Surgery for severe aortic stenosis with low transvalvular gradient and poor left ventricular function – a single centre experience and review of the literature

BACKGROUND: A retrospective comparative study was designed to determine whether the transvalvular gradient has a predictive value in the assessment of operative outcome in patients with severe aortic stenosis and poor left ventricular function. METHODS: From a surgical database, a series of 30 consecutive patients, who underwent isolated aortic valve replacement for severe aortic stenosis with depressed left ventricular (LV) function (EF < 40%), were enrolled in the study and divided into two groups according to the mean transvalvular gradient (TVG): LG(low gradient)-Group < 40 mmHg (n = 13), and HG(high gradient)-Group > 40 mmHg (n = 17). Both groups were then comparatively assessed with respect to perioperative organ functions and mortality. RESULTS: Both groups were well matched with respect to the preoperative clinical status. LG-Group had a larger aortic valve area, higher LVEDP, larger LVESD and LVEDD, and higher mean pulmonary pressures. The immediate postoperative outcome, hospital morbidity and mortality did not differ significantly among the groups. CONCLUSION: In patients with severe aortic stenosis and poor LV function, the mean transvalvular gradient, although corresponds to reduced LV performance, has a limited prognostic value in the assessment of surgical outcome. Generally, operating on this select group of patients is safe

GENERATION OF QUASI-PERPENDIQULARE COLLISIONLESS SHOCKS BY LASER-PRODUCED PLASMA TO SIMULATE THE EFFECTS OF SUPER-COMPRESSION OF THE EARTH MAGNETOSPHERE

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Coronary artery disease progression in patients who need repeat surgical revascularisation: the surgeon's point of view

Objective The purpose of this study was to evaluate changes in native coronary arteries in patients undergoing repeat myocardial revascularisation late (>3 years) after primary coronary artery bypass grafting (CABG). Methods The angiographic images of 30 patients obtained at first and redo CABG were assessed for significant (>75%), short (1 cm) stenosis or total occlusion in native coronary arteries. Bypass grafts were also evaluated for significant stenosis (>50%) or occlusion. Results At first CABG, a mean number of 3.3 grafts/patient (range 1-5) were implanted. The mean time interval from first CABG to reoperation was 11.4 years (range 3-21 years). All patients showed disease progression in the native coronary arteries. At redo CABG, 3 (3.5%) grafts were non-stenotic, 27 (31%) stenotic, and 57 (65.5%) occluded. In native coronary vessels, five patients developed a new left main coronary artery stenosis, and there was a four-to-sixfold increase in total occlusions. Indications for redo CABG were disease progression in non-bypassed vessels (n = 3), bypass lesions (n = 19), and both bypass lesions and disease progression in the distal segments of native coronary arteries (n = 8). Conclusions Late after CABG, coronary artery disease is highly progressive, mainly affecting the proximal segments of native coronary arteries, with a high incidence of coronary occlusion. Conversely, a low incidence of disease progression is observed in the distal segments of native coronary arteries, except in diabetic patients. Total arterial revascularisation as a primary strategy for CABG should be highly recommended, and more aggressive risk factor management is desirable

GENERATION OF QUASI-PERPENDIQULARE COLLISIONLESS SHOCKS BY LASER-PRODUCED PLASMA TO SIMULATE THE EFFECTS OF SUPER-COMPRESSION OF THE EARTH MAGNETOSPHERE

-235-23

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