Infarto do miocárdio experimental em ratos: Análise do modelo

One of the most often used strategies to study the physiopathological alterations caused by coronary occlusion is the use of the experimental infarction model in rats. Among other factors, this is due to the similarities in the physiopathological alterations that occur after the infarction in humans. One must consider, however, that this model has characteristics that can hinder the use as well as the interpretation of eventual outcomes. Thus, this review aims at analyzing the main characteristics of the experimental infarction model in rats, discussing the coronary occlusion technique, the consequences and the methods of morphological and functional assessment of the infarction and its clinical implications.

Evaluation of blood compatibility of plasma deposited heparin-like films and SF6 plasma treated surfaces

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Influência da nifedipina sobre a incidência de insuficiência renal aguda no pós-operatório de revascularização do miocárdio com circulação extracorpórea

Pós-graduação em Bases Gerais da Cirurgia - FMB

Variação intraoperatória do sódio sérico e complicações neurológicas pós-operatórias em cirurgia cardíaca pediátrica

Pós-graduação em Anestesiologia - FMB

Correlação de variáveis metabólicas do perioperatório com complicações pós-operatórias em cirugia cardíaca pediátrica

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Sintomas depressivos e experiência pessoal de pacientes submetidos à cirurgia eletiva de revascularização do miocárdio

Pós-graduação em Psicologia do Desenvolvimento e Aprendizagem - FC

Fatores de risco pré-operatórios para mediastinite após cirurgia cardíaca: análise de 2768 pacientes

INTRODUÇÃO: A esternotomia mediana longitudinal é a via de acesso mais utilizada no tratamento das doenças cardíacas. As infecções profundas da ferida operatória no pós-operatório das cirurgias cardiovasculares são uma complicação séria, com alto custo durante o tratamento. Diferentes estudos têm encontrado fatores de risco para o desenvolvimento de mediastinite e as variáveis pré-operatórias têm tido especial destaque. OBJETIVO: O objetivo deste estudo é identificar fatores de risco pré-operatórios para o desenvolvimento de mediastinite em pacientes submetidos a revascularização do miocárdio e a substituição valvar. MÉTODOS: Este estudo observacional representa uma coorte de 2768 pacientes operados consecutivamente. O período considerado para análise foi de maio de 2007 a maio de 2009 e não houve critérios de exclusão. Foi realizada análise univariada e multivariada pelo modelo de regressão logística das 38 variáveis pré-operatórias eleitas. RESULTADOS: Nesta série, 35 (1,3%) pacientes evoluíram com mediastinite e 19 (0,7%) com osteomielite associada. A idade média dos pacientes foi de 59,9 ± 13,5 anos e o EuroSCORE de 4,5 ± 3,6. A mortalidade hospitalar foi de 42,8%. Na análise multivariada, foram identificadas três variáveis como preditoras independentes de mediastinite: balão intra-aórtico (OR 5,41, 95% IC [1,83 -16,01], P=0,002), hemodiálise (OR 4,87, 95% IC [1,41 - 16,86], P=0,012) e intervenção vascular extracardíaca (OR 4,39, 95% IC [1,64 - 11,76], P=0,003). CONCLUSÃO: O presente estudo demonstrou que necessidade do suporte hemodinâmico pré-operatório com balão intra-aórtico, hemodiálise e intervenção vascular extracardíaca são fatores de risco para o desenvolvimento de mediastinite após cirurgia cardíaca.

Late remote ischemic preconditioning in children undergoing cardiopulmonary bypass: A randomized controlled trial

Objective: Cardiopulmonary bypass is associated with ischemia-reperfusion injury to multiple organs. We aimed to evaluate whether remote ischemic preconditioning performed the day before surgery for congenital heart disease with cardiopulmonary bypass attenuates the postoperative inflammatory response and myocardial dysfunction. Methods: This was a prospective, randomized, single-blind, controlled trial. Children allocated to remote ischemic preconditioning underwent 4 periods of 5 minutes of lower limb ischemia by a blood pressure cuff intercalated with 5 minutes of reperfusion. Blood samples were collected 4, 12, 24, and 48 hours after cardiopulmonary bypass to evaluate nuclear factor kappa B activation in leukocytes by quantification of mRNA of I kappa B alpha by real-time quantitative polymerase chain reaction and for interleukin-8 and 10 plasma concentration measurements by enzyme-linked immunosorbent assay. Myocardial dysfunction was assessed by N-terminal pro-B-type natriuretic peptide and cardiac troponin I plasma concentrations, measured by chemiluminescence, and clinical parameters of low cardiac output syndrome. Results: Twelve children were allocated to remote ischemic preconditioning, and 10 children were allocated to the control group. Demographic data and Risk Adjustment for Congenital Heart Surgery 1 classification were comparable in both groups. Remote ischemic preconditioning group had lower postoperative values of N-terminal pro-B-type natriuretic peptide, but cardiac troponin I levels were not significantly different between groups. Interleukin-8 and 10 concentrations and I kappa B alpha gene expression were similar in both groups. Postoperative morbidity was similar in both groups; there were no postoperative deaths in either group. Conclusions: Late remote ischemic preconditioning did not provide clinically relevant cardioprotection to children undergoing cardiopulmonary bypass. (J Thorac Cardiovasc Surg 2012;144:178-83)

Psychosoziale Belastung bei Herztransplantationskandidaten

Fragestellung: In der vorliegenden Untersuchung wurde geprüft, ob sich neu gelistete Herztransplantationskandidaten mit ischämischer Herzinsuffizienz (IKMP) und dilatativer Kardiomyopathie (DKMP) nach Kontrolle von Krankheitsschwere und Geschlecht in psychosozialen Variablen unterscheiden. Zudem wurde untersucht, ob psychosoziale Risikofaktoren für IKMP-Patienten stärker mit der 1-Jahres-Mortalität auf der Warteliste assoziiert sind als für DKMP-Patienten. Methode: Im Rahmen der multizentrischen, prospektiv angelegten Studie „Warten auf ein neues Herz“ bearbeiteten 160 DKMP- (16 % Frauen) und 122 IKMP-Patienten (13 % Frauen) kurz nach Aufnahme auf die Warteliste einen Fragebogen, der subjektiven Gesundheitszustand, Angst, Depressivität, soziale Unterstützung, Netzwerkgröße, Ärger, Ärgerausdruck und wartezeitspezifische Belastungen erfasste. Medizinische Daten zum Zeitpunkt der Listung und Veränderungen im Wartelistenstatus im 1-Jahres-Follow-Up wurden von Eurotransplant bereitgestellt. Ergebnisse: IKMP-Patienten waren im Vergleich mit DKMP-Patienten älter, häufiger ehemalige Raucher, hatten häufiger vorherige Herzoperationen erlebt, litten seltener unter einer Erregungsleitungsstörung, wurden seltener mit Aldosteronantagonisten sowie häufiger mit Katecholaminen behandelt. Nach Kontrolle dieser Variablen und unter Einbezug des Geschlechts berichteten nur Männer mit IKMP höhere Angstwerte und mehr Anger-In als Männer mit DKMP. Ein höheres Mortalitätsrisiko für IKMP-Patienten ein Jahr nach Aufnahme auf die Warteliste konnte nicht belegt werden. Auch zeigte sich keine Interaktion zwischen psychosozialer Belastung und Grunderkrankung hinsichtlich der Mortalität. Niedrige emotionale Unterstützung ging unabhängig von der Grunderkrankung mit einem dreifach erhöhten Mortalitätsrisiko einher. Fazit: Männer mit IKMP sind stärker durch negative Emotionen belastet als Männer mit DKMP. Eine weitere Risikogruppe stellen Personen mit niedriger emotionaler Unterstützung dar. Psychosoziale Risikofaktoren sollten daher bereits bei Aufnahme auf die Warteliste erfasst und Betreuungsangebote gezielt auf diese beiden Gruppen abgestimmt werden.

Recupero della funzione renale in pazienti con acute kidney injury (AKI) sottoposti a terapia sostitutiva renale

L’insufficienza renale acuta(AKI) grave che richiede terapia sostitutiva, è una complicanza frequente nelle unità di terapia intensiva(UTI) e rappresenta un fattore di rischio indipendente di mortalità. Scopo dello studio é stato valutare prospetticamente, in pazienti “critici” sottoposti a terapie sostitutive renali continue(CRRT) per IRA post cardiochirurgia, la prevalenza ed il significato prognostico del recupero della funzione renale(RFR). Pazienti e Metodi:Pazienti(pz) con AKI dopo intervento di cardiochirurgia elettivo o in emergenza con disfunzione di due o più organi trattati con CRRT. Risultati:Dal 1996 al 2011, 266 pz (M 195,F 71, età 65.5±11.3aa) sono stati trattati con CRRT. Tipo di intervento: CABG(27.6%), dissecazione aortica(33%), sostituzione valvolare(21.1%), CABG+sostituzione valvolare(12.6%), altro(5.7%). Parametri all’inizio del trattamento: BUN 86.1±39.4, creatininemia(Cr) 3.96±1.86mg/dL, PAM 72.4±13.6mmHg, APACHE II score 30.7±6.1, SOFAscore 13.7±3. RIFLE: Risk (11%), Injury (31.4%), Failure (57.6%). AKI oligurica (72.2%), ventilazione meccanica (93.2%), inotropi (84.5%). La sopravvivenza a 30 gg ed alla dimissione è stata del 54.2% e del 37.1%. La sopravvivenza per stratificazione APACHE II: <24=85.1 e 66%, 25-29=63.5 e 48.1%, 30-34=51.8 e 31.8%, >34=31.6 e 17.7%. RFR ha consentito l’interruzione della CRRT nel 87.8% (86/98) dei survivors (Cr 1.4±0.6mg/dL) e nel 14.5% (24/166) dei nonsurvivors (Cr 2.2±0.9mg/dL) con un recupero totale del 41.4%. RFR è stato osservato nel 59.5% (44/74) dei pz non oligurici e nel 34.4% dei pz oligurici (66/192). La distribuzione dei pz sulla base dei tempi di RFR è stata:<8=38.2%, 8-14=20.9%, 15-21=11.8%, 22-28=10.9%, >28=18.2%. All’analisi multivariata, l’oliguria, l’età e il CV-SOFA a 7gg dall’inizio della CRRT si sono dimostrati fattori prognostici sfavorevoli su RFR(>21gg). RFR si associa ad una sopravvivenza elevata(78.2%). Conclusioni:RFR significativamente piu frequente nei pz non oligurici si associa ad una sopravvivenza alla dimissione piu elevata. La distribuzione dei pz in rapporto ad APACHE II e SOFAscore dimostra che la sopravvivenza e RFR sono strettamente legati alla gravità della patologia.

Ottimizzazione di un protocollo di anticoagulazione regionale con citrato in CRRT

Ottimizzazione di un protocollo di anticoagulazione regionale con citrato in CRRT Introduzione: La necessità di un'anticoagulazione continua e l'ipofosforemia in corso di trattamento sono problemi costranti in corso di CRRT. Il nostro studio ha cercato di dimostrare l'efficacia e la sicurezza dell'anticoagulazione regionale con citrato in CVVH basato sull'utilizzo di una soluzione di citrato (18 mmol/L) associata ad una soluzione di reinfusione contenente fosfato, recentemente disponibile in commercio, al fine di ridurre l'ipofosfatemia in corso di CRRT. Metodi: Abbiamo utilizzato il nostro protocollo basato sull'utilizzo di una concentrazione di citrato contenente 18 mmol/l associata ad una soluzione di reinfusione contenente fosfato in un piccolo gruppo di pazienti ricoverati in terapia intensiva post-cardiochirurgica, sottoposti a CRRT per insufficienza renale acuta. Risultati: Il nostro protocollo ha garantito un'adeguata durata del circuito ed un ottimo controllo dell'equilibrio acido-base in ogni paziente. E' stata necessaria solo una minima supplementazione di fosforo in alcuni dei pazienti trattati. Conclusioni: Il nostro protocollo basato sull' utilizzo di una soluzione a concentrazione di citrato maggiore (18 mmol/l), permette un miglior controllo dell'equilibrio acido-base rispetto all'utilizzo della soluzione a più bassa concentrazione di citrato. L'uso di una minore dose di citrato ed il mantenimento di un target maggiore di calcio ionizzato all'interno del circuito sono comunque associati ad un'adeguata durata del circuito. I livelli di fosforemia sono rimasti sostanzialmente stabili nella maggior parte dei pazienti trattati, grazie alla presenza di fosfato nella soluzione utilizzata come reinfusione in post-diluizione.

Dual-loop circuits in postoperative atrial macro re-entrant tachycardias

Background Patients late after open-heart surgery may develop dual-loop reentrant atrial arrhythmias, and mapping and catheter ablation remain challenging despite computer-assisted mapping techniques. Objectives The purpose of the study was to demonstrate the prevalence and characteristics of dual-loop reentrant arrhythmias, and to define the optimal mapping and ablation strategy. Methods Fourty consecutive patients (mean age 52+/-12 years) with intra-atrial reentrant tachycardia (IART) after open-heart surgery (with an incision of the right atrial free wall) were studied. Dual-loop IART was defined as the presence of two simultaneous atrial circuits. Following an abrupt tachycardia change during radiofrequency (RF) ablation, electrical disconnection of the targeted reentry isthmus from the remaining circuit was demonstrated by entrainment mapping. Furthermore, the second circuit loop was localized using electroanatomic mapping and/or entrainment mapping. Results Dual-loop IART was demonstrated in 8 patients (20%, 5 patients with congenital heart disease, 3 with acquired heart disease). Dual-loop IART included an isthmus-dependant atrial flutter combined with a reentry related to the atriotomy scar. The diagnosis of dual-loop IART required the comparison of entrainment mapping before and after tachycardiamodification. Overall, 35 patients had successful RF ablation (88%). Success rates were lower in patients with dual-loop IART than in patient without dual-loop IART. Ablation failures in 3 patients with dual-loop IART were related to the inability to properly transect the second tachycardia isthmus in the right atrial free wall. Conclusions Dual-loop IART is relatively common after heart surgery involving a right atriotomy. Abrupt tachycardia change and specific entrainment mapping maneuvers demonstrate these circuits. Electroanatomic mapping appears to be important to assist catheter ablation of periatriotomy circuits.

Oxidative stress precedes peak systemic inflammatory response in pediatric patients undergoing cardiopulmonary bypass operation

Oxidative stress seems to contribute to cardiopulmonary bypass (CPB)-related postoperative complications. Pediatric patients are particularly prone to these complications. With this in mind, we measured oxidative stress markers in blood plasma of 20 children undergoing elective heart surgery before, during, and up to 48 h after cessation of CPB, along with inflammatory parameters and full analysis of iron status. Ascorbate levels were decreased by approximately 50% (P < 0.001) at the time of aorta cross-clamp removal (or pump switch-off in 4 patients with partial CPB), and associated with corresponding increases in dehydroascorbate (P < 0.001, r = -0.80) and malondialdehyde (P < 0.01, r = -0.59). In contrast to the immediate oxidative response, peak levels of IL-6 and IL-8 were not observed until 3-12 h after CPB cessation. The early loss of ascorbate correlated with duration of CPB (P < 0.002, r = 0.72), plasma hemoglobin after cross-clamp removal (P < 0.001, r = 0.70), and IL-6 and IL-8 levels at 24 and 48 h after CPB (P < 0.01), but not with postoperative lactate levels, strongly suggesting that hemolysis, and not inflammation or ischemia, was the main cause of early oxidative stress. The correlation of ventilation time with early changes in ascorbate (P < 0.02, r = 0.55), plasma hemoglobin (P < 0.01, r = 0.60), and malondialdehyde (P < 0.02, r = 0.54) suggests that hemolysis-induced oxidative stress may be an underlying cause of CPB-associated pulmonary dysfunction. Optimization of surgical procedures or therapeutic intervention that minimize hemolysis (e.g., off-pump surgery) or the resultant oxidative stress (e.g., antioxidant treatment) should be considered as possible strategies to lower the rate of postoperative complications in pediatric CPB.

Minimized cardiopulmonary bypass combined with a smart suction device: the future of cardiopulmonary bypass?

OBJECTIVE: The standard heart-lung machine is a major trigger of systemic inflammatory response and the morbidity attributed to conventional extracorporeal circulation (CECC) is still significant. Reduction of blood-artificial surface contact and reduction of priming volume are principal aims in minimized extracorporeal circulation (MECC) cardiopulmonary bypass systems. The aim of this paper is to give an overview of the literature and to present our experience with the MECC-smart suction system. METHODS AND RESULTS: At our institution, 1799 patients underwent isolated coronary artery bypass grafting (CABG) surgery, 1372 with a MECC-smart suction system and 427 with CECC. All in-hospital data were assessed and the results were compared between the 2 groups. Patient characteristics and the distribution of EuroSCORE risk profile in our collective were similar between both groups. Average age in the MECC collective was 67.5 +/- 11.4 years and average EuroSCORE was 5.0 +/- 1.5. Average number of distal anastomoses was similar to the average number encountered in patients undergoing CABG surgery with CECC (3.3 +/- 1.0 for MECC versus 3.2 +/- 1.1 for CECC; P = ns). Myocardial protection is superior in MECC patients with lower postoperative maximal cTnI values (11.0 +/- 10.8 micromol/L for MECC versus 24.7 +/- 25.3 micromol/L for CECC; P < .05). Postoperative recovery was faster in patients operated on with the MECC-smart suction system and discharge from the hospital was earlier than for CECC patients (7.4 +/- 1.9 days for MECC versus 8.8 +/- 3.8 days for CECC; P < .05). CONCLUSIONS: The MECC-smart suction system is a safe perfusion technique for CABG surgery. In patients operated on with this system, the clinical outcome seems to be better than in patients operated on with CECC. This promising and less damaging perfusion technology has the potential to replace CECC systems in CABG surgery.

Multimodality Preoperative Planning and Postoperative Follow-up of a Hybrid Cardiac Intervention

We describe the case of a 59-year-old man who had aortic regurgitation and a hypoplastic aortic valve and for whom an echocardiography evaluation revealed a vascular tumor in the roof of the left atrium, which was suspected to be a hemangioma. After undergoing preoperative invasive catheter coronary angiography, echocardiography, and multislice computed tomography examinations, the patient underwent an aortic miniroot replacement. Intraoperative findings confirmed the findings of the preoperative evaluations. The tumor, although macroscopically verified as a hemangioma, was not resected because of the tumor's position and size, and the threat of uncontrollable bleeding. After an uneventful postoperative clinical course, a subsequent successful transcatheter coil occlusion of the coronary fistula from the left circumflex coronary artery was performed as an alternative to surgical resection of the tumor. This case emphasizes the future role of a multimodality hybrid approach for diagnosis, planning (different 2- and 3-dimensional imaging modalities), and treatment in the form of combining interventional (transcatheter) and surgical (open heart) techniques, which could optimize different treatment strategies. This approach could be further improved by increasing the installations of hybrid operating rooms.