Factores que determinan el tamaño del infarto de miocardio en el modelo experimental de oclusión coronaria transitoria en el cerdo: influencia de la hipertensión arterial y la taquicardia

Tesis doctoral inédita leída el 25-1-88 en la Universidad Autónoma de Madrid, Facultad de Medicina, Departamento de Farmacologí

Prevalence of Microvascular and Endothelial Dysfunction in the Nonculprit Territory in Patients With Acute Myocardial Infarction

BACKGROUND: Approximately half of the patients presenting with ST-segment-elevation myocardial infarction (STEMI) have multivessel disease. The physiology of the nonculprit artery has not been thoroughly studied to date. We sought to characterize the coronary physiology of the nonculprit artery in the early phase after STEMI and determine the real prevalence of microvascular and endothelial dysfunction. METHODS AND RESULTS: Patients with STEMI and another coronary artery lesion in a different territory were prospectively included in an observational single-center study. The protocol took place after revascularization of the culprit artery and comprised 3 phases: first, epicardial endothelial functional assessment using intracoronary acetylcholine; second, epicardial severity quantification based on fractional flow reserve, and nonendothelial microvascular function with coronary flow reserve and the index of microvascular resistance; third, endothelium-dependent microvascular function assessment based on the endothelial coronary flow reserve. Eighty-four patients were included. Mean age was 62 +/- 10 years, and 86.9% were men. Only 6 subjects had a nonpathological study: macrovascular endothelial dysfunction was present in 60% of the patients; fractional flow reserve 25 were evident in 34%, 37%, and 28% of the subjects respectively; and microvascular endothelial dysfunction (endothelial coronary flow reserve <1.5) was observed in 44%. In hospital-mortality was 0%, and no major complications occurred. At 6-month follow-up, there were no events related to the nonculprit artery. CONCLUSIONS: Microvascular and endothelial dysfunction in the nonculprit artery territory in patients with STEMI are very common. In 93% of the patients, we found functional abnormalities. Acetylcholine administration in the early phase post-STEMI in patients with multivessel disease is safe.Dr Díez del Hoyo has been funded by grants Programa Intramural de impulso a la investigación during 2016 (Instituto Investigación Sanitaria Gregorio Marañon, Spain) and since 2016 Contrato i-PFIS (Doctorados IIS-empresa en ciencias y tecnologías de la salud, Instituto de Salud Carlos III, Ministry of Economy, Industry and Competitivity, Spain)

Data from acellular human heart matrix

Perfusion decellularization of cadaveric hearts removes cells and generates a cell-free extracellular matrix scaffold containing acellular vascular conduits, which are theoretically sufficient to perfuse and support tissue-engineered heart constructs. This article contains additional data of our experience decellularizing and testing structural integrity and composition of a large series of human hearts, “Acellular human heart matrix: a critical step toward whole heat grafts” (Sanchez et al., 2015) [1]. Here we provide the information about the heart decellularization technique, the valve competence evaluation of the decellularized scaffolds, the integrity evaluation of epicardial and myocardial coronary circulation, the pressure volume measurements, the primers used to assess cardiac muscle gene expression and, the characteristics of donors, donor hearts, scaffolds and perfusion decellularization process

Long-Term Outcomes in Patients With New-Onset Persistent Left Bundle Branch Block Following TAVR.

The aim of this study was to determine the impact of new-onset persistent (NOP) left bundle branch block (LBBB) on long-term (>2 year) outcomes after transcatheter aortic valve replacement (TAVR). The impact of NOP-LBBB after TAVR remains controversial and no data exist regarding long-term outcomes. A total of 1,020 consecutive patients without pre-existing LBBB or permanent pacemaker implantation (PPI) undergoing TAVR were included. NOP-LBBB was defined as any new LBBB post-TAVR that persisted at hospital discharge. Follow-up clinical and echocardiographic data were obtained at a median of 3 years (interquartile range: 2 to 5 years) post-TAVR. NOP-LBBB occurred in 212 patients (20.1%) following TAVR. There were no differences between NOP-LBBB and no NOP-LBBB groups, except for a higher use of the self-expandable CoreValve system in the NOP-LBBB group (p  After a median follow-up of 3 years post-TAVR, NOP-LBBB was not associated with a higher mortality or heart failure rehospitalization. However, NOP-LBBB increased the risk of permanent pacemaker implantation and negatively impacted left ventricular function over time. These results should inform future efforts for improving the management of patients with NOP-LBBB post-TAVR

Long-Term Outcomes in Patients With New Permanent Pacemaker Implantation Following Transcatheter Aortic Valve Replacement.

This study sought to evaluate the long-term clinical impact of permanent pacemaker implantation (PPI) after transcatheter aortic valve replacement (TAVR). Conduction disturbances leading to PPI are common following TAVR. However, no data exist regarding the impact of PPI on long-term outcomes post-TAVR. This was a multicenter study including a total of 1,629 patients without prior PPI undergoing TAVR (balloon- and self-expandable valves in 45% and 55% of patients, respectively). Follow-up clinical, echocardiographic, and pacing data were obtained at a median of 4 years (interquartile range: 3 to 5 years) post-TAVR. PPI was required in 322 (19.8%) patients within 30 days post-TAVR (26.9% and 10.9% in patients receiving self- and balloon-expandable CoreValve and Edwards systems, respectively). Up to 86% of patients with PPI exhibited pacing >1% of the time during follow-up (>40% pacing in 51% of patients). There were no differences between patients with and without PPI in total mortality (48.5% vs. 42.9%; adjusted hazard ratio [HR]: 1.15; 95% confidence interval [CI]: 0.95 to 1.39; p = 0.15) and cardiovascular mortality (14.9% vs. 15.5%, adjusted HR: 0.93; 95% CI: 0.66 to 1.30; p = 0.66) at follow-up. However, patients with PPI had higher rates of rehospitalization due to heart failure (22.4% vs. 16.1%; adjusted HR: 1.42; 95% CI: 1.06 to 1.89; p = 0.019), and the combined endpoint of mortality or heart failure rehospitalization (59.6% vs. 51.9%; adjusted HR: 1.25; 95% CI: 1.05 to 1.48; p = 0.011). PPI was associated with lesser improvement in LVEF over time (p = 0.051 for changes in LVEF between groups), particularly in patients with reduced LVEF before TAVR (p = 0.005 for changes in LVEF between groups). The need for PPI post-TAVR was frequent and associated with an increased risk of heart failure rehospitalization and lack of LVEF improvement, but not mortality, after a median follow-up of 4 years. Most patients with new PPI post-TAVR exhibited some degree of pacing activity at follow-up

Arrhythmic Burden as Determined by Ambulatory Continuous Cardiac Monitoring in Patients With New-Onset Persistent Left Bundle Branch Block Following Transcatheter Aortic Valve Replacement: The MARE Study.

The authors sought to determine: 1) the global arrhythmic burden; 2) the rate of arrhythmias leading to a treatment change; and 3) the incidence of high-degree atrioventricular block (HAVB) at 12-month follow-up in patients with new-onset persistent left bundle branch block (LBBB) following transcatheter aortic valve replacement (TAVR). Controversial data exist on the occurrence of significant arrhythmias in patients with LBBB post-TAVR. This was a multicenter prospective study including 103 consecutive patients with new-onset persistent LBBB post-TAVR with the balloon-expandable SAPIEN XT/3 valve (n = 53), or the self-expanding CoreValve/Evolut R system (n = 50). An implantable cardiac monitor (Reveal XT, Reveal Linq) was implanted at 4 (3 to 6) days post-TAVR, and patients had continuous electrocardiogram monitoring for 12 months. All arrhythmic events were adjudicated in a central electrocardiography core lab. Primary endpoints were the incidence of arrhythmias leading to a treatment change, and the incidence of HAVB at 12-month follow-up. A total of 1,553 new arrhythmic events were detected in 44 patients (1,443 episodes of tachyarrhythmia in 26 patients [atrial fibrillation/flutter/atrial tachycardia: 1,427, ventricular tachycardia 16]; 110 episodes of bradyarrhythmia in 21 patients [HAVB 54, severe bradycardia 56]). All arrhythmic events were silent in 34 patients (77%), the arrhythmic event led to a treatment change in 19 patients (18%), and 11 patients (11%) required pacemaker or implantable cardioverter-defibrillator implantation (due to HAVB, severe bradycardia, or ventricular tachycardia episodes in 9, 1, and 1 patient, respectively). A total of 12 patients died at 1-year follow-up, 1 from sudden death. A high incidence of arrhythmic events was observed at 1-year follow-up in close to one-half of the patients with LBBB post-TAVR. Significant bradyarrhythmias occurred in one-fifth of the patients, and PPM was required in nearly one-half of them. These data support the use of a cardiac monitoring device for close follow-up and expediting the initiation of treatment in this challenging group of patients. (Ambulatory Electrocardiographic Monitoring for the Detection of High-Degree Atrio-Ventricular Block in Patients With New-onset PeRsistent LEft Bundle Branch Block After Transcatheter Aortic Valve Implantation [MARE study]: NCT02153307)