Cristiano Freitas de Souza

Percutaneous Mechanical Assistance for the Failing Heart

One of the most challenging situations in contemporary medicine is, doubtlessly, the approach and treatment of patients presenting with severe left ventricle failure. Since its first clinical application in patients with cardiogenic shock in 1968, the intraaortic balloon pump (IABP) has been widely accepted by heart failure physicians. Although IABP therapy has been shown to be effective for the support and stabilization of hemodynamically compromised patients, it has failed to promote any improvements in patient outcomes. For this reason, much attention has been invested in the development of external devices that can collaborate with the treatment of this condition. In this context, the percutaneous left ventricle assist device (pLVAD), like TandemHeart (Cardiac Assist, Inc.; Pittsburgh, PA, USA), and, more recently, the Impella 2.5 (Abiomed Europe, Aachen, Germany) has emerged. The purpose of this review is to describe the history of pLVAD, from its beginning, to the other devices currently available, including those created for right ventricle and biventricular support.

Predictors and Long‐Term Clinical Impact of Acute Stent Malapposition: An Assessment of Dual Antiplatelet Therapy With Drug‐Eluting Stents (ADAPT‐DES) Intravascular Ultrasound Substudy

Background The impact of acute stent malapposition (ASM) on long‐term clinical outcomes in patients undergoing percutaneous coronary intervention is still controversial. We sought to evaluate predictors and long‐term clinical outcomes of ASM. Methods and Results ADAPT‐DES (Assessment of Dual Antiplatelet Therapy With Drug‐Eluting Stents) was a prospective multicenter study of 8663 patients undergoing percutaneous coronary intervention using drug‐eluting stents. In a prespecified intravascular ultrasound–guided substudy, 2072 patients with 2446 culprit lesions had post–percutaneous coronary intervention intravascular ultrasound and were classified according to the presence or absence of ASM. After intravascular ultrasound–guided percutaneous coronary intervention, the overall prevalence of ASM after successful drug‐eluting stents implantation was 14.4% per patient and 12.6% per lesion. Compared to lesions without ASM, lesions with ASM had larger in‐stent lumen areas, larger stent areas, and larger in‐stent vessel areas. A larger mean plaque area along with more attenuated plaque was observed in lesions with ASM versus lesions without ASM. Lesions with ASM had greater proximal and distal reference lumen areas and more distal, but not proximal, reference calcium compared to lesions without ASM. At 2‐year follow‐up, there was no significant difference in the incidence of cardiac death; myocardial infarction; early, late, or very late stent thrombosis; or clinically driven target lesion revascularization in patients with ASM versus those without ASM. Furthermore, ASM was not an independent predictor of 2‐year major adverse cardiac events or target lesion revascularization even when forced into the multivariate model. Conclusions In patients treated with intravascular ultrasound–guided drug‐eluting stents implantation, ASM was not associated with adverse clinical events during long‐term follow‐up including, but not limited to, stent thrombosis. Clinical Trial Registration URL: https://www.clinicaltrials.gov. Unique identifier: NCT00638794.

P2Y12 receptor inhibition with prasugrel and ticagrelor in STEMI patients after fibrinolytic therapy: Analysis from the SAMPA randomized trial☆

BACKGROUND A pharmacodynamic comparison between ticagrelor and prasugrel after fibrinolytic therapy has not yet been performed. METHODS In the single-center SAMPA trial, 50 consecutive STEMI patients previously treated with clopidogrel and undergoing a pharmacoinvasive strategy were randomized to either a ticagrelor (n=25) 180mg loading dose followed by 90mg bid, or a prasugrel (n=25) 60mg loading dose followed by 10mg/day, initiated after fibrinolytic therapy but before angiography. Platelet reactivity was assessed with the VerifyNow P2Y12 assay at 0, 2, 6, and 24h after randomization. RESULTS Mean times from fibrinolysis to prasugrel or ticagrelor administration were 11.1±6.9 and 13.3±6.3h, respectively (p=0.24). The values of PRU decreased significantly from baseline to 2h (all p<0.001) and from 2h to 6h (all p<0.001) in both groups. There was no difference in PRU values between 6h and 24h. The mean PRU values at 0, 2, 6, and 24h were 234.9, 127.8, 45.4, and 48.0 in the prasugrel group and 233.1, 135.1, 67.7, and 56.9 in the ticagrelor group, respectively. PRU values did not significantly differ between groups at any time period of the study. CONCLUSIONS In patients with STEMI treated with fibrinolytic therapy, platelet inhibition after clopidogrel is suboptimal and can be further increased with more potent agents. Ticagrelor and prasugrel demonstrated a similar extent of P2Y12 receptor inhibition within 24h, although maximal platelet inhibition after these potent agents was not achieved for 6h.

Células-Tronco Mesenquimais: Células Ideais para a Regeneração Cardíaca?

As celulas-tronco mesenquimais representam uma rara subpopulacao das celulas-tronco da medula ossea (< 0,01% das celulas mononucleares da medula ossea) com capacidade de expansao mitotica in vitro. Em decorrencia da facilidade em se dividir e proliferar, concluiu-se que as celulas-tronco mesenquimais seriam as celulas responsaveis pela manutencao e renovacao dos tecidos mesenquimais adultos, incluindo o musculo cardiaco. Esse tipo celular apresenta como uma de suas virtudes consideravel atividade imunossupressora, evitando assim efeitos adversos relacionados a rejeicao entre o material infundido e o hospedeiro. As celulastronco mesenquimais vem sendo cada vez mais estudadas, tanto em ensaios pre-clinicos como clinicos. Acreditamos que, superados alguns desafios em seu isolamento, preparo e modo de infusao, essas celulas poderao, em futuro proximo, representar o tipo celular ideal para a regeneracao cardiaca.

Segurança e eficácia dos stents farmacológicos eluidores de biolimus com polímero biodegradável: análise do registro EINSTEIN (Evaluation of Next-generation drug-eluting STEnt IN patients with coronary artery disease)

ABSTRACT Objective: To evaluate the incidence of major adverse cardiac events (cardiac death, or acute myocardial infarct, or target vessel revascularization) at one year in “real world” patients. Methods: The EINSTEIN registry is an observational, prospective, single center study that consecutively included 103 patients (152 lesions) treated with the Biomatrix™ stent, a biolimus A9-eluting stent with biodegradable polymer. Results: The mean age was 65.0±12.4 years; male gender represented 83.5% of the patients; and 37.9% of them were diabetic. At one-year, major adverse cardiac events occurred in 11.7% of the patients, including 2.9% of cardiac death, 4.9% of with non ST- segment elevation acute myocardial infarction, and 3.9% of target vessel revascularization. Stent thrombosis occurred in only 1% (1 patient) at one-yearfollow-up. Conclusion: The present Registry suggests that new generation biolimus A9 drug-eluting stents are safe and effective in a “real world”, all-comers patients, showing low rates of major cardiac adverse events on long-term follow-up.

Morphological changes and clinical impact of unstable plaques within untreated segments of acute myocardial infarction patients during a 3-year follow-up: an analysis from the HORIZONS-AMI trial.

ObjectivesPlaque ruptures and attenuated plaques are considered to be unstable and have been identified in both culprit and nonculprit lesions of patients with ST-segment elevation myocardial infarction (STEMI). However, there are limited data available on the natural evolution of these plaques and their long-term clinical outcome. We investigated the natural evolution and long-term impact of plaque ruptures and attenuated plaques in untreated segments of infarct-related arteries in patients with STEMI. MethodsIn the Harmonizing Outcomes with Revascularization and Stents in Acute Myocardial Infarction trial, 389 patients with 429 lesions underwent intravascular ultrasound (IVUS) at baseline. Follow-up IVUS at 13 months was conducted in 245 patients. Three-year follow-up data were available for all patients. ResultsSegments not treated between baseline and follow-up were compared. Baseline IVUS identified 29 plaque ruptures in 27 patients (7%). Of 11 plaque ruptures with follow-up IVUS, four healed and seven persisted. Conversely, through follow-up IVUS, nine new plaque ruptures in nine patients (4%) were identified. Attenuated plaques were identified in 31 of 38 plaque ruptures (81.5%), of which 24 were in the same circumferential segment as the ruptured cavity and seven were within 5 mm proximal or distal to the plaque rupture. Morphologic changes during follow-up, including new plaque ruptures and changes in the attenuated plaque frequency and distribution, were not accompanied by either serious lumen compromise or clinical events. ConclusionSerial IVUS analysis demonstrated that the morphology of unstable plaques within untreated segments in STEMI patients treated with optimal systemic therapies markedly changed during the 13-month follow-up period, without lumen compromise or clinical events at the 3-year follow-up.

Impact of chronic statin therapy on clinical presentation and underlying lesion morphology in patients undergoing percutaneous intervention: an Adapt-des Ivus substudy.

Objective Previous intravascular ultrasound (IVUS) studies have not established a relationship between chronic statin use and plaque morphology and composition in patients undergoing percutaneous coronary intervention (PCI). We sought to use pre-PCI grayscale and virtual histology (VH)-IVUS to assess plaque morphology and composition in patients treated with chronic statin therapy compared with patients who were not taking statins before admission and PCI. Methods In a prespecified substudy of the Assessment of Dual AntiPlatelet Therapy with Drug-Eluting Stents study, pre-PCI grayscale and VH-IVUS were performed in 780 patients with 916 culprit and 765 nonculprit lesions. Results Overall, 338 patients were treated with chronic statin therapy before admission. Statin-treated patients were older and had a higher prevalence of coronary risk factors. Statin-treated patients were more likely to present with stable angina, whereas non-statin-treated patients more frequently presented with acute myocardial infarction. Grayscale and VH-IVUS findings showed that lesions in statin-treated patients had a smaller plaque burden, but more dense calcium. Statin-treated patients had more calcified thick-cap fibroatheromas (9.2 vs. 3.7%, P=0.0007), but fewer VH-defined thin-cap fibroatheromas (45.2 vs. 56.1%, P=0.001) or plaque ruptures (26.6 vs. 38.4%, P=0.0001). In a propensity-matched population (n=249 in each group), similar results were obtained as regards clinical presentation and grayscale and VH-IVUS findings. Conclusion Chronic statin use in patients with coronary artery disease was associated with more stable clinical presentation and IVUS findings consistent with greater lesion stability (fewer VH-thin-cap fibroatheromas and plaque ruptures and more calcified thick-cap fibroatheromas).

Tissue characterization and phenotype classification in patients presenting with acute myocardial infarction: Insights from the iWonder study

We sought to assess a new modality of radiofrequency intravascular ultrasound (IVUS) called iMAP‐IVUS (Boston Scientific, Santa Clara, California) during the evaluation of patients presenting with high‐risk acute coronary syndromes.

Catheter-induced in-stented segment coronary dissection

Coronary angiography can lead to different kinds of complications. Catheter-induced coronary dissection is one of the most feared of them. It is uncommonly reported and may result in ischemic events ranging from angina to death. We report a case of a woman admitted to the hospital due to progressive effort angina who had a complication during percutaneous coronary intervention not previously reported. It is a usual thinking that a coronary artery stented segment would not be prone to dissect either spontaneously or catheter-induced. This report describes a catheter-induced in-stented segment coronary dissection and a discussion if the dissection line involving the left anterior descending coronary artery stented segment occurred between the stent and the intimal hyperplasia or between the stent and the adventitia.

TCT-525 Initial experience with the use of fractional flow reserve in percutaneous intervention of transplant renal artery stenosis

RESULTS In Cohort 1, CFR was significantly lower (2.12 0.79 vs. 2.56 0.63; p<0.001) and HMR was significantly higher (2.61 1.22 vs. 2.31 0.89; p1⁄40.04) in vessels with CAD than the vessels without CAD, within the same patient. mMR was equivalent in obstructed and nonobstructed vessels: 1.54 0.77 vs. 1.53 0.57; p1⁄40.90. Cohort 2 confirmed these findings, showing a significant relationship for CFR and HMR with diameter stenosis % (b1⁄4-0.013, 95%CI [-0.016 to -0.010]; p<0.001 for CFR and b1⁄40.008, 95%CI [0.004 to 0.011]; p<0.001 for HMR per 1%), while mMR was independent of diameter stenosis % (b1⁄40.002, 95%CI [-0.001 to 0.004] per 1%; p1⁄40.15). No association was found between mMR and any of the risk factors for cardiovascular disease.