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Background Fractional flow reverse (FFR) is the gold standard assessment of the hemodynamic significance of coronary stenoses. However, it requires the catheterization of the coronary artery to determine the pressure waveforms proximal and distal to the stenosis. On the contrary, computational fluid dynamics enables the calculation of the FFR value from relatively non-invasive computed tomography angiography (CTA). Methods We analyze the flow across idealized highly-eccentric coronary stenoses by solving the Navier–Stokes equations. We examine the influence of several aspects (approximations) of the simulation method on the calculation of the FFR value. We study the effects on the FFR value of errors made in the segmentation of clinical images. For this purpose, we compare the FFR value for the nominal geometry with that calculated for other shapes that slightly deviate from that geometry. This analysis is conducted for a range of stenosis severities and different inlet velocity and pressure waveforms. Results and conclusions The errors made in assuming a uniform velocity profile in front of the stenosis, as well as those due to the Newtonian and laminar approximations, are negligible for stenosis severities leading to FFR values around the threshold 0.8. The limited resolution of the stenosis geometry reconstruction is the major source of error when predicting the FFR value. Both systematic errors in the contour detection of just 1-pixel size in the CTA images and a low-quality representation of the stenosis surface (coarse faceted geometry) may yield wrong outcomes of the FFR assessment for an important set of eccentric stenoses. On the contrary, the spatial resolution of images acquired with optical coherence tomography may be sufficient to ensure accurate predictions for the FFR value.

Resumen Fundamentos y objetivo El sindrome de Tako-tsubo (SmT) es una miocardiopatia aguda reversible que simula un infarto. Analizamos los 60 pacientes ingresados con SmT en nuestro centro. Pacientes y metodo El 73,3% eran mujeres (edad media [DE] de 70,6 [8,11] anos). El 83,3% tenia algun factor de riesgo cardiovascular, el 25% tenia trastorno ansiosodepresivo y en el 58,3% se identifico algun desencadenante, siendo el estres emocional el mas frecuente. El 15,3% mostro bloqueo completo de rama izquierda (BCRI). En el 23,3% las alteraciones de la contractilidad respetaban el apex (formas medioventriculares o diafragmaticas). Resultados La arteria descendente anterior mostro lesiones no significativas en el 35% de los pacientes, y en el 68,3% tenia trayecto diafragmatico. El 40% desarrollo insuficiencia cardiaca (ICC) y el 18,3% shock cardiogenico (SC). La mortalidad hospitalaria global fue del 3,3%, siendo del 8,3% entre aquellos que desarrollaron ICC. La incidencia de SC fue mayor entre los pacientes con BCRI (44,4 frente a 13,7%; p = 0,05) y los varones (43,8 frente a 9,1%; p = 0,005). Conclusiones Aunque la mortalidad hospitalaria del SmT es baja, un porcentaje importante de pacientes desarrollan ICC, siendo la mortalidad de este subgrupo elevada. Los pacientes varones y aquellos con BCRI presentaron mayor morbilidad hospitalaria.

We present a case of a 52 year old female who suffered from a sudden syncope. A coronariography was performed and spontaneous coronary dissection was diagnosed in the posterior descending artery after an optical coherence tomography (OCT) was performed. A conservative management was decided. During hospitalization the patient presented with an episode of chest pain with an anterior ST elevation on ECG. Coronariography showed total occlusion of the left descending artery and again a dissection was diagnosed by OCT. This time, 2 stents were implanted in the affected artery. The hypothesis that the coronary adventitial volume of vasa vasorum is higher in patients with spontaneous coronary artery dissection has been demonstrated in a recent small study and it was observed in this patient. Conservative management is preferred in most cases, proceeding to revascularization for patients with ongoing chest pain, hemodynamic instability and ST elevation, mostly if it affects major arteries.

The Tako-tsubo syndrome (TS) is a reversible acute cardiomyopathy simulating an infarction. We analyzed 60 patients admitted with TS in our center.A percentage of 73.3 were women (mean age: 70.6 ± 11.8 years); 83.3% had some cardiovascular risk factor, 25% had an anxiety-depressive disorder and in 58.3% a precipitating factor was identified, emotional stress being the most frequent. A percentage of 15.3 showed complete left bundle branch block (LBBB). In 23.3% of patients, contractile abnormalities respected the apex (mid ventricular or diaphragmatic types).The anterior descending artery showed no significant lesions in 35% of patients and in 68.3% it had a diaphragmatic segment. Forty percent of patients developed heart failure (HF) and 18.3% cardiogenic shock (CS). The overall in-hospital mortality was 3.3%, while it was 8.3% among those patients who developed HF. The incidence of CS was higher among patients with LBBB (44.4 vs. 13.7%, P=.05) and males (43.8 vs. 9.1%, P=.005).Although in-hospital mortality in patients admitted due to TS is low, a significant percentage of these patients develop HF with a high mortality in this subgroup. Males and patients with LBBB had higher in-hospital morbidity.