Eduard Fernandez-Nofrerias

Early dysfunction and long-term improvement in endothelium-dependent vasodilation in the infarct-related artery after thrombolysis☆

OBJECTIVES This study assessed the degree of endothelial dysfunction in post-acute myocardial infarction (AMI) and its subsequent status in the infarct-related artery (IRA) in patients treated with thrombolysis. BACKGROUND Coronary flow reserve alterations in the IRA after thrombolysis have been described, but the endothelium-dependent vasomotion has not been investigated, to date. METHODS Endothelial function in patients after thrombolysis was assessed by infusion of acetylcholine (ACh) at increasing doses in the IRA. Diameter changes in the distal segments were evaluated using quantitative coronary angiography. Patients with coronary atherosclerosis constituted the control group. Clinical variables, electrocardiography and biochemical markers were used to determine the timing of reperfusion and the extent of the infarct. Patients in the AMI group were re-evaluated one year later. RESULTS In the initial assessment, 16 patients showed a vasoconstriction response to ACh in the IRA compared to the control group (-20 +/- 21% vs. 4 +/- 4%; p < 0.01). Significant correlations between the degree of vasoconstriction and maximum value of the creatine kinase-MB fraction and number of new Q waves were observed. Of the 12 patients re-evaluated, 4 had complete occlusion of the IRA. In the remaining eight patients with patent artery, an improvement in response to ACh was observed relative to the initial study (+3 +/- 11%, vs. -19 +/- 15%, p < 0.05). CONCLUSIONS In patients with AMI treated with thrombolysis, severe endothelial dysfunction in the IRA is observed early. In patients who retain patency of the IRA, the endothelial dysfunction improves during the follow-up and suggests a component of stunned endothelium in the first few days post-AMI.

Analisis de los tiempos de atencion en pacientes con infarto agudo de miocardio tratados con angioplastia primaria segun su procedencia y segun el horario de realizacion del procedimiento

INTRODUCTION AND OBJECTIVES In primary angioplasty, the interval between first medical contact (FMC) and reperfusion should be less than 120 minutes. The time to reperfusion varies depending on where FMC is established. Recent studies suggest longer times in patients presenting in off-hours. The objective is to evaluate the time intervals between the onset of symptoms and reperfusion according to where the FMC occurs and time of day of patient presentation. METHODS Prospective observational study of acute myocardial infarction patients treated with primary angioplasty (February 2007 to May 2009). Depending on the FMC, patients were classified as belonging to the hospital group (hospital with primary angioplasty), the transfer group (hospital without primary angioplasty), or the emergency medical system (EMS) group (out-of-hospital care). For each group, the prehospital delay, diagnostic delay, delay in activation and/or transfer, and procedure delay were recorded. RESULTS Primary angioplasty was performed in 457 patients: 155 in the hospital group, 228 in the transfer group and 72 in the EMS group. The median [interquartile range] door-to-reperfusion times were 80 [63-107], 148 [118-189] and 81 [66-98] minutes, respectively (P<.0001). The transfer group showed a greater delay in diagnosis (P<.0001) and delayed activation and/or transfer (P<.0001). The EMS group had the shortest total time due to a reduced prehospital delay (P=.001). No difference was found with regard to the time of presentation (P=.42). CONCLUSIONS Transfer group patients were treated later and EMS group patients much earlier. There were no differences in association with the time of presentation. The identification of inappropriate delays should enable the introduction of measures to improve the efficiency of treatment.

Transradial percutaneous coronary intervention in cardiogenic shock: a single-center experience.

BACKGROUND Use of the transradial approach (TRA) in percutaneous coronary intervention (PCI) has increased in recent years. TRA has a lower mortality rate than the transfemoral approach (TFA) in patients with acute coronary syndrome. Comparative studies have systematically excluded patients with cardiogenic shock (CS). METHODS We performed a prospective, observational registry study of consecutive patients undergoing emergent revascularization between February 2007 and January 2012. An analysis of the clinical evolution of patients with CS during hospitalization was performed. RESULTS Of 1,400 emergency procedures, 122 had CS, of which 80 underwent PCI by TRA (65.6%) and 42 underwent PCI by TFA (34.3%). The main reason for choosing TFA was the absence of radial pulse (54.9%). Mortality (64.3% vs 32.5%, P = .001), serious access site complications (11.9% vs 2.5%, P = .03), access site complications requiring blood transfusion (7.1% vs 0%, P = .04), and major adverse cardiac events (death, infarction, stroke, serious bleeding, and postanoxic encephalopathy) (73.8% vs 43.8%, P = .001) were greater in patients treated by TFA. In the multivariate analysis, TRA was a predictor of mortality (odds ratio [OR] 0.39 [0.15-0.97]); other predictive factors were age ≥75 years (3.47 [1.35-8.92]), previous treatment with diuretics (3.67 [1.21-11.12]), and success of the procedure (0.07 [0.02-0.24]). CONCLUSIONS Transradial approach for PCI is possible and safe in up to two-thirds of patients with CS. Absence of radial pulse was the main factor preventing use of TRA. In multivariate analysis, TRA was associated with a lower risk of mortality.

ECOC Random Fields for Lumen Segmentation in Radial Artery IVUS Sequences

The measure of lumen volume on radial arteries can be used to evaluate the vessel response to different vasodilators. In this paper, we present a framework for automatic lumen segmentation in longitudinal cut images of radial artery from Intravascular ultrasound sequences. The segmentation is tackled as a classification problem where the contextual information is exploited by means of Conditional Random Fields (CRFs). A multi-class classification framework is proposed, and inference is achieved by combining binary CRFs according to the Error-Correcting-Output-Code technique. The results are validated against manually segmented sequences. Finally, the method is compared with other state-of-the-art classifiers.

Results of Primary Percutaneous Coronary Intervention in Patients ≥75 Years Treated by the Transradial Approach

Previous trials in elderly patients with ST-elevation myocardial infarction (STEMI) have not shown a definitive benefit of primary percutaneous coronary intervention (PPCI) by transfemoral approach over thrombolysis. The transradial approach (TRA) is associated with a significant decrease in mortality, MACE (Major Adverse Cardiac Event), and serious access site complications compared with the transfemoral approach. We have evaluated clinical outcomes in a cohort of real-life unselected ≥75-year-old patients with STEMI treated by TRA-PPCI. This is a single-center prospective, observational registry of consecutive patients with STEMI who underwent PPCI between February 2007 and February 2013. MACE was defined as death, reinfarction, or stroke. A total of 307 patients were treated by PPCI, 293 (95.1%) with TRA-PPCI (mean age 80 ± 2 years, 42% women). Patients had high co-morbidity levels (cardiogenic shock on admission 8.5%, previous myocardial infarction 11.6%, diabetes 30.4%, previous renal failure 25.6%, previous PCI 9.6%, and peripheral arterial disease 14.3%); IIbIIIa inhibitors were used in 45.1% of patients. Severe bleeding and need for transfusion were recorded for 6.5% and 9.9% of patients, respectively. In-hospital mortality, 1-year mortality, and 1-year MACE were 11.9%, 17.4%, and 22.2%, respectively. Excluding 25 patients with cardiogenic shock on admission, the in-hospital mortality, 1-year mortality, and 1-year MACE were 7.8%, 13.1%, and 17.9%, respectively. In conclusion, TRA-PPCI was feasible in the vast majority of elderly patients with STEMI. In-hospital mortality, 1-year mortality, and 1-year MACE were lower than reported for transfemoral access, suggesting a benefit of the TRA in these patients.

Mejoría de la función endotelial al reducir las concentraciones lipídicas en pacientes con hipercolesterolemia y arterias coronarias normales

Introduccion y objetivos En pacientes con factores de riesgo coronario se ha documentado la presencia de disfuncion endotelial en las arterias epicardicas. El proposito del estudio fue determinar si la disfuncion endotelial en pacientes hipercolesterolemicos y coronarias angiograficamente normales mejoraba despues de reducir y mantener normalizadas las concentraciones lipidicas. Pacientes y metodo En 10 pacientes con hipercolesterolemia y coronarias sin lesiones angiograficas, la vasomotilidad dependiente del endotelio se estudio mediante la administracion intracoronaria de acetilcolina en la arteria descendente anterior. Los cambios vasomotores fueron analizados mediante angiografia cuantitativa. Cinco pacientes sin factores de riesgo y con coronarias normales formaron el grupo control. Los pacientes hipercolesterolemicos fueron tratados con lovastatina y dieta, reevaluandose la funcion endotelial 24 ± 4 meses despues. Resultados En el estudio inicial los pacientes hipercolesterolemicos presentaron una respuesta vasoconstrictora a dosis crecientes de acetilcolina (10–6 M, 10–5 M y 10–4 M) indicativa de disfuncion endotelial (grupo estudio: –0,3 ± 10%, –6 ± 4% y –18 ± 10%, frente al grupo control: –0,6 ± 6%, –2 ± 6% y 3 ± 6%; p Conclusion En pacientes con hipercolesterolemia y coronarias angiograficamente normales en quienes se documenta disfuncion endotelial, la reduccion y normalizacion de las concentraciones lipidicas condiciona una mejoria de dicha disfuncion endotelial.

Approaching Artery Rigid Dynamics in IVUS

Tissue biomechanical properties (like strain and stress) are playing an increasing role in diagnosis and long-term treatment of intravascular coronary diseases. Their assessment strongly relies on estimation of vessel wall deformation. Since intravascular ultrasound (IVUS) sequences allow visualizing vessel morphology and reflect its dynamics, this technique represents a useful tool for evaluation of tissue mechanical properties. Image misalignment introduced by vessel-catheter motion is a major artifact for a proper tracking of tissue deformation. In this work, we focus on compensating and assessing IVUS rigid in-plane motion due to heart beating. Motion parameters are computed by considering both the vessel geometry and its appearance in the image. Continuum mechanics laws serve to introduce a novel score measuring motion reduction in in vivo sequences. Synthetic experiments validate the proposed score as measure of motion parameters accuracy; whereas results in in vivo pullbacks show the reliability of the presented methodologies in clinical cases.

Coronary Artery Perforation by Intracoronary Guidewires: Risk Factors and Clinical Outcomes

The aims of this study were to determine the incidence of coronary artery perforation by intracoronary guide wires during angioplasty, to identify associated factors, and to assess outcomes. The retrospective analysis covered 4,353 consecutive procedures, corresponding to a total 6,994 lesions treated over a period of 8 years. Coronary artery perforation by guide wires occurred in 15 cases (0.35%). Perforation was associated with the number of hydrophilic wires used (odds ratio=2.33; 95% confidence interval, 1.34-4.05) and treatment of chronic occlusions (odds ratio=3.31; 95% confidence interval, 1.05-10.46). Cardiac tamponade occurred in seven cases (46.7%), six of which were subacute. Three cases were resolved by pericardiocentesis, while four required surgical drainage. Cardiac tamponade was associated with the number of guide wires used (P=.039) and the use of abciximab (P=.016). No death occurred.

Perforación coronaria causada por guías intracoronarias: factores de riesgo y evolución clínica

En el presente estudio se valora la incidencia, los parametros relacionados y la evolucion de la perforacion coronaria por guia intracoronaria durante la realizacion de angioplastia. Se analizaron retrospectivamente 4.353 procedimientos consecutivos, correspondientes a 6.994 lesiones tratadas en 8 anos. Se detecto perforacion coronaria por guia en 15 casos (0,35%). Esta se relaciono con el numero de guias hidrofilas usadas (odds ratio [OR] = 2,33; intervalo de confianza [IC] del 95%, 1,34-4,05) y el tratamiento de oclusiones cronicas (OR = 3,31; IC del 95%, 1,05-10,46). En 7 casos (46,7%) hubo taponamiento cardiaco, 6 de manera subaguda; 3 se solucionaron con pericardiocentesis y 4 requirieron drenaje quirurgico. El taponamiento se relaciono con el numero de guias utilizadas (p = 0,039) y el uso de abciximab (p = 0,016). No se produjeron muertes.

Internal and External Coronary Vessel Images Registration

The growing appreciation of the pathophysiological and prognostic importance of arterial morphology has led to the realization that angiograms are inherently limited in defining the distribution and extension of coronary wall disease. By Intravascular Ultrasound images physicians have a picture of the composition of vessel in detail. However, observing an intravascular ultrasound stack of images, it is difficult to figure out the image position and extension with regard to the vessel parts and ramifications, and misclassification or misdiagnosis of lesions is possible. The objective of this work is to develop a computer vision technique to fuse the information from angiograms and intravascular ultrasound images defining the correspondence of every ultrasound image with a corresponding point of the vessel in the angiograms.