It has been shown that exercise-induced coronary vasodilation of angiographically normal coronary vessels is reduced in hypercholesterolemic patients. The purpose of this study was to evaluate the ...effect of calcium channel blockers on coronary vasomotion of angiographically smooth coronary arteries in hypercholesterolemic patients.
A total of 57 patients were included in the present analysis. Vasomotion of angiographically normal coronary arteries was evaluated in 37 control subjects (group 1) without and 20 patients (group 2) with calcium blocker administration before physical exercise. Both groups were subdivided into subgroup A (normal cholesterol values: < or = 5.5 mmol/L or 212 mg%) and subgroup B (elevated cholesterol values: >5.5 mmol/L or 212 mg%). Coronary luminal area at rest and during exercise was assessed by biplane quantitative coronary angiography. The normal vessels showed a significant increase in coronary luminal area during exercise in subgroup A (n=13) with normal cholesterol values (31%; P<.05) but not in subgroup B (n=24; 13%; P=NS). In contrast, all patients in group 2 showed similar vasodilation during exercise, namely, 22% (P<.05) in subgroups A (n=8) and B (n=12) (P<.05). Independent of the actual cholesterol level, the stenotic lesions showed coronary vasoconstriction during exercise in group 1 but vasodilation in group 2 after pretreatment with calcium antagonists.
Coronary vasomotor response to exercise is inversely related to actual serum cholesterol level in angiographically normal vessels. Administration of calcium antagonists normalizes exercise-induced vasodilation and thus eliminates cholesterol-induced abnormal vasomotion, probably by a direct effect on the smooth muscles of the vasculature.
OBJECTIVE—Current imaging modalities of atherosclerosis mainly visualize plaque morphology. Valuable insight into plaque biology was achieved by visualizing enhanced metabolism in plaque-derived ...macrophages using F-fluorodeoxyglucose (F-FDG). Similarly, enhanced uptake of F-fluorocholine (F-FCH) was associated with macrophages surrounding an abscess. As macrophages are important determinants of plaque vulnerability, we tested F-FCH for plaque imaging.
METHODS AND RESULTS—We injected F-FCH (n=5) or F-FDG (n=5) intravenously into atherosclerotic apolipoprotein E-deficient mice. En face measurements of aortae isolated 20 minutes after F-FCH injections demonstrated an excellent correlation between fat stainings and autoradiographies (r=0.842, P<0.0001), achieving a sensitivity of 84% to detect plaques by F-FCH. In contrast, radiotracer uptake 20 minutes after F-FDG injections correlated less with en face fat stainings (r=0.261, P<0.05), reaching a sensitivity of 64%. Histological analyses of cross-sections 20 minutes after coinjections of F-FCH and C-FDG (n=3) showed that F-FCH uptake correlated better with fat staining (r=0.740, P<0.0001) and macrophage-positive areas (r=0.740, P<0.0001) than C-FDG (fatr=0.236, P=0.29 and CD68 stainingr=0.352, P=0.11), respectively.
CONCLUSIONS—F-FCH identifies murine plaques better than F-FDG using ex vivo imaging. Enhanced F-FCH uptake into macrophages may render this tracer a promising candidate for imaging plaques in patients.
Determination of any volumetric blood flow requires assessment of mean blood flow velocity and vessel cross-sectional area. For evaluation of coronary blood flow and flow reserve, however, assessment ...of average peak velocity alone is widely used, but changes in velocity profile and vessel area are not taken into account. We studied the feasibility of a new method for calculation of volumetric blood flow by Doppler power using a Doppler flow wire. An
in vitro model with serially connected silicone tubes of known lumen diameters (1.5, 2.0, 2.5, 3.0, 3.5 and 4.0 mm) and pulsatile blood flow ranging from 10 to 200 mL/min was used. A Doppler flow wire was connected to a commercially available Doppler system (FloMap®, Cardiometrics) for online calculation of the zeroth (
M
0) and the first (
M
1) Doppler moment, as well as mean flow velocity (
V
m). Two different groups of sample volumes (at different gate depths) were used: 1. two proximal sample volumes lying completely within the vessel were required to evaluate the effect of scattering and attenuation on Doppler power, and 2. distal sample volumes intersecting completely the vessel lumen to assess the vessel cross-sectional area. Area (using
M
0) and
V
m (using
M
1/
M
0) obtained from the distal gates were corrected for scattering and attenuation by the data obtained from the proximal gates, allowing calculation of absolute volumetric flow. These results were compared to the respective time collected flow. Correlation between time collected and Doppler-derived flow measurements was 0.98 (
p < 0.0001), with a regression line close to the line of equality indicating an excellent agreement of the two measurements in each individual tube. The mean paired flow difference between the two techniques was 1.5 ± 9.0 mL/min (ns). Direct volumetric blood flow measurement from received Doppler power using a Doppler flow wire system is feasible. This technique may potentially be of great clinical value because it allows an accurate assessment of coronary flow and flow reserve with a commercially available flow wire system.
Accurate staging is of major importance to determine the optimal treatment modality for patients with prostate cancer. Positron emission tomography (PET) with prostate-specific membrane antigen ...(PSMA) is a promising technique that outperformed conventional imaging in the detection of nodal and distant metastases in previous studies. However, it is still unclear whether the superior sensitivity and specificity also translate into improved patient management. The aim of this study was to assess the performance of
Ga-PSMA-11 PET for staging of intermediate and high-risk prostate cancer and its potential impact on disease management.
In this retrospective analysis, 116 patients who underwent
Ga-PSMA-11 PET/CT or MRI scans for staging of their intermediate or high-risk prostate cancer between April 2016 and May 2018 were included. The potential impact of
Ga-PSMA-11 PET staging on patient management was assessed within a simulated multidisciplinary tumour board where hypothetical treatment decisions based on clinical information and conventional imaging alone was determined. This treatment decision was compared with the treatment recommendation based on clinical information and
Ga-PSMA-11 PET imaging.
The primary tumour was positive on
Ga-PSMA-11 PET in 113 patients (97%). Nodal metastases were detected in 28 patients (24%) and bone metastases in 14 patients (12%). Compared with clinical staging and conventional imaging,
Ga-PSMA-11 PET resulted in new information in 42 of 116 patients (36%). In 32 of 116 patients (27%), this information would most likely have changed the management into a different therapy modality (15 patients, 13%) or adjusted treatment details (e.g. modification of radiotherapy field or lymph node dissection template; 17 patients, 14%).
Information from
Ga-PSMA-11 PET staging has the potential to change the management in more than a fourth of the patients who underwent PET staging for their intermediate to high-risk prostate cancer. Whether these more personalized
Ga-PSMA-11 PET-based treatment decisions will improve patient outcome needs further investigation.
Full text
Available for:
DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, VSZLJ, ZAGLJ
499.
Replik Kranzbühler, Benedikt; Burger, Irene A.; Schmid, Daniel M. ...
Forum médical suisse (En ligne),
01/2017, Volume:
17, Issue:
5
Journal Article