Midterm results of thoracic endovascular aortic repair in patients with aneurysms involving the descending aorta originating from chronic type B dissections.

BACKGROUND: Midterm results of TEVAR (thoracic endovascular aortic repair) in patients with aneurysms involving the descending aorta originating from chronic type B dissections are not known. METHODS: Between 2004 and 2009, 14 patients with a median age of 63 years (79% male) with this pathology were treated. Seven patients underwent supraaortic transpositions in various extents prior to TEVAR in order to gain a sufficient proximal landing zone. RESULTS: Median time from dissection to treatment was 19 months (4 to 84 months). All patients had an uneventful in-hospital course. The median covered length of the aortic arch and descending aorta was 190 mm (100 to 250 mm). Primary success rate defined as absence of type Ia endoleakage was 86%. No patient, where visceral or renal vessels originated from the false or from both lumina sustained ischemic injury by TEVAR. The median follow-up period is 34 months to date (6 to 64 months). Aortic-related morbidity and mortality during follow-up was low (14%). CONCLUSIONS: Midterm results of TEVAR in patients with aneurysms involving the descending aorta originating from chronic type B dissections are good. The self-expanding capability of the stent grafts is sufficient over time. However, extensive coverage of the descending aorta is warranted to achieve success. Further studies are needed to extend our knowledge in this particular subgroup of patients.

Endovascular and conventional treatment of thoracic aortic aneurysms: a comparison of costs.

BACKGROUND: The purpose of this study is to compare costs of conventional surgical therapy with costs of endovascular stent-graft placement in patients with thoracic aortic aneurysms. METHODS: Fifteen patients undergoing either conventional surgical therapy or endovascular stent-graft placement of thoracic aortic aneurysms were analyzed. A catalog of costs was then created for both procedures and this catalog was applied individually to each patient. RESULTS: Total costs of the service provision of endovascular stent-graft placement including anesthesia were 38.220.98 euros considering 1.7 stent-grafts per patient and including 5900.00 euros (Euros) for days of care. In conventional surgical therapy, adding the costs of the service provision of left heart catheterization, conventional surgical therapy including anesthesia, as well as intraoperative echocardiography a sum of 19.534.12 euros was calculated. Days of care accounted for 31.230.00 euros and total costs of 50.764.12 euros were calculated. The difference between total costs of the two procedures was 12.543.14 euros. CONCLUSIONS: Costs of endovascular stent-graft placement in patients with thoracic aortic aneurysms compare favorably with conventional surgical therapy, revealing a cost benefit of 24.7%. Higher procedural costs are outweighed by a lower number of days of care. Nevertheless, aneurysm-related secondary endovascular or surgical procedures may balance the benefit of endovascular therapy. Which strategy to choose, conventional or endovascular, should remain to be based on age, comorbidity, and technical feasibility.

Mechanical aortic valve prostheses in the small aortic root: Top Hat versus standard CarboMedics aortic valve.

BACKGROUND: The purpose of this study was to evaluate outcome in patients with a small aortic root receiving either a standard CarboMedics mechanical aortic valve or a Top Hat CarboMedics valve (CarboMedics, Austin, TX), specifically designed for the small aortic root. METHODS: Between 1986 and 2006, 316 consecutive patients underwent 19- or 21-mm mechanical aortic valve replacement, receiving either a CarboMedics Top Hat bileaflet valve (n = 56; mean age, 66 +/- 14 years) or a standard CarboMedics aortic valve replacement (n = 260; mean age, 60 +/- 13 years) at our institution based on institutional indications for the choice of type of valve prostheses. Median follow-up time was 83.5 months. We studied survival, valve-related and non-valve-related events, and hemodynamic performance by serial echocardiographic follow-up studies. RESULTS: In-hospital mortality was 8.9% in the Top Hat group and 10.0% in the standard group (p = 0.354). Five- and ten-year survival in patients in the Top Hat group was 83% and 67%, respectively. Five- and ten-year survival in the standard group was 73% and 59%, respectively (log-rank = 0.331). There were no differences in regard to valve-related and non-valve-related events. Cox regression analysis revealed age (hazard ratio, 1.045; 95% confidence interval, 1.026 to 1.066), previous cardiac surgery (hazard ratio, 1.812; 95% confidence interval, 1.101 to 2.982), additional procedures at the time of valve replacement (hazard ratio, 2.604; 95% confidence interval, 1.651 to 4.108), New York Heart Association class IV (hazard ratio, 3.645; 95% confidence interval, 1.214 to 10.945), and severely impaired left ventricular ejection fraction (hazard ratio, 2.253; 95% confidence interval, 1.289 to 3.941) to be independent predictors of survival. CONCLUSIONS: Mechanical aortic valve replacement in the small aortic root is associated with substantial perioperative mortality, in particular in the subset of patients requiring additional cardiac surgical procedures. Nevertheless, long-term outcome is satisfying. Because the type of prosthesis does not predict outcome in the multivariate Cox model, we conclude that use of the smaller Top Hat prosthesis can be recommended for the challenging cohort of patients with a small aortic root.

Detection of high-grade stenoses with multislice computed tomography in heart transplant patients.

BACKGROUND: Post-transplant follow-up of heart transplant patients consists of repeated coronary angiography, which is associated with high costs, discomfort and risk. We sought to determine whether multislice computed tomography (MSCT) permits the exclusion or progression of coronary artery disease in heart transplant patients. METHODS: MSCT scanning (Philips CT MX 8000 IDT) and invasive coronary angiography were performed on 66 consecutive heart transplant patients. One hundred milliliters of non-ionic iodinated contrast medium was applied for CT angiography. For MSCT analysis, coronary arteries and side branches with a diameter > or =1.5 mm were assessed for the presence of luminal narrowing of >70%. MSCT results were compared with those of quantitative coronary angiography analysis. RESULTS: Ten patients (17%) had one significant stenosis, whereas 3 patients (5%) had 2-vessel disease and none had 3-vessel disease. MSCT was performed successfully on 60 patients enrolled in our analysis. Forty-two of 44 patients (95%) who were estimated to be fully evaluable for MSCT were correctly classified. On per-segment-based analysis, sensitivity, specificity and positive and negative predictive values were 59%, 94%, 91% and 99.43%, respectively. After exclusion of unevaluable segments, sensitivity and specificity increased to 71% and 99.86%, respectively. On per-patient-based analysis, sensitivity, specificity and positive and negative predictive values were 88%, 97%, 88% and 97%, respectively, in evaluable transplant recipients. CONCLUSIONS: MSCT with its high specificity and high negative predictive value allows the exclusion of significant coronary artery vasculopathy in evaluable patients. From the clinical point of view, this might spare additional invasive coronary angiography in heart transplant patients.

Activation of the purine salvage pathway in mononuclear cells of cardiac recipients treated with mycophenolate mofetil.

BACKGROUND: The objective of this study was to investigate purine nucleotide metabolism in peripheral blood mononuclear cells (PBMC) of cardiac transplant recipients switched from azathioprine to mycophenolate mofetil (MMF). METHODS: Concentrations of guanosine 5'triphosphate (GTP) and adenosine 5'triphosphate (ATP), the activities of inosine monophosphate dehydrogenase (IMPDH), guanine phosphoribosyltransferase (GPRT), and hypoxanthine phosphoribosyltransferase (HPRT) were determined in PBMC of 27 cardiac transplant recipients before switch to MMF and 3, 6, and 12 months thereafter. RESULTS: There was no difference in the activities of IMPDH and salvage pathway enzymes GPRT and HRPT as well as in intracellular GTP and ATP concentrations between the patients before switch to MMF and healthy controls. The GTP and ATP concentrations in PBMC of cardiac recipients did not change during the entire observation period. Although the MPA trough level remained similar, IMPDH activity declined from 897 to 316 pmol/10(6)PBMC/h 3 months after MMF onset, was almost completely inhibited after 6 months, and partially restored to 143 pmol/10(6)PBMC/h 12 months after switch to MMF. In contrast, GPRT activity increased after 3, 6, and 12 months of MMF therapy and HPRT activity 3 and 6 months after switch to MMF. CONCLUSIONS: We demonstrated for the first time an induction of salvage pathway enzyme activities in PBMC under MMF therapy. This probably accounts for the maintenance of intracellular purine nucleotide pools and prevents the GTP depletion.

Transplant coronary artery disease: Incidence, progression and interventional revascularization.

BACKGROUND: Allograft coronary artery disease (CAD) remains the main factor responsible for late graft loss. This analysis describes data on incidence and progression of allograft CAD at our institute, as well as our experience with coronary interventions in heart transplant recipients. METHODS: Angiographic results of cardiac transplant patients undergoing coronary angiography were prospectively selected and analyzed. Angiographic outcome at follow-up were assessed for all coronary revascularizations in denovo lesions. RESULTS: Four hundred thirty-two coronary angiographies were performed in a total of 246 patients. Seventy-six patients (30.9%) showed angiographic evidence of CAD with %DS>50%, of which 48 patients revealed significant stenosis with %DS>70% (19.5%). Within the first 5 years after the transplantation, 10.1% show angiographic signs of a CAD; at the time of 10.1 years, 50% of all heart transplant patients have developed a CAD. Once a CAD with %DS between 50% and 60% has evolved, the disease shows fast progression. Coronary intervention was performed in 28 vessels at an average time of 9.5 years after heart transplantation. Follow-up angiography was available for 27 vessels (1 death before re-angiography) within a mean follow-up period of 19.3 months. Binary restenosis was found in 7 out of 27 vessels (25.9%). Comparison of the occurrence of total occlusion in vessels with %DS>70% which were not revascularized to the occurrence of MACE after successful revascularization revealed better long term results in the group of patients with coronary intervention (p=0.04). CONCLUSION: Whereas coronary artery disease is found in rare cases within the first 5 years after heart transplantation, the incidence grows in exponential manner after this period. Mid-term follow-up after coronary intervention exhibit restenosis-rates which are similar to the ones of other high risk patients. Comparison of coronary intervention versus conservative treatment in vessels with %DS>70% show significant better mid-term outcome in the interventional group.