Myocardial Infarction With Nonobstructive Coronary Arteries (MINOCA): It's Time to Face Reality!

Approach to Imaging of Patients Presenting With Acute Coronary Syndrome With No Culprit Lesion Identified at Angiography

Chest pain is a common chief complaint among patients presenting to the emergency department. However, in the scenario where the clinical presentation is consistent with acute coronary syndrome and no culprit lesions are identified on angiography, clinicians and cardiac imagers should be informed of the differential diagnosis and appropriate imaging modalities used to investigate the potential causes. This review describes an imaging-based algorithm that highlights the diagnostic possibilities, their differentiating imaging features, and the important role of cardiovascular magnetic resonance imaging for narrowing the differential diagnosis.

Surgical treatment of left ventricular aneurysm in patients with prior myocardial infarction in the absence of obstructive coronary artery disease (MINOCA): a cohort study

BACKGROUND

There is a paucity of studies examining the treatment of patients with prior myocardial infarction in the absence of obstructive coronary arteries (MINOCA) and with a concomitant left ventricular aneurysm. Our study aims to illustrate the clinical characteristics and report the mid-term surgical outcomes in this distinct entity.

METHODS

Ten patients with MINOCA and left ventricular aneurysm were investigated. The MINOCA was diagnosed according to Scientific Statement from the American Heart Association. The indication for left ventricular reconstruction was as follows: clear evidence of both an aneurysmal and akinetic left ventricle with a history of myocardial infarction accompanied by heart failure symptoms, angina, or ventricular arrhythmias. Major adverse cardiovascular and cerebrovascular events (MACCE), including death, myocardial infarction, stroke was considered the primary endpoints.

RESULTS

The median follow-up for the whole study population was 64.5 months. Seven MINOCA patients developed a left ventricular aneurysm within 4 years and three MINOCA patients were found to have a concomitant left aneurysm at the first admission. Before surgery, no patients were prescribed angiotensin-converting enzyme inhibitors. Statins, dual antiplatelet therapy, and β-blockers were prescribed in 2, 5, and 5 patients, respectively. After surgery, no MACCE occurred in the follow-up. There was a significant increase in ejection fraction (EF) in the follow-up (p = 0.0009).

CONCLUSIONS

Close monitoring and standard medical treatment are required before a left ventricular aneurysm occurs in MINOCA patients. Left ventricular reconstruction remains a viable option for MINOCA patients with left ventricular aneurysms and mid-term outcomes were satisfying in this distinct entity.

Diagnostic Puzzles and Cause-Targeted Treatment Strategies in Myocardial Infarction with Non-Obstructive Coronary Arteries: An Updated Review

Myocardial infarction with nonobstructive coronary arteries (MINOCA) is a distinct subtype of myocardial infarction (MI), occurring in about 8-10% of spontaneous MI cases referred for coronary angiography. Unlike MI with obstructive coronary artery disease, MINOCA's pathogenesis is more intricate and heterogeneous, involving mechanisms such as coronary thromboembolism, coronary vasospasm, microvascular dysfunction, dissection, or plaque rupture. Diagnosing MINOCA presents challenges and includes invasive and non-invasive strategies aiming to differentiate it from alternative diagnoses and confirm the criteria of elevated cardiac biomarkers, non-obstructive coronary arteries, and the absence of alternate explanations for the acute presentation. Tailored management strategies for MINOCA hinge on identifying the underlying cause of the infarction, necessitating systematic diagnostic approaches. Furthermore, determining the optimal post-MINOCA medication regimen remains uncertain. This review aims to comprehensively address the current state of knowledge, encompassing diagnostic and therapeutic approaches, in the context of MINOCA while also highlighting the evolving landscape and future directions for advancing our understanding and management of this intricate myocardial infarction subtype.

MINOCA and INOCA: Role in Heart Failure

PURPOSE OF REVIEW

Infarction (MINOCA) and ischaemia (INOCA) with non-obstructive coronary disease are recent non-conventional presentations of coronary syndromes that are increasingly recognised in the clinical arena, particularly with the availability of new cardiovascular imaging techniques. Both are related to heart failure (HF). MINOCA is not associated with benign outcomes, and HF is among the most prevalent events. Regarding INOCA, microvascular dysfunction has also been found to associate with HF, particularly with preserved ejection fraction (HFpEF).

RECENT FINDINGS

Regardless of the several aetiologies underlying HF in MINOCA, it is likely related to LV dysfunction, where secondary prevention is not yet clearly established. Regarding INOCA, coronary microvascular ischaemia has been associated to endothelial dysfunction leading ultimately to diastolic dysfunction and HFpEF. MINOCA and INOCA are clearly related to HF. In both, there is a lack of studies on the identification of the risk factors for HF, diagnostic workup and, importantly, the appropriate primary and secondary prevention strategies.

Recurrent Angina in a Patient With Myocardial Infarction With Non-obstructive Coronary Arteries

The ubiquity of coronary angiography has increased the identification of myocardial infarction with non-obstructive coronary arteries. Currently among cardiologists, there is neither a consensus nor comprehensive diagnostic blueprint for accurate evaluation of patients with myocardial infarction with non-obstructive coronary arteries. We present a case of a patient with recurrent chest pain. A diagnosis of myocardial infarction with non-obstructive coronary arteries secondary to coronary artery vasospasm was determined with the use of multimodality imaging cardiac imaging.

Myocardial infarction with non-obstructive coronary arteries: Etiology, diagnosis, treatment and prognosis

Myocardial infarction with non-obstructive coronary arteries (MINOCA) is responsible for 10% of myocardial infarctions. Previously, patients were thought to have good prognosis, but evidence-based management and treatment strategies were scarce. Today, researchers and physicians recognize MINOCA as a condition with non-trivial mortality and morbidity. Therapeutic strategies are highly dependent on the underlying disease mechanism in each patient. However, to reach a diagnosis of MINOCA, a multimodal approach is required and, even with an optimal work-up, the cause remains unknown in 8-25% of patients. Research has been growing and position papers from the European Society of Cardiology (ESC) and the American Heart Association/American College of Cardiology have been published, and MINOCA has been included in the more recent ESC guidelines on myocardial infarction. Nonetheless, some clinicians still assume that the absence of coronary obstruction excludes the possibility of acute myocardial infarction. Therefore, in the present paper, we aim to compile and present the available data on the etiology, diagnosis, treatment, and prognosis of MINOCA.

Case report: Acute toxic myocardial damage caused by 5-fluorouracil—from enigma to success

Considering the pandemic of both cardiovascular diseases and oncological diseases, there is an increasing need for the use of chemotherapy, which through various pathophysiological mechanisms leads to damage to heart function. Cardio toxicity of chemotherapy drugs can manifest itself in a variety of clinical manifestations, which is why establishing a valid diagnosis is a real mystery for clinicians. Acute systolic heart failure (AHF) due to the use of 5-fluorouracil (5-FU) is a rare occurrence if it is not associated with myocardial infarction, myocarditis or Takotsubo cardiomyopathy. Therefore, we decided to present a case of an 52-year-old male who was diagnosed with stage IV RAS wild-type adenocarcinoma of the rectum and in whom the direct toxic effect 5-FU is the main reason for the appearance of toxic cardiomyopathy.

MINOCA: One Size Fits All? Probably Not—A Review of Etiology, Investigation, and Treatment

Myocardial infarction with non-obstructive coronary arteries (MINOCA) is a heterogeneous group of conditions that include both atherosclerotic (coronary plaque disruption) and non-atherosclerotic (spontaneous coronary artery dissection, coronary artery spasm, coronary artery embolism, coronary microvascular dysfunction, and supply–demand mismatch) causes resulting in myocardial damage that is not due to obstructive coronary artery disease. Failure to identify the underlying cause may result in inadequate and inappropriate therapy in these patients. The cornerstone of managing MINOCA patients is to identify the underlying mechanism to achieve the target treatment. Intravascular imaging is able to identify different morphologic features of coronary plaques, while cardiac magnetic resonance is the gold standard for detection of myocardial infarction in the setting of MINOCA. In this review, we summarize the relevant clinical issues, contemporary diagnosis, and treatment options of MINOCA.

Gender Differences in Guideline-Directed Medical Therapy for Cardiovascular Disease Among Young Veterans

BACKGROUND

There is an increasing burden of cardiovascular disease, including coronary artery disease (CAD) and heart failure (HF), among women Veterans. Clinical practice guidelines recommend multiple pharmacotherapies that can reduce risk of mortality and adverse cardiovascular outcomes.

OBJECTIVE

To determine if there are disparities in the use of guideline-directed medical therapy by gender among Veterans with incident CAD and HF.

DESIGN

Retrospective.

PARTICIPANTS

Veterans (934,504; 87.8% men and 129,469; 12.2% women) returning from Operations Enduring Freedom, Iraqi Freedom, and New Dawn.

MAIN MEASURES

Differences by gender in the prescription of Class 1, Level of Evidence A guideline-directed medical therapy among patients who developed incident CAD and HF at 30 days, 90 days, and 12 months after diagnosis. For CAD, medications included statins and antiplatelet therapy. For HF, medications included beta-blockers and renin-angiotensin-aldosterone system inhibitors.

KEY RESULTS

Overall, women developed CAD and HF at a younger average age than men (mean 45.8 vs. 47.7 years, p<0.001; and 43.7 vs. 45.4 years, p<0.02, respectively). In the 12 months following a diagnosis of incident CAD, the odds of a woman receiving a prescription for at least one CAD drug was 0.85 (95% confidence interval [CI], 0.68-1.08) compared to men. In the 12 months following a diagnosis of incident HF, the odds of a woman receiving at least one HF medication was 0.54 (95% CI, 0.37-0.79) compared to men.

CONCLUSIONS

Despite guideline recommendations, young women Veterans have approximately half the odds of being prescribed guideline-directed medical therapy within 1-year after a diagnosis of HF. These results highlight the need to develop targeted strategies to minimize gender disparities in CVD care to prevent adverse outcomes in this young and growing population.

A complicated case of myocardial infarction with nonobstructive coronary arteries with an underlying pheochromocytoma: a case report

BACKGROUND

The signs and symptoms of pheochromocytoma can imitate those of many other diseases, which may result in confusion. Therefore, diagnosing and treating secondary hypertension due to pheochromocytoma in deteriorating patients becomes challenging.

CASE PRESENTATION

A 63-year-old female patient presented to the emergency room with severe and progressive nausea. The initial diagnosis was an acute myocardial infarction based on ST-segment depression on electrocardiogram and elevated cardiac markers. Elective coronary angiography revealed nonobstructive coronary arteries. However, she suffered from a complicated clinical course for several weeks during her life-or-death crisis. She was subsequently diagnosed with a cerebral hemorrhage and a pheochromocytoma. It is unclear whether her initial presentation was due to the neurogenic stunned myocardium caused by a cerebral hemorrhage or type 2 myocardial infarction caused by a pheochromocytoma, or both. However, this case showed the significance of accurately diagnosing and treating underlying causes in patients presenting with myocardial infarction with nonobstructive coronary arteries. Early diagnosis and treatment of the pheochromocytoma may have prevented the complications experienced by the patient.

CONCLUSIONS

A catecholamine surge and blood pressure fluctuation caused severe complications. When a patient presents with an unusual clinical presentation, secondary hypertension due to pheochromocytoma should be suspected.

Association between Initial Serum Total Bilirubin and Clinical Outcome in Myocardial Infarction with Non-Obstructive Coronary Arteries

Background: Liver function parameters, particularly serum total bilirubin (TB), are closely associated with cardiovascular diseases. However, the impact of serum TB among patients with myocardial infarction and non-obstructive coronary (MINOCA) remains unknown. Our study investigated the relationship between serum TB at admission and long-term adverse clinical outcomes in MINOCA patients. Methods: A total of 273 consecutive MINOCA patients were categorized into low and high serum TB groups based on the optimal cut-off of 0.9 mg/dl. The primary endpoint was major adverse cardiovascular events (MACE), including cardiac death, non-fatal MI, heart failure, and angina rehospitalization. Receiver-operating characteristic, Cox regression, and Kaplan-Meier analyses were used to evaluate the association of high serum TB with cardiovascular outcomes. Results: High serum TB was found in 68 (24.9%) patients. The incidence of MACE was higher in the high TB group than in the low TB group after a median follow-up of 28 months (30.9 vs. 17.1%, P=0.015). The Kaplan-Meier curve analysis also indicated that patients in the high TB group had a higher risk of developing MACE (log-rank P=0.023). Cox regression analysis showed that high serum TB (>0.9mg/dl) significantly correlated with increased MACE risk (HR=1.90, 95%CI: 1.12-3.22, P=0.018). After adjusting for numerous clinical variables, the high serum TB remained significantly associated with an increased risk of MACE (HR=2.04, 95%CI: 1.05-3.94, P=0.034). Conclusion: High initial serum TB (>0.9mg/dl) is a robust predictor of poor clinical outcomes among MINOCA patients. In clinical settings, assessing serum TB at admission may help identify high-risk patients presenting with MINOCA.

Clinical presentation and management of myocardial infarction with nonobstructive coronary arteries (MINOCA): A literature review

Myocardial Infarction with Nonobstructive Coronary Arteries (MINOCA), as the name implies, is an acute myocardial infarction (MI) in the absence of significant coronary artery obstruction. Diagnosis and management of such cases have been challenging. There are many etiologies of MINOCA including coronary artery spasm, coronary microvascular dysfunction, plaque disruption, spontaneous coronary thrombosis or emboli, spontaneous coronary artery dissection, or cardiomyopathies. In this paper, the pathophysiology, diagnostic work-up, and clinical management for each subtype are described, and an overarching approach on how to evaluate and manage a patient presenting with MINOCA.

MINOCA: a heterogenous group of conditions associated with myocardial damage

Myocardial infarction with non-obstructive coronary arteries (MINOCA) was first described over 80 years ago. The term has been widely and inconsistently used in clinical practice, influencing various aspects of disease classification, investigation and management. MINOCA encompasses a heterogenous group of conditions that include both atherosclerotic and non-atherosclerotic disease resulting in myocardial damage that is not due to obstructive coronary artery disease. In many ways, it is a term that describes a moment in the diagnostic pathway of the patient and is arguably not a diagnosis. Central to the definition is also the distinction between myocardial infarction and injury. The universal definition of myocardial infarction distinguishes acute myocardial infarction, including those with MINOCA, from other causes of myocardial injury by the presence of clinical evidence of ischaemia. However, these ischaemic features are often non-specific causing diagnostic confusion, and can create difficulties for patient management and follow-up. The purpose of this review is to summarise our current understanding of MINOCA and highlight important issues relating to the diagnosis, investigation and management of patients with MINOCA.

Coronary artery spasm-induced acute myocardial infarction in patients with myocardial infarction with non-obstructive coronary arteries

Coronary artery spasm-induced acute myocardial infarction (CASIAMI) is one of the etiologies of myocardial infarction with non-obstructive coronary arteries (MINOCA). We retrospectively analyzed the incidence and clinical characteristics of Japanese patients with CASIAMI and non-obstructive coronary arteries. We experienced 62 patients with MINOCA (10 thrombosis, 7 unknown causes, and 45 CASIAMI) among 991 patients with suspected AMI. Pharmacological spasm provocation testing was performed in 37 patients. CASIAMI without obstructive coronary arteries was found in 4.5% of patients with suspected AMI and was observed in 73% of patients with MINOCA. Patients with CASIAMI were frequently males and had relatively small AMIs. Spontaneous spasm was recognized in 8 patients. We could reproduce provoked spasm in 37 patients with MINOCA, including 23 patients with multiple spasm. No patients died during the follow-up period. The clinical outcomes in patients with CASIAMI under optimal coronary vasodilators were satisfactory.

The role of a comprehensive two-step diagnostic evaluation to unravel the pathophysiology of MINOCA: A review

The role of cardiac magnetic resonance (CMR) in identifying mechanisms for myocardial infarction with non-obstructed coronary arteries (MINOCA) is well established. Recent reports have highlighted the potentially key role of invasive management in this diagnostic process. Intravascular ultrasound (IVUS) and optical coherence tomography (OCT) allow precise evaluation of coronary anatomy, and assessment of coronary physiology in the catheter laboratory provides information on the hemodynamic significance of sub-critical atherosclerosis and on coronary microvascular dysfunction (CMD). We reviewed the evidence for the contribution of invasive diagnostic techniques in identifying provisional causes for MINOCA. Overall, among 82 studies including 8457 patients were selected. In the acute phase, 16 studies with IVUS or OCT (1207 patients) disclosed that plaque disruption and spontaneous coronary artery dissection had a pooled prevalence of 38% (95% confidence intervals (CI): 29% to 51%) and 16% (95% CI: 9% to 27%), respectively. In 18 studies, coronary function testing (1449 patients) showed a pooled prevalence of spontaneous and/or provoked epicardial coronary spasm of ~28% (95% CI:17% to 41%). In 3 studies (456 patients), the pooled prevalence of CMD was ~32% (95% CI: 20% to 49%). In the subacute phase, 42 CMR studies (5821 patients) showed that a pooled prevalence of myocarditis, takotsubo syndrome and cardiomyopathy of 26% (95% CI: 12% to 40%), 11% (95% CI: 5% to 25%), and 7% (95% CI: 1% to 19%), respectively. In 12 studies on thrombophilia screening (n = 834), the pooled prevalence of thrombotic disorder was ~11% (95% CI: 7%% to 25%). In conclusion, the pathophysiology of MINOCA can be established in the majority of cases using both invasive and non-invasive tools to provide direction for appropriate management.

Prevalence, Clinical Factors, and Outcomes Associated With Myocardial Infarction With Nonobstructive Coronary Artery

BACKGROUND

Myocardial infarction with nonobstructive coronary arteries (MINOCA) is an underrecognized clinical problem in patients presenting with acute coronary syndrome. Various clinical disorders lead to MINOCA thus making treatment and diagnosis a challenge. We aimed to compare the clinical factors and outcomes of patients with MINOCA versus obstructive disease [myocardial infarction due to coronary artery disease (MI-CAD)] in a largely rural health system.

METHODS

Between May 1, 2009 and June 24, 2019, all consecutive ST-segment elevation myocardial infarction patients at Essentia Health were prospectively examined. We categorized patients into MI-CAD (obstructive plaque ≥ 50% with revascularization) or MINOCA (obstructive plaque < 50% with exclusion of other alternative cause). Outcomes included 30-day and 1-year all-cause mortality, 30-day all-cause readmission and 30-day cardiac readmission.

RESULTS

There were 2170 patients included in the study; 2097 (96.6 %) had MI-CAD and 73 (3.4%) met the definition of MINOCA. Within the MINOCA group, the 3 most common presentations were supply-demand mismatch (28.8%), spontaneous coronary artery dissection (9.6%), and other etiology (60.3%). Only 10 (13 %) MINOCA patients had cardiac magnetic resonance imaging studies obtained within 6 months. MINOCA patients were younger 61.6 versus 63.4 years with higher left ventricular function 51.6% versus 50.4% with less likelihood of prior myocardial infarction 4.1% versus 15.5% or congestive heart failure 2.7% versus 6.3% (P < 0.05). Compared with MI-CAD patients, MINOCA patients had similar 30-day mortality (7.1% vs. 8.2%; P = 0.70), 1-year mortality (10.4% vs. 8.2 %; P = 0.55), and 30-day cardiac readmission (8.7% vs. 9.6%; P = 0.29). MINOCA patients were less likely to be discharged on aspirin, betablockers, angiotensin-converting enzyme inhibitor/angiotensin receptor blockers, or statins (P < 0.05).

CONCLUSION

Though there was no difference in readmission and mortality between MINOCA and MI-CAD; use of secondary prevention medications and cardiac rehabilitation referral was low in MINOCA patients. Prospective studies will be relevant to assess effective medical therapy to improve outcomes in MINOCA patients.

Myocardial infarction with nonobstructive coronary artery disease (MINOCA): a review of pathophysiology and management

PURPOSE OF REVIEW

Myocardial infarction with nonobstructive coronary artery disease (MINOCA) (≥ 50% stenosis) accounts for 5-8% of acute coronary syndrome (ACS) presentations. The demographic characteristics, risk factors, and management of patients with MINOCA differ from those with atherosclerotic ACS. The objective of this review is to provide a contemporary understanding of the epidemiology, pathophysiology, clinical presentation, and management of MINOCA.

RECENT FINDINGS

MINOCA is increasingly being recognized as an important and distinct cause of myocardial infarction among patients presenting with ACS. The predominant pathophysiologic mechanisms of MINOCA include both coronary (epicardial vasospasm, coronary microvascular disorder, spontaneous coronary artery dissection, coronary thrombus/embolism) and noncoronary (Takotsubo cardiomyopathy, myocarditis) pathologies. Coronary imaging with intravascular ultrasound and optical coherent tomography, coronary physiology testing, and cardiac magnetic resonance imaging offers important investigative modalities to facilitate diagnosis for appropriate management of MINOCA patients.

SUMMARY

MINOCA is an important cause of ACS observed in certain patients with unique challenges for diagnosis and management. A high index of suspicion and a comprehensive diagnostic evaluation are critical for early recognition and successful management.

Secondary Prevention of Cardiovascular Disease in Women: Closing the Gap

Cardiovascular disease (CVD) remains the leading cause of death in women globally. Younger women (<55 years of age) who experience MI are less likely to receive guideline-directed medical therapy (GDMT), have a greater likelihood of readmission and have higher rates of mortality than similarly aged men. Women have been under-represented in CVD clinical trials, which limits the generalisability of results into practice. Available evidence indicates that women derive a similar benefit as men from secondary prevention pharmacological therapies, such as statins, ezetimibe, proprotein convertase subtilisin/kexin type 9 inhibitors, icosapent ethyl, antiplatelet therapy, sodium-glucose cotransporter 2 inhibitors and glucagon-like peptide-1 receptor agonists. Women are less likely to be enrolled in cardiac rehabilitation programs than men. Mitigating risk and improving outcomes is dependent on proper identification of CVD in women, using appropriate GDMT and continuing to promote lifestyle modifications. Future research directed at advancing our understanding of CVD in women will allow us to further develop and tailor CVD guidelines appropriate by sex and to close the gap between diagnoses, treatment and mortality.

Association of Timing of Electrocardiogram Acquisition After Return of Spontaneous Circulation With Coronary Angiography Findings in Patients With Out-of-Hospital Cardiac Arrest

IMPORTANCE

Electrocardiography (ECG) is an important tool to triage patients with out-of-hospital cardiac arrest (OHCA) after return of spontaneous circulation (ROSC). An immediate coronary angiography after ROSC is recommended only in patients with an ECG that is diagnostic of ST-segment elevation myocardial infarction (STEMI). To date, the benefit of this approach has not been demonstrated in patients with a post-ROSC ECG that is not diagnostic of STEMI.

OBJECTIVE

To assess whether the time from ROSC to ECG acquisition is associated with the diagnostic accuracy of ECG for STEMI.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective, multicenter cohort study (the Post-ROSC Electrocardiogram After Cardiac Arrest study) analyzed consecutive patients older than 18 years who were resuscitated from OHCA between January 1, 2015, and December 31, 2018, and were admitted to 1 of the 3 participating centers in Europe (Pavia, Italy; Lugano, Switzerland; and Vienna, Austria).

EXPOSURE

Only patients who underwent coronary angiography during hospitalization and who acquired a post-ROSC ECG before the angiography were enrolled. Patients with a nonmedical cause of OHCAs were excluded.

MAIN OUTCOMES AND MEASURES

The primary end point was false-positive ECG findings, defined as the percentage of patients with post-ROSC ECG findings that met STEMI criteria but who did not show obstructive coronary artery disease on angiography that was worthy of percutaneous coronary angioplasty.

RESULTS

Of 586 consecutive patients who were admitted to the 3 participating centers, 370 were included in the analysis (287 men [77.6%]; median age, 62 years [interquartile range, 53-70 years]); 121 (32.7%) were enrolled in the participating center in Pavia, Italy; 38 (10.3%) in Lugano, Switzerland; and 211 (57.0%) in Vienna, Austria. The percentage of false-positive ECG findings in the first tertile of ROSC to ECG time (≤7 minutes) was significantly higher than that in the second (8-33 minutes) and third (>33 minutes) tertiles: 18.5% in the first tertile vs 7.2% in the second (odds ratio [OR], 0.34; 95% CI, 0.13-0.87; P = .02) and 5.8% in the third (OR, 0.27; 95% CI, 0.15-0.47; P < .001). These differences remained significant when adjusting for sex (≤7 minutes: reference; 8-33 minutes: OR, 0.32; 95% CI, 0.12-0.85; P = .02; >33 minutes: OR, 0.26; 95% CI, 0.14-0.47; P < .001), age (≤7 minutes: reference; 8-33 minutes: OR, 0.34; 95% CI, 0.13-0.89; P = .03; >33 minutes: OR, 0.27; 95% CI, 0.15-0.46; P < .001), number of segments with ST-elevation (≤7 minutes: reference; 8-33 minutes: OR, 0.35; 95% CI, 0.15-0.81; P = .01; >33 minutes: OR, 0.28; 95% CI, 0.15-0.52; P < .001), QRS duration (≤7 minutes: reference; 8-33 minutes: OR, 0.35; 95% CI, 0.14-0.87; P = .02; >33 minutes: OR, 0.27; 95% CI, 0.15-0.48; P < .001), heart rate (≤7 minutes: reference; 8-33 minutes: OR, 0.35; 95% CI, 0.13-0.93; P = .04; >33 minutes: OR, 0.29; 95% CI, 0.15-0.55; P < .001), epinephrine administered (≤7 minutes: reference; 8-33 minutes: OR, 0.35; 95% CI, 0.13-0.98; P = .045; >33 minutes: OR, 0.27; 95% CI, 0.16-0.48; P < .001), shockable initial rhythm (≤7 minutes: reference; 8-33 minutes: OR, 0.35; 95% CI, 0.13-0.96; P = .04; >33 minutes: OR, 0.26; 95% CI, 0.15-0.46; P < .001), and 3 or more shocks administered (≤7 minutes: reference; 8-33 minutes: OR, 0.36; 95% CI, 0.13-1.00; P = .05; >33 minutes: OR, 0.27; 95% CI, 0.16-0.48; P < .001) in bivariable analyses.

CONCLUSIONS AND RELEVANCE

This study suggests that early ECG acquisition after ROSC in patients with OHCA is associated with a higher percentage of false-positive ECG findings for STEMI. It may be reasonable to delay post-ROSC ECG by at least 8 minutes after ROSC or repeat the acquisition if the first ECG is diagnostic of STEMI and is acquired early after ROSC.

Dual antiplatelet therapy in myocardial infarction with non-obstructive coronary artery disease - insights from a nationwide registry

INTRODUCTION AND OBJECTIVES

Dual antiplatelet therapy (DAPT) is a mainstay for myocardial infarction (MI) therapy. However, in patients with myocardial infarction with non-obstructive coronary artery disease (MINOCA), clear recommendations are lacking in the literature. This study aims to identify the cases in which DAPT is currently prescribed at discharge for MINOCA.

METHODS

The authors analyzed a cohort of patients from a multicenter national registry enrolling patients who suffered their first MI between 2010 and 2017, and underwent coronary angiography revealing absence of stenosis ≥50%. Individual antithrombotic therapy was identified. A logistic regression analysis was applied to search for predictors of DAPT.

RESULTS

From a total of 16 237 patients analyzed, 709 (4.4%) were categorized as MINOCA. Mean age was 64±13 years, 46.3% (n=409) were females. 390 (55.0%) of MINOCA patients were discharged on DAPT. Males (OR 1.67, CI 95 [1.05-2.38], p=0.027), active smokers (OR=1.82, CI 95 [1.05-3.16], p=0.033), previous percutaneous intervention (OR 3.18, CI 95 [1.48-6.81], p=0.003), ST elevation MI (OR 2.70, CI 95 [1.59-4.76], p<0.001) and sinus rhythm at admission (OR=3.94, CI 95 [2.07-7.48], p<0.001) were independent predictors of DAPT use.

CONCLUSION

In this nationwide registry, DAPT was prescribed at discharge in 55% of MINOCA patients. Beyond sinus rhythm, the variables presented as independent predictors for DAPT use identify subgroups of patients who are classified as more prone to thrombotic events. The issue of how to handle antithrombotic agents in MINOCA patients is a topic open for discussion.

Impact of Myocardial Bridge on Life‐Threatening Ventricular Arrhythmia in Patients With Implantable Cardioverter Defibrillator

Background

Myocardial bridge (MB), common anatomic variant, is generally considered benign, while previous studies have shown associations between MB and various cardiovascular pathologies. This study aimed to investigate for the first time possible impact of MB on long‐term outcomes in patients with implantable cardioverter defibrillator, focusing on life‐threatening ventricular arrhythmia (LTVA).

Methods and Results

This retrospective analysis included 140 patients with implantable cardioverter defibrillator implantation for primary (n=23) or secondary (n=117) prevention of sudden cardiac death. Angiographically apparent MB was identified on coronary angiography as systolic milking appearance with significant arterial compression. The primary end point was the first episode(s) of LTVA defined as appropriate implantable cardioverter defibrillator treatments (antitachyarrhythmia pacing and/or shock) or sudden cardiac death, assessed for a median of 4.5 (2.2–7.1) years. During the follow‐up period, LTVA occurred in 37.9% of patients. Angiographically apparent MB was present in 22.1% of patients; this group showed younger age, lower rates of coronary risk factors and ischemic cardiomyopathy, higher prevalence of vasospastic angina and greater left ventricular ejection fraction compared with those without. Despite its lower risk profiles above, Kaplan–Meier analysis revealed significantly lower event‐free rates in patients with versus without angiographically apparent MB. In multivariate analysis, presence of angiographically apparent MB was independently associated with LTVA (hazard ratio, 4.24; 95% CI, 2.39–7.55; P <0.0001).

Conclusions

Angiographically apparent MB was the independent determinant of LTVA in patients with implantable cardioverter defibrillator. Although further studies will need to confirm our findings, assessment of MB appears to enhance identification of high‐risk patients who may benefit from closer follow‐up and targeted therapies.

Age-Stratified Sex Disparities in Care and Outcomes in Patients With ST-Elevation Myocardial Infarction

BACKGROUND

Women are undertreated and have worse clinical outcomes than men after acute myocardial infarction. It remains uncertain whether the sex disparities in treatments and outcomes persist in the contemporary era and whether they affect all age groups equally.

METHODS

Using the National Inpatient Sample (NIS) registry, we evaluated 1,260,200 hospitalizations for ST-elevation myocardial infarction (STEMI) between 2010 and 2016, of which 32% were for women. The age-stratified sex differences in care measures and mortality were examined. Stepwise multivariable adjustment models, including baseline comorbidities, hospital characteristics, and reperfusion and revascularization therapies, were used to compare measures and outcomes between women and men across different age subgroups.

RESULTS

Overall, women with STEMI were older than men and had more comorbidities. Women were less likely to receive fibrinolytic therapy, percutaneous coronary intervention (PCI), and coronary artery bypass surgery across all age subgroups. Women with STEMI overall experienced higher unadjusted in-hospital mortality (11.1% vs 6.8%; adjusted odds ratio [OR] = 1.039, 95% confidence interval [CI]: 1.003-1.077), which persisted after multivariable adjustments. However, when stratified by age, the difference in mortality became non-significant in most age groups after stepwise multivariable adjustment, except among the youngest patients 19-49 years of age with STEMI (women vs men: 3.9% vs 2.6%; adjusted odds ratio = 1.259, 95% confidence interval: 1.083-1.464).

CONCLUSIONS

Women with STEMI were less likely to receive reperfusion and revascularization therapies and had higher in-hospital mortality and complications compared with men. Younger women with STEMI (19-49 years of age) experienced higher in-hospital mortality that persisted after multivariable adjustment.

A review of diagnosis, etiology, assessment, and management of patients with myocardial infarction in the absence of obstructive coronary artery disease

Myocardial infarction (MI) in the absence of obstructive coronary artery disease (MINOCA) is prevalent in around 5% of acute myocardial infarction (AMI) presentations. MINOCA is a heterogeneous entity with many different etiologies. It is important for health care providers to familiarize themselves with the disease process, presentation, and possible underlying causes in order to guide appropriate management strategies. In this article, the authors review the contemporary definition, etiologies and assessment, and management for AMI patients with MINOCA.

A Review of the Evidence for Treatment of Myocardial Infarction With Nonobstructive Coronary Arteries

Myocardial infarction (MI) with non-obstructive coronary arteries (MINOCA) is reported in 6% of patients with acute MI referred for catheterization. Because of the complex etiology and a limited amount of evidence, the treatment of MINOCA remains elusive. The etiology of MINOCA manifests from several causes including plaque disruption or erosion, epicardial coronary artery vasospasm, and coronary microvascular dysfunction. In addition, spontaneous coronary artery dissection, takotsubo, and myocarditis have been identified as contributing to the diagnosis of MINOCA. Patients with MINOCA are frequently young, non-white females with fewer traditional risk factors compared with those with an MI caused by obstructive coronary disease. Moreover, women who suffered an MI are 5 times more likely to be diagnosed with MINOCA with a trend for worse outcomes compared with men. The increased recognition/diagnosis of MINOCA has highlighted a gap in our understanding of the treatment of MINOCA. This review identified that there is a paucity of evidence on treatment strategies for patients clinically diagnosed with MINOCA, but more importantly that MINOCA should be viewed as a "syndrome" with many different pathologic causes. This suggests that a standard protocol may not be useful for patients with MINOCA. Given the ongoing debate over the complexity of MINOCA, the main focus in the management of MINOCA should be to identify the underlying mechanism for targeted therapies that may optimize outcomes.

Myocardial Infarction with Nonobstructive Coronary Arteries (MINOCA): A Review of the Current Position

Myocardial infarction with nonobstructive coronary arteries (MINOCA) remains a puzzling clinical entity that is characterized by clinical evidence of myocardial infarction (MI) with normal or near-normal coronary arteries on angiography (stenosis <50%). Major advances in understanding this condition have been made in recent years. The precise pathogenesis is poorly understood and is being studied and examined further. Guidelines indicate that MINOCA is a group of heterogeneous diseases with different mechanisms of pathology. Since there are multiple possible pathological mechanisms, it is not certain that the classical secondary prevention and treatment strategy for MI with obstructive coronary artery disease (MI-CAD) is optimal for MINOCA patients. The prognosis and predictors for MINOCA patients remain unclear. Although the prognosis is slightly better for MINOCA patients than for MI-CAD patients, MINOCA isn't always benign. The aim of this paper was to review the literature and evaluate MINOCA epidemiology, clinical features, etiology, diagnosis, treatment, and prognosis.

MINOCA: The caveat of absence of coronary obstruction in myocardial infarction

AIMS

Whether patients with MINOCA (myocardial infarction with non-obstructive coronary arteries) have better outcomes than patients with obstructive coronary artery disease remains contradictory. The current study focussed on the clinical profile and prognosis of MINOCA patients.

METHODS AND RESULTS

We performed a retrospective analysis of patients with acute coronary syndrome (ACS) admitted to the Isala hospital in Zwolle, the Netherlands, between 2006 and 2014. A total of 7693 patients were categorized into three groups: MINOCA, single-vessel obstructive ACS (SV-ACS), and multi-vessel obstructive ACS (MV-ACS). MINOCA patients (5.2% of the total population) were more likely to be female (51.5% vs. 30.3% and 26.0% in SV-ACS and MV-ACS, respectively, p < 0.001 for both). The prevalence of risk factors in the MINOCA group was in between the SV-ACS and MV-ACS groups. Logistic regression revealed a lower odds of dying in SV-ACS (odds ratio (OR) = 0.70 (p = 0.04)) and a similar odds in MV-ACS (OR = 0.88, p = 0.45) compared to MINOCA.

CONCLUSIONS

Patients with MINOCA show an 'intermediate' risk profile with mortality rates in between those of both ACS groups. Hence, MINOCA should be recognised as a potential risk factor for mortality, requiring adequate treatment and follow-up.

Sex Differences in Coronary Artery Calcium and Long-term CV Mortality

PURPOSE OF REVIEW

To summarize differences in plaque depositions, coronary artery calcium (CAC) scoring, and the role of CAC in predicting atherosclerotic cardiovascular disease (ASCVD) mortality in men and women.

RECENT FINDINGS

Women have coronary plaque that is more lipid-rich, dense, and less calcified than their male counterparts. CAC scoring has emerged as a useful tool to quantify ASCVD burden. However, recent evidence favors the use of sex-adjusted CAC cutoffs for women to account for the relatively lower overall CAC burden and therefore risk stratify women appropriately. Several studies have identified CAC distribution patterns in women associated with increased CV mortality, particularly the number of lesions involved, CAC volume, and size. Multiple studies have shown that the pathophysiology and associated risks of ASCVD are different in women when compared with men. CAC scoring is a tool that is widely being used for ASCVD risk stratification. Recent studies have shown that although men have higher CAC burdens, women are more likely to develop plaque erosions with non-calcified plaque that carries a greater risk for cardiovascular events. Providers should be aware of sex-specific CAC patterns carrying increased mortality risk for women, particularly increasing lesion size and number. Given the differences in plaque composition and distribution, revised sex-adjusted CAC scoring is suggested to better risk stratify patients, especially those deemed intermediate risk, and decrease CV mortality.

Reperfusion and Time to Presentation in Women: Too Little Too Late

See Editorial by Cenko et al.