Repaired tetralogy of Fallot: the roles of cardiovascular magnetic resonance in evaluating pathophysiology and for pulmonary valve replacement decision support

Surgical management of tetralogy of Fallot (TOF) results in anatomic and functional abnormalities in the majority of patients. Although right ventricular volume load due to severe pulmonary regurgitation can be tolerated for many years, there is now evidence that the compensatory mechanisms of the right ventricular myocardium ultimately fail and that if the volume load is not eliminated or reduced by pulmonary valve replacement the dysfunction might be irreversible. Cardiovascular magnetic resonance (CMR) has evolved during the last 2 decades as the reference standard imaging modality to assess the anatomic and functional sequelae in patients with repaired TOF. This article reviews the pathophysiology of chronic right ventricular volume load after TOF repair and the risks and benefits of pulmonary valve replacement. The CMR techniques used to comprehensively evaluate the patient with repaired TOF are reviewed and the role of CMR in supporting clinical decisions regarding pulmonary valve replacement is discussed

The Relationships between Frailty and Quality of Life in Elderly Women with Breast Cancer

Background: It is well known that oncologic management of elderly patients is complicated, and physicians should well define the ultimate goals when choosing treatment modalities. Cancer treatment should not necessarily focus on survival but aim for a good quality of life for the patient in light of their frailty.&#x0D; Patients and Methods: This is a retrospective cross-sectional survey study. One hundred fifty-eight women with breast cancer participated in this study. The PRISMA-7 Frailty Index and WHOQOL-OLD Module assessed participants’ frailty and quality of life. SPSS 26.0 and Medcalc 14 [Acacialaan 22, B-8400 Ostend, Belgium] programs were used for statistical analyses. Statistically significant associations between the PRISMA-7 scale and the WHOQOL-OLD Module were assessed.&#x0D; Results: Of the158 participants, the median age [min-max] was 71 [65-96] years, and 61.2% had stage I and II breast cancer. Lumpectomy was 61.1%, and 75% received chemotherapy-radiotherapy and hormone therapy. For the WHOQOL-OLD domains; financial status [p=0.001] with the sensory ability domain, work status [p&lt;0.001] and education status[p=0.004] with the autonomy domain, education status [p=0.002] with PPF activity domain, education status [p=0.001] and work status [p=0.007] with the social participation domain, treatment modality [p=0.003] with death &amp;dying domain, number of comorbidities [p=0.004] with intimacy domain statistically significant. The total score was associated with education status [p=0.005] and the number of comorbidities [p=0.010]. Frailty correlated positively with age [cut-off age 68 years; p&lt;0.001]. Education status was inversely associated with increased frailty [p=0.003]. The relationship between the PRISMA-7 scale and the WHOQOL-OLD Module correlated negatively in five out of six dimensions except for the Intimacy domain.&#x0D; Conclusions: It is necessary to design customized cancer management programs to improve specific components of elderly women with breast cancer with increased frailty by revealing the associations in domains of QoL.</jats:p

Myocardial metabolism during administration of a metabolic myocardial protection in coronary artery surgery [KORONER CERRAHI OLGULARINDA MIYOKARDIN METABOLIK KORUNMASI SIRASINDA METABOLIZMASI]

Preischemic glucose-insulin-potassium administration in open heart surgery has been implicated in better myocardial protection during cross clamping of the aorta. To assess the metabolic effects of myocardial substrate alteration in patients undergoing coronary artery bypass grafting (CABG), glucose (0.5 g/kg/h) - insulin (1 U/kg/h) - potassium (25 mmol/h) was administered intravenously for 30 minutes to 12 patients (Acute Parenteral Alimentation, APA) before cardiopulmonary bypass was commenced. Another 12 patients to whom 0.9 % NaCl and 25 mmol/h potassium was given with the same infusion rate served as control group. Simultaneous arterial (a) and coronary sinus (cs) samples were obtained before and after a 30 minute infusion period; samples were assayed for sodium, potassium, glucose, lactate and blood gas analysis. The cs potassium level in the APA group decreased from 4.377±0.196 to 3.787±0.146 mmol/L, whereas there was an increase from 4.033±0.062 to 4.650±0.070 mmol/L in the control group. The difference between two groups was significant, p<0.01. Upon infusion of glucose-insulin-potassium, myocardial glucose extraction (a-cs difference) increased from 54.42±6.28 mg/dl to 92.5±12 mg/dl; whereas it was reduced from 50.25±4.58 mg/dl to 37.67±4.43 mg/dl in the control group (p<0.01). While myocardial lactate extraction increased from 0.461±0.103 mmol/L to 0.987±0.114 mmol/L in APA group with the glucose-insulin administration (p<0.01), it remained unchanged in the control group. The enhancement of myocardial carbohydrate utilisation, evidenced with the increase in myocardial glucose and lactate uptake with the action of glucose-potassium-insulin before the initiation of cardiopulmonary bypass, would be particularly important for the patients undergoing myocardial revascularization that, this may further improve ischemic tolerance of the myocardium during cross clamping of the aorta

Myocardium utilizes more oxygen and glucose during tepid blood cardioplegic infusion in arrested heart

PubMed ID: 15876806The aims of this study were to evaluate myocardial metabolic activity during tepid blood cardioplegic infusion in the arrested heart in comparision with cold blood cardioplegia and to assess the early clinical outcomes of these patients. Thirty patients undergoing first elective coronary artery bypass grafting surgery were included and randomized to two groups (T for tepid and C for cold), 15 patients in each. Myocardial protection was similar in both groups except for the reinfusion of blood cardioplegia, which was 6°C in group C and 28°C in group T (same temperature as the body perfusion). The route of cardioplegic reinfusion was antegrade during the first reinfusion and retrograde during the second reinfusion. In order to assess myocardial metabolic activity, myocardial oxygen consumption (MVO2), myocardial glucose uptake, and myocardial lactate and acid production were all calculated. Arterial and coronary venous blood samples were obtained from the aortic root cannula and coronary sinus. During cardioplegic reinfusions in the ischemic period, the calculated values of myocardial oxygen extraction, oxygen consumption, and glucose uptake were higher in group T than in group C (P &lt; 0.05). This difference was observed during both antegrade and retrograde delivery of cardioplegic solution. Myocardial lactate production was greater in group C than in group T during cardioplegic reinfusion, both antegradely and retrogradely (P &lt; 0.05). In all patients, cardiopulmonary bypass was terminated in the first attempt. The clinical outcome was similar in both groups. The results of this study indicate that globally ischemic myocardium is able to utilize more oxygen and glucose during cardioplegic reinfusions at a tepid temperature in comparison to cold. In addition, the data showed evidence of less myocardial injury and better left ventricular function throughout the critical period of recovery from global ischemia for the heart protected by tepid cardioplegia. Copyright © 2005 by the International Heart Journal Association

Cardioplegia cristalóide, barotrauma e função endotelial: considerações experimentais

O presente ensaio experimental estudou o efeito da infusão de solução cardioplégica cristalóide a altas pressões sobre a função endotelial de artérias epicárdicas de cães. Não se encontraram alterações a nível de receptores (curvas dose-respostas à ACH e ADP; da transdução do sinal iniciado nos receptores/sitema de G-proteínas (fluoreto de sódio) e nos processos intracelulares da produção de EDRF/ NO (fosfolipase C e ionóforo do cálcio A23187). A função da musculatura lisa vascular não foi afetada quando se analisaram as respostas relaxantes (nitroprussiato de sódio e isoproterenol) e contrateis (KCI e prostaglandina 2alfa). Estes achados permitem as seguintes considerrações especulativas: a) O barotrauma produzido pela infusão da cardioplegia cristalóide a altas pressões ocorreria apenas em circulações coronarianas previamente doentes? b) Uma vez que as infusões duraram de 2 a 3 minutos, seria o barotrauma coronariano um fenômeno dependente do tempo de infusão? c) Para que ocorra o barotrauma seriam necessários níveis mais elevados de potássio? d) Questionar a existência do fenômeno do barotrauma coronariano produzido pela infusão de soluções cadioplégicas pelo menos nas condições experimentais utilizadas, e) A metodologia empregada estuda apenas as reatividades vasculares de artérias coronárias epicárdicas. Estas artérias seriam menos sensíveis aos efeitos da pressão de infusão da cardioplegia do que a microcirculação coronariana? f) Seria a circulação coronária do cão menos sensível a altas pressões do que do homem? Estas observações experimentais sugerem que a infusão de cardioplegia cristalóide, moderadamente hipocalêmica, a altas pressõe em um tempo de 2 a 3 minutos, não interfere com a produção de EDRF/NO pelo endotélio de coronárias epicárdicas do cão

Reatividade vascular da artéria mamária interna: estudos farmacológicos comparativos entre artérias caninas direita e esquerda

Para estudos comparativos da reatividade vascular entre artéria mamária interna (AMI) canina direita e esquerda, realizaram-se experimentos "in vitro" utilizando-se banhos orgânicos ("organ chambers") e ensaios biológicos: 1) os produtos plaquetários ADP e 5-HT induziram, respectivamente, vasodilatação dependente e independente do endotélio; 2) os autacóides, bradicinina e histamina, também induziram vasodilatação, respectivamente, dependente e independente do endotélio; 3) o A23187, vasodilatador independente de receptor, induziu relaxamentos dependentes do endotélio; 4) dopamina, dobutamina, papaverina e a poli-L-arginina induziram vasodilatações independentes do endotélio; 5) a NOR induziu intensa vasoconstrição comparável à causada pelo KCI e pela endotelina; 6) em 83% de 24 ensaios, a liberação basal de NO foi maior na AMI esquerda, em comparação com a AMI direita; 7) ensaios biológicos de AMIs demonstraram a importância da PGI2 nas condições de hipóxia, uma vez que a indometacina aboliu vasodilatação adicional em resposta à hipóxia em condições de vasodilatação induzida pela liberação basal de NO; 8) não ocorreram diferenças significantes de resposta, comparando-se estudos realizados em AMIs direita e esquerda

Efeito protetor da criocardioplegia cristalóide na isquemia global e reperfusão durante circulação extracorpórea: um mecanismo dependente do endotélio?

Estudos prévios demonstraram que o comprometimento da produção de EDRF/NO mediada por receptores, após isquemia global e reperfusão, possa ser devido a uma disfunção de G-proteínas que liga os receptores da célula endotelial à via da síntese de EDRF/NO. O presente trabalho experimental sugere que a criocardioplegia cristalóide, associada a hipotermia tópica, previne ou pode reverter, em parte, a disfunção endotelial nas mesmas condições. Mais estudos serão necessários para conclusões mais definitivas, pois as análises estatísticas mais acuradas sugeriram aumento da amostragem. Este detalhe talvez seja devido às grandes dificuldades de uniformização relacionada a este tipo de experimentos. Além disso, demonstrou-se pela primeira vez que a hipotermia, por si só, pode estimular a liberação de EDRF/NO pelo endotélio vascular. Isto sugere que o endotélio possa ser um importante sensor de mudanças da temperatura sangüínea e tem importantes implicações para o entendimento da fisiologia da CEC e dos mecanismos locais de auto-regulação.Previous experiments showed evidence of impaired receptor-mediated production of EDRF/NO following reperfusion injury could be due to G-protein dysfunction which links endothelial cell receptors to the pathway of EDRF/NO synthesis. This experimental research suggested that criocrystalloid cardioplegia, associated to topic hypotermia, could prevent or reverse the endothelium disfunction under same experimental conditions. More experiments will be necessary to get definitive conclusions, because fine statystical analysis suggested increasing the number of experiments. Otherwise, the present study proved for the first time that hypothermia alone can cause the release of PGI2 and EDRF/NO from the endothelium. This suggests that the endothelium could be an important temperature sensor and has important implications for the understanding of cardiopulmonary bypass physiology and local vascular autoregulation