After orthotopic heart transplantation (OHT), the allograft undergoes characteristic alterations in myocardial structure, including hypertrophy, increased ventricular stiffness, ischemia, and inflammation, all of which may decrease overall graft survival. Methods to quantify these phenotypes may clarify the pathophysiology of progressive graft dysfunction post-OHT. We performed cardiac magnetic resonance (CMR) with T1 mapping in 26 OHT recipients (mean age 47 ± 7 years, 30 % female, median follow-up post-OHT 6 months) and 30 age-matched healthy volunteers (mean age 50.5 ± 15 years; LVEF 63.5 ± 7 %). OHT recipients had a normal left ventricular ejection fraction (LVEF 65.3 ± 11 %) with higher LV mass relative to age-matched healthy volunteers (114 ± 27 vs. 85.8 ± 18 g; p < 0.001). There was no late gadolinium enhancement in either group. Both myocardial extracellular volume fraction (ECV) and intracellular lifetime of water (τ), a measure of cardiomyocyte hypertrophy, were higher in patients post-OHT (ECV: 0.39 ± 0.06 vs. 0.28 ± 0.03, p < 0.0001; τ: 0.12 ± 0.08 vs. 0.08 ± 0.03, p < 0.001). ECV was associated with LV mass (r = 0.74, p < 0.001). In follow-up, OHT recipients with normal biopsies by pathology (ISHLT grade 0R) in the first year post-OHT exhibited a lower ECV relative to patients with any rejection ≥2R (0.35 ± 0.02 for 0R vs. 0.45 ± 0, p < 0.001). Higher ECV but not LVEF was significantly associated with a reduced rejection-free survival. After OHT, markers of tissue remodeling by CMR (ECV and τ) are elevated and associated with myocardial hypertrophy. Interstitial myocardial remodeling (by ECV) is associated with cellular rejection. Further research on the impact of graft preservation and early immunosuppression on tissue-level remodeling of the allograft is necessary to delineate the clinical implications of these findings.

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The rotation of rollers in cardiopulmonary bypass pumps propels the blood through various devices to reach the patient. Very occlusive settings may squeeze red blood cells, whereas a nonocclusive setting may result in retrograde flow. Occlusion of roller pumps may be regulated either by measuring the drop rate or by dynamic calibration. This study evaluated the influence of silicone tubing residual stress found on pump regulation. Silicone tubes obtained from two different suppliers were used in 6-inch DeBakey roller pumps. The variations occurring over time in the measurements of drop rate, dynamic calibration, and tube residual stress were analyzed. Covariance analysis of the four linear regressions has shown a progressive and accentuated reduction in drop rate (p < 0.002). It is noticeable that the angular coefficients of the drop rate measurements of the four silicone tubes are the same (p > 0.56). This reduction in drop rate measurements may affect the regulation of the pumps before surgical procedures. One probable cause for this reduction is the residual stress found in the silicone tubes. Settings based on the dynamic calibration process tended to be repeated over time. Simple linear regression test (angular coefficient equals zero) has shown a p > 0.79 showing no interference of the silicone tubes residual stress on dynamic calibration, suggesting that one should use this method to calibrate roller pumps.

Teste de caminhada de seis minutos como ferramenta para avaliar a qualidade de vida em pacientes submetidos à cirurgia de revascularização miocárdicaSix-minute walk test as a tool for assessing the quality of life in patients undergoing coronary artery bypass grafting surgery Abstract Objective: Evaluate the quality of life in patients undergoing myocardial revascularization using the sixminute walk test.Methods: This is a prospective observational study with patients undergoing CABG. We recorded the following clinical variables: the six-minute walk test and the SF-36 test. The patients were evaluated at the preoperative time and at 2 months of the postoperative period. Patients were evaluated preoperatively and divided into two groups according to the 6-minute walking test: the group with a walking course of >350 meters and the group with a walking course of less than 350 meters at the preoperative time.Results: The study population included 87 patients. Mean age was similar in both groups (59 ± 9.5 years vs. 61 ± 9.3 years, respectively, P = 0.24). Distances walked were significantly longer in the group with a walking course of >350 meters compared to the group with a walking course of <350 meters after 2 months of operation (436 ± 78 meters vs. 348 ± 87 meters; P <0.01). The quality of life was lower in the group with a walking course of <350 meters compared to the group with a walking course of >350 meters in the preoperative period in the following domains: functional capabilities, limitations due to physical aspects, overall health feelings, vitality, and social aspects. Quality of life improved after two months in both groups.Conclusions: The six-minute walk test at the preoperative time is associated with the quality of life after two months of coronary artery bypass grafting. In overall, quality of life has improved in all patients. The improvement in the quality of life was greater in those patients with a walking course of >350 meters at the preoperative time. 232Baptista VC, et al. -Six-minute walk test as a tool for assessing the quality of life in patients undergoing coronary artery bypass grafting surgery Bras Cir Cardiovasc 2012;27(2):231-9 Rev

The PVAM shows promising properties for its potential use as a novel pericardial substitute.