Effective height,which represents the height difference between the central free margins and the aortic insertion lines can be easily determined by 2-D echocardiography and allows for identification of prolapse in the native cusps and assessment of prolapse correction after valve repair.Nonetheless,it allows to see only two of three aortic valve(AV)coaptation planes and this may lead to misunderstanding of the underlying pathophysiological mechanism for aortic regurgitation and hence in unsuccessful repair.In contrast,3D transoesophageal echocardiography and multiple plane reconstruction lets visualize all the three coaptation planes between the AV cusps and it represents an invaluable tool in the assessment of aortic valve geometry.It is highly recommendable before AV repair to accurately study the complex three dimensional cusps anatomy and their geometric interrelation with aortic root. 相似文献
We present the case of a young woman corrected with a Mustard procedure undergoing successful transvenous double chamber pacemaker implantation with the atrial lead placed in the systemic venous channel. The case presented demonstrates that, when the systemic venous atrium is separate from the left atrial appendage, the lead can be easily and safely placed in the systemic venous left atrium gaining satisfactory sensing and pacing thresholds despite consisting partially of pericardial tissue. 相似文献
The intra-aortic balloon pump (IABP) is used worldwide as an anti-ischemic strategy and to reduce myocardial workload. However, whether IABP augments coronary flow after coronary bypass via a passive increase in diastolic pressure or an active response of the coronary bed remains uncertain.
Methods
We analyzed transit-time flow measurements and the contemporary changes in coronary resistances obtained during 1:1 IABP and during its cessation in 144 consecutive patients receiving prophylactic IABP before isolated coronary artery bypass grafting (n = 340 graft segments).
Results
Normally functioning grafts showed lower coronary resistances, greater percentage decrease in resistance, and greater increases in average maximum diastolic and mean flow during 1:1 IABP compared with IABP cessation (P < .001). Arterial and sequential saphenous vein grafts showed better flowmetry and greater reductions in coronary resistances compared with single venous grafts. Accordingly, graft flow reserve (defined as mean flow during 1:1 IABP/mean flow with IABP off) was recruited (graft flow reserve > 1) during 1:1 IABP in all normally functioning grafts, with higher values in single arterial or sequential saphenous vein grafts than in single venous grafts (both P < .001). Coronary resistances were higher in 7 failed grafts versus normal-functioning grafts at baseline; these did not decrease during 1:1 IABP and showed worse transit-time flow results.
Conclusions
IABP recruits graft flow reserve by lowering coronary resistance in functioning grafts. Arterial and sequential venous grafts showed greater reduction in coronary resistance compared with single saphenous grafts. 相似文献
BackgroundReactive microgliosis, hallmark of neuroinflammation, may contribute to neuronal degeneration, as shown in several neurodegenerative diseases. We in vivo evaluated microglia activation in early dementia with Lewy bodies, still not reported, and compared with early Parkinson's disease, to assess possible differential pathological patterns.MethodsWe measured the [11C]-PK11195 binding potentials with Positron Emission Tomography, using a simplified reference tissue model, as marker of microglia activation, and cerebral spinal fluid protein carbonylation levels, as marker of oxidative stress. Six dementia with Lewy bodies and 6 Parkinson's disease patients within a year from the onset, and eleven healthy controls were included. Clinical diagnosis was confirmed at a 4-year follow-up.ResultsIn dementia with Lewy bodies as well as in Parkinson's disease, we found significant (p < 0.001) [11C]-PK11195 binding potential increases in the substantia nigra and putamen. Patients with Lewy bodies dementia had extensive additional microglia activation in several associative cortices. This was evident also at a single subject level. Significant increase of Cerebral Spinal Fluid protein carbonylation was shown in both patients' groups.Conclusions[11C]-PK11195 Positron Emission Tomography imaging revealed neuroinflammation in dementia with Lewy bodies and Parkinson's disease, mirroring, even at a single subject level, the common and the different topographical distribution of neuropathological changes, yet in the earliest stages of the disease process. Focusing on those events that characterize parkinsonisms and Parkinson's disease may be the key to further advancing the understanding of pathogenesis and to taking these mechanisms forward as a means of defining targets for neuroprotection. 相似文献
To make an in vitro evaluation of the lesion size and depth produced in two different sets of radio frequency energy bipolar delivery: simultaneous biparietal bipolar (SBB) and simultaneous uniparietal bipolar (SUB).
Methods
Two separate prototypes have been built for our purpose: one to be used in SBB mode and the other to be used SUB mode. Forty left atrium samples were taken from the hearts of freshly slaughtered pigs. They were ablated into a simulator ABLABOX, where blood flow, temperature, and contact force were controlled. After being sliced into a cryotome, the samples were digitalized by a flatbed scanner, and the images were analyzed by a computer morphometric software.
Results
Transmural lesions were achieved in 18/20 samples (90%) in SBB, while SUB showed transmurality in 9/20 samples (45%). Overall maximum diameter (DMAX) resulted larger in SUB than in SBB (2.43?±?0.30 mm, 1.62?±?0.14 mm, respectively; p?<?0.05): Moreover, maximum epicardial and endocardial diameters (DEPI and DENDO, respectively) were wider in SUB group than SBB group (2.28?±?0.30 mm, 2.26?±?0.40 and 1.60?±?0.14 mm, 1.59?±?0.15 mm, respectively; p?<?0.05). We observed the same tendency in lesion depth: The total area and volume (ATOT and VTOT) were broader in SUB group than in SBB one (581.01?±?65.38 mm/mm2, 58.10?±?6.53 mm/mm3 and 521.97?±?73.05 mm/mm2, 52.19?±?7.30 mm/mm3. respectively; p?<?0.05).
Conclusions
In contrast with the smaller lesion sizes, the biparietal bipolar group showed a higher transmurality rate. These findings may suggest a better drive of the energy flow when compared with SUB lesions.
BACKGROUND: Recombinant activated factor VII (rFVIIa) has been increasingly used to stop life-threatening bleeding following cardiac operations. Nonetheless, the issue of dosing, given the expense and potential for thrombotic complications, is still of major concern. We report our experience with small-dose rFVIIa in patients with refractory bleeding after cardiac surgery. METHODS AND RESULTS: From September 2005 to June 2007, 40 patients (mean age 70.1+/-9.2 years, 52.5 males) received a low dose of rFVIIa (median: 18 microg/kg, interquartile range: 9-16 microg/kg) for refractory bleeding after cardiac surgery. Forty propensity score-based greedy matched controls were compared to the study group. Low dose of rFVIIa significantly reduced the 24-h blood loss: 1610 ml [ 1285-1800 ml] versus 3171 ml [2725-3760 ml] in the study and control groups, respectively (p<0.001). Thus, hourly bleeding was 51.1 ml [34.7-65.4 ml] in patients receiving rFVIIa and 196.2 ml/h [142.1-202.9 ml] in controls (p<0.001). Furthermore, patients receiving rFVIIa showed a lower length of stay in the intensive care unit (p<0.001) and shorter mechanical ventilation time (p<0.001). In addition, the use of rFVIIa was associated with reduction of transfusion requirements of red blood cells, fresh frozen plasma and platelets (all, p<0.001). Finally, treated patients showed improved hemostasis with rapid normalization of coagulation variables (partial thromboplastin time, international normalized ratio, platelet count, p<0.001). In contrast, activated prothrombin time and fibrinogen did not differ between groups (p=ns). No thromboembolic-related event was detected in our cohort. CONCLUSIONS: In our experience low-dose rFVIIa was associated with reduced blood loss, improvement of coagulation variables and decreased need for transfusions. Our findings need to be confirmed by further larger studies. 相似文献