1/31. Living related donor liver transplantation in a patient with severe aortic stenosis.We report the successful anaesthetic management of a young girl with Alagille's syndrome and severe aortic stenosis (resting pressure gradient 88 mm Hg) undergoing living related donor liver transplantation (LRDLT). The patient had end-stage liver disease and LRDLT was performed before replacement of the aortic valve. Anaesthesia was conducted uneventfully with the aid of a pulmonary artery catheter. intra-aortic balloon pumping was used in the perioperative period for protection against myocardial ischaemia. Total clamping of the inferior vena cava was avoided during surgery and volume administration was guided by the pulmonary artery pressure. A stable circulation was maintained in the reperfusion period. The patient was discharged from hospital on day 54 after operation with normal liver function. Two years later her aortic valve was replaced successfully.- - - - - - - - - - ranking = 1keywords = volume (Clic here for more details about this article) |
2/31. Recombinant hirudin anticoagulation for aortic valve replacement in heparin-induced thrombocytopenia.PURPOSE: To report the case of a patient with HIT that received a prolonged infusion of r-hirudin (lepirudin; Refludan; Hoechst, france) before, during and after cardiopulmonary bypass (CPB) for aortic surgery. Although administration of r-hirudin for CPB anticoagulation has previously been reported, many questions persist concerning the best therapeutic regimen for CPB anticoagulation as well as the time of onset and the doses for postoperative anticoagulation. CLINICAL FEATURES: A 65-yr-old man was admitted for surgery of aortic stenosis after an episode of acute pulmonary edema complicated by deep venous thrombosis in the context of documented HIT. The patient received r-hirudin for 13 dy before surgery at doses (0.4 mg x kg(-1) bolus followed by 0.15 mg x kg(-1) x hr(-1) continuous infusion) that maintained activated partial thromboplastin time (aPTT) ratios between 2 and 2.5. Anticoagulation for CPB was performed with r-hirudin given as 0.1 mg x kg(-1) i.v. bolus and 0.2 mg kg(-1) in the CPB priming volume. Anticoagulation during CPB was monitored with the whole blood activated coagulation time and ecarin clotting time (ECT) performed in the operating room with values corresponding to r-hirudin concentrations >5 microg x ml(-1) during CPB. Anticoagulation during CPB was uneventful. Two bleeding episodes, related to the r-hirudin regimen and necessitating allogeneic blood transfusion, occurred after surgery. CONCLUSION: This case report confirms previous experience of the use of r-hirudin for anticoagulation during CPB and provides additional information in the context of prolonged r-hirudin infusion before and after CPB.- - - - - - - - - - ranking = 1keywords = volume (Clic here for more details about this article) |
3/31. Homograft pulmonic stenosis after the Ross procedure: evaluation of the stenotic valve area by proximal isovelocity surface area (PISA).The proximal isovelocity surface area (PISA) technique has been used to evaluate valvular regurgitant flow, regurgitant orifice area, and stenotic valve area. This report shows the usefulness of this Doppler technique in quantifying the stenotic valve area of a pulmonic valve homograft prosthesis after the Ross procedure. The patient was a 35-year-old man who had a Ross procedure 3 years earlier for aortic stenosis, which included replacement of the pulmonic valve with a cryopreserved homograft pulmonic valve. With an aliasing velocity set at 40 cm/s and a PISA radius of 1.1 cm, the pulmonic valve area was calculated as follows: Pulmonic valve peak flow rate = 2 x3.14 x1.12 x40 = 304 mL/s; Pulmonic valve area = Peak flow rate / Peak velocity = 284/350 = 0.87 cm2.- - - - - - - - - - ranking = 116.82034786639keywords = reserve (Clic here for more details about this article) |
4/31. Aortic valve replacement combined with endoventricular circulatory patch plasty (Dor operation) in a patient with aortic valve stenosis and severe ischemic cardiomyopathy.A 58-year-old woman with ischemic cardiomyopathy and aortic valve stenosis, underwent aortic valve replacement and simultaneous endoventricular circulatory patch plasty (Dor operation). She underwent coronary artery bypass grafting for severe triple vessel disease 10 years ago. Recently she started to show severe congestive heart failure. aortic valve stenosis with pressure gradient of 85-mmHg was also found. Coronary bypasses were all patent, but the left ventricle (LV) was severely dilated (LVDd/Ds=71/61 mm) and the ischemic cardiomyopathy was considered as the cause. She successfully underwent aortic valve replacement and endoventricular circulatory patch plasty. The initial postoperative course was complicated with intractable ventricular arrhythmia, but subsequent course was smooth and the patient was discharged with improved symptoms (NYHA Class II). Postoperative catheterization showed decreased left ventricular volume and improved contractility. This case implies the role of LV remodeling procedure in the ischemic cardiomyopathy combined with aortic valve lesion- - - - - - - - - - ranking = 1keywords = volume (Clic here for more details about this article) |
5/31. microvascular angina in a patient with aortic stenosis.A 39-year-old woman had exercise-induced ST segment depression associated with chest pain. Cardiac evaluation revealed moderate aortic stenosis (AS), related to the bicuspid valves, with an aortic mean pressure gradient of 22 mmHg, a calculated aortic valve area of 1.3 cm2 and normal left ventricular (LV) peak systolic and end-diastolic pressures, but no LV hypertrophy, resulting in normal LV wall stress. Although the coronary arteries were angiographically normal, rapid atrial pacing and an intracoronary papaverine injection revealed a significantly decreased coronary flow reserve (CFR), which may have played an important role in the pathogenesis of angina pectoris in this patient. Though the CFR is usually decreased in patients with AS, as well as in microvascular angina, in this particular case, it appeared to have decreased as a consequence of microvascular dysfunction rather than of AS-related mechanisms.- - - - - - - - - - ranking = 116.82034786639keywords = reserve (Clic here for more details about this article) |
6/31. Mechanisms of coronary microcirculatory dysfunction in patients with aortic stenosis and angiographically normal coronary arteries.BACKGROUND: Development of left ventricular hypertrophy in aortic stenosis (AS) is accompanied by coronary microcirculatory dysfunction, demonstrated by an impaired coronary vasodilator reserve (CVR). However, evidence for regional abnormalities in myocardial blood flow (MBF) and the potential mechanisms is limited. The aims of this study were to quantitatively demonstrate differences in subendocardial and subepicardial microcirculation and to investigate the relative contribution of myocyte hypertrophy, hemodynamic load, severity of AS, and coronary perfusion to impairment in microcirculatory function. methods AND RESULTS: Twenty patients with isolated moderate to severe AS were studied using echocardiography to assess severity of AS, cardiovascular magnetic resonance to measure left ventricular mass (LVM), and PET to quantify resting and hyperemic (dipyridamole 0.56 mg/kg) MBF and CVR in both the subendocardium and subepicardium. In the patients with most severe AS (n=15), the subendocardial to subepicardial MBF ratio decreased from 1.14 /-7 at rest to 0.92 /-7 during hyperemia (P<0.005), and subendocardial CVR (1.43 /-3) was lower than subepicardial CVR (1.78 /-35; P=0.01). Resting total LV blood flow was linearly related to LVM, whereas CVR was not. Increase of total LV blood flow during hyperemia (mean value, 89.6 /-6%; range, 17% to 233%) was linearly related to aortic valve area. The decrease in CVR was related to severity of AS, increase in hemodynamic load, and reduction in diastolic perfusion time, particularly in the subendocardium. CONCLUSIONS: CVR was more severely impaired in the subendocardium in patients with LVH attributable to severe AS. Severity of impairment was related to aortic valve area, hemodynamic load imposed, and diastolic perfusion rather than to LVM.- - - - - - - - - - ranking = 116.82034786639keywords = reserve (Clic here for more details about this article) |
7/31. Hemodynamic changes following correction of severe aortic stenosis using the Cutter-Smeloff prosthesis.Twelve patients with pure or dominant stenosis were studied before and after aortic valve replacement (Cutter-Smeloff). The changes in cardiac output and A-V O2 difference were small and insignificant, but exercise stroke volume increased from 72 to 96 ml after the surgery. The aortic peak systolic gradient was 92 /- 29 mm Hg before and 4 /- 9.8 mm Hg after surgery. The PA wedge pressure, taken as a measure of the LV diastolic pressure, decreased from 18 mm Hg to 12 mm Hg at rest and 30 mm Hg to 16 mm Hg on exercise. The PA pressures also decreased from 37/18 (mean, 26) to 28/11 (17) mm Hg at rest, and 61/31 (43) to 41/17 (27) mm Hg on exercise, but the PA and PA wedge pressures maintained their tendency to increase in a linear manner with oxygen consumption (Vo2) on exercise after surgery. As a result of decreased wedge pressure, the pulmonary vascular resistance also decreased significantly afterward. The adequacy of cardiac output at rest and on exercise expressed by cardiac output as the linear function of Vo2 improved toward the normal (values before operation, CO = 2.78 0.0069 Vo2, r = 0.84; after operation, CO = 3.80 0.0062 Vo2, r = 0.91). The exercise factor (delta CO/delta Vo2) or the regression coefficient, however, was similar before and after surgery. The hemodynamic result was satisfactory although some abnormalities of the left ventricular function persisted after operation.- - - - - - - - - - ranking = 1keywords = volume (Clic here for more details about this article) |
8/31. Ross operation with a tissue-engineered heart valve.BACKGROUND: The Ross procedure has gained increasing acceptance due to excellent hemodynamic results by replacing the diseased aortic valve with the viable autologous pulmonary valve. Consequently, the right ventricular outflow tract (RVOT) has to be reconstructed. In this report a viable heart valve was created from decellularized cryopreserved pulmonary allograft that was seeded with viable autologous vascular endothelial cells (AVEC). methods: A 43-year-old patient suffering from aortic valve stenosis underwent a Ross operation on May 20, 2000, using a tissue engineered (TE) pulmonary allograft to reconstruct the RVOT. Four weeks before the operation a piece of forearm vein was harvested to separate, culture, and characterize AVEC. Follow-up was completed at discharge, 3, 6, and 12 months postoperatively by clinical evaluation, transthoracic echocardiography (TTE), and magnetic resonance imaging (MRI). Additionally, at 1-year follow-up a multislice computed tomographic scan was performed. RESULTS: After four weeks of culturing 8.34 x 10(6) AVEC were available to seed a 27-mm decellularized pulmonary allograft. trypan blue staining confirmed 96.0% viability. Reendothelialization rate after seeding was 9.0 x 10(5) cells/cm2. TTE and MRI revealed excellent hemodynamic function of the TE heart valve and the neoaortic valve as well. Multislice computed tomography revealed no evidence of valvular calcification. CONCLUSIONS: After 1 year of follow-up the patient is in excellent condition without limitation and exhibits normal aortic and pulmonary valve function.- - - - - - - - - - ranking = 116.82034786639keywords = reserve (Clic here for more details about this article) |
9/31. Effects of balloon valvuloplasty on left anterior descending coronary artery blood flow in a neonate with critical aortic stenosis with transthoracic doppler echocardiography.Doppler echocardiography has recently been used in the assessment of coronary flow dynamics. We described the application of transthoracic Doppler echocardiography for the measurement of the coronary flow before and after balloon valvuloplasty in a neonate with critical aortic stenosis. In this case, coronary flow volume/left ventricular mass ratio increased after the procedure, suggesting the improvement of myocardial blood perfusion. Thus, this technique may provide additional information about coronary flow dynamics in patients with critical aortic stenosis.- - - - - - - - - - ranking = 1keywords = volume (Clic here for more details about this article) |
10/31. Aortic root abscess with aortico-mitral discontinuity after a ross operation in a child: reconstruction with an oversized homograft.A case of early neo-aortic root abscess following a Ross operation in a 3(1/2)-year-old child is described. The infection destroyed neo-aortic wall with two of the semilunar leaflets detached, and the abscess cavity extended across the intervalvular fibrous body into the left atrium and onto the native mitral valve creating partial "aortico-mitral discontinuity." Reconstruction was successful with an oversized cryopreserved homograft.- - - - - - - - - - ranking = 116.82034786639keywords = reserve (Clic here for more details about this article) |
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