Long-Term Prognosis of Patients with Myocardial Infarction Type 1 and Type 2 with and without Involvement of Coronary Vasospasm

COVID-19 and myocardial injury: Targeting elevated biomarkers for potential novel therapies

BACKGROUND

The prevalence of COVID-19 as the primary diagnosis among hospitalized patients with myocardial injury has increased during the pandemic and targeting elevated oxidant stress and inflammatory biomarkers may offer a potential role for novel therapies to improve outcomes.

METHODS

At a single VA Medical Center from January 1 through December 31, 2021, troponin assays from patients being evaluated in the Emergency Room for consideration of admission were analyzed and peak levels from each patient were considered abnormal if exceeding the Upper Reference Limit (URL). Among admitted patients with an elevated troponin level, ICD-10 diagnoses were categorized, biomarker elevations were recorded, and independent predictors of death in patients with COVID-19 were determined at a median of 6-months following admission.

RESULTS

Of 998 patients, 399 (40 %) had a negative troponin and were not included in the analysis. Additional patients with an elevated troponin were also excluded, either because they were not admitted (n = 68) or had a final diagnosis of Type 1 MI (n = 117). Of the remaining 414 patients with an elevated peak troponin, COVID-19 was the primary diagnosis in 43 patients (10 %) and was the 4th most common diagnosis of patients admitted with myocardial injury behind congestive heart failure, sepsis, and COPD or pneumonia. At a median of 6-months following admission, 18 (42 %) of the COVID-19 patients had died and independent predictors of death (Odd Ratio: Confidence Intervals) were age (1.18: 1.06‒1.37), Troponin level (Log 10 transformed) (16.54: 2.30‒266.65) and C-Reactive Protein (CRP) (1.30: 1.10‒1.65).

CONCLUSIONS

Newly diagnosed COVID-19 during the pandemic was a common cause of elevated troponin in hospitalized patients without a Type 1 MI. Age, peak troponin level and peak CRP level were independent predictors of poor outcomes and suggest a need to target these cardiac biomarkers, potentially with novel antioxidant or anti-inflammatory therapies.

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.

Analysis of Anti-Arrhythmic Impacts of Crocin through Estimation of Expression of Cx43 in Myocardial Infarction Using a Rat Animal Model

Arrhythmia is an important cause of death after myocardial infarction (MI). Different substances have been evaluated for their anti-arrhythmic effect in MI. This study was performed to evaluate the anti-arrhythmic impacts of crocin in an MI animal model (rat) by estimation of the expression of connexin 43 (Cx43). Fifty male Sprague-Dawley rats were grouped into 5 groups, each composed of 10 rats. The first group was regarded as the normal control group and the second one was considered as the MI group, which was caused by ligation of the left anterior descending artery. The other three groups received crocin 50 or 10 mg/kg/day or metoprolol 100 mg/kg/day for 1 week, following ligation of the left anterior descending artery. Evaluated outcomes were cardiac Cx43 expression, arrhythmia incidence, histological findings, and myocyte resting potential. Crocin-treated MI groups showed a significantly lower arrhythmia score than the non-treated MI group, 10 mg/kg/day (1.85 ± 0.55, p < 0.01) and 50 mg/kg/day (1.70 ± 0.33, p < 0.01). Groups that received crocin 10 mg/kg/day (66.30 ± 2.59, p < 0.01), crocin 50 mg/kg/day (68.10 ± 2.43, p < 0.01), and metoprolol 100 mg/kg/day (-63.54 ± 0.63 mV, p < 0.01) significantly prevented depolarization in comparison with the non-treated MI group. Expression of Cx43 mRNA in crocin 10 mg/kg/day (1.54 ± 0.24, p < 0.01), crocin 50 mg/kg/day (1.73 ± 0.09, p < 0.01), and metoprolol 100 mg/kg/day (1.75 ± 0.14, p < 0.01) treatment groups was significantly higher in comparison with the non-treated MI group. Crocin showed a preventive effect on the arrhythmogenic impact of MI in an experimental model of ischemic injury through an increase in expression of Cx43.

The Troponin Complex: Discriminating the Signal from the Noise

Patients presenting to the emergency department with consideration of an acute coronary syndrome (ACS) are risk-stratified with sensitive troponin assays. Among many patients who present with symptoms other than chest pain, they are admitted for observation if the troponin assay is above the upper reference limit of that specific assay. With the advent of high-sensitivity troponin assays, it is estimated that the prevalence of admissions for secondary myocardial infarctions, termed type 2 myocardial infarctions and myocardial injury, will increase by 100%. This is a heterogeneous population, and although adverse outcomes such as readmission and death are high, outcome-based therapies with guideline-directed treatments have not been advanced in this subset. As such, the clinician is often confused about the optimal treatment at hospital discharge. More studies should address the value of specific known therapies in this cohort that have been shown to improve outcomes in patients with an acute coronary syndrome or type 1 myocardial infarction.

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.

Long-term clinical outcomes of type 1 vs. type 2 myocardial infarction in patients who underwent angiography: data from the Korea acute myocardial infarction-national institute of health registry

BACKGROUND

In the cause of increase the clinical research observational evidence on type 2 myocardial infraction (T2MI), the study compared the characteristics of T2MI and T1MI with respect to major adverse cardiac events (MACE) and mortality as long-term outcomes from a large, nationwide, prospective Korean cohort registry.

METHODS

From 13,105 consecutively enrolled individuals in the Korea Acute Myocardial Infarction-National Institute of Health (KAMIR-NIH) registry between October 2011 and December 2015, 11,053 acute myocardial infarction (AMI) patients were divided into the T1MI (n=10,545) and T2MI (n=508) groups. All patients completed ≥3 years of follow-up.

RESULTS

The Kaplan-Meier curve analysis and Cox proportional hazard regression models showed that the cumulative rate of MACE was similar between the 2 groups (11.4% vs. 13.4%, log-rank P=0.185) at 3 years. However, the T2MI group showed higher rates of all-cause death [12.6% vs. 9.4%, log-rank P=0.019; hazard ratio (HR), 1.42; 95% CI: 1.08-1.85; P=0.012] and non-cardiac death (3.5% vs. 5.3%, log-rank P=0.043; HR, 1.55; 95% CI: 1.01-2.37; P=0.043) than the T1MI group. Male sex (HR 1.540; 95% CI: 1.218-1.947, P<0.001), old age (≥65 years; HR, 3.546; 95% CI: 2.645-4.753, P<0.001), low hemoglobin level (<12 g/dL; HR, 2.335; 95% CI: 1.841-2.961, P<0.001), high heart rate (>100 beats/min; HR, 1.852; 95% CI: 1.436-2.388, P<0.001), low glomerular filtration rate (GFR) (<60 mL/min/1.73 m2; HR, 2.373; 95% CI: 1.874-3.005, P<0.001), high body mass index (>25 kg/m2; HR, 0.644; 95% CI: 0.514-0.805, P<0.001), and low left ventricular ejection fraction (LVEF) (<40%; HR, 1.487; 95% CI: 1.095-2.020, P=0.011) were the independent predictors for 3-year non-cardiac mortality.

CONCLUSIONS

Although the 2 groups did not differ in MACE, the total mortality rate was higher in T2MI than in T1MI, especially non-cardiac mortality. The independent predictors for non-cardiac mortality were male sex, old age, anemia, low GFR, tachycardia, obesity, and low LVEF.

To the Future and Beyond: Recent Advances in the Application of Percutaneous Coronary Intervention

We are very fortunate to be practicing interventional cardiology during an era of rapid clinical and technological evolution, which allows us to offer potentially life-saving options for challenging cardiac conditions [...].

Role of acetylcholine spasm provocation test as a pathophysiological assessment in nonobstructive coronary artery disease

Coronary angiography (CAG) sometimes shows nonobstructive coronary arteries in patients with suspected angina or acute coronary syndrome (ACS). The high prevalence of nonobstructive coronary artery disease (CAD) in those patients has recently been reported not only in Japan but also in Western countries, and is clinically attracting attention. Coronary spasm is considered to be one of the leading causes of both suspected stable angina and ACS with nonobstructive coronary arteries. Coronary spasm could also be associated with left ventricular dysfunction leading to heart failure, which could be improved following the administration of calcium channel blockers. Because we rarely capture spontaneous attacks of coronary spasm with electrocardiograms or Holter recordings, an invasive diagnostic modality, acetylcholine (ACh) provocation test, can be useful in detecting coronary spasm during CAG. Furthermore, we can use the ACh-provocation test to identify high-risk patients with coronary spasm complicated with organic coronary stenosis, and then treat with intensive care. Nonobstructive CAD includes not only epicardial coronary spasm but also microvascular spasm or dysfunction that can be associated with recurrent anginal attacks and poor quality of life. ACh-provocation test could also be helpful for the assessment of microvascular spasm or dysfunction. We hope that cardiologists will increasingly perform ACh-provocation test to assess the pathophysiology of nonobstructive CAD.