70 research outputs found
Does tumescent liposuction damage the lymph vessels in lipoedema patients?
Background: Lymphatic insufficiency might play a significant role in the pathophysiology of lipoedema. Liposuction is up to now the best treatment. As liposuction is invasive, the technique could destruct parts of the lymphatic system and by this aggravate the lymphatic component and/or induce lymphoedema. We investigated the function of the lymphatic system in lipoedema patients before and after tumescent liposuction and thus whether tumescent liposuction can be regarded as a safe treatment. Methods: Lymphoscintigraphy was performed to quantify the lymph outflow of 117 lipoedema patients. Mean clearance percentages of radioactive protein loaded after 1Â min with respect to the total injected dose and corrected for decay of the radiopharmaceutical in the subcutaneous lymphatics were used as functional quantitative parameters as well as the clearance percentages and inguinal uptake 2Â h post injection. The results of lymphatic function in lipoedema patients were compared with values obtained from normal healthy volunteers. We also compared 50 lymphoscintigraphies out of the previous 117 lipoedema patients before and six months after tumescent liposuction. Results: In 117 lipoedema patients clearance 2 h post injection in the right and left foot was disturbed in 79.5 and 87.2% respectively. The inguinal uptake 2 h post injection in the right and left groin was disturbed in 60.3 and 64.7% respectively. In 50 lipoedema patients mean clearance and inguinal uptake after tumescent liposuction were slightly improved, 0.01 (p = 0.37) versus 0.02 (p = 0.02), respectively. This is statistically not relevant in clearance. Conclusion: Lipoedema legs have a delayed lymph transport. Tumescent liposuction does not diminish the lymphatic function in lipoedema patients, thus tumescent liposuction can be regarded as a safe treatment.</p
Impact of clinically tested NEP/ACE inhibitors on tumor uptake of [111In-DOTA]MG11
Background: We have recently shown that treatment of mice with the neutral endopeptidase (NEP) inhibitor phosphoramidon (PA) improves the bioavailability and tumor uptake of biodegradable radiopeptides. For the truncated gastrin radiotracer [111In-DOTA]MG11 ([(DOTA)DGlu10]gastrin(10–17)), this method led to impressively high tumor-to-kidney ratios. Translation of this concept in the clinic requires the use of certified NEP inhibitors, such as thiorphan (TO) and its orally administered prodrug racecadotril (Race). Besides NEP, angiotensin-converting enzyme (ACE) has also been implicated in the catabolism of gastrin analogs. In the present study, we first compared the effects induced by NEP inhibition (using PA, TO, or Race) and/or by ACE inhibition (using lisinopril, Lis) on the biodistribution profile of [111In-DOTA]MG11 in mice. In addition, we compared the efficacy of PA and TO at different administered doses to enhance tumor uptake. Methods: [111In-DOTA]MG11 was coinjected with (a) vehicle, (b) PA (300 μg), (c) TO (150 μg), (d) Lis (100 μg), (e) PA (300 μg) plus Lis (100 μg), or (f) 30–40 min after intraperitoneal (ip) injection of Race (3 mg) in SCID mice bearing AR42J xenografts. In addition, [111In-DOTA]MG11 was coinjected with vehicle, or with progressively increasing amounts of PA (3, 30, or 300 μg) or TO (1.5, 15, and 150 μg) in SCID mice bearing twin A431-CCK2R(+/−) tumors. In all above cases, biodistribution was conducted at 4 h postinjection (pi). Results: During NEP inhibition, the uptake of [111In-DOTA]MG11 in the AR42J tumors impressively increased from 1.8 ± 1.0 % ID/g (controls) to 15.3 ± 4.7 % ID/g (PA) and 12.3 ± 3.6 % ID/g (TO), while with Race tumor values reached 6.8 ± 2.8 % ID/g. Conversely, Lis had no effect on tumor uptake and no additive effect when coinjected with PA. During the dose dependence study in mice, PA turned out to be more efficacious in enhancing tumor uptake of [111In-DOTA]MG11 in the CCK2R-positive tumors compared to equimolar amounts of TO. In all cases, renal accumulation remained low, resulting in notable increases of tumor-to-kidney ratios. Conclusions: This study has confirmed NEP as the predominant degrading enzyme of [111In-DOTA]MG11 and ruled out the involvement of ACE in the in vivo catabolism of the radiotracer. NEP inhibition with the clinically tested NEP
Peptide receptor radionuclide therapy
Peptide receptor radionuclide therapy is a new treatment modality for patients with inoperable or metastasised neuroendocrine gastroenteropancreatic tumours. After the successful implementation of somatostatin receptor scintigraphy in daily clinical practice, the next logical step was to increase the radiation dose of the administered radiolabelled somatostatin analogue in an attempt to induce tumour shrinkage. Since then, an increasing number of patients has been successfully treated with this approach, resulting in a substantial numbers of patient with objective tumour shrinkage. Serious side-effects have been rare. This article reviews the effectiveness of the different radiolabelled somatostatin analogues used, the currently known side-effects and the survival data available. Furthermore, clinical issues, including indication and timing of therapy, are discussed. Finally, important directions for future research are briefly mentioned to illustrate that, although the currently available results already suggest a favourable outcome compared with other systemic therapies, new strategies are being developed to increase efficacy
Safety, hemodynamic profile, and feasibility of dobutamine stress technetium myocardial perfusion single-photon emission CT imaging for evaluation of coronary artery disease in the elderly
OBJECTIVES: Cardiovascular disease is the leading cause of morbidity and
mortality in the elderly. The evaluation of coronary artery disease by
exercise stress testing is frequently limited by the patient's inability
to exercise. Although pharmacologic stress testing with dobutamine is an
alternative, the safety of dobutamine myocardial perfusion scintigraphy in
the elderly has not been previously studied. PATIENTS AND METHODS: We
studied the safety and feasibility of dobutamine (up to 40
microg/kg/min)-atropine (up to 1 mg) stress myocardial perfusion
scintigraphy using technetium single-photon emission CT imaging in 227
patients > or = 70 years old (mean +/- SD age, 75 +/- 4 years). A control
group of 227 patients < 70 years old (mean age, 55 +/- 11 years; matched
for gender, prevalence of previous infarction, beta-blocker therapy, and
severity of resting perfusion abnormalities) was studied to assess
age-related differences in the safety and the hemodynamic response. A
feasible test was defined as the achievement of the target heart rate
and/or an ischemic end point (angina, ST-segment depression, or reversible
perfusion abnormalities). RESULTS: No myocardial infarction or death
occurred during the test. The target heart rate was achieved more
frequently in the elderly patients (87% vs 79%; p < 0.05). The elderly
patients had a higher prevalence of supraventricular tachycardia (7% vs
1%; p < 0.005) and premature ventricular contraction (74% vs 32%; p <
0.005) during the test, as compared to the younger patients. There was a
trend to a higher prevalence of ventricular tachycardia (5% vs 2%) and
atrial fibrillation (3% vs 0.4%) in the elderly patients. Arrhythmias were
terminated spontaneously by termination of dobutamine infusion or by
administration of metoprolol. Independent predictors of supraventricular
tachyarrhythmias and ventricular tachycardia were older age (p < 0.001;
chi(2), 9.8) and myocardial perfusion defect score at rest (p < 0.01;
chi(2), 6.8) respectively, by using a multivariate analysis of clinical
and stress test variables. Elderly patients had a higher prevalence of
systolic BP drop > 20 mm Hg during the test (37% vs 12%; p < 0.05). The
test was terminated due to hypotension in 2% of the elderly patients and
in 1% of the control group. Age was the most powerful predictor of
hypotension (p < 0.005; chi(2), 10.3). The test was considered feasible in
216 elderly patients (95%) and in 209 patients of the control group (92%).
CONCLUSION: Dobutamine-atropine stress myocardial perfusion scintigraphy
is a highly feasible method for the evaluation of coronary artery disease
in the elderly. Elderly patients have a higher risk for developing
hypotension and supraventricular tachyarrhythmias during a dobutamine
stress test. However, dobutamine-induced hypotension is often asymptomatic
and rarely necessitates the termination of the test
Long-term prognostic value of dobutamine stress 99mTc-sestamibi SPECT: single-center experience with 8-year follow-up
PURPOSE: To determine the long-term prognostic value of dobutamine stress
technetium 99m (99mTc)-labeled sestamibi single photon emission computed
tomography (SPECT) in patients with limited exercise capacity. MATERIALS
AND METHODS: Clinical data and SPECT results were analyzed in 531
consecutive patients. Follow-up was successful in 528 (99.4%) patients; 55
underwent early revascularization and were excluded. Normal or abnormal
findings were considered in the absence or presence of fixed and/or
reversible perfusion defects. A summed stress score was calculated to
estimate the extent and severity of perfusion defects. Univariate and
multivariate Cox proportional hazards regression models were used to
identify independent predictors of late cardiac events. The incremental
value of myocardial perfusion scintigraphy over clinical variables in
predicting events was determined according to two models. The probability
of survival was calculated by using the Kaplan-Meier method. RESULTS:
Findings were abnormal in 312 patients. During 8.0 years +/- 1.5 of
follow-up (range, 4.5-10.6 years), cardiac death occurred in 67 patients
(total deaths, 165); nonfatal myocardial infarction, in 34; and late
revascularization, in 49. The annual rates for cardiac death, cardiac
death or infarction, and all events were 0.9%, 1.2%, and 1.5%,
respectively, after normal findings and 2.7%, 3.4%, and 4.4%,
respectively, after abnormal findings (P <.05). In a multivariable Cox
proportional hazards model, not only an abnormal finding but also the
summed stress score provided incremental prognostic information in
addition to clinical data. The hazard ratio for cardiac death was 1.09
(95% CI: 1.01, 1.18) per 1-unit increment of the summed stress score.
CONCLUSION: The incremental prognostic value of dobutamine stress
99mTc-sestamibi SPECT over clinical data was maintained over an 8-year
follow-up in patients with limited exercise capacity
Ischemia burden on stress SPECT MPI predicts long-term outcomes after revascularization in stable coronary artery disease
Background: It is not entirely clear whether ischemia burden on stress single-photon emission computed tomography (SPECT) effectively identifies patients who have a long-term benefit from coronary revascularization. Methods: The study population consisted of 719 patients with ischemia on stress SPECT. Early coronary revascularization was defined as percutaneous coronary intervention or coronary artery bypass grafting ≤90 days after SPECT. Patients who underwent late revascularization (>90 days after SPECT) were excluded (n = 164). Results: Of the 538 patients (73% men, mean age 59.8 ± 11 years), 348 patients had low ischemia burden (<3 ischemic segments) and 190 patients had moderate to high ischemia burden (≥3 ischemic segments). A total of 76 patients underwent early revascularization. During a median follow-up of 12 years (range 4-17), 283 patients died of whom 125 due to cardiac causes. Early revascularization was beneficial on all-cause mortality (HR 0.46, 95% CI 0.30-0.46) and cardiac mortality (HR 0.54, 95% CI 0.29-0.99). Conclusions: Patients with myocardial ischemia on stress SPECT who underwent early revascularization had a lower all-cause mortality and cardiac mortality during long-term follow-up as compared to patients who received pharmacological therapy alone. This difference in long-term outcomes was mainly influenced by the survival benefit of early revascularization in the patients with moderate to high ischemia burden
Prevalence of myocardial viability assessed by single photon emission computed tomography in patients with chronic ischaemic left ventricular dysfunction
OBJECTIVE: To assess the prevalence of myocardial viability by
technetium-99m (Tc-99m)-tetrofosmin/fluorine-18-fluorodeoxyglucose (FDG)
single photon emission computed tomography (SPECT) in patients with
ischaemic cardiomyopathy. DESIGN: A retrospective observational study.
SETTING: Thoraxcenter Rotterdam (a tertiary referral centre). PATIENTS:
104 patients with chronic coronary artery disease and severely depressed
left ventricular function presenting with heart failure symptoms. MAIN
OUTCOME MEASURES: Prevalence of myocardial viability as evaluated by
Tc-99m-tetrofosmin/FDG SPECT imaging. Two strategies for assessing
viability in dysfunctional myocardium were used: perfusion imaging alone,
and the combination of perfusion and metabolic imaging. RESULTS: On
perfusion imaging alone, 56 patients (54%) had a significant amount of
viable myocardium, whereas 48 patients (46%) did not. Among the 48
patients with no significant viability by perfusion imaging alone, seven
additional patients (15%) had significantly viable myocardium on combined
perfusion and metabolic imaging. Thus with a combination of perfusion and
metabolic imaging, 63 patients (61%) had viable myocardium and 41 (39%)
did not. CONCLUSIONS: On the basis of the presence of viable dysfunctional
myocardium, 61% of patients with chronic coronary artery disease and
depressed left ventricular ejection fraction presenting with heart failure
symptoms may be considered for coronary revascularisation. The combination
of perfusion and metabolic imaging identified more patients with
significant viability than myocardial perfusion imaging alone
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