Patient characteristics and outcomes of acute myocardial infarction presenting without ischemic pain: Insights from the Atherosclerosis Risk in Communities Study.

Background: Our objective was to describe characteristics of patients presenting with and without ischemic pain among those diagnosed with acute myocardial infarction (MI) using individual-level data from the Atherosclerosis Risk in Communities Study from 2005 to 2019. Methods: Acute MI included events deemed definite or probable MI by a physician panel based on ischemic pain, cardiac biomarkers, and ECG evidence. Patient characteristics included age at hospitalization, sex, race/ethnicity, comorbidities (smoking status, diabetes, hypertension, history of previous stroke, MI, or cardiovascular procedure, and history of valvular disease or cardiomyopathy) and in-hospital complications occurring during the event of interest (pulmonary edema, pulmonary embolism, in-hospital stroke, pneumonia, cardiogenic shock, ventricular fibrillation). Analyses were stratified by MI subtype (STEMI, NSTEMI, Unclassified) and patient characteristics and 28-day case fatality was compared between MI presenting with or without ischemic pain. Results: Between 2005 and 2019, there were 1711 hospitalized definite/probable MI events (47 % female, 26 % black, and age of 78 [6.7 years]). A smaller proportion of STEMI patients presented without ischemic pain compared to NSTEMI patients (20 % vs 32 %). Race, sex, age, and comorbidity profiles did not differ significantly across ischemic pain presentations. Patients presenting without ischemic pain had a higher 28-day all-cause case fatality after adjusting for age, race, sex, and comorbidities. However, after further adjustment, time from symptom onset to hospital arrival, time to treatment, and in-hospital complications explained the difference in 28-day case fatality between ischemic pain presentations. Conclusions: Future research should focus on differences in treatment delay across ischemic pain presentations rather than sex differences in acute coronary syndrome presentation.

Harmonic optical microfiber Bragg grating immunosensor for the accelerative test of cardiac biomarker (cTn-I).

Fiber-optic biosensor has shown tremendous promise in probing cardiac biomarkers label-free and in-operando. However, temperature cross-sensitivity is ubiquitously found and impedes further advances of the fiber-optic biosensors, especially for the scenario of rapid test at-body. In this study, we exploit a new regime that harnesses the harmonic resonances of a single microfiber Bragg grating to rule out the impact of the thermal noise. The reflections yielded by the harmonics can be engineered simultaneously at the two overriding optical wavebands, i.e., 1 µm and 1.55 µm, promising a remote acquisition of the sensing signals at patient by virtue of the Yb and/or Er-doped fiber amplifiers which are highly commercial. Furthermore, the functionality of the temperature-offset allows for the understanding of the biomolecular stimulating at the body temperature and thus facilitating the acceleration of the cardiac biomarker test. The proposed proof-of-concept enriches the arsenal of tools for fiber biosensors and enables a vista for the instant and in-vivo diagnosis of acute heart diseases.

Acute Isolated Right Ventricular Infarction: Unusual Presentation of Anterior ST-Segment-Elevation Myocardial Infarction.

Acute right ventricular infarction presenting with ST-segment elevation in the anterior precordial electrocardiographic leads is an unusual event. Anterior ST-segment elevation typically suggests occlusion of the left anterior descending coronary artery. It should be recognized, however, that occlusion of a right coronary artery branch can cause isolated ST-segment elevation in leads V1 and V2 on a standard 12-lead electrocardiogram. We describe the cases of 2 patients who presented with acute chest syndrome with isolated ST-segment elevation in leads V1 and V2. Emergency coronary angiograms revealed that acute thrombotic occlusion of the right ventricular marginal branch of the dominant right coronary artery caused the clinical manifestations in the first patient, whereas occlusion of the proximal nondominant right coronary artery was the culprit lesion in the second patient. Both lesions caused right ventricular myocardial infarction. The patients underwent successful primary percutaneous coronary intervention. These cases illustrate the importance of carefully reviewing angiographic findings to accurately diagnose an acute isolated right ventricular myocardial infarction, which may mimic the electrocardiographic features of an anterior-wall myocardial infarction.

Rotura miocárdica de ventrículo izquierdo secundaria a infarto agudo de miocardio / Myocardial rupture of left ventricle secondary to myocardial infarction

RESUMEN Fundamento: la rotura miocárdica es una complicación rara del infarto agudo de miocardio con una incidencia global de alrededor del 6,2 %. Objetivo: caracterizar los fallecidos por infarto agudo de miocardio con la rotura de pared de ventrículo izquierdo. Métodos: se realizó un estudio retrospectivo, descriptivo y observacional, en el cual se analizaron los fallecidos con diagnóstico de causa directa de muerte: taponamiento cardíaco por hemopericardio, rotura de miocardio e infarto agudo de miocardio. Resultados: de 877 infartos agudos de miocardio diagnosticados entre 2010 a 2018, 16 de ellos presentaron rotura de pared miocárdica de los cuales 68,8 % eran del masculino. El hábito de fumar fue el factor de riesgo predominante. Solo en un 35,7 % se realizó el diagnóstico clínico correcto de IAM y en ninguno de los casos fue planteado el diagnóstico de rotura de miocardio o taponamiento cardíaco por hemopericardio. La región anatómica del corazón donde con mayor frecuencia se localizaron las roturas de miocardio fue en la pared posterior. Conclusiones: la rotura de la pared de miocardio es una complicación del infarto poco frecuente pero catastrófica con una mortalidad elevada, sin embargo, esta puede reducirse si el cuadro clínico es sospechado, y se realiza un diagnóstico precoz con instauración de medidas de apoyo para mantener la estabilidad hemodinámica.

ABSTRACT Background: myocardial rupture is a rare complication of acute myocardial infarction with an overall incidence of around 6.2 %. Objective: to characterize the deaths due to acute myocardial infarction with the rupture of the left ventricle wall. Methods: a retrospective, descriptive and observational study was carried out in which the deceased were analyzed with a diagnosis of direct cause of death: cardiac tamponade due to hemopericardium, myocardial rupture and acute myocardial infarction. Results: of 877 acute myocardial infarcts diagnosed between 2010 and 2018, 16 of them had myocardial wall rupture of which 68.8% were male. The habit of smoking was the predominant risk factor. Only in 35.7 % the correct clinical diagnosis of AMI was made and in none of the cases was the diagnosis of myocardial rupture or cardiac tamponade due to hemopericardium. The anatomical region of the heart where myocardial ruptures were most frequently located was in the posterior wall. Conclusions: rupture of the myocardial wall is a rare but catastrophic complication of infarction with a high mortality, however, this can be reduced if the clinical picture is suspected, and an early diagnosis is made with the introduction of support measures to maintain hemodynamic stability.

Proximal RCA occlusion producing anterior ST segment elevation, Q waves, and T wave inversion.

An ST segment elevation myocardial infarction (STEMI) that produces anterior ST segment elevation (STE) is typically caused by acute occlusion of the left anterior descending (LAD) artery. Anterior STE, however, may also be caused by acute occlusion of either the proximal right coronary artery (RCA) or the right ventricular marginal branch (RVB). It has been thought that, in contrast to occlusions of the LAD, proximal RCA/RVB occlusion rarely causes Q waves in the right precordial leads. We present a case where a proximal RCA occlusion produced not only anterior STE, but also anterior T wave inversions and anterior Q waves.

A label-free cardiac biomarker immunosensor based on phase-shifted microfiber Bragg grating.

Fiber optics evanescent field based biosensor is an excellent candidate for label-free detection of cardiac biomarkers which is of great importance in rapid, early, and accurate diagnosis of acute myocardial infarction (AMI). In this paper, we report a compact and sensitive cardiac troponin I (cTn-I) immunosensor based on the phase-shifted microfiber Bragg grating probe which is functionalized. The fine reflective signal induced by the phase shift in modulation significantly improves the spectral resolution, enabling the ability of the sensor in perceiving an ultra-small refractive index change due to the specific capture of the cTn-I antigens. In buffer, a log-linear sensing range from 0.1 to 10ng/mL and a limit of detection (LOD) of 0.03ng/mL (predicted to be as low as 10.8pg/mL) are obtained. Furthermore, with good specificity, the sensor can be applied in test of cTn-I in human serum samples. The proposed sensor presents superiorities such as improved integratability and portability, easy fabrication and operation, and intrinsic compatibility to the fiber-optic network, and thus has a promising prospect in "point-of-care" test for cardiac biomarkers and preclinical diagnosis.

Single Derivation Fragmented QRS Can Predict Poor Prognosis in Successfully Revascularized Acute STEMI Patients / O QRS Fragmentado de Derivação Única Pode Predizer Mau Prognóstico em Pacientes STEMI Agudos com Revascularização

Abstract Background: QRS fragmentation (fQRS) is classically defined as the presence of slurred QRS morphology in at least two contiguous leads, and its prognostic importance has been shown in ST elevation myocardial infarction (STEMI). However, no study has investigated the significance of single lead fQRS (sl-fQRS) in surface electrocardiography (ECG). Objectives: To evaluate whether sl-fQRS is as valuable as classical fQRS in patients with acute STEMI who had successful revascularization with primary percutaneous coronary intervention (pPCI). Methods: We included 330 patients with a first STEMI who had been successfully revascularized with pPCI. The patient's electrocardiography was obtained in the first 48 hours, and the patients were divided into three groups according to the absence of fQRS (no-fQRS); fQRS presence in a single lead (sl-fQRS); and ≥2 leads with fQRS (classical fQRS). Results: In-hospital mortality was significantly higher both in patients with sl-fQRS and in patients with ≥ 2 leads with fQRS compared to patients with no-fQRS. In ROC curve analysis, ≥ 1 leads with fQRS yielded a sensitivity of 75% and specificity of 57.4% for the prediction of in-hospital mortality. Multivariate analysis showed that sl-fQRS is an independent predictor of in-hospital mortality (OR: 3.989, 95% CI: 1.237-12.869, p = 0.021). Conclusions: Although the concept of at least two derivations is mentioned for the classical definition of fQRS, our study showed that fQRS in only one lead is also associated with poor outcomes. Therefore, ≥1 leads with fQRS can be useful when describing the patients under high cardiac risk in acute STEMI.

Resumo Fundamento: A fragmentação do QRS (fQRS) é classicamente definida como a presença de morfologia empastada do QRS em pelo menos duas derivações contíguas e sua importância prognóstica tem sido demonstrada no infarto do miocárdio com elevação do ST (STEMI). No entanto, nenhum estudo investigou a significância do fQRS de derivação única (sl-fQRS) no eletrocardiograma (ECG). Objetivos: Avaliar se o sl-fQRS é tão valioso quanto o fQRS clássico em pacientes com STEMI aguda que tiveram sucesso na revascularização com intervenção coronariana percutânea primária (ICPp). Métodos: Incluímos 330 pacientes com um primeiro STEMI que tinham sido revascularizados com sucesso com ICPp. O eletrocardiograma do paciente foi obtido nas primeiras 48 horas, e os pacientes foram divididos em três grupos de acordo com a ausência de fQRS (não-fQRS); presença de fQRS numa única derivação (sl-fQRS); e ≥ 2 derivações com fQRS (fQRS clássico). Resultados: A mortalidade intrahospitalar foi significativamente maior tanto em pacientes com sl-fQRS como em pacientes com ≥ 2 derivações com fQRS em comparação com pacientes com não-fQRS. Na análise da curva ROC, ≥ 1 derivação com fQRS produziu uma sensibilidade de 75% e especificidade de 57,4% para a predição de mortalidade intrahospitalar. A análise multivariada mostrou que sl-fQRS é um preditor independente de mortalidade intrahospitalar (OR: 3,989, IC 95%: 1,237-12,869, p = 0,021). Conclusões: Embora o conceito de pelo menos duas derivações seja mencionado para a definição clássica de fQRS, nosso estudo mostrou que fQRS em apenas uma derivação também está associado com maus resultados. Portanto, ≥ 1 derivação com fQRS pode ser útil ao descrever os pacientes sob risco cardíaco alto em STEMI agudo.

Highly Sensitive and Quick Detection of Acute Myocardial Infarction Biomarkers Using In2O3 Nanoribbon Biosensors Fabricated Using Shadow Masks.

We demonstrate a scalable and facile lithography-free method for fabricating highly uniform and sensitive In2O3 nanoribbon biosensor arrays. Fabrication with shadow masks as the patterning method instead of conventional lithography provides low-cost, time-efficient, and high-throughput In2O3 nanoribbon biosensors without photoresist contamination. Combined with electronic enzyme-linked immunosorbent assay for signal amplification, the In2O3 nanoribbon biosensor arrays are optimized for early, quick, and quantitative detection of cardiac biomarkers in diagnosis of acute myocardial infarction (AMI). Cardiac troponin I (cTnI), creatine kinase MB (CK-MB), and B-type natriuretic peptide (BNP) are commonly associated with heart attack and heart failure and have been selected as the target biomarkers here. Our approach can detect label-free biomarkers for concentrations down to 1 pg/mL (cTnI), 0.1 ng/mL (CK-MB), and 10 pg/mL (BNP), all of which are much lower than clinically relevant cutoff concentrations. The sample collection to result time is only 45 min, and we have further demonstrated the reusability of the sensors. With the demonstrated sensitivity, quick turnaround time, and reusability, the In2O3 nanoribbon biosensors have shown great potential toward clinical tests for early and quick diagnosis of AMI.

Detecting Acute Myocardial Infarction by Diffusion-Weighted versus T2-Weighted Imaging and Myocardial Necrosis Markers.

We used a porcine model of acute myocardial infarction to study the signal evolution of ischemic myocardium on diffusion-weighted magnetic resonance images (DWI). Eight Chinese miniature pigs underwent percutaneous left anterior descending or left circumflex coronary artery occlusion for 90 minutes followed by reperfusion, which induced acute myocardial infarction. We used DWI preprocedurally and hourly for 4 hours postprocedurally. We acquired turbo inversion recovery magnitude T2-weighted images (TIRM T2WI) and late gadolinium enhancement images from the DWI slices. We measured the serum myocardial necrosis markers myoglobin, creatine kinase-MB isoenzyme, and cardiac troponin I at the same time points as the magnetic resonance scanning. We used histochemical staining to confirm injury. All images were analyzed qualitatively. Contrast-to-noise ratio (the contrast between infarcted and healthy myocardium) and relative signal index were used in quantitative image analysis. We found that DWI identified myocardial signal abnormity early (<4 hr) after acute myocardial infarction and identified the infarct-related high signal more often than did TIRM T2WI: 7 of 8 pigs (87.5%) versus 3 of 8 (37.5%) (P=0.046). Quantitative image analysis yielded a significant difference in contrast-to-noise ratio and relative signal index between infarcted and normal myocardium on DWI. However, within 4 hours after infarction, the serologic myocardial injury markers were not significantly positive. We conclude that DWI can be used to detect myocardial signal abnormalities early after acute myocardial infarction-identifying the infarction earlier than TIRM T2WI and widely used clinical serologic biomarkers.

Infarto do ventriculo direito / Right ventricle infarction

O infarto do ventrículo direito (VD) não é entidade clínica rara. É observado em 10 a 50% dos pacientes com infarto da parede inferior do ventrículo esquerdo (VE). Estão agrupados nesse amplo espectro diagnóstico os pacientes com disfunção ventricular leve, assintomáticos e aqueles em choque cardiogênico. O reconhecimento do infarto do VD é importante, porque se associa a mais morbi e mortalidade imediatas, além de apresentar prioridade de tratamento específico. O diagnóstico do infarto do VD é baseado em sinais clínicos, eletrocardiográficos, hemodinâmicos e ecográficos. A abordagem adequada do infarto do VD inclui medidas para manter a pré-carga adequada e reduzir a pós-carga do VD, suporte inotrópico, e manutenção do sincronismo átrio-ventricular. A terapia de reperfusão miocárdica com fibrinolítico ou a angioplastia primária deve ser indicada e iniciada precocemente. A maior parte dos pacientes que sobrevivem ao infarto do VD tem resolução completa das alterações hemodinâmicas com o restabelecimento da função do VD no decorrer de semanas a meses, sugerindo que ?atordoamento? do miocárdio direito, em vez de necrose irreversível, ocorre com mais frequência.

Right ventricle infarction (RVI) is not a rare clinical entity. It complicates 10 to 50% of patients with inferior wall myocardial infarctions. Under the term RVI we can find mild, asymptomatic dysfunction of right ventricle and cardiogenic shock as well. Recognition of the syndrome of RVI is important as it is associated with considerable immediate morbidity and mortality and has a well-delineated set of priorities for its management. Diagnosis is based on clinical signs, electrocardiographic findings, hemodynamic measurements and echographic evaluations. The proper management of RVI includes volume loading to maintain adequate right ventricular preload, ionotropic support, reduction of right ventricular afterload and maintenance of atrioventricular synchrony. Early reperfusion with fibrinolytic therapy or direct angioplasty should be initiated at the earliest signs of right ventricular dysfunction. Most patients who survive RVI have complete resolution of hemodynamic abnormalities with restoration of proper right ventricle function over a period of weeks to months, suggesting right ventricular stunning rather than irreversible necrosis has occurred.

Takayasu arteritis with coronary aneurysms causing acute myocardial infarction in a young man.

Takayasu arteritis is an inflammatory condition that involves the large cardiac vessels, predominantly the aorta and its main branches. It typically affects young women (age, ≤40 yr), most often Asians and Latin Americans. Herein, we describe a rare manifestation of Takayasu arteritis in a 19-year-old black Tunisian man who presented with acute inferior myocardial infarction and complete atrioventricular block after occlusion from a giant aneurysm in the right coronary artery. The coronary artery disease was associated with aneurysmal dilations in the carotid, vertebral, and right renal arteries. Medical therapy improved Thrombolysis in Myocardial Infarction flow in the area of the giant aneurysm from grade 1 to grade 3. Upon the diagnosis of Takayasu arteritis, intravenous methylprednisolone and oral prednisone therapy was started. After 10 days of hospitalization, the patient was discharged on a medical regimen. Renovascular hypertension due to renal artery stenosis was suspected, so he underwent successful percutaneous transluminal angioplasty of the inferior segmental artery of the right renal artery. During 12 months of close postprocedural monitoring, he experienced lower blood pressure, no chest pain, and no cardiovascular complications.This association of conditions has not been previously reported. Besides presenting this very rare combination of findings, we discuss the differential diagnosis of Takayasu arteritis in our patient.

Levofloxacin-induced torsades de pointes.

A 91-year-old woman, presenting with flu-like symptoms, developed a brief episode of polymorphic ventricular tachycardia in the emergency department. The arrhythmia resolved spontaneously, and a subsequent electrocardiogram revealed Q waves and ST-segment elevation in the anterior precordial leads, along with a prolonged QT interval. The presumed diagnosis was ST-segment-elevation myocardial infarction with ischemia-induced ventricular tachycardia. Emergent coronary artery angiography revealed only minimal luminal irregularities. It was discovered that the patient had been taking levofloxacin and, apparently as a result, developed drug-induced torsades de pointes. The case of this patient is an example of the difficulties that are occasionally encountered in differentiating ST-segment-elevation myocardial infarction from nonischemic ST elevation.

Split right coronary artery: its definition and its territory.

We report here, for perhaps the 1st time in the English-language literature, the extent of the territory fed by the anterior bifurcation of the (anomalous) split right coronary artery (RCA). A 64-year-old man presented with an occlusion of the anterior bifurcation of a split RCA--which resulted in an infarct that involved both the inferoseptal left ventricular wall and the anterior right ventricular free wall. Split RCA is the same anomaly as the improperly named "double right coronary artery." In reality, there are not 2 RCAs, but only split portions of the posterior descending branch of the RCA, with 2 separate proximal courses.

Use of gallium 67 scintigraphy to differentiate acute myocarditis from acute myocardial infarction.

This study was designed to evaluate the role and effectiveness of gallium 67 imaging in the diagnosis of acute myocarditis that mimics acute myocardial infarction. Of 315 consecutive acute myocardial infarction patients admitted to our institution over a 4-year period, 5 (2 men, 3 women) were suspected of having acute myocarditis. These 5 patients ranged in age from 23 to 69 years (median, 32 yr). All had experienced diarrhea or flu-like symptoms within the preceding 4 weeks, and each presented with signs, symptoms, and electrocardiographic findings consistent with acute myocardial infarction. Echocardiography revealed decreased left ventricular systolic function. Gallium 67 myocardial scintigraphy was performed in 4 patients, 72 hours after intravenous injection of 9 mCi of gallium citrate Ga 67, and sooner than that in one. In all 5 patients, the results were positive, consistent with a diagnosis of acute myocarditis. One patient died of progressive heart failure 4 days after admission. Within 1 month of beginning medical therapy, the 4 surviving patients experienced resolution of abnormal ventricular function and symptoms. During a median follow-up period of 64 months, no cardiovascular events were observed, and the prognoses were deemed excellent. We suggest that gallium 67 scintigraphy is a useful method by which to identify acute myocarditis in patients in whom the condition is suspected. To our knowledge, this is the 1st report of the use of gallium 67 myocardial scanning to differentiate acute myocarditis from acute myocardial infarction.

THE DIAGNOSTIC VALUE OF SERUM PYRUVATE KINASE IN ACUTE MYOCARDIAL INFARCTION / 解放军医学杂志

The activities of serum PK of 51 cases with AMI were determined. It was raised in all of the 43 cases with AMI within 24h after admission. Serum PK was specific for the early diagnosis of AMI