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Objective: To evaluate the cartilage thickness (ThC) and subchondral bone area (tAB) of the operated and contra-lateral non-operated (healthy) knees in patients with anterior cruciate ligament (ACL)-reconstruction 7 years after surgery using a quantitative and regional cartilage MR imaging (qMRI) technique., Methods: Charts of 410 patients with ACL-reconstructions were retrospectively reviewed. Fifty-two patients (male/female, 28/24; mean age, 33.3 years) were included. Patients underwent KT-1000 testing and qMRI of both knees using coronal fat-saturated 3D spoiled gradient-recalled echo (SPGR) sequences (TR/TE, 44/4 ms) at 1.5 T. Quantitative analyses of ThC and tAB in the femoro-tibial cartilage plates were performed using a subregional approach. In addition, qualitative and quantitative assessment of femoral condyle shapes was performed. t tests with Bonferroni corrections were used for statistical analysis of side-to-side differences between the operated and non-operated knees., Results: KT-1000 testing was abnormal in 3/52 patients (6%). Lateral femoral tAB was significantly lower (-9.2%), and medial tibial tAB was significantly larger (+2%) in the operated vs non-operated knee (P<0.001). Regional and subregional ThC side-to-side differences were less than 0.1mm and, except for the external lateral femoral subregion, they were not statistically significant. Flattened and broader shapes of medial femoral condyles (P<0.001) were found in operated knees. No significant association of presence of cartilage or meniscus lesions at surgery with ThC 7 years post-operatively was found (P=0.06-0.98)., Conclusion: There is evidence for changes in the tAB and femoral shape 7 years post-ACL-reconstruction, but no side-to-side differences in subregional ThC were found between the operated and contra-lateral non-operated knees.

Objective: Methylation of the promoter region of the estrogen receptor gene alpha (ER alpha) occurs as a function of age in human colon, and results in inactivation of gene transcription. In this study, we sought to determine whether such age-related methylation occurs in the cardiovascular system, and whether it is associated with atherosclerotic disease., Methods: We used Southern blot analysis to determine the methylation state of the ER alpha gene in human right atrium, aorta, internal mammary artery, saphenous vein, coronary atherectomy samples, as well as cultured aortic endothelial cells and smooth muscle cells., Results: An age related increase in ER alpha gene methylation occurs in the right atrium (range 6 to 19%, R = 0.36, P < 0.05). Significant levels of ER alpha methylation were detected in both veins and arteries. In addition, ER alpha gene methylation appears to be increased in coronary atherosclerotic plaques when compared to normal proximal aorta (10 +/- 2% versus 4 +/- 1%, P < 0.01). In endothelial cells explanted from human aorta and grown in vitro, ER alpha gene methylation remains low. In contrast, cultured aortic smooth muscle cells contain a high level of ER alpha gene methylation (19-99%)., Conclusions: Methylation associated inactivation of the ER alpha gene in vascular tissue may play a role in atherogenesis and aging of the vascular system. This potentially reversible defect may provide a new target for intervention in heart disease.

Traditional T2-based imaging techniques are geared toward imaging long-T2 species. Traditional techniques are, therefore, not optimal in clinical situations where the information of interest lies in the short-T2 species. T2-selective RF excitation (TELEX) is a technique for obtaining a T2-based contrast that highlights short-T2 values while suppressing long-T2 values-opposite to traditional T2 contrast. Previously, TELEX has been demonstrated qualitatively to highlight only very short-T2 values (T2 approximately 0.001 s). When applied to longer T2 values (T2 > or = 0.01 s), TELEX becomes sensitive to deltaB0 non-uniformities. This restricts its application to problems in which the T2 of interest is very short. In this study, TELEX is characterized quantitatively. Furthermore, a bandwidth broadening scheme is developed that reduces the deltaB0 sensitivity of TELEX. This permits the technique to be applied to longer T2 values. The capabilities and limitations of a practical implementation of TELEX are discussed.

Background: Single or double (limited) coronary artery revascularization using percutaneous transluminal coronary angioplasty (PTCA) and coronary artery bypass (CAB) surgery has recently been enhanced with further innovation in intracoronary stenting and the emergence of minimally invasive direct coronary artery bypass (MIDCAB) grafting. Resource allocation for all modalities is directly dependent on hospitalization costs, length of stay, and clinical results., Methods and Results: Four groups of 25 consecutive patients over 9 months at a single center received either PTCA, stenting, MIDCAB, or conventional CAB for single-vessel coronary disease, primarily of the left anterior descending circulation. Day, supply, and procedural charges were evaluated, along with the total hospital charge. Postprocedural length of stay was calculated and compared with a national database. MIDCAB surgery day charges were less than stenting but greater than PTCA, MIDCAB supply charges were the least of all groups, and MIDCAB procedural charges were less than for conventional CAB. Total charges for MIDCAB grafting were less than for stenting but greater than for PTCA. Postprocedural length of stay for MIDCAB patients was equivalent to PTCA patients and significantly less than for stenting or for conventional CAB., Conclusions: MIDCAB grafting provides a new surgical approach that is comparable in charges to catheter-based interventions. The technique markedly reduces length of stay and perioperative morbidity. The selection of medical or surgical limited coronary revascularization can now be based primarily on clinical outcomes without consideration for associated resource allocation.

Objective: The current study was undertaken to determine long-term results of aortic valve replacement (AVR) in the elderly, to ascertain predictors of poor outcome, and to assess quality of life., Summary Background Data: Aortic valve replacement is the procedure of choice for elderly patients with aortic valve disease. The number of patients aged 70 and older requiring AVR continues to increase. However, controversy exists as to whether surgery devoted to this subset reflect a cost-effective approach to attaining a meaningful quality of life., Methods: This study reviews data on 247 patients aged 70 to 89 years who underwent isolated AVR between 1980 and 1995; there were 126 men (51%) and 121 women (49%). Follow-up was 97% complete (239/247 patients) for a total of 974.9 patient-years. Mean age was 76.2 +/- 4.8 years. Operative mortality and actuarial survival were determined. Patient age, gender, symptoms, associated diseases, prior conditions, New York Health Association class congestive heart failure, native valve disease, prosthetic valve type, preoperative catheterization data, and early postoperative conditions were analyzed as possible predictors of outcome. Functional recovery was evaluated using the SF-36 quality assessment tool., Results: Operative mortality was 6.1% (15/247). Multivariate logistic regression showed that poor left ventricular function and preoperative pacemaker insertion were independent predictors of early mortality. After surgery, infection was predictive of early mortality. Overall actuarial survival at 1, 5, and 10 years was 89.5 +/- 2% (198 patients at risk), 69.3 +/- 3.4% (89 patients at risk), and 41.2 +/- 6% (13 patients at risk), respectively. Cox proportional hazards model showed that chronic obstructive pulmonary disease and urgency of operation were independent predictors of poor long-term survival. Postoperative renal failure also was predictive of poor outcome. Using the SF-36 quality assessment tool, elderly patients who underwent AVR scored comparably to their age-matched population norms in seven of eight dimensions of overall health. The exception is mental health., Conclusions: Aortic valve replacement in the elderly can be performed with acceptable mortality. Significant preoperative risk factors for early mortality include poor left ventricular function and preoperative pacemaker insertion. Predictors of late mortality include chronic obstructive pulmonary disease and urgency of operation. These results stress the importance of operating on the elderly with aortic valve disease; both long-term survival and functional recovery are excellent.

Background: Many centers advocate bioprosthetic valves in the elderly to avoid anticoagulation, in particular when patient survival is less than the expected valve durability. Because expected survival in the elderly is increasing and age-specific risk of anticoagulation in the elderly is not known, we examined valve- and anticoagulation-related morbidity in elderly patients after aortic valve replacement (AVR) with bioprostheses or mechanical prostheses., Methods and Results: Between January 1980 and June 1994, 211 patients age > or = 70 years underwent isolated AVR; there were 109 men (52%) and 102 women (48%). Mean age was 75.9 +/- 4.8 years. Aortic stenosis was present in 194 (92%) patients. Bioprostheses were used in 145 (69%) and mechanical prostheses were used in 66 (31%). Chronic anticoagulation was maintained in all patients with a mechanical valve and in 18 patients (12%) with a bioprosthetic valve. Follow-up data were obtained for 98% (194 of 197) of hospital survivors at a mean follow-up of 3.8 years. Operative mortality was 6.6%; survival at 3 and 5 years was 75.3 +/- 3% and 64.6 +/- 4%, respectively. There was no significant difference in operative or late mortality between patient groups. Rates of freedom from thromboembolic events, endocarditis and anticoagulant-related hemorrhage for bioprosthetic and mechanical valve patients were similar. Prosthetic failure was identified in three bioprosthetic valves (2%); furthermore, the 4 patients in the series who required reoperation had received bioprostheses at the first operation., Conclusions: In conclusion, (1) elderly patients undergoing isolated AVR can be managed with either mechanical or bioprosthetic valves with similar early and late risk, as long as there are no specific contraindications to anticoagulation; (2) anticoagulation-related risk of hemorrhage is low in this group of elderly patients; and (3) the low but significant risk of reoperation following the use of bioprostheses suggests that mechanical valves may be underused in the elderly.

Background: The Perma-Flow prosthetic coronary graft is a 5-mm polytetrafluoroethylene tube into which is incorporated a Venturi flow restrictor. An aorto-superior vena caval fistula is created and coronary anastomoses are constructed proximal to the resistor in side-to-side fashion, where arterial pressure is maintained. From November 1992 through December 1995, eight investigational centers in North America have implanted this graft in 40 patients with inadequate autologous alternatives., Methods: Patients were selected for inclusion in this study if coronary artery bypass grafting was required and adequate autologous conduit to complete revascularization was not available. Operative data were completed by the implantating surgeon and referred to a central center, the Minneapolis Heart Institute, for correlation. Follow-up was conducted by data coordinators at each institution, and follow-up data were obtained directly from these coordinators for inclusion in the study., Results: Patient age ranged from 53 to 82 years, and 15 patients were undergoing reoperations (38%). On each Perma-Flow graft one to four coronary side-to-side anastomoses were constructed. In addition, left internal mammary artery (n = 26), greater saphenous vein (8), right internal mammary artery (4), and gastroepiploic artery (4) were used to complete revascularization. Aortic (2) or mitral valve replacement (1) was also carried out. There were seven operative deaths (18%) and two late deaths (4 and 6 months). After 1 to 37 months (mean, 13 +/- 9 months) of follow-up, 29 of 31 surviving patients are asymptomatic. Echocardiographic heart size has not increased from the postoperative value, indicating limited volume load has not affected heart size. Protocol catheterization (n = 32) in 28 patients 1 week to 1 year postoperatively revealed 7 of 73 studied coronary anastomoses (9.5%) and two distal extensions and resistors were occluded (7%). In 1 patient during sternal debridement at 1 year, no flow was found in the graft., Conclusions: The Perma-Flow graft is a useful adjunct to complete revascularization in patients with deficient autologous conduit.