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Resumo:
The aim of this analysis was to compare vasoreactive properties of internal thoracic arteries (ITA) grafts from diabetic (DM) to those of non-diabetic (ND) patients. Ring segments of ITA, taken from patients undergoing coronary artery bypass grafting, were suspended in organ bath chambers filled with modified Krebs-Henseleit solution and contractile responses to potassium chloride (KCl), noradrenaline (NA), endothelin-1 (ET-l), and endothelium-dependent relaxant responses to acetylcholine (ACH) were recorded isometrically. The receptor-mediated agonists NA and ET-1 stimulated ITA from both groups within similar concentration ranges while ITA from DM patients proved to be significantly more sensitive to KCl than ITA from ND. Furthermore, maximal contractile responses indicated that KCl (3.79 +/- 0.30 g, n = 7 in DM and 2.50 +/- 0.23 g, n = 29 in ND, P < 0.05) evoked significantly higher responses in ITA from DM as compared to the ND control group while both NA and ET-l stimulated ITA from both groups with similar efficacies. Endothelium-dependent relaxant responses to ACH proved to be similar in both groups when expressed as percentages of the pre-existing tone. The present data support the contention that in comparison to ND controls arteries from DM patients are more sensitive to depolarization but endothelial dysfunction is less frequent in human ITA than expected from observations in systemic vascular beds.
Resumo:
Although U-clip anastomoses were studied for hemodynamics and patency, their potential for unimpeded growth after congenital cardiovascular surgery has not been investigated yet. In 53 children aged 2.1+/-3.3 years operated on between March 1998 and August 2005 growth of U-clip (U) vs. polypropylene running sutured (P) anastomoses in coarctation repair (Coarc; n=26), bi-directional Glenn (BDG; n=13) and arterial switch operation (ASO; n=14) was retrospectively analysed. Coarc showed 2.39+/-4.33 vs. 3.09+/-2.24 mm of growth during the observation period (21+/-16 vs. 30+/-27 months); no growth (0 vs.16%), restenosis (14 vs. 37%) and reinterventions (14 vs. 11%) were similar (all in U vs. P, P=ns). BDG showed 3.68+/-3.43 vs. 2.50+/-2.55 mm (P=ns) of growth during 15+/-5 vs. 29+/-18 months (P=0.046); no growth (17 vs. 0%), stenosis (0 vs. 14%) and reinterventions (0%) were similar in U vs. P, respectively (P=ns). Main pulmonary artery (MPA) anastomosis in ASO showed 0.28+/-1.73 vs. 1.30+/-3.16 mm of growth during 8+/-14 vs. 28+/-28 months; no growth (60 vs. 14%), stenosis (50 vs. 63%) and reinterventions (0%) were similar (all in U vs. P, P=ns). Anastomotic growth, stenosis and reintervention rates show no difference between interrupted U-clip and polypropylene running sutured technique in Coarc repair, BDG and MPA anastomosis in ASO.
Resumo:
We improved, evaluated, and used Sanger sequencing for quantification of single nucleotide polymorphism (SNP) variants in transcripts and gDNA samples. This improved assay resulted in highly reproducible relative allele frequencies (e.g., for a heterozygous gDNA 50.0+/-1.4%, and for a missense mutation-bearing transcript 46.9+/-3.7%) with a lower detection limit of 3-9%. It provided excellent accuracy and linear correlation between expected and observed relative allele frequencies. This sequencing assay, which can also be used for the quantification of copy number variations (CNVs), methylations, mosaicisms, and DNA pools, enabled us to analyze transcripts of the FBN1 gene in fibroblasts and blood samples of patients with suspected Marfan syndrome not only qualitatively but also quantitatively. We report a total of 18 novel and 19 known FBN1 sequence variants leading to a premature termination codon (PTC), 26 of which we analyzed by quantitative sequencing both at gDNA and cDNA levels. The relative amounts of PTC-containing FBN1 transcripts in fresh and PAXgene-stabilized blood samples were significantly higher (33.0+/-3.9% to 80.0+/-7.2%) than those detected in affected fibroblasts with inhibition of nonsense-mediated mRNA decay (NMD) (11.0+/-2.1% to 25.0+/-1.8%), whereas in fibroblasts without NMD inhibition no mutant alleles could be detected. These results provide evidence for incomplete NMD in leukocytes and have particular importance for RNA-based analyses not only in FBN1 but also in other genes.
Resumo:
Interventional treatment of hypertrophic obstructive cardiomyopathy has considerably developed and primary surgical approach is nowadays considered for a minority of patients with insufficient relief of obstruction following catheter intervention. We present the history of a patient who underwent alcohol ablation and developed a life-threatening ventricular septal defect consecutively to a large myocardial infarction because of alcohol injection into the LAD.
Resumo:
Most recently discussion about the optimal treatment for different subsets of patients suffering from coronary artery disease has re-emerged, mainly because of the uncertainty caused by doctors and patients regarding the phenomenon of unpredictable early and late stent thrombosis. Surgical revascularization using multiple arterial bypass grafts has repeatedly proven its superiority compared to percutaneous intervention techniques, especially in patients suffering from left main stem disease and coronary 3-vessels disease. Several prospective randomized multicenter studies comparing early and mid-term results following PCI and CABG have been really restrictive, with respect to patient enrollment, with less than 5% of all patients treated during the same time period been enrolled. Coronary artery bypass grafting allows the most complete revascularization in one session, because all target coronary vessels larger than 1 mm can be bypassed in their distal segments. Once the patient has been turn-off for surgery, surgeons have to consider the most complete arterial revascularization in order to decrease the long-term necessity for re-revascularization; for instance patency rate of the left internal thoracic artery grafted to the distal part left anterior descending artery may be as high as 90-95% after 10 to 15 years. Early mortality following isolated CABG operation has been as low as 0.6 to 1% in the most recent period (reports from the University Hospital Berne and the University Hospital of Zurich); beside these excellent results, the CABG option seems to be less expensive than PCI with time, since the necessity for additional PCI is rather high following initial PCI, and the price of stent devices is still very high, particularly in Switzerland. Patients, insurance and experts in health care should be better and more honestly informed concerning the risk and costs of PCI and CABG procedures as well as about the much higher rate of subsequent interventions following PCI. Team approach for all patients in whom both options could be offered seems mandatory to avoid unbalanced information of the patients. Looking at the recent developments in transcatheter valve treatments, the revival of cardiological-cardiosurgical conferences seems to a good option to optimize the cooperation between the two medical specialties: cardiology and cardiac surgery.
Resumo:
OBJECTIVE: Cardiac surgery is frequently followed by postoperative delirium, which is associated with increased 1-year mortality, late cognitive deficits, and higher costs. Currently, there are no recommendations for pharmacologic prevention of postoperative delirium. Impaired cholinergic transmission is believed to play an important role in the development of delirium. We tested the hypothesis that prophylactic short-term administration of oral rivastigmine, a cholinesterase inhibitor, reduces the incidence of delirium in elderly patients during the first 6 days after elective cardiac surgery. DESIGN:: Double-blind, randomized, placebo-controlled trial. SETTING: One Swiss University Hospital. PATIENTS: One hundred twenty patients aged 65 or older undergoing elective cardiac surgery with cardiopulmonary bypass. INTERVENTION: Patients were randomly assigned to receive either placebo or 3 doses of 1.5 mg of oral rivastigmine per day starting the evening before surgery and continuing until the evening of the sixth postoperative day. MEASUREMENTS AND MAIN RESULTS: The primary predefined outcome was delirium diagnosed with the Confusion Assessment Method within 6 days postoperatively. Secondary outcome measures were the results of daily Mini-Mental State Examinations and clock drawing tests, and the use of a rescue treatment consisting of haloperidol and/or lorazepam in patients with delirium. Delirium developed in 17 of 57 (30%) and 18 of 56 (32%) patients in the placebo and rivastigmine groups, respectively (p = 0.8). There was no treatment effect on the time course of Mini-Mental State Examinations and clock drawing tests (p = 0.4 and p = 0.8, respectively). There was no significant difference in the number of patients receiving haloperidol (18 of 57 and 17 of 56, p = 0.9) or lorazepam (38 of 57 and 35 of 56, p = 0.6) in the placebo and rivastigmine groups, respectively. CONCLUSION: This negative or, because of methodologic issues, possibly failed trial does not support short-term prophylactic administration of oral rivastigmine to prevent postoperative delirium in elderly patients undergoing elective cardiac surgery with cardiopulmonary bypass.
Resumo:
A 49-year-old male patient presented with a paravalvular leakage 18 years after aortic valve replacement. The patient received a mechanical valve and was weaned uneventfully from cardiopulmonary bypass. After a drop in the pressure curve of the left radial artery an additional line was placed in the proximal ascending aorta showing normal systemic pressure. Transesophageal echocardiography showed a massive circular thrombosis of the distal aortic arch. The patient received a covered stent to expand the residual aortic lumen and left the hospital in good health.
Resumo:
OBJECTIVE: Recent studies have shown that mechanically unloading a failing heart may induce reverse remodeling and functional improvement. However, these benefits may be balanced by an unloading-related remodeling including myocardial atrophy that might lead to decrease in function. Using a model of heterotopic heart transplantation, we aimed to characterize the myocardial changes induced by long-term unloading. MATERIAL AND METHODS: Macroscopic as well as cellular and functional changes were followed in normal hearts unloaded for a 3-month period. Microscopic parameters were evaluated with stereologic methodology. Myocardial contractile function was quantified with a Langendorff isolated, perfused heart technique. RESULTS: Atrophy was macroscopically obvious and accompanied by a 67% reduction of the myocyte volume and a 43% reduction of the interstitial tissue volume, thus accounting for a shift of the myocyte/connective tissue ratio in favor of noncontractile tissue. The absolute number of cardiomyocyte nuclei decreased from 64.7 +/- 5.1 x 10(7) in controls to 22.6 +/- 3.7 x 10(7) (30 days) and 21.6 +/- 3.1 x 10(7) (90 days) after unloading (P < .05). The numeric nucleic density in the unloaded myocardium, as well as the mean cardiomyocyte volume per cardiomyocyte nucleus, remained constant throughout the 90 days of observation. Functional data indicated an increase in ventricular stiffness, although contractile function was preserved, as confirmed by unaltered maximal developed pressure and increased contractility (maximum rate of left ventricular pressure development) and relaxation (minimum rate of left ventricular pressure development). CONCLUSION: Atrophic remodeling involves both the myocyte and interstitial tissue compartment. These data suggest that although there is decreased myocardial volume and increased stiffness, contractile capacity is preserved in the long-term unloaded heart.