeding Complicated by Types 1 and 2 Myocardial Infarction

BACKGROUND

Types 1 and 2 myocardial infarction (MI) may occur in the setting of gastrointestinal bleeding (GIB). There is a paucity of data pertinent to the contemporary prevalence and impact of types 1 and 2 MI following GIB. We examined clinical profiles and the prognostic impact of both MI types on outcomes of patients hospitalized with GIB.

METHODS

The 2018 Nationwide Readmission Database was queried for patients hospitalized for the primary diagnosis of GIB and had concomitant diagnoses of type 1 or type 2 MI. Baseline characteristics, in-hospital mortality, resource utilization, and 30-day all-cause readmissions were compared among groups.

RESULTS

Of 381,867 primary GIB hospitalizations, 2902 (0.75%) had type 1 MI and 3963 (1.0%) had type 2 MI. GIB patients with type 1 and type 2 MI had significantly higher in-hospital mortality compared to their counterparts without MI (adjusted odds ratios [aOR]: 4.72, 95% confidence interval [CI] 3.43-6.48; and aOR: 2.17, 95% CI 1.48-3.16, respectively). Both types 1 and 2 MI were associated with higher rates of discharge to a nursing facility (aOR of type 1 vs. no MI: 1.65, 95% CI 1.45-1.89, and aOR of type 2 vs no MI: 1.37, 95% CI 1.22-1.54), longer length of stay, higher hospital costs, and more 30-day all-cause readmissions (aOR of type 1 vs no MI: 1.22, 95% CI 1.08-1.38; aOR of type 2 vs no MI: 1.17, 95% CI 1.05-1.30).

CONCLUSION

Types 1 and 2 MI are associated with higher in-hospital mortality and resource utilization among patients hospitalized with GIB in the United States.

Chest pain in patients recovering from noncardiac surgery: A retrospective analysis

STUDY OBJECTIVE

Chest pain is relatively common postoperatively. Myocardial infarction (MI) is one cause of chest pain after surgery, but chest pain also results from less severe conditions. Because of its potential severity, chest pain usually prompts the activation of Rapid Response Systems (RRS). While chest pain is a cardinal symptom of myocardial ischemia in the non-surgical setting, the significance and relevance of chest pain after noncardiac surgery remains unclear.

DESIGN

We conducted a retrospective analysis of noncardiac surgical inpatients for whom postoperative chest pain triggered our multidisciplinary RRS.

SETTING

Surgical wards at Cleveland Clinic, Cleveland, OH.

PATIENTS

Postsurgical patients after noncardiac surgery in whom the RSS system was activated for chest pain.

INTERVENTIONS

RRS specified interventions like ECG readings, troponin measurements, transfer to ICU.

MEASUREMENTS

Our primary outcome was MI. Secondary outcomes included the proportion of patients who had an ECG performed, troponin measurements, echocardiography, cardiac catheterization, and were admitted to the Intensive Care Unit (ICU).

MAIN RESULTS

5850 surgical patients experienced postoperative chest pain and triggered an RRS activation between 2009 and 2019. A total of 3110 patients had troponin T measured within 6 h after RRS activation, and 538 of them (17%) had elevated troponin, meeting the Fourth Universal Definition criteria for MI. Additionally, 2 patients had ST-segment elevation infarction (STEMI) without troponin measurement. Among the 540 patients with MI, only 19 (3.5%) were diagnosed with a STEMI by ECG, 388 (72%) had echocardiography, 43 patients (8%) had cardiac catheterization, 8 patients (1.5%) required emergent cardiac surgery, and 424 (79%) were admitted to an ICU.

CONCLUSION

Chest pain is a serious clinical sign, often indicating a postoperative myocardial infarction, and therefore should be taken seriously. Troponin screening should be routinely considered in postsurgical patients who report chest pain.

Type 2 myocardial infarction: a diagnostic and therapeutic challenge in contemporary cardiology

In the expanding world of cardiovascular diseases, rapidly reaching pandemic proportions, the main focus is still on coronary atherosclerosis and its clinical consequences. However, at least in the Western world, middle-aged male patients with acute myocardial infarction are no more the rule. Due to a higher life expectancy and major medical advances, physicians are to treat older and frailer individuals, usually with multiple comorbidities. In this context, myocardial ischaemia and infarction frequently result from an imbalance between myocardial oxygen supply and demand-i.e., type 2 myocardial infarction (T2MI), according to the current universal definition-rather than coronary atherothrombosis. Moreover, the increasing use of high-sensitivity cardiac troponin assays has led to a heightened detection of T2MI-often causing relatively little myocardial injury-, which seems to have doubled its numbers in recent years. Nevertheless, owing to its multifaceted pathophysiology and clinical presentation, T2MI is still underdiagnosed. Perhaps more importantly, T2MI is also victim of undertreatment, as drugs that constitute the cornerstone of therapy in most cardiovascular diseases are much more unlikely to be prescribed in T2MI than in coronary atherothrombosis. In this paper, we review the recent literature on the classification, pathophysiology, epidemiology, and management of T2MI, trying to summarise the state-of-the-art knowledge about this increasingly important pathologic condition. Finally, based on the current scientific evidence, we also propose an algorithm that may be easily utilised in clinical practice, in order to improve T2MI diagnosis and risk stratification.

Diagnostic features, management and prognosis of type 2 myocardial infarction compared to type 1 myocardial infarction: a systematic review and meta-analysis

IMPORTANCE

Distinguishing type 2 (T2MI) from type 1 myocardial infarction (T1MI) in clinical practice can be difficult, and the management and prognosis for T2MI remain uncertain.

OBJECTIVE

To compare precipitating factors, risk factors, investigations, management and outcomes for T2MI and T1MI.

DATA SOURCES

Medline and Embase databases as well as reference list of recent articles were searched January 2009 to December 2020 for term 'type 2 myocardial infarction'.

STUDY SELECTION

Studies were included if they used a universal definition of MI and reported quantitative data on at least one variable of interest.

DATA EXTRACTION AND SYNTHESIS

Data were pooled using random-effect meta-analysis. Risk of bias was assessed using Newcastle-Ottawa quality assessment tool. Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines were followed. All review stages were conducted by two reviewers.

MAIN OUTCOMES AND MEASURES

Risk factors, presenting symptoms, cardiac investigations such as troponin and angiogram, management and outcomes such as mortality.

RESULTS

40 cohort studies comprising 98 930 patients with T1MI and 13 803 patients with T2MI were included. Compared with T1MI, patients with T2MI were: more likely to have pre-existing chronic kidney disease (OR 1.87; 95% CI 1.53 to 2.28) and chronic heart failure (OR 2.35; 95% CI 1.82 to 3.03), less likely to present with typical cardiac symptoms of chest pain (OR 0.19; 95% CI 0.13 to 0.26) and more likely to present with dyspnoea (OR 2.64; 95% CI 1.86 to 3.74); more likely to demonstrate non-specific ST-T wave changes on ECG (OR 2.62; 95% CI 1.81 to 3.79) and less likely to show ST elevation (OR 0.22; 95% CI 0.17 to 0.28); less likely to undergo coronary angiography (OR 0.09; 95% CI 0.06 to 0.12) and percutaneous coronary intervention (OR 0.06; 95% CI 0.04 to 0.10) or receive cardioprotective medications, such as statins (OR 0.25; 95% CI 0.16 to 0.38) and beta-blockers (OR 0.45; 95% CI 0.33 to 0.63). T2MI had greater risk of all cause 1-year mortality (OR 3.11; 95% CI 1.91 to 5.08), with no differences in short-term mortality (OR 1.34; 95% CI 0.63 to 2.85).

CONCLUSION AND RELEVANCE

This review has identified clinical, management and survival differences between T2MI and T1MI with greater precision and scope than previously reported. Differential use of coronary revascularisation and cardioprotective medications highlight ongoing uncertainty of their utility in T2MI compared with T1MI.

Myocardial infarction during giant cell arteritis: A cohort study

BACKGROUND

Cardiovascular risk is increased in giant cell arteritis (GCA). We aimed to characterize myocardial infarction (MI) in a GCA cohort, and to compare the GCA and non-GCA population affected by MI.

METHODS

In patients with a biopsy-proven diagnosis of GCA between 1 January 2001 and 31 December 2016 in Côte D'Or (France), we identified patients with MI by crossing data from the territorial myocardial infarction registry (Observatoire des Infarctus de Côte d'Or) database. Five controls (non-GCA + MI) were paired with one case (GCA + MI) after matching for age, sex, cardiovascular risk factors and prior cardiovascular disease. MI were characterized as type 1 MI (T1MI), resulting from thrombus formation due to atherothrombotic disease, or type 2 MI (T2MI), due to a myocardial supply/demand mismatch. GCA-related MI was defined as MI occurring within 3 months of a GCA flare (before or after).

RESULTS

Among 251 biopsy-proven GCA patients, 13 MI cases were identified and paired with 65 controls. MI was GCA-related in 6/13 cases, accounting for 2.4% (6/251) of our cohort. T2MI was more frequently GCA-related than GCA-unrelated (80% vs. 16.7%, p = 0.080), and GCA diagnosis was the only identified triggering factor in 75% of GCA-related T2MI. GCA-unrelated MI were more frequently T1MI and occurred in patients who had received a higher cumulative dose of prednisone (p = 0.032). GCA was not associated with poorer one-year survival.

CONCLUSIONS

GCA-related MI are mainly T2MI probably caused by systemic inflammation rather than coronaritis. GCA-unrelated MI are predominantly T1MI associated with atherothrombotic coronary artery disease.

Impact of myocardial infarction symptom presentation on emergency response and survival

AIMS

We examined associations between symptom presentation and chance of receiving an emergency dispatch and 30-day mortality among patients with acute myocardial infarction (MI).

METHODS AND RESULTS

Copenhagen, Denmark has a 24-h non-emergency medical helpline and an emergency number 1-1-2 (equivalent to 9-1-1). Both services register symptoms/purpose of calls. Among patients with MI as either hospital diagnosis or cause of death within 72 h after a call, the primary symptom was categorized as chest pain, atypical symptoms (breathing problems, unclear problem, central nervous system symptoms, abdominal/back/urinary, other cardiac symptoms, and other atypical symptoms), unconsciousness, non-informative symptoms, and no recorded symptoms. We identified 4880 emergency and 3456 non-emergency calls from patients with MI. The most common symptom was chest pain (N = 5219) followed by breathing problems (N = 556). Among patients with chest pain, 95% (3337/3508) of emergency calls and 76% (1306/1711) of non-emergency calls received emergency dispatch. Mortality was 5% (163/3508) and 3% (49/1711) for emergency/non-emergency calls, respectively. For atypical symptoms 62% (554/900) and 17% (137/813) of emergency/non-emergency calls received emergency dispatch and mortality was 23% (206/900) and 15% (125/813). Among unconscious, patients 99%/100% received emergency dispatch and mortality was 71%/75% for emergency/non-emergency calls. Standardized 30-day mortality was 4.3% for chest pain and 15.6% for atypical symptoms, and associations between symptoms and emergency dispatch remained in subgroups of age and sex.

CONCLUSION

Myocardial infarction patients presenting with atypical symptoms when calling for help have a reduced chance of receiving an emergency dispatch and increased 30-day mortality compared to MI patients with chest pain.

Revascularization rates with coronary angioplasty and mortality in type 2 myocardial infarction: A meta-regression analysis

BACKGROUND

Percutaneous coronary intervention (PCI) represents the best therapeutic option for type-1 myocardial infarction (T1MI) in the majority of clinical settings; its role in the treatment of type-2 myocardial infarction (T2MI), however, remains unclear. We therefore sought to assess in a meta-regression analysis the impact of PCI rates on mortality in patients with T2MI according to available observational studies.

METHODS

We performed a meta-regression analysis including all the studies involving in-patients affected by T2MI. We excluded studies not reporting the rate of T2MI patients undergoing PCI and not specifying absolute in-hospital or 1-year all-cause mortality. In the meta-regression analysis we used the in-hospital mortality and 1-year mortality as dependent variables and the rate of PCI as independent; regression was weighted for studies' size.

RESULTS

After careful examination, 8 studies were selected for the assessment of in-hospital mortality and 8 for 1-year-mortality. We included 3155 and 3756 in-patients for in-hospital and 1-year mortality respectively. At meta-regression analysis, a borderline correlation between PCI rate and in-hospital mortality (p 0.05) and a statistically significant correlation with 1-year mortality (p < 0.01) in T2MI patients were found.

CONCLUSIONS

In a meta-regression analysis higher rates of PCI on T2MI in-patients were associated with lower mortality rates both in-hospital and at 1 year. Whether this association is related to the direct effect of PCI or better general conditions of T2MI patients undergoing a PCI still remains unclear.

Paraoxonase 1 concerning dyslipidaemia, cardiovascular diseases, and mortality in haemodialysis patients

Paraoxonase 1 (PON1) is known for preventing atherosclerosis through lipid-modifying features, antioxidant activity, anti-inflammatory, anti-apoptosis, anti-thrombosis, and anti-adhesion properties. Uremic patients requiring haemodialysis (HD) are especially prone to atherosclerosis and its complications. We analysed the PON1 gene (PON1) polymorphisms and serum PON1 (paraoxonase) activity concerning dyslipidaemia and related cardiovascular diseases and mortality to show how they associate under uremic conditions modified by maintenance HD treatment. The rs662 AA + AG (OR 1.76, 95%CI 1.10-2.80, P = 0.018), rs854560 TT (OR 1.48, 95%CI 1.04-2.11, P = 0.031), and rs854560 AT + TT (OR 1.28, 95%CI 1.01-1.63, P = 0.040) contributed to the prevalence of atherogenic dyslipidaemia diagnosed by the triglyceride (TG)/HDL-cholesterol ratio ≥ 3.8. The normalized serum PON1 activity positively correlated with atherogenic dyslipidaemia (ẞ 0.67 ± 0.25, P = 0.008). The PON1 rs854560 allele T was involved in the higher prevalence of ischemic cerebral stroke (OR 1.38, 1.02-1.85, P = 0.034). The PON1 rs705379 TT genotype contributed to cardiovascular (HR 1.27, 95% CI 1.03-1.57, P = 0.025) and cardiac (HR 1.34, 95% CI 1.05-1.71, P = 0.018) mortality. All P-values were obtained in multiple regression analyses, including clinical variables. Multifaceted associations of PON1 with dyslipidaemia, ischemic cerebral stroke, and cardiovascular mortality in HD patients provide arguments for the consideration of PON1 and its protein product as therapeutic targets in the prevention of atherosclerosis and its complications in uremic patients.

Troponin elevation pattern and subsequent cardiac and non-cardiac outcomes: Implementing the Fourth Universal Definition of Myocardial Infarction and high-sensitivity troponin at a population level

Background

The Fourth Universal Definition of Myocardial Infarction (MI) differentiates MI from myocardial injury. We characterised the temporal course of cardiac and non-cardiac outcomes associated with MI, acute and chronic myocardial injury.

Methods

We included all patients presenting to public emergency departments in South Australia between June 2011–Sept 2019. Episodes of care (EOCs) were classified into 5 groups based on high-sensitivity troponin-T (hs-cTnT) and diagnostic codes: 1) Acute MI [rise/fall in hs-cTnT and primary diagnosis of acute coronary syndrome], 2) Acute myocardial injury with coronary artery disease (CAD) [rise/fall in hs-cTnT and diagnosis of CAD], 3) Acute myocardial injury without CAD [rise/fall in hs-cTnT without diagnosis of CAD], 4) Chronic myocardial injury [elevated hs-cTnT without rise/fall], and 5) No myocardial injury. Multivariable flexible parametric models were used to characterize the temporal hazard of death, MI, heart failure (HF), and ventricular arrhythmia.

Results

372,310 EOCs (218,878 individuals) were included: acute MI (19,052 [5.12%]), acute myocardial injury with CAD (6,928 [1.86%]), acute myocardial injury without CAD (32,231 [8.66%]), chronic myocardial injury (55,056 [14.79%]), and no myocardial injury (259,043 [69.58%]). We observed an early hazard of MI and HF after acute MI and acute myocardial injury with CAD. In contrast, subsequent MI risk was lower and more constant in patients with acute injury without CAD or chronic injury. All patterns of myocardial injury were associated with significantly higher risk of all-cause mortality and ventricular arrhythmia.

Conclusions

Different patterns of myocardial injury were associated with divergent profiles of subsequent cardiac and non-cardiac risk. The therapeutic approach and modifiability of such excess risks require further research.

Associations of Serum Nonesterified Fatty Acids With Coronary Heart Disease Mortality and Nonfatal Myocardial Infarction: The CHS (Cardiovascular Health Study) Cohort

Background

Significant associations have been reported between serum total nonesterified fatty acid (NEFA) concentrations and coronary heart disease (CHD) mortality and incident nonfatal myocardial infarction (MI) in some prospective cohort studies. Little is known about whether individual or subclasses (saturated, polyunsaturated [n‐6 and n‐3], and trans fatty acids) of serum NEFAs relate to CHD mortality and nonfatal MI.

Methods and Results

CHS (Cardiovascular Health Study) participants (N=1681) who had no history of MI, angina, or revascularization or were free of MI at baseline (1996–1997) were included. NEFAs were quantified using gas chromatography. Cox regression analysis was used to evaluate associations of 5 subclasses and individual NEFAs with CHD composite (CHD mortality and nonfatal MI), CHD mortality, and incident nonfatal MI. During a median follow‐up of 11.7 years, 266 cases of CHD death and 271 cases of nonfatal MI occurred. In the fully adjusted model, no significant associations were identified between individual NEFA and CHD composite. Exploratory analyses indicated that lauric acid (12:0) was negatively associated (hazard ratio [HR], 0.76; 95% CI, 0.59–0.98; P=0.0328) and dihomo‐γ‐linolenic acid (20:3n‐6) was positively associated with CHD mortality (HR, 1.34; 95% CI, 1.02–1.76; P=0.0351). Elaidic acid (18:1n‐7t) was positively associated with incident nonfatal MI (HR, 1.46; 95% CI, 1.01–2.12; P=0.0445). No significant associations were observed for NEFA subclass and any outcomes.

Conclusions

In CHS participants, 2 NEFAs, dihomo‐γ‐linolenic and elaidic acids, were positively associated with CHD mortality and nonfatal MI, respectively, suggesting potential susceptibility biomarkers for risks of CHD mortality and nonfatal MI.

Cross-Priming Dendritic Cells Exacerbate Immunopathology After Ischemic Tissue Damage in the Heart

BACKGROUND

Ischemic heart disease is a leading cause of heart failure and despite advanced therapeutic options, morbidity and mortality rates remain high. Although acute inflammation in response to myocardial cell death has been extensively studied, subsequent adaptive immune activity and anti-heart autoimmunity may also contribute to the development of heart failure. After ischemic injury to the myocardium, dendritic cells (DC) respond to cardiomyocyte necrosis, present cardiac antigen to T cells, and potentially initiate a persistent autoimmune response against the heart. Cross-priming DC have the ability to activate both CD4+ helper and CD8+ cytotoxic T cells in response to necrotic cells and may thus be crucial players in exacerbating autoimmunity targeting the heart. This study investigates a role for cross-priming DC in post-myocardial infarction immunopathology through presentation of self-antigen from necrotic cardiac cells to cytotoxic CD8+ T cells.

METHODS

We induced type 2 myocardial infarction-like ischemic injury in the heart by treatment with a single high dose of the β-adrenergic agonist isoproterenol. We characterized the DC population in the heart and mediastinal lymph nodes and analyzed long-term cardiac immunopathology and functional decline in wild type and Clec9a-depleted mice lacking DC cross-priming function.

RESULTS

A diverse DC population, including cross-priming DC, is present in the heart and activated after ischemic injury. Clec9a-/- mice deficient in DC cross-priming are protected from persistent immune-mediated myocardial damage and decline of cardiac function, likely because of dampened activation of cytotoxic CD8+ T cells.

CONCLUSION

Activation of cytotoxic CD8+ T cells by cross-priming DC contributes to exacerbation of postischemic inflammatory damage of the myocardium and corresponding decline in cardiac function. Importantly, this provides novel therapeutic targets to prevent postischemic immunopathology and heart failure.

Discordance between the Clinical Presentation and Morphology of Myocardial Infarction in a Patient with Acute Post-Hemorrhagic Anemia

While atherosclerotic plaque disruption remains the hallmark of type 1 myocardial infarction (T1MI), multiple other mechanisms provoking myocardial supply/demand mismatch (eg, anemia and tachyarrhythmias) are recognized as the potential causes of type 2 myocardial infarction (T2MI). In clinical practice, angiography is underutilized in patients with MI that have typical T2MI triggers, although the presence of these triggers and various forms of atherosclerotic coronary artery disease is not mutually exclusive. We describe a 70-year-old man that developed MI during hospitalization for gastrointestinal bleeding. He was treated conservatively without angiography due to posthemorrhagic anemia, which is a recognized T2MI trigger, and subsequently developed refractory cardiogenic shock. Autopsy revealed atherothrombosis, which is characteristic of T1MI.

Brief Report: Differences in Types of Myocardial Infarctions Among People Aging With HIV

BACKGROUND

Type 1 myocardial infarctions (T1MIs) result from atherosclerotic plaque instability, rupture, and/or erosion. Type 2 MIs (T2MIs) are secondary to causes such as sepsis and cocaine-induced vasospasm resulting in an oxygen demand-supply mismatch and are associated with higher mortality than T1MIs. T2MIs account for a higher proportion of MIs among people living with HIV (PLWH) compared with the general population. We compared MI rates by type among aging PLWH. We hypothesized that increases in MI rates with older age would differ by MI types, and T2MIs would be more common than T1MIs in younger individuals.

METHODS

Potential MIs from 6 sites were centrally adjudicated using physician notes, electrocardiograms, procedure results, and laboratory results. Reviewers categorized MIs by type and identified causes of T2MIs. We calculated T1MI and T2MI incidence rates. Incidence rate ratios were calculated for T2MI vs. T1MI rates per decade of age.

RESULTS

We included 462 T1MIs (52%) and 413 T2MIs (48%). T1MI rates increased with older age, although T1MIs occurred in all age decades including young adults. T2MI rates were significantly higher than T1MI rates for PLWH younger than 40 years. T1MI rates were similar or higher than T2MI rates among those older than 40 years (significantly higher for those aged 50-59 and 60-69 years).

CONCLUSIONS

Rates of T2MIs were higher than T1MIs until age 40 years among PLWH, differing from the general population, but rates of both were high among older PLWH. Given prognostic differences between MI types, these results highlight the importance of differentiating MI types among PLWH.

The Multifaceted Interplay between Atrial Fibrillation and Myocardial Infarction: A Review

This review was conducted to emphasize the complex interplay between atrial fibrillation (AF) and myocardial infraction (MI). In type 1 (T1) MI, AF is frequent and associated with excess mortality. Moreover, AF after hospital discharge for T1MI is not rare, suggesting the need to improve AF screening and to develop therapeutic strategies for AF recurrence. Additionally, AF is a common trigger for type 2 MI (T2MI), and recent data have shown that tachyarrhythmia or bradyarrhythmia could be a causal factor in, respectively, 13-47% or 2-7% of T2MI. In addition, AF is involved in T2MI pathogenesis as a result of severe anemia related to anticoagulants. AF is also an underestimated and frequent cause of coronary artery embolism (CE), as a situation at risk of myocardial infarction with non-obstructive coronary arteries. AF-causing CE is difficult to diagnose and requires specific management. Moreover, patients with both AF and chronic coronary syndromes represent a therapeutic challenge because the treatment of AF include anticoagulation, depending on the embolic risk, and ischemic heart disease management paradoxically includes antiplatelet therapy.

Type 2 MI induced by a single high dose of isoproterenol in C57BL/6J mice triggers a persistent adaptive immune response against the heart

Heart failure is the common final pathway of several cardiovascular conditions and a major cause of morbidity and mortality worldwide. Aberrant activation of the adaptive immune system in response to myocardial necrosis has recently been implicated in the development of heart failure. The ß-adrenergic agonist isoproterenol hydrochloride is used for its cardiac effects in a variety of different dosing regimens with high doses causing acute cardiomyocyte necrosis. To assess whether isoproterenol-induced cardiomyocyte necrosis triggers an adaptive immune response against the heart, we treated C57BL/6J mice with a single intraperitoneal injection of isoproterenol. We confirmed tissue damage reminiscent of human type 2 myocardial infarction. This is followed by an adaptive immune response targeting the heart as demonstrated by the activation of T cells, the presence of anti-heart auto-antibodies in the serum as late as 12 weeks after initial challenge and IgG deposition in the myocardium. All of these are hallmark signs of an established autoimmune response. Adoptive transfer of splenocytes from isoproterenol-treated mice induces left ventricular dilation and impairs cardiac function in healthy recipients. In summary, a single administration of a high dose of isoproterenol is a suitable high-throughput model for future studies of the pathological mechanisms of anti-heart autoimmunity and to test potential immunomodulatory therapeutic approaches.

Myocardial Infarction Type 2: Avoiding Pitfalls and Preventing Adverse Outcomes

Myocardial infarction type 2 (MI type 2) is an elevation of cardiac biomarkers in a physiologically stressful state leading to demand-supply mismatch of oxygen. This type of myocardial infarction is commonly seen in hospitalized patients. Since the introduction of clear definition, diagnostic criteria and International Classification of Disease (ICD) codes, the diagnosis has become increasingly common. There still remains plenty to learn about MI type 2 especially prevention and treatment strategies. Studies have shown that there is increased mortality and morbidity associated with MI type 2 when compared to MI type 1, and there may be benefit in having a multi-disciplinary approach including cardiology when treating such patients. Secondary prevention therapies may also play a role in decreasing adverse events from MI type 2. However, randomized control trials are insufficient, and results of studies are cautiously interpreted. In this article we have assessed the current evidence on MI type 2 and the gap in literature that will potentially be the focus of future analyses.

State of the Art-High-Sensitivity Troponins in Acute Coronary Syndromes

In cases of suspected acute coronary syndrome (ACS), rapid and accurate diagnosis is essential to establish effective evidence-based medical treatment. Patients' history, clinical examination, 12-lead electrocardiogram, and cardiac biomarkers are cornerstones in initial management. Since high-sensitivity cardiac troponins were established, they have markedly expedited and revolutionized rule-in and rule-out pathways of patients with ACS and changed our everyday clinical practice. Thus, they have become an indispensable tool in daily routine in emergency units. This review focuses on historical and contemporary standards in laboratory biomarkers of myocardial injury and discusses their implication in the context of the updated universal definition of myocardial infarction.

Oral Antiplatelet Therapy Administered Upstream to Patients With NSTEMI

To describe from a noninterventional registry (Utilization of Ticagrelor in the Upstream Setting for Non-ST-Segment Elevation Acute Coronary Syndrome), the short-term ischemic and hemorrhagic outcomes in patients with non-ST elevation myocardial infarction (MI) are managed with a loading dose (LD) of a P2Y₁₂ inhibitor (P2Y₁₂i) given at least 4 hours before diagnostic angiography and delineation of coronary anatomy. Prior data on the effects of such “upstream loading” have been inconsistent.

Cardiorespiratory Fitness and the Risk of First Acute Myocardial Infarction: The HUNT Study

Background

The majority of studies evaluating cardiorespiratory fitness (CRF) as a cardiovascular risk factor use cardiovascular mortality and not cardiovascular disease events as the primary end point, and generally do not include women. The aim of this study was to investigate the association of estimated CRF (eCRF) with the risk of first acute myocardial infarction (AMI).

Methods and Results

We included 26 163 participants (51.5% women) from the HUNT study (Nord‐Trøndelag Health Study), with a mean age of 55.7 years, without cardiovascular disease at baseline. Baseline eCRF was grouped into tertiles. AMI was derived from hospital records and deaths from the Norwegian Cause of Death Registry. We used Fine and Gray regression modeling to estimate subdistribution hazards ratio (SHR) of AMI, accounting for competing risk of death. During a mean (range) follow‐up of 13 (0.02–15.40) years (347 462 person‐years), 1566 AMI events were recorded. In fully adjusted models men in the 2 highest eCRF had 4% (SHR: 0.96, 95% CI: 0.83–1.11) and 10% (SHR: 0.90, 95% CI: 0.77–1.05) lower SHR of AMI, respectively, when compared with men in the lowest tertile. The corresponding numbers in women were 12% (SHR: 0.88, 95% CI: 0.72–1.08) and 25% (SHR: 0.75, 95% CI: 0.60–0.95).

Conclusions

eCRF was inversely associated with risk of AMI event among women but not in men. Our data suggest that high eCRF may have substantial benefit in reducing the risk of AMI. Therefore, our data suggest that an increased focus on eCRF as a cardiovascular disease risk marker in middle‐aged and older adults is warranted.

Accuracy of Physicians in Differentiating Type 1 and Type 2 Myocardial Infarction Based on Clinical Information

Background

Physicians commonly judge whether a myocardial infarction (MI) is type 1 (thrombotic) vs type 2 (supply/demand mismatch) based on clinical information. Little is known about the accuracy of physicians’ clinical judgement in this regard. We aimed to determine the accuracy of physicians’ judgement in the classification of type 1 vs type 2 MI in perioperative and nonoperative settings.

Methods

We performed an online survey using cases from the Optical Coherence Tomographic Imaging of Thrombus (OPTIMUS) Study, which investigated the prevalence of a culprit lesion thrombus based on intracoronary optical coherence tomography (OCT) in patients experiencing MI. Four MI cases, 2 perioperative and 2 nonoperative, were selected randomly, stratified by etiology. Physicians were provided with the patient’s medical history, laboratory parameters, and electrocardiograms. Physicians did not have access to intracoronary OCT results. The primary outcome was the accuracy of physicians' judgement of MI etiology, measured as raw agreement between physicians and intracoronary OCT findings. Fleiss’ kappa and Gwet’s AC1 were calculated to correct for chance.

Results

The response rate was 57% (308 of 536). Respondents were 62% male; median age was 45 years (standard deviation ± 11); 45% had been in practice for > 15 years. Respondents’ overall accuracy for MI etiology was 60% (95% confidence interval [CI] 57%-63%), including 63% (95% CI 60%-68%) for nonoperative cases, and 56% (95% CI 52%-60%) for perioperative cases. Overall chance-corrected agreement was poor (kappa = 0.05), consistent across specialties and clinical scenarios.

Conclusions

Physician accuracy in determining MI etiology based on clinical information is poor. Physicians should consider results from other testing, such as invasive coronary angiography, when determining MI etiology.

Epidemiology of Atrial Fibrillation in the 21st Century: Novel Methods and New Insights

Accompanying the aging of populations worldwide, and increased survival with chronic diseases, the incidence and prevalence of atrial fibrillation (AF) are rising, justifying the term global epidemic. This multifactorial arrhythmia is intertwined with common concomitant cardiovascular diseases, which share classical cardiovascular risk factors. Targeted prevention programs are largely missing. Prevention needs to start at an early age with primordial interventions at the population level. The public health dimension of AF motivates research in modifiable AF risk factors and improved precision in AF prediction and management. In this review, we summarize current knowledge in an attempt to untangle these multifaceted associations from an epidemiological perspective. We discuss disease trends, preventive opportunities offered by underlying risk factors and concomitant disorders, current developments in diagnosis and risk prediction, and prognostic implications of AF and its complications. Finally, we review current technological (eg, eHealth) and methodological (artificial intelligence) advances and their relevance for future prevention and disease management.

Acute Coronary Syndrome with Non-ruptured Plaques (NONRUPLA): Novel Ideas and Perspectives

PURPOSE OF REVIEW

In this review article, we focus on the mechanisms and features of acute coronary syndromes (ACS) with no ruptured plaque (NONRUPLA) highlighting the uncertainties over diagnostic evaluation and treatment.

RECENT FINDINGS

The most common cause of ACS is obstruction due to atherosclerotic plaque ruptured or erosion. In 14% of patients who present in the Emergency Department as myocardial infarction, the final diagnosis is ACS with NONRUPLA. Although the clinical presentation of NONRUPLA may mimic myocardial infarction, the underlying pathogenesis is different, and it may guide therapeutic approaches and overall prognosis that vary according to etiology. The possible mechanisms of ACS with NONRUPLA are coronary embolism, acute dissection of the aorta or coronary artery, vasospasm, microvascular dysfunction, the imbalance between oxygen demand and supply, coronary trauma and stent complications, direct cellular toxicity and damage, Takotsubo syndrome, and myocardial infarction with non-obstructive coronary arteries (MINOCA).

Adjudication of cardiovascular events in patients with chronic obstructive pulmonary disease: SUMMIT trial

Background:

Adjudicated cause-specific mortality has been used in major trials of chronic obstructive pulmonary disease. However, there is less experience with adjudicated major adverse cardiovascular events as a key efficacy outcome in chronic obstructive pulmonary disease trials. The Study to Understand Mortality and Morbidity in chronic obstructive pulmonary disease trial required a Clinical Endpoint Committee to adjudicate the outcomes of modified major adverse cardiovascular events and cause-specific mortality.

Methods and results:

A six-member Clinical Endpoint Committee reviewed adverse event and serious adverse event reports included in a list of 204 Medical Dictionary for Regulatory Activities terms. Adverse events were triaged by one Clinical Endpoint Committee member, and then reviewed by three reviewers (round 1). If these three disagreed on the adjudication, the event was discussed by the full committee to reach a consensus (round 2). Among 16,485 participants, 48,105 adverse events were reported, among which 3314 were reviewed by the Clinical Endpoint Committee. After triage, 1827 were adjudicated in round 1; 338 required committee consensus in round 2, yielding 450 myocardial infarctions, strokes, unstable anginas or transient ischaemic attacks. Only 20/1627 (1%) non-serious adverse events were adjudicated as cardiovascular events. Only 45/204 Medical Dictionary for Regulatory Activities terms reviewed yielded cardiovascular events. A total of 430 deaths were adjudicated in round 1 and 631 in round 2, yielding 459 cardiovascular deaths. Adjudication of chest pain and sudden death often required additional information from site investigators. Site assessment of cardiovascular death was moderately specific (501/602 = 83%) but not sensitive (256/459 = 56%).

Conclusion:

A Clinical Endpoint Committee is useful for adjudication of major adverse cardiovascular events in chronic obstructive pulmonary disease trials but requires considerable resources and effort by investigators. This process can be streamlined by reviewing only serious adverse events and filtering by selected Medical Dictionary for Regulatory Activities terms.

Meta-analysis Comparing Outcomes of Type 2 Myocardial Infarction and Type 1 Myocardial Infarction With a Focus on Dual Antiplatelet Therapy

BACKGROUND

There are important knowledge gaps in type 2 myocardial infarction (T2MI). Our primary objective was to compare the outcomes of patients with T2MI with those of patients with type 1 myocardial infarction (T1MI). Our secondary objective was to determine whether randomized controlled trials (RCTs) evaluating dual antiplatelets (DAPTs) have explicitly included patients with T2MI.

METHODS

We performed a meta-analysis comparing outcomes of patients with T2MI with patients with T1MI and a separate systematic review to evaluate the inclusion of T2MI in RCTs evaluating DAPT. There were 19 cohorts enrolling 48,829 patients (40,604 with T1MI and 5361 with T2MI) and 51 RCTs enrolling 188,132 patients with acute coronary syndrome.

RESULTS

Patients with T2MI had approximately 2-fold increases in unadjusted odds of long-term mortality compared with patients with T1MI (odds ratio, 2.47; 95% confidence interval, 2.06-2.96; P < 0.0001) and a 45% increase in adjusted odds of long-term mortality (odds ratio, 1.45; 95% confidence interval, 1.25-1.69; P < 0.0001, respectively). There was no published evaluation of efficacy, effectiveness, and safety of DAPT in patients with T2MI.

CONCLUSION

Patients with T2MI are at increased risk of adjusted all-cause long-term mortality compared with patients with T1MI. The role of DAPT remains unclear in T2MI.

Defining and managing patients with non-ST-elevation myocardial infarction: Sorting through type 1 vs other types

Advances in cardiovascular (CV) imaging, redefined electrocardiogram criteria, and high-sensitivity CV biomarker assays have enabled more differentiated etiological classification of myocardial infarction (MI). Type 1 MI has a different underlying pathophysiology than type 2 through type 5 MI; type 1 MI is characterized primarily by intracoronary atherothrombosis and the other types by a variety of mechanisms, which can occur with or without an atherosclerotic component. In type 2 MI, there is evidence of myocardial oxygen supply-demand imbalance unrelated to acute coronary atherothrombosis. Types 1 and 2 MI are spontaneous events, while type 4 and type 5 are procedure-related; type 3 MI is identified only after death. Most type 1 and type 2 MI present as non-ST-elevation MI (NSTEMI), although both types can also present as ST-elevation MI. Because of their different underlying etiologies, type 1 and type 2 NSTEMI have different presentation and prognosis and should be managed differently. In this article, we discuss the epidemiology, prognosis, and management of NSTEMI occurring in the setting of underlying type 1 or type 2 pathophysiology. Most NSTEMI (65%-90%) are type 1 MI. Patients with type 2 MI have multiple comorbidities and causes of in-hospital mortality among these patients are not always CV-related. It is important to distinguish between type 1 and type 2 NSTEMI early in the clinical course to allow for the use of the most appropriate treatments that will provide the greatest benefit for these patients.

Incidence, Characteristics, and Outcomes of Myocardial Infarction in Patients With Peripheral Artery Disease: Insights From the EUCLID Trial

Importance

Patients with peripheral artery disease (PAD) are at high risk for myocardial infarction (MI).

Objective

To characterize the incidence and types of MI in a PAD population, identify factors associated with MI, and determine the association of MI with cardiovascular mortality and acute limb ischemia.

Design, Setting, and Participants

The Study Comparing Cardiovascular Effects of Ticagrelor and Clopidogrel in Patients With Peripheral Artery Disease (EUCLID) was a double-blind randomized clinical trial conducted at 811 sites in 28 countries that randomized 13 885 patients with symptomatic PAD to monotherapy with ticagrelor or clopidogrel. Participants had an ankle-brachial index (ABI) of 0.80 or less or previous lower extremity revascularization. Median follow-up was 30 months. For these analyses, patients were evaluated for MI occurrence during follow-up irrespective of treatment. Data were analyzed from June 2017 to September 2018.

Main Outcomes and Measures

An adjudication clinical events committee classified MI as type 1 (spontaneous), type 2 (secondary), type 3 (sudden cardiac death), type 4a (less than 48 hours after percutaneous coronary intervention), type 4b (definite stent thrombosis), or type 5 (less than 72 hours after coronary artery bypass graft). A multivariate regression model was developed by stepwise selection to identify factors associated with MI, and a time-dependent multivariate Cox regression analysis was performed to determine the association of MI with cardiovascular death and acute limb ischemia requiring hospitalization.

Results

Of the 13 885 patients included in this analysis, 9997 (72.0%) were male, and the median (interquartile range) age was 66 (60-73) years. Myocardial infarction occurred in 683 patients (4.9%; 2.4 events per 100 patient-years) during a median follow-up of 30 months. Patients experiencing MI were older (median [interquartile range] age, 69 [62-75] vs 66 [60-72] years), more likely to have diabetes (349 of 683 [51.1%] vs 4996 of 13 202 [37.8%]) or a previous lower extremity revascularization (466 of 683 [68.2%] vs 7409 of 13 202 [56.1%]), and had a lower ABI (if included by ABI) compared with censored patients. Of the 683 patients with MI during follow-up, the most common MI type was type 1 (405 [59.3%]), followed by type 2 (236 [34.6%]), type 4a (14 [2.0%]), type 3 (12 [1.8%]), type 4b (11 [1.6%]), and type 5 (5 [0.7%]). Postrandomization MI was independently associated with cardiovascular death (adjusted hazard ratio, 9.0; 95% CI, 7.3-11.2; P < .001) and acute limb ischemia requiring hospitalization (adjusted hazard ratio, 2.5; 95% CI, 1.3-5.0; P = .008).

Conclusions and Relevance

Approximately 5% of patients with symptomatic PAD had an MI during a median follow-up of 30 months. Type 1 MI (spontaneous) was the most common MI type; however, one-third of MIs were type 2 MI (secondary). More research is needed to identify therapies to reduce the risk of MI in patients with PAD and to improve management of type 2 MI.

Trial Registration

ClinicalTrials.gov Identifier: NCT01732822.

Type 1 or Type 2 Myocardial Infarction in Patients with a History of Coronary Artery Disease: Data from the Emergency Department

A type 2 myocardial infarction (T2MI) is the result of an imbalance between oxygen supply and demand, without acute atherothrombosis. T2MI is frequent in emergency departments (ED), but has not been extensively evaluated in patients with previously known coronary artery disease (CAD). Our study assessed the incidence and characteristics of T2MI compared to type 1 (T1MI) in CAD patients admitted to an ED. Among 33,669 consecutive patients admitted to the ED, 2830 patients with T1MI or T2MI were systematically included after prospective adjudication by the attending clinician according to the universal definition. Among them, 619 (22%) patients had a history of CAD. Using multivariable analysis, CAD history was found to be an independent predictive factor of T2MI versus T1MI (odds ratio (95% confidence interval) = 1.38 (1.08-1.77), p = 0.01). Among CAD patients, those with T2MI (n = 254) were older (median age: 82 vs. 72 years, p < 0.001), and had more frequent comorbidities and more frequent three-vessel disease at the coronary angiography (56% vs. 43%, p = 0.015). Percutaneous coronary intervention was by far less frequent after T2MI than after T1MI (28% vs. 67%, p < 0.001), and in-hospital mortality was twice as high in T2MI (15% vs. 7% for T1MI, p < 0.001). Among biomarkers, the C reactive protein (CRP)/troponin Ic ratio predicted T2MI remarkably well (C-statistic (95% confidence interval) = 0.84 (0.81-0.87, p < 0.001). In a large unselected cohort of MI patients in the ED, a quarter of patients had previous CAD, which was associated with a 40% higher risk of T2MI. CRP/troponin ratios could be used to help distinguish T2MI from T1MI.

Evaluation of a 1-hour troponin algorithm for diagnosing myocardial infarction in high-risk patients admitted to a chest pain unit: the prospective FAST-MI cohort study

OBJECTIVE

This study sought to evaluate the diagnostic performance of the 1-hour troponin algorithm for diagnosis of myocardial infarction (MI) without persistent ST-segment elevations (non-ST-segment MI (NSTEMI)) in a cohort with a high prevalence of MI. This algorithm recommend by current guidelines was previously developed in cohorts with a prevalence of MI of less than 20%.

DESIGN

Prospective cohort study from November 2015 until December 2016.

SETTING

Dedicated chest pain unit of a single referral centre.

PARTICIPANTS

Consecutive patients with suspected MI were screened. Patients with subacute symptoms lasting more than 24 hours, new ST-segment elevations at presentation, or an already diagnosed or ruled-out acute MI were excluded. All enrolled patients (n=1317) underwent a full clinical assessment and measurements of high-sensitivity troponin, and were scheduled for an early invasive strategy if clinically indicated.

MAIN OUTCOME MEASURES

Final diagnosis of MI according to the Fourth Universal Definition of MI.

RESULTS

The prevalence of NSTEMI in the present cohort was 36.9%. The sensitivity for rule-out of MI was 99.8%. The specificity for rule-in of MI was found to be 94.3%. However, in 35.7% of patients neither rule-in nor rule-out was possible. In 51.4% of patients diagnosed with MI, a primary non-coronary reason for MI was found (type 2 MI). Different receiver operating characteristic-curve derived cut-offs for troponin and its dynamics did not provide a sufficient differentiation between type 1 and 2 MI for clinical decision making (negative predictive value for rule-out of type 1 MI <70%).

CONCLUSIONS

The 1-hour diagnosis algorithm for patients with suspected NSTEMI can accurately diagnose acute MI in high-risk cohorts. However, discrimination between patients needing an early invasive strategy or not is limited.

TRIAL REGISTRATION NUMBER

DRKS00009713.