Reoperations in patients with patent left internal mammary artery.

In the past decade the rate of reoperative coronary bypass grafting has averaged 8%. In these patients adequate myocardial protection is often difficult because delivery of cardioplegia is frequently suboptimal when the internal mammary artery graft is patent. We describe a simple technique for performing cardiac reoperation in patients with a patent left internal mammary artery graft through a balloon catheter used for angioplasty and positioned in the left internal mammary artery graft. Our study included 3 patients and there were no operative deaths and complications.     

Analysis of U2 Small Nuclear RNA Fragments in the Bile Differentiates Cholangiocarcinoma from Primary Sclerosing Cholangitis and Other Benign Biliary Disorders

Background and Objectives

Up to now the diagnosis of early stage cholangiocarcinoma (CC) has remained difficult, with low sensitivities reported for current diagnostic methods. Based on recent promising findings about circulating U2 small nuclear RNA fragments (RNU2-1f) as novel blood-based biomarkers for pancreatic and colorectal adenocarcinoma, we studied the utility of RNU2-1f as a diagnostic marker of CC in bile fluid.

Methods

Bile fluid was collected from patients with CC (n = 12), controls (patients with choledocholithiasis) (n = 11) and with primary sclerosing cholangitis (PSC; n = 11). RNU2-1f levels were measured by real-time polymerase chain reaction normalized to cel-54.

Results

Measurement of RNU2-1f levels in bile fluids enabled the differentiation of patients with CC from controls in all cases. Furthermore, RNU2-1f levels in bile fluids of patients with CC were significantly higher than in patients with PSC, resulting in a receiver-operating characteristic curve area of 0.856, with sensitivity of 67 % and specificity of 91 %.

Conclusions

Our data suggest that the measurement of RNU2-1 fragments detected in the bile fluid can be used as a diagnostic marker for CC and should be included in future prospective diagnostic studies for this disease entity.     

Cardiac troponin I concentrations during on-pump coronary artery surgery

Perioperative myocardial infarction remains a frequent complication after coronary artery bypass grafting, and is associated with a poor prognosis. This retrospective study compared cardiac troponin I concentrations after on-pump bypass grafting in 2 groups of patients: 100 operated on using a single-clamp technique to perform anastomoses, and 80 operated on using a double-clamp technique. Postoperative cardiac troponin I levels were not significantly different between groups. It was concluded that the double-clamp technique did not reduce the incidence of myocardial infarction after elective on-pump coronary artery bypass grafting, and use of a single clamp is safe with no adverse effect on postoperative outcome.     

Off-pump versus on-pump coronary artery bypass: does number of grafts performed represent a selection bias in comparative studies? Results from a matched cohort comparison.

BACKGROUND: Several retrospective studies comparing off-pump and on-pump coronary surgery and the largest randomized studies published to date showed a lower number of grafts performed in patients submitted to off-pump coronary artery bypass surgery (OPCAB). These findings bring about the question of the general applicability of the results. We eliminated the selection bias correlated with the number of grafts per patient by comparing the short-term outcomes of patients undergoing OPCAB and standard coronary artery bypass grafting (CABG) matched for number of grafts. METHODS: Eighty-seven consecutive patients undergoing OPCAB (group A) were selected from the database of our Institution during a 2-year period. Matching was performed by iterative selection prioritizing, in the following sequence: number of grafts, EuroSCORE, and age. A total of 87 patients operated upon with the on-pump technique represented the control group (group B). RESULTS: There were no significant differences in preoperative characteristics between the two groups. The number of grafts per patient was 2.2 +/- 0.5 in group A and 2.2 +/- 0.5 in group B. Early mortality did not differ between the two groups and it was 2.2% (2 patients) in group A and 3.4% (3 patients) in group B (p = NS). The incidence of myocardial infarction did not differ between the two groups. No patient in either group had stroke or coma. Five (5.7%) patients in group A and 7 (8.0%) patients in group B had atrial fibrillation (p = NS). CONCLUSIONS: We were unable to demonstrate any significant differences in short-term mortality or morbidity outcome between OPCAB and standard CABG patients Our findings suggest that excellent results can be obtained with both surgical approaches.     

Indexed effective orifice area after mechanical aortic valve replacement does not affect left ventricular mass regression in elderly.

OBJECTIVE: After aortic valve replacement, the effects of a small functional prosthesis on the extent and pattern of regression of left ventricular hypertrophy and on clinical outcomes may be less significant in older patients with low cardiac output requirements. The objective of this study was therefore to determine whether patient-prosthesis mismatch affects left ventricular mass regression in the elderly. METHODS: The population studied was made up of 88 patients over 65 years of age with pure aortic stenosis who underwent mechanical aortic valve replacement. The effective orifice area index was calculated for each patient on the basis of the projected prosthesis in vivo effective orifice area. It was considered a continuous variable and influence of its entire range of values on the extent of left ventricular mass regression was analyzed in a multivariate prediction model. RESULTS: Even though, in the group with prosthesis-patient mismatch there was a trend for lower postoperative left ventricular mass index (115+/-24 g/m(2) vs 102+/-27 g/m(2), p=0.24) and postoperative peak trans-prosthetic gradients (32+/-9.8 mmHg vs 28.9+/-7.79 mmHg, p=0.35) these differences were not statistically significant. The prevalence of residual left ventricular hypertrophy at follow-up was 50% in the group with patient-prosthesis mismatch and 50% in the group without patient-prosthesis mismatch (p=0.83). In multivariate analysis the only factors associated with indexed left ventricular mass were the follow-up time (p=0.015, r(2)=0.22) and preoperative indexed left ventricular mass (p=0.0012, r(2)=0.11). CONCLUSIONS: The major finding of our study is that patient-prosthesis mismatch does not affect left ventricular mass regression in patients older than 65 with pure aortic stenosis who underwent mechanical aortic valve replacement. In older patients with low cardiac output requirements, even a small change in the valve effective orifice area after aortic valve replacement with modern efficient mechanical prosthesis, will result in a marked reduction of pressure gradient and this will be associated with a significant regression of left ventricular mass.