Myocardial infarction in childhood: clinical analysis of 17 cases and medium term follow up of survivors

Myocardial Infarction in Children after COVID-19 and Risk Factors for Thrombosis

Acute myocardial infarction (AMI) in children is rather anecdotic. However, following COVID-19, some conditions may develop which may favor thrombosis, myocardial infarction, and death. Such a condition is Kawasaki-like disease (K-lD). K-lD appears in children as a subgroup of the multisystem inflammatory syndrome (MIS-C). In some cases, K-lD patients may develop giant coronary aneurysms. The evolution and characteristics of coronary aneurysms from K-lD appear to be different from classical Kawasaki disease (KD) aneurysms. Differences include a lower percentage of aneurysm formation than in non-COVID-19 KD, a smaller number of giant forms, a tendency towards aneurysm regression, and fewer thrombotic events associated with AMI. We present here a review of the literature on the thrombotic risks of post-COVID-19 coronary aneurysms, starting from a unique clinical case of a 2-year-old boy who developed multiple coronary aneurysms, followed by AMI. In dehydration conditions, 6 months after COVID-19, the boy developed anterior descending artery occlusion and a slow favorable outcome of the AMI after thrombolysis. This review establishes severity criteria and risk factors that predispose to thrombosis and AMI in post-COVID-19 patients. These may include dehydration, thrombophilia, congenital malformations, chronic inflammatory conditions, chronic kidney impairment, acute cardiac failure, and others. All these possible complications should be monitored during acute illness. Ischemic heart disease prevalence in children may increase in the post-COVID-19 era, due to an association between coronary aneurysm formation, thrombophilia, and other risk factors whose presence will make a difference in long-term prognosis.

Acute Myocardial Infarction in a 17-year-old High-school Girl

We report an unusual case of acute myocardial infarction in a high school girl. The patient was 17 years of age and had multiple coronary risk factors, including marked obesity with a body mass index (BMI) of 42.7 kg/m², dyslipidemia and glucose intolerance. She had been an on and off smoker since she was 13 years of age. Due to the recent Westernization of the lifestyle, the prevalence of metabolic syndrome in the young generation has been increasing in Japan. Cardiovascular disease based on lifestyle-related diseases may become more common in young people.

Myocardial Infarction in Neonates: A Diagnostic and Therapeutic Challenge

Neonatal acute myocardial infarction is an uncommon entity. We describe the case of a 4-day-old term baby who presented with respiratory distress and distal acrocyanosis. The chest radiograph demonstrated cardiomegaly without pleural effusion, and examination revealed hepatomegaly. An electrocardiogram revealed QS pattern in leads I, aVL, and V6, suggestive of ischemia. Cardiac enzymes were elevated, and echocardiogram revealed moderate left ventricular dysfunction with a thrombus at the level of the left atrial appendage. The patient required hemodynamic stabilization, vasodilatation to avoid congestive heart failure, and anticoagulation with heparin and aspirin. In the context of this unusual diagnosis, we reviewed our experience over the last 17 years as well as the existing literature on neonatal myocardial infarction.

Marijuana use and short-term outcomes in patients hospitalized for acute myocardial infarction

Marijuana use is increasing worldwide, and it is ever more likely that patients presenting with acute myocardial infarctions (AMI) will be marijuana users. However, little is known about the impact of marijuana use on short-term outcomes following AMI. Accordingly, we compared in-hospital outcomes of AMI patients with reported marijuana use to those with no reported marijuana use. We hypothesized that marijuana use would be associated with increased risk of adverse outcomes in AMI patients. Hospital records from 8 states between 1994–2013 were screened for patients with a diagnosis of AMI. Clinical profiles and outcomes in patients with reported use of marijuana were compared to patients without reported marijuana use. Short-term outcomes were defined as adverse events that occurred during hospitalization for an admitting diagnosis of AMI. The composite primary outcome included death, intraaortic balloon pump placement, (IABP), mechanical ventilation, cardiac arrest, and shock. In total, 3,854 of 1,273,897 AMI patients reported use of marijuana. The marijuana cohort was younger than (47.2 vs. 57.2, respectively) and had less coronary artery disease than the non-marijuana cohort. In multivariable analysis including age, race and common cardiac risk factors, there was no association between marijuana use and the primary outcome (p = 0.53), but marijuana users were more likely to be placed on mechanical ventilation (OR (odds ratio) 1.19, p = 0.004). Interestingly, marijuana-using patients were significantly less likely to die (OR 0.79, p = 0.016), experience shock (OR 0.74, p = 0.001), or require an IABP (OR 0.80, p = 0.03) post AMI than patients with no reported marijuana use. These results suggest that, contrary to our hypothesis, marijuana use was not associated with increased risk of adverse short-term outcomes following AMI. Furthermore, marijuana use was associated with decreased in-hospital mortality post-AMI.

Magnetic resonance imaging of cardiovascular thrombi in children

Cardiovascular thrombosis is rare in children and usually occurs in the presence of predisposing conditions, such as indwelling vascular catheters, tumors, aneurysms, ventricular dysfunction, or after surgery. Clots can occur in the cardiac chambers, arteries or veins, or inside conduits. Detection of thrombi is feasible with a variety of magnetic resonance imaging (MRI) techniques, including unenhanced methods but also contrast-enhanced MR angiography. In this essay we illustrate the MRI appearance of cardiovascular thrombosis in children and suggest an imaging protocol based on our clinical experience.

MRI of pediatric cardiac masses

OBJECTIVE

The purpose of this article is to describe the characteristic cardiac MRI features of primary and secondary cardiac tumors, including differentiation from masslike lesions, such as thrombus or focal myocardial hypertrophy.

CONCLUSION

The frequency and type of cardiac tumors in children differ from those in adults. Although transthoracic echocardiography is the initial imaging technique of choice for evaluation of cardiac tumors, cardiac MRI is an important complementary modality for characterization of the mass and effect on cardiac function.

An Unusual Case of Suspected Microvascular Angina in a Newborn

Myocardial ischemia in pediatric population is uncommon and usually due to congenital heart disease or extracardiac conditions leading to poor coronary perfusion. A 6-day-old newborn presented with respiratory distress and signs of heart failure. ECG, echocardiography, and laboratory results were consistent with myocardial ischemia. Coronary angiography was performed to exclude anomalous origin of coronary arteries, showing normal coronary artery origin and course. Thrombophilia and extra-cardiac causes were ruled out. Clinical conditions improved with mechanical ventilation and diuretics, enzyme levels lowered, repolarisation and systolic function abnormalities regressed, but ischemic electrocardiographic and echocardiographic signs still presented during intense crying. Becaues of suspicion of microvascular angina, therapy with ASA and beta-blocker was started. At 5 month followup, the baby was in good clinical condition and no more episodes were recorded. We believe it is an interesting case, as no similar cases have been recorded till now.

Acute myocardial infarction as the presenting symptom of systemic lupus erythematosus

We report a case of acute myocardial infarction due to non-antiphospholipid-related coronary artery thrombosis as the presenting manifestation of systemic lupus erythematosus in a young patient. We present the acute workup and the results of successful transcatheter coronary intervention. The causes of acute myocardial infarction and coronary artery thrombosis in pediatric patients are reviewed.

[Fulminant myocarditis presenting like acute myocardial infarction in a 6-year-old girl]

Acute myocarditis is a rare inflammatory cardiac disease in children with potentially fatal issue. Clinical findings are very variable from nausea and vomiting to acute cardiovascular collapse. The cardiac function can be reversible with circulatory support. We report the case of a 6-year-old girl with ECG changes like myocardial infarction and diagnosis of fulminant myocarditis. She developped rapidly a cardiogenic shock and died before treatment with mechanical circulatory support.

Changes in causes of sudden deaths by decade in patients with coronary arterial lesions due to Kawasaki disease

Over a 25-year period, we encountered 12 patients who died suddenly with coronary arterial lesions due to Kawasaki disease. We report their clinical course, and analyze the happenings of their deaths. Of the 12 patients, 10 were dead on arrival at hospital. Their age at death ranged from 13 months to 27 years, with a median of 16 years, and the interval from the onset of Kawasaki disease to death ranged from 2 months to 24 years. In 4 patients, death was found to be due to myocardial infarction, while in the remaining 8, it could not be determined. In 7 patients, coronary angiograms obtained less than 4 months after the acute onset of Kawasaki disease showed lesions bilaterally, most being giant aneurysms. Myocardial infarction had occurred in 6 patients prior to their death. In 1 patient of the late 1970s, who collapsed after running, cardiac sequels had not been suspected prior to autopsy. During the 1980s, 3 infants with bilateral giant aneurysms died within a year of the initial onset of Kawasaki disease, with acute myocardial infarction being the cause in 2 of them. In the late 1990s, and the 2000s, 5 patients died suddenly with left ventricular dysfunction, their ejection fractions being less than 40 percent more than 20 years after the initial onset of Kawasaki disease. Prior to their sudden deaths, they had had no cardiac events for many years, but had suffered previous myocardial infarctions. Multifocal premature ventricular contractions, and non-sustained ventricular tachycardia, are probable risk factors in such patients. Careful follow-up, checking for ventricular arrhythmia, is needed to prevent sudden death in patients suffering left ventricular dysfunction in the setting of Kawasaki disease.

A Rare Noncardiac Cause for Acute Myocardial Infarction in a 13-Year-Old Patient

A case of ST-segment elevation myocardial infarction in an adolescent patient is presented. The patient presented with resting angina and echocardiographic evidence of wall motion abnormalities in the inferior and posterior segments. The patient was known to have metastatic hepatocellular carcinoma. Tumor was seen in the left inferior pulmonary vein and is proposed to be the source of embolism-causing myocardial infarction. Secondary to intracranial metastatic lesions, the patient was treated conservatively with opiates, nitrates, and beta-blockers. This case is an opportunity to review the causes and management of myocardial infraction in pediatric patients and represents a rare cause of embolic myocardial infraction.

Anomalous Left Coronary Artery from the Pulmonary Artery

Anomalous origin of the left coronary artery from the pulmonary trunk (Bland-Garland-White syndrome) is an important congenital malformation of the coronary circulation.The anomaly occurs in ap proximately 1 in 300,000 live births.Only 10% to 15% of affected infants will reach adulthood.The usual clinical presentation is that of the infant who sustains a myocardial infarction and develops congestive heart failure.Older children or adults can present with a continuous murmur and/or mitral regurgitation resulting from dysfunction of the ischemic papillary muscle.In some cases, the coronary anomaly is unsuspected until a previously well adolescent or adult experiences chest pain, heart failure, or sudden death.

Cardiac damage in pediatric carbon monoxide poisoning

BACKGROUND

Cardiovascular disorders including myocardial ischemia and heart failure have been described in both laboratory animals and humans following carbon monoxide poisoning. Carbon monoxide cardiotoxicity may be clinically occult and often remains undiagnosed because of the lack of overt symptoms and specific ischemic changes in the electrocardiogram. Routine myocardial necrosis markers have low diagnostic efficiency, particularly in patients with concomitant skeletal muscle necrosis or multiple organ failure complicating carbon monoxide poisoning. Carbon monoxide-induced cardiotoxicity has been investigated rarely in children.

CASE REPORT

This paper describes carbon monoxide poisoning in a 12-year-old child who suffered from occult cardiac damage despite mild symptoms and low carboxy hemoglobin concentrations. Myocardial and mitral valve dysfunctions were observed, suggesting an ischemia-like syndrome. Cardiac damage was completely reversible within 1 month.

CONCLUSION

This case report supports that a prolonged carbon monoxide exposure can cause cardiac damage in children even in the absence of specific symptoms, cerebral failure and high carboxyhemoglobin concentrations.

Prolonged myocardial hibernation exacerbates cardiomyocyte degeneration and impairs recovery of function after revascularization

OBJECTIVES

We sought to define the effects of time on contractile function, morphology and functional recovery after coronary revascularization in patients with dysfunctional but viable (hibernating) myocardium.

BACKGROUND

Functional recovery after coronary artery bypass graft surgery in patients with chronic myocardial hibernation is incomplete or delayed. The proposed cause is a progressive temporal degeneration of cardiomyocytes.

METHODS

In 32 patients with multivessel coronary disease, regional wall motion analysis was performed in hypoperfused but metabolically active areas before and 6 months after bypass surgery. During bypass surgery, transmural biopsy samples were obtained from the center of the hypokinetic zone for light and electron microscopic analyses. The proposed duration of myocardial hibernation was retrospectively assessed.

RESULTS

Patients with a subacute hibernating condition (<50 days) demonstrated a higher preoperative ejection fraction (EF, 50+/-8%), and a better preserved wall motion (WM) in the supraapical wall (-1.4+/-0.4) than did patients with intermediate-term (>50 days, EF 37+/-9%, p < 0.05; WM -2.4+/-1.5, p = 0.08) or chronic (>6 months, EF 40+/-14%, WM -2.7+/-0.9, p < 0.005) ischemia. Structural degeneration correlated with the duration of ischemia (r = 0.56, p < 0.05). Postoperative recovery of function was enhanced in patients with a short history of hibernation compared with patients with an intermediate-term or chronic condition (EF 60+/-10% vs. 40+/-10%, p < 0.001, and vs. 47+/-14%, p < 0.05).

CONCLUSIONS

Hibernating myocardium exhibits time-dependent deterioration due to progressive structural degeneration with enhanced fibrosis. Early revascularization should be attempted to salvage the jeopardized tissue and improve postoperative outcome.

Hemopericardium and cardiac tamponade as presenting findings of anomalous left coronary artery syndrome complicated by transmural myocardial infarction

Anomalous origin of the left coronary artery from the pulmonary artery most commonly presents in infancy with clinical features of dilated cardiomyopathy, congestive heart failure or cardiogenic shock as a result of myocardial ischemia. We report the first presentation of this disorder with hemorrhagic pericardial effusion and cardiac tamponade as a result of a transmural myocardial infarction. The list of other causes of hemorrhagic pericardial effusion must now include anomalous left coronary artery syndrome.

Postinfarction ventricular arrhythmias in children

Because limited information is available on significant arrhythmias after myocardial infarction in pediatric patients, this study was performed to determine the incidence and impact of ventricular tachycardia or fibrillation on the postinfarction course in patients aged 1 day to 16 years. Review of 96 such children showed a wide range of underlying heart disease (56 patients with congenital heart disease, 12 with cardiomyopathy, and 28 with acquired heart disease). Postinfarction ventricular tachycardia/fibrillation occurred commonly (28% of patients with acute myocardial infarction) and early (84% by 2 days after diagnosis). Postinfarction mortality was high in patients with acute myocardial infarction (61%) and appeared to be independent of type of associated heart disease. Ventricular tachycardia/fibrillation was associated with higher mortality rates (approximately 80%) in patients with acute or remote myocardial infarction. The 61 postinfarction survivors were monitored for an average of 4.9 years, and none had significant recurrent ventricular arrhythmias or late sudden death.