Biomedical subjects

L Pace

Publications and source records attributed to L Pace.

116 records · Page 7Linked to original sources

PubMedDate not supplied

Quantitative thallium-201 and technetium 99m sestamibi tomography at rest in detection of myocardial viability in patients with chronic ischemic left ventricular dysfunction.

BACKGROUND: This study was designed to determine the most effective quantitative threshold for thallium-201 and technetium 99m sestamibi uptake on tomographic imaging after rest injection for the detection of myocardial viability in patients with chronic myocardial infarction. METHODS AND RESULTS: Thallium and sestamibi cardiac tomography at rest was performed in 43 patients with chronic myocardial infarction and impaired left ventricular (LV) function undergoing coronary revascularization. In all patients, echocardiography and radionuclide angiography were performed at baseline and repeated 12 months later to evaluate recovery of regional LV function and LV ejection fraction, respectively. Optimal threshold cutoff points to separate reversible from irreversible dysfunction were determined by receiver operating characteristic analysis. When all dysfunctional segments were considered, the best cutoff point in the identification of reversible LV dysfunction for both thallium and sestamibi activity was 67%. When only akinetic or dyskinetic segments were considered, the best cutoff point in the identification of reversible LV dysfunction was 58% for thallium and 55% for sestamibi. In these segments, the area under the receiving operating characteristic curves constructed for thallium and sestamibi activity were 0.74+/-0.05 and 0.75+/-0.04, respectively (P = not significant). LV ejection fraction was 33%+/-7% at baseline and increased to 37%+/-7% after revascularization (P<.0001). A significant relation between the number of akinetic or dyskinetic but viable myocardial segments and revascularization-induced changes in LV ejection fraction was observed for both thallium (r = 0.60, P<.0001) and sestamibi (r = 0.64, P<.0001) imaging. CONCLUSIONS: In patients with chronic myocardial infarction, quantitative analysis of thallium and sestamibi activity on tomographic imaging at rest predicts recovery of regional and global LV dysfunction after revascularization procedures. The most effective quantitative threshold for detecting reversible LV dysfunction is comparable for thallium and sestamibi tomographic imaging. However, the optimal cutoff point is different for both tracers when all dysfunctional segments are considered or when the analysis is focused only on segments with more severe functional impairment (i.e., akinetic or dyskinetic segments).

Chronic Disease↗

PubMedDate not supplied

Increased levels of NF-kappaB inhibitors (IkappaBalpha and IkappaBgamma) in the intestinal mucosa of Crohn's disease patients during infliximab treatment.

The treatment with infliximab is employed successfully in Crohn's disease (CD) but predictors of efficacy are lacking. Activation of the transcription factor NF-kB has been demonstrated in CD and its inhibition is one of the mechanisms by which anti-inflammatory agents exert their effects. We evaluated the production of TNFalpha by peripheral blood mononuclear cells (PBMC) and the levels of NF-kappaB family molecules in the intestinal mucosa during infliximab therapy in 12 patients. TNFalpha was assayed on supernatants of PBMC culture stimulated with PHA or LPS. Immunohistochemistry was also done on intestinal biopsies. In six patients, Western blot analysis of the NF-kappaB subunit Rel-A, and its inhibitors IkappaBalpha and IkappaBgamma was performed on intestinal biopsies and PBMC. The TNFalpha production by LPS stimulated PBMC showed mild changes, while it was increased by PHA-stimulated PBMC after treatment. The number of inflammatory cells in the intestinal mucosa was reduced (p<0.002) by the treatment. In five out of six cases we detected an increase of the IkappaBalpha and IkappaBgamma)inhibitor levels in intestinal biopsies after treatment. An increase of IkappaB inhibitors levels could be one of the mechanisms by which infliximab decreases NF-kappaB activity and exerts its anti-inflammatory effects.

Adult↗

PubMedDate not supplied

[Ambulatory monitoring of left ventricular function with a radionuclide detector system].

The recent development of new radionuclide detectors allows noninvasive outpatient monitoring of left ventricular function. This study was aimed at describing a new radionuclide technique useful to monitor cardiac function and at evaluating its potential clinical applications. We studied 14 normal subjects, 30 patients with coronary artery disease and 25 patients with dilated cardiomyopathy. Left ventricular function was continuously monitored in control conditions at rest, during daily physical activity of different intensity (walking on a level surface and climbing stairs), and during bicycle exercise. Left ventricular ejection fraction (EF) variability during recording in control conditions at rest was 0.2 +/- 1.8%. A significant relationship between outpatient EF at rest and conventional equilibrium radionuclide angiography was observed (r = 0.97, n = 69, p less than 0.001). In normal subjects both daily physical activity and exercise stress test induced an increase in heart rate and EF. In patients with coronary artery disease and in patients with dilated cardiomyopathy a heterogeneous EF response was observed during physical activity and exercise stress test. Our results demonstrate that this technique can be used for the ambulatory monitoring of left ventricular function in both normal subjects and patients with different types of cardiomyopathies.

Adult↗

PubMedDate not supplied

[Myocardial scintigraphy with technetium 99m methoxyisobutylisonitrile. A comparison with coronary arteriography in patients with suspected ischemic cardiopathy].

Technetium-99m methoxy-isobutyl-isonitrile (MIBI) myocardial scintigraphy has been proposed as an alternative to Thallium 201 myocardial imaging in the evaluation of patients with coronary artery diseases. We studied 39 patients (37 men, mean age 56 +/- 9 years) with suspected coronary artery disease. All patients underwent 99mTc MIBI myocardial scintigraphy after stress and at rest. Coronary arteriography, performed within 1 month, showed significant (greater than or equal to 50%) stenosis of at least 1 epicardial coronary artery in 36 subjects. 99mTc MIBI myocardial scintigraphy exhibited 94% sensitivity (34/36 patients) and 100% specificity (3/3 subjects with normal coronary arteries). Sensitivity for individual vessel stenosis was 81% (96% for the left anterior descending artery, 65% for the circumflex artery and 79% for the right artery). Our data show that 99mTc MIBI myocardial scintigraphy is capable of evaluating patients with coronary artery diseases.

Contrast Media↗

PubMedDate not supplied

Sedation in gynaecologic oncology day surgery.

Gynaecologic oncology day surgery deals primarily with the diagnosis of endometrial, cervical, vulvar and vaginal tumors. Conscious sedation is an important technique used in gynaecologic oncology day surgery. It is often associated with regional anaesthesia. The goals of conscious sedation are to provide effective pain control with complete safety, reduction of the recovery time, of the infection risk and cost. Since the consequences of the immunosuppressive effects of the opiates and the surgical stress could lead to an increased susceptibility to post-operative infections and a possible lack of immunological defence in the cancer patients, we investigated the possibility of eliminating the administration of opiates during minor operations in gynaecologic oncology day surgery. In this study, 400 patients, aged between 35 and 77 years, underwent surgery using sedation at the day hospital annexed to the Gynaecology and Obstetrics Department of the 2nd University of Naples, Italy. The patients were randomized into two equal study groups, according to a computer-generated randomised list. All patients were seen by the consultant anaesthetist three days before surgery. In all cases, during surgery, we monitored the main vital parameters such as ECG, HR and RR, BT, BP and SO. The drugs commonly used were: opioids, hypnotics and benzodiazepines, associated or not, with local anaesthetics. By using these drugs, pain and anxiety were reduced, sedation and amnesia were accomplished. In our experience, conscious sedation seems to be the best choice in gynaecologic oncology day surgery because it presents low toxicity, is short acting and readily reversible, has a low cost and, finally, because it is more comfortable for the patients. Moreover, it is possible to eliminate the administration of opiates during conscious sedation for less invasive surgical procedures.

Adult↗

PubMedDate not supplied

MR findings in lipoma arborescens of the knee: our experience.

PURPOSE: This paper describes the role of MR imaging in the identification of the different macroscopic patterns of lipoma arborescens. MATERIALS AND METHODS: Between June 1995 and January 2004, a total of 6387 MR examinations of the knee were retrospectively assessed for the presence of lipoma arborescens. The MR examinations were performed using a superconductive 0.5 T MR unit with a transmitting/ receiving coil dedicated for the extremities. The MR images were acquired with SE T1-weighted, GE T2-weighted and STIR sequences in sagittal, coronal and axial planes with 3-mm thickness and 1-mm gap. RESULTS: Lipoma arborescens was identified in 9 patients (mean age: 36 years). In 2/9 cases a localized lipoma arborescens was detected as a well-marginated single nodule on the suprapatellar bursa without irregularity or synovial hyperplasia. In the remaining 7 cases diffuse lipoma arborescens was identified on the wall of the suprapatellar bursa. In one case of diffuse lipoma arborescens there was involvement of both knees. In all cases the MR findings were verified at surgery and the final diagnosis was made by histological examination. CONCLUSIONS: MR imaging shows a high accuracy in the identification and characterization of lipoma arborescens, due to its multiplanar capabilities and high contrast resolution. MRI allows correct evaluation of size and grade, accurate treatment planning and effective follow-up, avoiding the need for synovial biopsy.

Journal Article↗

PubMedDate not supplied

[Evaluation of systolic parietal thickening of the left ventricle using technetium-99m methoxy isobutyl isonitrile. Relationship with coronary anatomy].

Forty-three patients (40 men and 3 women, mean age 54 +/- 9 years) with coronary artery disease underwent 99mTc methoxy isobutyl isonitrile (sestamibi) myocardial scintigraphy and coronary arteriography. Sestamibi uptake and wall thickening index (WTI) were quantitatively evaluated in each myocardial segment. Segments were divided into group 1 (normal coronary arteries, no. = 94), group 2 (coronary artery stenosis 50-99%, no. = 79), and group 3 (coronary artery stenosis 100%, no. = 42). Group 3 segments were subdivided into group 3A (with collaterals, no. = 18) and group 3B (without collaterals, no. = 24) segments. Both sestamibi uptake and WTI were significantly lower (p < 0.01) in group 3 than in groups 1 and 2. However, only WTI was significantly reduced (p < 0.01) in group 3B vs group 3A. Diagnostic capabilities (i.e. identification of segments supplied by stenosed coronary arteries) of sestamibi uptake, WTI, and a combination of both variables with a discriminant function were compared by analysis of receiver operator characteristic curve (ROC) areas. The diagnostic capabilities of sestamibi uptake (ROC area = 0.65 +/- 0.04) were significantly lower (p < 0.05) than those of WTI (ROC area = 0.81 +/- 0.03) and discriminant function (ROC area = 0.83 +/- 0.03). In conclusion, our data suggest that combined analysis of myocardial perfusion and regional ventricular function may increase the diagnostic accuracy of sestamibi myocardial scintigraphy in identifying myocardial segments supplied by stenosed coronary arteries.

Cardiomegaly↗

PubMedDate not supplied

[Effects left ventricle asynchrony on systolic and diastolic function in patients with non-ischemic heart failure].

INTRODUCTION: The asynchrony of the left ventricle--i.e., its nonuniform contraction and relaxation--is an important factor for left ventricular function. Heart failure is often related to abnormal systolic function, sometimes associated with a diastolic dysfunction. We studied the relationship of left ventricular asynchrony to left ventricular function in patients with nonischemic heart failure. MATERIAL AND METHODS: Radionuclide angiography at rest was performed in 25 patients with nonischemic heart failure and in 26 age and sex matched normal subjects. In addition to ejection fraction and peak filling rate, two indices of left ventricular asynchrony were calculated: the coefficient of variation of regional time to end systole and the coefficient of variation of regional time to peak filling rate. These factors indicate how disperse are the regional values of time to end systole and of time to peak filling rate. In fact, the higher the value, the greater the asynchrony. RESULTS: A significant (r = .46, p < .05) inverse correlation was found between the ejection fraction and the coefficient of variation of regional time to end systole in both the normal subjects and the heart failure patients, while the ejection fraction correlated significantly (r = .46, p < .05) with the coefficient of variation of regional time to peak filling rate only in the patients. Moreover, the peak filling rate was inversely correlated (r = .57, p < .05) with the coefficient of variation of regional time to peak filling rate in the heart failure patients but not in the normal subjects. CONCLUSIONS: These results suggest that left ventricular systolic and diastolic asynchrony may contribute to impair left ventricular systolic and diastolic function in patients with nonischemic heart failure.

Adult↗