Acute and mid-term outcomes after treatment of multiple, recurrent restenoses of the lower limb arteries.

AIM: Recanalization of long segmental occlusions of femoropopliteal arteries can be achieved by angioplasty and implantation of nitinol stents with high procedural success rates. However, due to recurrent in-stent restenoses (ISR) some patients need repeated interventions and their intermediate success rates are uncertain. METHODS: Patients who were treated in our center from March 2008 through February 2011 due to symptomatic ISR (as determined by Duplex sonography) were retrospectively included in the study. After endovascular treatment of their ISR, they were prospectively evaluated with regard to recurrent ISR of the target lesions. RESULTS: A total of 36 limbs (=lesions) in 32 patients (69% male, mean age 69±9 years) were successfully treated by balloon-angioplasty. Adjunctive cutting balloons and drug eluting balloons were used in 78% and 8%, respectively. Mean follow-up was 326 days. Recurrent ISR occurred in 10 (28%) lesions, while 26 (78%) lesions showed no recurrence of ISR. In a multivariate logistic regression analysis, age, gender, cardiovascular risk factors, renal failure and medication with cilostazol were not significantly associated with recurrent ISR. Moreover, the number of previous interventions of the target lesions was not an independent predictor of recurrent ISR. CONCLUSION: Patients with multiple recurrences of ISR seem to have the same prospects of acute and mid-term success for endovascular treatment as those with first presentation of ISR. However, this observation has to be confirmed by prospective, large scale studies with a longer follow-up period to determine the significance of endovascular intervention within the scope of different revascularization approaches for treatment of recurrent ISR.

Delineation of experimental liver tumors in rabbits by a new ultrasound contrast agent and stimulated acoustic emission.

RATIONALE AND OBJECTIVES: A new ultrasound contrast agent (SH U 563 A), consisting of hollow biodegradable polymeric microparticles, and a new imaging technique (stimulated acoustic emission) were used for delineation of experimental liver tumors. After intravenous injection, these microparticles are phagocytosed by cells of the reticuloendothelial system (RES) and create a color-coded signal using color Doppler. Because of the different distribution of phagocytic cells in healthy liver tissue and tumors, the delineation of focal lesions was to be tested. METHODS: Sixteen rabbits with VX2 liver tumors received doses of 0.15-mL SH U 563 A per kilogram of body weight intravenously. Liver investigations (UM9, HD1, L10.5, ATL, Bothell, USA) were performed in vivo before and after SH U 563 A application in B and color Doppler modes. Additionally, the liver and spleen of these rabbits were examined ex vivo in color Doppler. The sonographic diagnosis was confirmed by pathology. RESULTS: After application of SH U 563 A, the healthy liver tissue of all rabbits was characterized by a typical mosaic color pattern in vivo and ex vivo, using color Doppler. Entire VX2 liver tumors were detectable exclusively in color Doppler after SH U 563 A application. This was possible in 14 of 16 rabbits in vivo and in all 16 livers ex vivo. Furthermore, all ex vivo investigated spleens were color enhanced homogeneously. Sonographic diagnoses were in accordance with pathologic findings. CONCLUSIONS: SH U 563 A, combined with stimulated acoustic emission, provides potential for delineation of small isoechogenic liver lesions by sonography.

Micro-lightguide spectrophotometry (O2C®) as a predictor of intermediate outcome in patients with critical limb ischemia after percutaneous transluminal angioplasty (PTA).

AIM: Micro-lightguide spectrophotometry (O2C®) provides easily and rapidly measurable parameters of tissue microcirculation. The aim of this study was to assess whether micro-lightguide spectrophotometer (O2C®) based parameters of the tissue microcirculation can serve as predictors of ulcer healing. Furthermore, we tried to identify cut off values to forecast patient outcome and check other diagnostic meanings of individual O2C-parameters. METHODS: Forty individuals, all suffering from critical limb ischemia and arterial or arteriovenous ulcers were retrospectively investigated concerning O2C®- and ankle/toe brachial index-measurements before and up to two times after percutaneous transluminal angioplasty (PTA). At a median follow-up of 7 (range 3 to 14) months after PTA the current peripheral arterial disease (PAD) status, ulcer healing, adverse cardiovascular events including death and endovascular or surgical treatments were noted. RESULTS: We found in patients with healing wounds a significant increase in oxygen saturation (SO2, median 26.35±26.94%) compared to non-healers (-4.27±25.24%, P=0.006) as well as regarding blood flow (median 41.12±51.23AU vs. -9.46±24.01 AU, P=0.005). Additionally, the parameter rHb separated reliably between arterial and arteriovenous ulcers (P=0.024). In Cox regression models, increases after revascularisation of more than 6 % in SO2 (HRR=6.08, 95%CI 1.56-23.65, P=0.009) and flow decreases of less than 12 AU (HRR 4.95, 95%CI 1.42-17.31, P=0.012) were significantly associated with amputation-free survival. CONCLUSION: The O2C®-parameters SO2 and flow provide prognostic information for ulcer healing as well as for amputation-free survival, and rHB adds information about a possible arterial or arteriovenous genesis of an ulcer.

[Dual-source computed tomography: effect on regional and global left ventricular function assessment compared to magnetic resonance imaging]. / Untersuchung der regionalen und globalen linksventrikulären Funktion mit der Dual-Source-Computertomografie im Vergleich zur Magnetresonanztomografie.

PURPOSE: To determine regional and global left ventricular (LV) functional parameters and to perform segmental wall thickness (SWT) and motion (WM) analysis of dual-source CT (DSCT) with optimized temporal resolution versus MRI. MATERIALS AND METHODS: 30 patients with known or suspected CAD, non-obstructive HCM, DCM, ARVCM, Fallot Tetralogy, cardiac sarcoidosis and cardiac metastasis underwent DSCT and MRI. The DSCT and MR images were evaluated: end-systolic (ESV), end-diastolic LV (EDV) volumes, stroke volume (SV), ejection fraction (EF), and myocardial mass (MM) as well as LV wall thickening and segmental WM applying the AHA model were obtained and statistically analyzed. RESULTS: The mean LV-EDV (r = 0.96) and ESV (r = 0.98) as well as LV-EF (r = 0.97), SV (r = 0.83), and MM (r = 0.95) correlated well. Bland Altman analysis revealed little systematic underestimation of LV-EF (-1.1 +/- 7.8 %), EDV (-0.3 +/- 18.2 ml), SV (-1.3 +/- 16.7 ml) and little overestimation of ESV (1.1 +/- 7.8 ml) and MM (12.8 +/- 14.4 g) determined by DSCT. Systolic reconstruction time points correlated well (DSCT 32.2 +/- 6.7 vs. MRI 35.6 +/- 4.4 % RR-interval). The LV wall thickness obtained by DSCT and MRI showed close correlation in all segments (Ø diff 0.42 +/- 1 mm). In 413 segments (89 %) WM abnormalities were equally rated, whereas DSCT tended to underestimate the degree of wall motion impairment. CONCLUSION: DSCT with optimized temporal resolution enables regional and global LV function analysis as well as segmental WM analysis in good correlation with MRI. However, the degree of WM impairment is slightly underestimated by DSCT.