Arterial distensibility as a possible compensatory mechanism in chronic aortic insufficiency.
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OBJECTIVE: To evaluate elastic properties of conduit arteries in asymptomatic patients who have severe chronic aortic regurgitation. METHODS: Twelve healthy volunteers aged 30+/-1 years (control group) and 14 asymptomatic patients with severe aortic regurgitation aged 29+/-2 years and left ventricular ejection fraction of 0.61+/-0.02 (radioisotope ventriculography) were studied. High-resolution ultrasonography was performed to measure the systolic and diastolic diameters of the common carotid artery. Simultaneous measurement of blood pressure enabled the calculation of arterial compliance and distensibility. RESULTS: No differences were observed between patients with aortic regurgitation and the control group concerning age, sex, body surface, and mean blood pressure. Pulse pressure was significantly higher in the aortic regurgitation group compared with that in the control group (78+/-3 versus 48+/-1mmHg, P<0.01). Arterial compliance and distensibility were significantly greater in the aortic regurgitation group compared with that in the control group (11.0+/-0.8 versus 8.1+/-0.7 10(-10) N-1 m4, P=0.01 e and 39.3+/-2.6 versus 31.1+/-2.0 10(-6) N-1 m2, P=0.02, respectively). CONCLUSION: Patients with chronic aortic regurgitation have increased arterial distensibility. Greater vascular compliance, to lessen the impact of systolic volume ejected into conduit arteries, represents a compensatory mechanism in left ventricular and arterial system coupling. (+info)
Echocardiographic assessment of severity of aortic regurgitation.
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An echocardiographic study of left ventricular diameter was made in 27 patients with aortic regurgitation. Comparison was made with a group of 21 normal subjects and a group of 6 patients with large left ventricles without valvar regurgitation. Total stroke volume, total left ventricular output, and ejection fraction were derived by the method of cubing the left ventricular diameter to give approximate left ventricular volumes at and-diastole and end-systole. The patients were assessed independently and placed into three grades of severity. The eechocardiographic dimensions of patients with mild aortic regurgitation were not significantly different from those of the normal subjects. With increasing severity of aortic regurgitation, there were increases in group values for left ventricular diameter, total stroke volume, and total left ventricular output. The ejection fraction was depressed below the normal range in only one patient with aortic regurgitation. It is concluded that echocardiographic measurement of left ventribular dimensions is of value in assessing the severity of aortic regurgitation. (+info)
Incidence, location, pathology, and significance of pulmonary homograft stenosis after the Ross operation.
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BACKGROUND: The Ross operation has several theoretical advantages. However, concern exists regarding evolving pathology in the pulmonary homograft. METHODS AND RESULTS: Consecutive patients (n=144; mean age 31 years, range 2 months to 64 years) undergoing the Ross operation were studied between 1993 and 2000. Echocardiographic examination of the pulmonary homograft was performed immediately after surgery, then at yearly intervals for a mean interval of 48 months. Fifteen patients (mean age 37 years) in whom echocardiography revealed peak pulmonary gradients >/=30 mm Hg (mean 46+/-18 mm Hg) underwent MRI with velocity mapping in a Picker 1.5-T magnet. No patient had more than mild pulmonary regurgitation. Four patients required reoperation for rapidly progressive pulmonary homograft stenosis; in all 4, there was macroscopic and microscopic evidence of a pronounced chronic adventitial reaction, with perivascular infiltration producing extrinsic compression. Freedom from any pulmonary homograft stenosis at 7-year follow-up was 79.7%, with instantaneous hazard falling to zero after 4 years. Freedom from reoperation at 7 years was 96.7%. In those studied with MRI, there was evidence of narrowing of the whole homograft or distal suture line in 14 of 15 patients, with obvious excess surrounding tissue in 11. Mean minimum diameter and peak velocity by MRI were 11+/-2 mm and 3.2+/-0.7 m/s, respectively. Multivariate analysis of patient-, surgery-, and homograft-related variables did not reveal any significant risk factors for development of neopulmonary stenosis. CONCLUSIONS: Pulmonary homograft stenosis after the Ross operation is clinically important and appears to represent an early postoperative inflammatory reaction to the pulmonary homograft that leads to extrinsic compression and/or shrinkage. (+info)
Time course of aortic valve function and root dimensions after subcoronary ross procedure for bicuspid versus tricuspid aortic valve disease.
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BACKGROUND: The freestanding aortic root, which is the currently preferred operative technique for pulmonary autografts, is reported to dilate and potentially promote aortic insufficiency, which has led to a controversial debate on the appropriate surgical technique, especially for congenital bicuspid aortic valve disease. Desirable data on the time course of valve function and root dimensions for the alternative subcoronary technique comparing bicuspid and tricuspid aortic valve disease are scarce. METHODS AND RESULTS: Echocardiographic examinations of 31 patients with congenital bicuspid aortic valve disease (group A; age 50.5+/-11.0 years) and 51 patients with acquired tricuspid aortic valve disease (group B; age 48.1+/-15.7 years) who were operated on between June 1994 and August 1998 were performed twice postoperatively. At first and second follow-up, respectively, maximum (mean) pressure gradients were 6.0+/-2.0 (3.6+/-1.0) and 5.1+/-2.1 (2.9+/-1.1) mm Hg in group A and 6.5+/-3.5 (3.9+/-1.9) and 5.0+/-1.7 (2.9+/-1.0) mm Hg in group B (P>0.05 between groups). In group A, grade 0 aortic insufficiency at first and second follow-up occurred in 8 and 7 patients, respectively, grade 0-I in 12 and 9 patients, grade I in 9 and 11 patients, grade I-II in 1 and 0 patients, and grade II in 1 and 4 patients; in group B, grade 0 aortic insufficiency occurred in 16 and 18 patients, grade 0-I in 16 and 8 patients, grade I in 17 and 21 patients, grade I-II in 0 and 1 patient, and grade II in 0 and 1 patient (P>0.05). Aortic insufficiency decreased in 10 patients (17%). However, there was an overall tendency for aortic insufficiency to increase over time (n=23, 38%), although it remained subclinical. Aortic root dimensions did not differ between groups and were constant during follow-up. CONCLUSIONS: This study provides some evidence that the function of the subcoronary pulmonary autograft in bicuspid aortic valve disease is excellent, with stable root dimensions, and is not different from that of tricuspid aortic valves at least up to 5.5 years postoperatively, which suggests the subcoronary technique should be reconsidered. (+info)
Late outcome after arterial switch operation for transposition of the great arteries.
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BACKGROUND: Early and midterm results of the arterial switch operation (ASO) in transposition of the great arteries (TGA) are good, but late outcome data in large populations are still few. METHODS AND RESULTS: Twelve hundred patients had an ASO for TGA between 1982 and 1999, with prospective follow-up of 1095 survivors. Outcome measures included late death, reoperation, aortic insufficiency (AI), pulmonary stenosis (PS), and coronary anomaly. Median follow-up was 4.9 years (range 0.5 to 17 years). Late death occurred in 32 patients; survival was 88% at both 10 and 15 years. The hazard function for death declined rapidly, with no deaths after 5 years. Late mortality was correlated with reintervention and major events in the intensive care unit. Reoperation was performed in 103 patients, more often in complex TGA; the cause was mainly PS. Freedom from reintervention was 82% at 10 and 15 years, with a hazard function that declined rapidly but slowly increased after 3 years. At the last follow-up, PS was present in 3.9% of patients, and grade II or more AI was present in 3.2%, with a cumulative incidence of 9% at 15 years. Among the 278 patients who had a coronary arteriography, 8% had coronary lesions. Normal left ventricle and sinus rhythm were seen in 96.4% and 98.1%, respectively. CONCLUSIONS: Fifteen years after ASO, late mortality was low, with no deaths after 5 years; reoperation, mainly owing to PS, occurred throughout the follow-up. AI and coronary obstruction are rare but warrant further follow-up. Good left ventricular function and sinus rhythm are maintained. (+info)
Are outcomes of surgical versus transcatheter balloon valvotomy equivalent in neonatal critical aortic stenosis?
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BACKGROUND: For neonates with critical aortic valve stenosis who are selected for biventricular repair, valvotomy can be achieved surgically (SAV) or by transcatheter balloon dilation (BAV). METHODS AND RESULTS: Data regarding 110 neonates with critical aortic valve stenosis were evaluated in a study by the Congenital Heart Surgeons Society from 1994 to 1999. Reduced left ventricular function was present in 46% of neonates. The initial procedure was SAV in 28 patients and BAV in 82 patients. Mean percent reduction in systolic gradient was significantly greater with BAV (65+/-17%) than SAV (41+/-32%; P<0.001). Higher residual median gradients were present in the SAV versus BAV group (36 mm Hg [range, 10 to 85 mm Hg] versus 20 mm Hg [0 to 85 mm Hg], P<0.001). Important aortic regurgitation was more often present after BAV (18%) than SAV (3%; P=0.07). Time-related survival after valvotomy was 82% at 1 month and 72% at 5 years, with no significant difference for SAV versus BAV, even after adjustment for differences in patient and disease characteristics. Independent risk factors for mortality were mechanical ventilation before valvotomy, smaller aortic valve annulus (z score), smaller aortic diameter at the sinotubular junction (z score), and a smaller subaortic region. A second procedure was performed in 46 survivors. Estimates for freedom from reintervention were 91% at 1 month and 48% at 5 years after the initial valvotomy and did not differ significantly between groups. CONCLUSIONS: SAV and BAV for neonatal critical aortic stenosis have similar outcomes. There is a greater likelihood of important aortic regurgitation with BAV and of residual stenosis with SAV. (+info)
Evaluation of St. Jude Medical valve's long-term function by Doppler echocardiography.
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In this study, the long-term function of St. Jude Medical valve (SJM valve) is evaluated by Doppler echocardiography. The subjects were 191 patients who underwent mitral or aortic valve replacement using SJM valve in our institute since July 1978 and had no clinical problem showing more than 50% of left ventricular ejection fraction. The patients were classified into 3 groups according to measurement period (within 5 years, 10 years and 15 years and more), and further classified by size and their results were compared. In every group by size, there was no significant difference among groups by measurement period. In the mitral valve position, peak pressure gradient and pressure half-time were not significantly different among groups by size. On the other hand, in the aortic valve position, pressure gradient in 21-mm group was significantly high among 21-mm, 25-mm, and 27-mm groups, showing a negative correlation with size. As the result, it was suggested that SJM valve kept a good function more than 15 years after operation. From these results, it was considered that the patients with small annlus of the aortic valve needed annulus-enlarging procedure or use of Hemodynamic Plus series valves to keep the size of more than 23 mm. (+info)
Current medical management of valvular heart disease.
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Drug therapy plays a key role in the management of valvular heart disease, though in many cases it does not alter its course or delay the need for surgery. The importance of drug therapy lies in stabilizing the patient's condition when the disease is due to abnormal valve structure, and in treating the underlying condition when the condition is due to a functional abnormality. Drug therapy also lowers the risk of bacterial endocarditis and rheumatic fever. (+info)