Myocardial Rupture in Acute Myocardial Infarction: Mechanistic Explanation Based on the Ventricular Myocardial Band Hypothesis.

BACKGROUND: Torrent-Guasp explains the structure of the ventricular myocardium by means of a helical muscular band. Our primary purpose was to demonstrate the utility of echocardiography in human and porcine hearts in identifying the segments of the myocardial band. The second purpose was to evaluate the relation of the topographic distribution of the myocardial band with some post-myocardial infarction ruptures. METHODS: Five porcine and one human heart without cardiopathy were dissected and the ventricular myocardial segments were color-coded for illustration and reconstruction purposes. These segments were then correlated to the conventional echocardiographic images. Afterwards in three cases with post-myocardial infarction rupture, a correlation of the topographic location of the rupture with the distribution of the ventricular band was made. RESULTS: The human ventricular band does not show any differences from the porcine band, which confirms the similarities of the four segments; these segments could be identified by echocardiography. In three cases with myocardial rupture, a correlation of the intra-myocardial dissection with the distribution of the ventricular band was observed. CONCLUSIONS: Echocardiography is helpful in identifying the myocardial band segments as well as the correlation with the topographic distribution of some myocardial post-infarction ruptures.

Intramyocardial hemorrhage in spontaneously reperfused myocardial infarction.

OBJECTIVE. The presence of intramyocardial hemorrhage (IMH) is frequent in patients with acute myocardial infarction (AMI) undergoing primary percutaneous coronary intervention (PPCI). We aim for the presence IMH using cMRI in patients who presented AMI and did not undergo PPCI or thrombolysis. Cardiac magnetic resonance has proven to be a highly sensitive method for detect its presence in the ischemic damaged tissue. MATERIAL AND METHODS. Patients admitted with diagnosis of ST elevation myocardial infarction > 24 h after initial presentation and without reperfusion therapy were enrolled in the study. All patients underwent cardiac magnetic resonance for detecting edema, microvascular obstruction and intramyocardial hemorrhage, followed by coronary angiography. RESULTS. Seven male patients, with median age of 53 years, were enrolled. Cardiac magnetic resonance showed that all patients had microvascular obstruction and edema. Two of them had intramyocardial hemorrhage in association with spontaneous reperfusion demonstrated by angiography. CONCLUSION. The results of our study show that in patients with acute myocardial infarction, intramyocardial hemorrhage occurs not only after therapeutic, but also after spontaneous reperfusion. This is the first time that its presence is demonstrated by cardiac magnetic resonance.

Impaired Ischemia-Reperfusion Responses in the Hearts of Aged Male and Female Offspring of Obese Rats.

Maternal obesity predisposes offspring (F1) to cardiovascular disease. To evaluate basal heart function and ischemia-reperfusion (IR) responses in F1 males and females of obese mothers, female Wistar rats (F0) were fed chow or an obesogenic (MO) diet from weaning through pregnancy and lactation. Non-sibling F1 males and females were weaned to chow at postnatal day (PND) 21 and euthanized at PND 550. Offspring of MO mothers (MOF1) rarely survive beyond PND 650. Hearts were immediately isolated from euthanized F1s and subjected to 30 min ischemia with 20 min reperfusion. Retroperitoneal fat, serum triglycerides, glucose, insulin, and insulin resistance were measured. Baseline left ventricular developed pressure (LVDP) was lower in male and female MOF1 than in controls. After global ischemia, LVDP in control (C) male and female F1 recovered 78 and 83%, respectively, while recovery in MO male and female F1 was significantly lower at 28 and 52%, respectively. Following the IR challenge, MO hearts showed a higher functional susceptibility to reperfusion injury, resulting in lower cardiac reserve than controls in both sexes. Female hearts were more resistant to IR. Retroperitoneal fat was increased in male MOF1 vs. CF1. Circulating triglycerides and insulin resistance were increased in male and female MOF1 vs. CF1. These data show that MO programming reduces F1 cardiac reserve associated with age-related insulin resistance in a sex-specific manner.

Postconditioning protects against reperfusion injury in hypertensive dilated cardiomyopathy by activating MEK/ERK1/2 signaling.

BACKGROUND: Postconditioning (PostC) cardioprotection has been related to up-regulation of survival kinases; however, the efficacy of PostC and the role of ERK1/2 (extracellular signal-regulated kinase 1/2) remain to be substantiated in hypertension states that may produce "pathologic remodeling." Therefore, in this work we compared PostC effect and assessed the role of ERK1/2 activation in a model of hypertensive dilated cardiomyopathy (DCM), versus normal (Sham) and compensated hypertrophy (CH) models. METHODS AND RESULTS: Rats were subjected to angiotensin II administration until development of cardiovascular diseases. Then, isolated hearts underwent ischemia followed by PostC and reperfusion. PostC maintained the double product in all groups. PostC reduced infarct size from 36.16 ± 3% to 9.8% ± 2.2 in Sham, from 37.5 ± 2.4% to 12 ± 3% in CH, and from 40 ± 2.4% to 11.55 ± 3% in DCM. Inhibition of the mitogen-activated protein kinase kinase (MEK)/ERK1/2 pathway had different effects on PostC-conferred cardioprotection in the evaluated groups. Interestingly, although phosphatidylinositol-3-kinase activation was negligible in PostC DCM hearts, we observed Akt activation. CONCLUSIONS: PostC confers cardioprotection through alternative survival pathways in normal and CH hearts, and cardiac function recovery in DCM relies mainly on MEK/ERK1/2 cascade. Down-regulation of phosphatidylinositide 3-kinase does not affect the cardioprotective response in DCM, because MEK/ERK1/2 cascade may convey direct Akt activation, strengthening downstream signaling.

Intramyocardial dissecting hematoma and postinfarction cardiac rupture.

Potentially fatal cardiac rupture is a complication of myocardial infarction (MI), which can appear in the first hours of the acute event and during the course of the first week. The intramyocardial dissecting hematoma might appear as a component of the rupture during the evolution process. The description of the myocardium as a helical muscular band facilitates the explanation of the fiber dissection. With echocardiography, it is possible to diagnose intramyocardial dissecting hematomas (IDH), determine its location, progression, potential complications, and in some cases its reabsorption. It is necessary to search for neocavitations in the infarcted myocardium and identify the intramyocardial edge that surrounds the defect, as well as the flow inside the myocardial dissection, the pathway of the dissection, and its communication with ventricular cavities, and also to look for the complete or partial reabsorption of the cavitary image. The greater the myocardial dissection is, the worse the prognosis. If the dissecting hematoma is confined to the apical segments, it is more likely to reabsorb spontaneously. Tissue characterization with magnetic resonance during an acute myocardial infarction allows identification of reperfusion injuries with altered microcirculation and intramyocardial hemorrhage (IMH). It is necessary to search for IMH in reperfused patients with ventricular arrhythmias, stunned myocardium, and no reflow. These patients may develop an increased stiffness in the infarcted wall and a major likelihood to develop a parietal rupture. Everything seems to indicate that we are facing the same physiopathological process which can be characterized by 2 complementary imaging methods, echocardiography and magnetic resonance.

NAC Pre-Administration Prevents Cardiac Mitochondrial Bioenergetics, Dynamics, Biogenesis, and Redox Alteration in Folic Acid-AKI-Induced Cardio-Renal Syndrome Type 3.

The incidence of kidney disease is increasing worldwide. Acute kidney injury (AKI) can strongly favor cardio-renal syndrome (CRS) type 3 development. However, the mechanism involved in CRS development is not entirely understood. In this sense, mitochondrial impairment in both organs has become a central axis in CRS physiopathology. This study aimed to elucidate the molecular mechanisms associated with cardiac mitochondrial impairment and its role in CRS development in the folic acid-induced AKI (FA-AKI) model. Our results showed that 48 h after FA-AKI, the administration of N-acetyl-cysteine (NAC), a mitochondrial glutathione regulator, prevented the early increase in inflammatory and cell death markers and oxidative stress in the heart. This was associated with the ability of NAC to protect heart mitochondrial bioenergetics, principally oxidative phosphorylation (OXPHOS) and membrane potential, through complex I activity and the preservation of glutathione balance, thus preventing mitochondrial dynamics shifting to fission and the decreases in mitochondrial biogenesis and mass. Our data show, for the first time, that mitochondrial bioenergetics impairment plays a critical role in the mechanism that leads to heart damage. Furthermore, NAC heart mitochondrial preservation during an AKI event can be a valuable strategy to prevent CRS type 3 development.

Osthole Prevents Heart Damage Induced by Diet-Induced Metabolic Syndrome: Role of Fructokinase (KHK).

There is increasing evidence that either ingested or produced fructose may have a role in metabolic syndrome. While not commonly considered a criterion for metabolic syndrome, cardiac hypertrophy is often associated with metabolic syndrome, and its presence carries increased cardiovascular risk. Recently it has been shown that fructose and fructokinase C (KHK) can be induced in cardiac tissue. Here we tested whether diet-induced metabolic syndrome causes heart disease associated with increased fructose content and metabolism and whether it can be prevented with a fructokinase inhibitor (osthole). Male Wistar rats were provided a control diet (C) or high fat/sugar diet for 30 days (MS), with half of the latter group receiving osthol (MS+OT, 40 mg/kg/d). The Western diet increased fructose, uric acid, and triglyceride concentrations in cardiac tissue associated with cardiac hypertrophy, local hypoxia, oxidative stress, and increased activity and expression of KHK in cardiac tissue. Osthole reversed these effects. We conclude that the cardiac changes in metabolic syndrome involve increased fructose content and its metabolism and that blocking fructokinase can provide cardiac benefit through the inhibition of KHK with modulation of hypoxia, oxidative stress, hypertrophy, and fibrosis.

Unilateral Ureteral Obstruction for 28 Days in Rats Is Not Associated with Changes in Cardiac Function or Alterations in Mitochondrial Function.

Our work evaluated cardiac function and mitochondrial bioenergetics parameters in hearts from male Wistar rats subjected to the UUO model during 28 days of progression. We measured markers of kidney damage and inflammation in plasma and renal fibrosis by histological analysis and Western blot. Cardiac function was evaluated by echocardiography and proteins involved in cardiac damage by Western blot. Oxygen consumption and transmembrane potential were monitored in cardiac mitochondria using high-resolution respirometry. We also determined the activity of ATP synthase and antioxidant enzymes such as glutathione peroxidase, glutathione reductase, and catalase. Our results show that, although renal dysfunction is established in animals subjected to ureteral obstruction, cardiac function is maintained along with mitochondrial function and antioxidant enzymes activity after 28 days of injury evolution. Our results suggest that renocardiac syndrome might develop but belatedly in obstruction-induced renal damage, opening the opportunity for treatment to prevent this condition.

The role of left atrial enlargement and age in the prediction of recurrence in embolic strokes of undetermined source.

Objectives: Left atrial disease is an independent risk factor for ischemic stroke and can be used to predict atrial fibrillation (AF). We examine whether left atrial enlargement (LAE) could predict stroke recurrence in patients with embolic stroke of undetermined source (ESUS). Materials and methods: Sixty-four patients with a confirmed diagnosis of ESUS were followed for a median of 22 months. Clinical data and echocardiogram findings were recorded. The echocardiogram interpretation was performed centrally and blindly. The Brown ESUS - AF score was used to categorize patients into high (human resource planning [HRP]: score > 2) and low-risk patients (non-HRP score 0-1). Stroke recurrence was the primary outcome. Results: The median age was 62 years (range: 22-85 years); and 33 (51.6%) were men. The median initial NIHSS score was three points (range: 0-27). Twelve (18.8%) patients were categorized as HRP. We found a significant tendency toward recurrence among HRP versus non-HRP patients. Three (25%) HRP versus 2 (3.8%) non-HRP experienced recurrence (OR: 8.3 95% CI 1.2-57; p=0.042); this association was related to severe atrial dilatation (OR: 14.5 95% CI 0.78-277, p = 0.02) and age > 75 years (OR: 12.7 95% CI 1.7-92.2, p = 0.03). We found no differences in recurrence in a univariate analysis. Conclusions: Patients with severe LAE who are 75 years old or older have a significant tendency to experience stroke recurrence.

Objetivos: La patología atrial izquierda es factor de riesgo independiente para infarto cerebral y puede utilizarse para predecir fibrilación auricular. Examinamos si el crecimiento aurícular izquierdo puede predecir recurrencia en pacientes con infarto embolico de origen indeterminado (ESUS). Materiales y métodos: Sesenta y cuatro pacientes con diagnóstico confirmado de ESUS fueron seguidos por una mediana de seguimiento de 22 meses. Registramos los datos clínicos y ecocardiográficos. La interpretación ecocardiográfica fue centralizada y cegada. La escala de Brown ESUS ­ AF fue utilizada para categorizar a los pacientes en riesgo alto (HRP puntaje > 2) y bajo riesgo (no-HRP: puntaje 0-1). El descenlace primario fue recurrencia de infarto cerebral. Resultados: Mediana de edad fue de 62 años (rango: 22-85 años); 33 (51.6%) fueron hombres. La mediana inicial de la escala de NIHSS fue de 3 putnos (rango de 0 a 27). 12 (18.8%) pacientes fueron de alto riesgo (HRP) y 52 (81.3%) de bajo riesgo (non- HRP). El grupo HRP mostró tendencia significatica hacia mayor recurrencia. Tres (25%) HRP versus 2 (3.8%) no-HRP experimentaron recurrencia (OR: 8.3 IC 95% 1.2-57; p = 0.042); esta asociación se relacionó con dilatación auricular severa (OR: 14.5 IC 95% 0.78-277, p = 0.02) y edad > 75 años (OR: 12.7 IC 95% 1.7-92.2, p = 0.03). En el análisis multivarioado, no encontramos significativas. Conclusiones: El crecimiento auricular izquierdo severo y la edad mayor de 75 años mostraron tendencia significativa a recurrencia de infarto cerebral.

Echocardiographic Findings in Canine Model of Chagas Disease Immunized with DNA Trypanosoma cruzi Genes.

Chagas disease (ChD) is considered an emerging disease in the USA and Europe. Trypanosoma cruzi genes encoding a trans-sialidase protein and an amastigote-specific glycoprotein were tested as vaccines in canine model. The aim for this study was determining the prophylactic effect of these genes in experimentally infected dogs by echocardiography evaluation to compare with our findings obtained by other techniques published previously. Low fractional-shortening values of non-vaccinated dogs suggested an impairment in general cardiac function. Low left ventricular ejection fraction values found in infected dogs suggested myocardial injury regardless of whether they were vaccinated. Low left ventricular diastolic/systolic diameters suggested that progressive heart damage or heart dilation could be prevented by DNA vaccination. Systolic peak time was higher in non-vaccinated groups, increasing vulnerability to malignant arrhythmias and sudden death. High left ventricular volume suggested a decrease in wall thickness that might lead to increased size of the heart cavity, except in the pBCSP plasmid-vaccinated dogs. There was an echocardiographic evidence of left ventricular dilation and reduction in systolic function in experimental chagasic dogs. Echocardiography allowed a more complete follow-up of the pathological process in the living patient than with other techniques like electrocardiography, anatomopathology, and histopathology, being the method of choice for characterizing the clinical stages of ChD.

DNA Vaccine Treatment in Dogs Experimentally Infected with Trypanosoma cruzi.

Chagas disease is a chronic and potentially lethal disorder caused by the parasite Trypanosoma cruzi, and an effective treatment has not been developed for chronic Chagas disease. The objective of this study was to determine the effectiveness of a therapeutic DNA vaccine containing T. cruzi genes in dogs with experimentally induced Chagas disease through clinical, pathological, and immunological analyses. Infection of Beagle dogs with the H8 T. cruzi strain was performed intraperitoneally with 3500 metacyclic trypomastigotes/kg body weight. Two weeks after infection, plasmid DNA immunotherapy was administered thrice at 15-day intervals. The clinical (physical and cabinet studies), immunological (antibody and cytokine profiles and lymphoproliferation), and macro- and microscopic pathological findings were described. A significant increase in IgG and cell proliferation was recorded after immunotherapy, and the highest stimulation index (3.02) was observed in dogs treated with the pBCSSP4 plasmid. The second treatment with both plasmids induced an increase in IL-1, and the third treatment with the pBCSSP4 plasmid induced an increase in IL-6. The pBCSP plasmid had a good Th1 response regulated by high levels of IFN-gamma and TNF-alpha, whereas the combination of the two plasmids did not have a synergistic effect. Electrocardiographic studies registered lower abnormalities and the lowest number of individuals with abnormalities in each group treated with the therapeutic vaccine. Echocardiograms showed that the pBCSSP4 plasmid immunotherapy preserved cardiac structure and function to a greater extent and prevented cardiomegaly. The two plasmids alone controlled the infection moderately by a reduction in the inflammatory infiltrates in heart tissue. The immunotherapy was able to reduce the magnitude of cardiac lesions and modulate the cellular immune response; the pBCSP treatment showed a clear Th1 response; and pBCSSP4 induced a balanced Th1/Th2 immune response that prevented severe cardiac involvement. The pBCSSP4 plasmid had a better effect on most of the parameters evaluated in this study; therefore, this plasmid can be considered an optional treatment against Chagas disease in naturally infected dogs.

2D and 3D echocardiography of a left ventricular diverticulum.

A real time transthoracic 3D study of a left ventricular diverticulum established through a narrow orifice located between the aortic and mitral valves is presented. Diverticular morphology was reconstructed and its volumes were calculated by this technique for the first time in the literature.

Dissecting intramyocardial hematoma: clinical presentation, pathophysiology, outcomes and delineation by echocardiography.

BACKGROUND: In large necropsy studies dissecting intramyocardial hematoma (DIH) with serpiginous tracts across the myocardial fibers has been reported in both the septum and the left ventricle free wall. METHODS: We studied 15 patients admitted to the hospital with acute myocardial infarction (AMI) in which DIH was demonstrated by either transthoracic and/or transesophageal and confirmed intraoperatively or by necropsy. RESULTS: In nine patients the hemorrhagic dissection was predominantly in the septum and in the remaining it was in the free wall of the left ventricle (LV). Myocardial infarction involved the left ventricular inferior wall in two, and the anterior wall in 13 patients. The overall mortality was 47%, and in the group with septal hematoma it reached to 78%. Echocardiography disclosed the various acoustic densities of the evolving intramyocardial hematoma, its extension through the hemorrhagic dissection, its spontaneous reabsorption, as well as its communication with the ventricular cavities. CONCLUSIONS: Echocardiography is the method of choice for the noninvasive diagnosis of patients with suspected myocardial rupture and intramyocardial dissection postmyocardial infarction.

Subepicardial aneurysm: echocardiographic evaluation and evolution.

Subepicardial aneurysms (SEA) are an infrequent and serious form of subacute cardiac rupture complicating myocardial infarction. An early diagnosis and surgical repair may be life saving. SEA comprise an abrupt interruption of the myocardium, with a narrow neck and thin wall containing only the epicardium. It may progress to fatal cardiorrhexis. We describe the echocardiographic evolution of this type of cardiac rupture and the contribution of contrast-enhanced echocardiography. A possible pathophysiological mechanism is proposed.

Three-dimensional transesophageal echocardiography of the atrial septal defects.

Transesophageal echocardiography has advantages over transthoracic technique in defining morphology of atrial structures. Even though real time three-dimensional echocardiographic imaging is a reality, the off-line reconstruction technique usually allows to obtain higher spatial resolution images. The purpose of this study was to explore the accuracy of off-line three-dimensional transesophageal echocardiography in a spectrum of atrial septal defects by comparing them with representative anatomic specimens.

[Obstructive hypertrophic cardiomyopathy]. / Miocardiopatía hipertrófica obstructiva.

Hypertrophic cardiomyopathy (HCM) was first described more than a century ago; the characteristic finding is an inappropriate myocardial hypertrophy, occurring in the absence of an obvious cause. Determination of the exact site of the hypertrophy and of the obstruction of the left ventricular outflow tract, in asymmetric septal hypertrophy, establishes which is the best treatment strategy. Forty-one-year-old man with a history of recurrent palpitations without any other symptomatology. The initial electrocardiogram (EKG) showed sinus rhythm with evidence of ventricular left hypertrophy and unspecific changes in ventricular repolarization. The transthoracic echocardiogram showed HCM and mitral regurgitation. The electrophysiological study, under treatment with amiodarone, did not induce ventricular arrhythmias. The 10-years evolution of the EKG showed changes of variable degrees associated with the hypertrophy and systolic overload of the left ventricle. The echocardiographic three-dimensional reconstruction in the long axis revealed the dynamic obstruction of the left ventricular outflow tract. In the hemodynamic study, the existence of a subaortic gradient confirmed the diagnosis and showed an increase of the gradient at the post-extrasystolic beat (Brockenbrough-Braunwald phenomenon). The echocardiographic three-dimensional reconstruction defines more accurately the exact site of the septal hypertrophy and its hemodynamic consequences.

[Echocardiography in valvular heart disease. New perspectives]. / Ecocardiografía: aportaciones en la evaluación del daño valvular: nuevas perspectivas.

Echocardiography occupies an excellent place in the field of valvular heart disease study. Its presence is being increased in the catheterism and surgery rooms as well as in the intensive cares units. The ultrasound machines development has improved its technology and echocardiographic diagnoses has a greater repercussion in clinical decisions every time. The greater challenge than appears to us is to be able to have prepared enough professionals that know the tool, the physiopathology, the therapeutics modalities, and who can apply and take advantage of the new technological developments for a better cardiological practice.

Increased HDL Size and Enhanced Apo A-I Catabolic Rates Are Associated With Doxorubicin-Induced Proteinuria in New Zealand White Rabbits.

The catabolism and structure of high-density lipoproteins (HDL) may be the determining factor of their atheroprotective properties. To better understand the role of the kidney in HDL catabolism, here we characterized HDL subclasses and the catabolic rates of apo A-I in a rabbit model of proteinuria. Proteinuria was induced by intravenous administration of doxorubicin in New Zealand white rabbits (n = 10). HDL size and HDL subclass lipids were assessed by electrophoresis of the isolated lipoproteins. The catabolic rate of HDL-apo A-I was evaluated by exogenous radiolabelling with iodine-131. Doxorubicin induced significant proteinuria after 4 weeks (4.47 ± 0.55 vs. 0.30 ± 0.02 g/L of protein in urine, P < 0.001) associated with increased uremia, creatininemia, and cardiotoxicity. Large HDL2b augmented significantly during proteinuria, whereas small HDL3b and HDL3c decreased compared to basal conditions. HDL2b, HDL2a, and HDL3a subclasses were enriched with triacylglycerols in proteinuric animals as determined by the triacylglycerol-to-phospholipid ratio; the cholesterol content in HDL subclasses remained unchanged. The fractional catabolic rate (FCR) of [(131)I]-apo A-I in the proteinuric rabbits was faster (FCR = 0.036 h(-1)) compared to control rabbits group (FCR = 0.026 h(-1), P < 0.05). Apo E increased and apo A-I decreased in HDL, whereas PON-1 activity increased in proteinuric rabbits. Proteinuria was associated with an increased number of large HDL2b particles and a decreased number of small HDL3b and 3c. Proteinuria was also connected to an alteration in HDL subclass lipids, apolipoprotein content of HDL, high paraoxonase-1 activity, and a rise in the fractional catabolic rate of the [(131)I]-apo A-I.

Risk factors, echocardiographic patterns, and outcomes in patients with acute ventricular septal rupture during myocardial infarction.

Ventricular septal rupture (VSR), which can complicate an acute myocardial infarction (MI), carries a high mortality rate. Because precordial and transesophageal echocardiography can identify the type of rupture and assess right ventricular (RV) function at the patient's bedside, we examined the prognostic significance of echocardiographic patterns in postinfarct VSR by postulating that complex rupture and RV involvement carry a worse prognosis. Seventeen patients (10 men; mean age 66 years) who had confirmed postinfarct VSR underwent precordial and transesophageal echocardiography followed by coronary angiography. Serial 12-lead and right precordial leads were also available. Type of septal rupture was classified as simple or complex based on autopsy-proved echocardiographic criteria. Three patients had inferior wall MI and 14 had anterior wall MI. ST-segment elevation persisted >72 hours in all 3 patients who had inferior wall MI and in 12 who had anterior wall MI. Segmental wall motion abnormalities helped in detecting the left ventricular entry site, and use of unconventional views superimposed with color flow Doppler provided the RV exit site. RV function was better appreciated with transesophageal echocardiography. Two patients who had inferior wall MI and 7 who had anterior wall MI had complex ruptures. All 3 patients who had inferior wall MI and 7 who had anterior wall MI had electrocardiographic and echocardiographic evidence of RV involvement. Mortality rate was higher in patients who had complex rupture (78% vs 38%, p <0.001) and in those who had RV extension (71% vs 29%, p <0.001). In conclusion, persistent ST elevation is a common finding in patients who have postinfarct VSR. Complex VSR and RV involvement are significant determinants of clinical outcome.

[Interaction between microbubbles and ultrasound. Present and future applications of contrast agents]. / Interacción entre microburbujas y ultrasonido. Aplicaciones presentes y futuras de los ecorrealzadores.

The way in which microbubbles (MB) increase the acoustic signal of blood was discovered incidentally during a hemodynamic study 30 years ago. Since then, new techniques and materials have been developed, looking for possible applications. Stability of MB has been increased, their size has been diminished, and interactions between MB and ultrasound have been understood. In this paper, we show the ways in which MB have been demonstrated or, at least, suggested to be useful in the fields of cardiological diagnosis and treatment.