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D Lama

Publications and source records attributed to D Lama.

17 recordsLinked to original sources
PubMed2004

Freehand three-dimensional echocardiographic evaluation of the effect of telmisartan compared with hydrochlorothiazide on left ventricular mass in hypertensive patients with mild-to-moderate hypertension: a multicentre study.

Antihypertensive efficacy, effects on left ventricular mass index (LVMI) and tolerability of telmisartan, an angiotensin II receptor blocker, were compared with those of hydrochlorothiazide (HCTZ). Adult patients with mild-to-moderate hypertension and an optimal acoustic window by two-dimensional echocardiography were randomised at baseline to 12 months' double-blind, once-daily treatment with telmisartan 80 mg or HCTZ 25 mg. Two-dimensional echocardiography and freehand precordial three-dimensional echocardiography and 24-h ambulatory blood pressure monitoring were performed at baseline and after treatment. Of the 41 telmisartan group patients and 28 HCTZ group patients, 40 and 25, respectively, completed the study. Following treatment, 24-h mean SBP (telmisartan 157 +/- 11 vs 133 +/- 7 mmHg, P<0.001; HCTZ 154 +/- 10 vs 144 +/- 11 mmHg, P<0.003) and DBP (telmisartan 96 +/- 6 vs 83 +/- 5 mmHg, P<0.001; HCTZ 95 +/- 7 vs 87 +/- 8 mmHg, P<0.003) were significantly reduced. Telmisartan produced significantly greater 24-h mean SBP and DBP reductions than HCTZ (P<0.001). LVMI was significantly reduced by telmisartan (141 +/- 16 vs 125 +/- 19 g/m2, P<0.001), but not by HCTZ (139 +/- 20 vs 135 +/- 22 g/m(2)). Incidences of adverse events in both the treatment groups were low; two cases of hypokalaemia occurred with HCTZ. In conclusion, telmisartan 80 mg was well tolerated and significantly reduced SBP, DBP and LVMI after 12 months' treatment compared with HCTZ.

Adult↗
PubMed2001

Prospective randomized controlled trial of extended-release oxybutynin chloride and tolterodine tartrate in the treatment of overactive bladder: results of the OBJECT Study.

OBJECTIVE: To compare the efficacy and tolerability of extended-release oxybutynin chloride and tolterodine tartrate at 12 weeks in participants with overactive bladder. SUBJECTS AND METHODS: The OBJECT (Overactive Bladder: Judging Effective Control and Treatment) study was a prospective, randomized, double-blind, parallel-group study conducted between March and October 2000 at 37 US study sites. Participants who had between 7 and 50 episodes of urge incontinence per week and 10 or more voids in 24 hours received extended-release oxybutynin, 10 mg/d, or tolterodine, 2 mg twice daily. The outcome measures were the number of episodes of urge incontinence, total incontinence, and micturition frequency at 12 weeks adjusted for baseline. RESULTS: A total of 315 women and 63 men were randomized and treated, and 332 participants (276 women, 56 men) completed the study. At the end of the study, extended-release oxybutynin was significantly more effective than tolterodine in each of the main outcome measures: weekly urge incontinence (P=.03), total incontinence (P=.02), and micturition frequency episodes (P=.02) adjusted for baseline. Both drugs improved symptoms of overactive bladder significantly from baseline to the end of the study as assessed by the 3 main outcome measures (P<.001). Dry mouth, the most common adverse event, was reported by 28.1% and 33.2% of participants taking extended-release oxybutynin and tolterodine, respectively (P=.32). Rates of central nervous system and other adverse events were low and similar in both groups. CONCLUSIONS: Extended-release oxybutynin was more effective than tolterodine as measured by end-of-study urge incontinence, total incontinence, and micturition frequency episodes. Both groups had similar rates of dry mouth and other adverse events.

Aged↗
PubMed1999

Prognostic importance of insulin-mediated glucose uptake in aged patients with congestive heart failure secondary to mitral and/or aortic valve disease.

Previous studies have demonstrated that insulin resistance is a common feature of congestive heart failure (CHF), but the clinical significance of such insulin resistance is still debated. We tested the hypothesis that insulin-mediated glucose uptake (IMGU) is a prognostic factor in CHF in aged patients. For this purpose 174 aged patients with CHF participated in a cross-sectional and a longitudinal study of 24 months' duration. In this latter study survival analysis was calculated comparing subjects at the first and second tertile of IMGU with those at third tertile. All subjects underwent anthropometric (body mass index, waist/hip ratio), cardiovascular (arterial blood pressure, 24-hour Holter monitoring, peak VO2, left ventricular ejection fraction, echocardiography), and metabolic (determination of fasting plasma glucose, insulin, catecholamine, free fatty acids, tumor necrosis factor-alpha concentrations, and assessment of IMGU by euglycemic hyperinsulinemic glucose clamp) investigations. In the cross-sectional study, IMGU correlated with age (r = -0.33, p <0.001), body mass index (r = -0.46 p <0.001), ventricular premature complexes (r = -0.78, p <0.001), left ventricular ejection fraction (r = -0.15, p <0.05), fasting plasma norepinephrine (r = -0.75, p <0.001), tumor necrosis factor-alpha (r = -0.45, p <0.001), free fatty acids (r = -0.54, p <0.001), and peak VO2 (r = 0.67, p <0.001). In the longitudinal study patients at the first and second tertile of IMGU had a lower probability of survival than patients at the third tertile (p <0.03). Cox regression analysis showed IMGU to be a prognostic factor independent of fasting plasma norepinephrine, tumor necrosis factor-alpha, free fatty acid concentration, New York Heart Association class, peak VO2, and left ventricle ejection fraction (relative risk 1.1, 95% confidence intervals 1.0 to 2.1). In conclusion, our study demonstrates that insulin resistance is a common feature of CHF most likely due to elevated plasma norepinephrine and tumor necrosis factor-alpha concentrations, and that IMGU is an independent prognostic factor in CHF.

Aged↗
PubMed1995

Morpho-functional assessment of interatrial septum: a transesophageal echocardiographic study.

BACKGROUND: Despite the increasing number of reports on lipomatous hypertrophy of interatrial septum, a standardization of measurement of the dimensions of the interatrial septum (IAS) in the different phases of cardiac cycle has not been reported. Moreover, no data on modification of thickness with age and in specific cardiac diseases are available. OBJECTIVE: Our purpose was to study whether the changes of thickness and thinning of IAS may be related to age, left atrial dimension, cardiac cycle and different cardiac diseases. METHODS: 248 patients (mean age 52.7 +/- 19.9 years) underwent transthoracic (TTE) and transesophageal (TEE) echocardiography. IAS was measured at the constant regions anterior and posterior to the fossa ovalis. IAS thickness (tk), thinning (th) and % thinning (% th) were measured. RESULTS: IAS thickness ranged from 4 to 13 mm at the time of ventricular end-systolic phase (mean 6.7 +/- 1.9 mm) and from 6 to 16 mm at the time of atrial systole (mean 9.9 +/- 1.8 mm); significant statistical difference between these values was found (P < 0.01). IAS thinning ranged from 1 to 7 mm (mean 3.42 +/- 1.8) while % IAS thinning from 18 to 76% (mean 36.53 +/- 16.36%). Statistical analysis showed a significant positive correlation between age and ventricular end-systolic thickness and atrial systolic thickness and thinning. An insignificant correlation was found between age and % IAS thinning and between left atrial dimension and IAS tk and th. CONCLUSIONS: Our results demonstrate that IAS thickness increases by age; no correlation exists between IAS thinning and age. There is no difference between IAS thickness and thinning in patients with or without cardiac disease. We believe that the thickness of IAS can be considered hypertrophic only if it exceeds the value of 15 mm during both ventricular end-systolic and atrial systolic phases of the cardiac cycle. IAS thickness and thinning might be an additional parameter to evaluate systolic atrial function particularly with regard to maintenance of synus rhythm after conversion from atrial fibrillation as well as to better understand its role in determining the filling of ventricles in different clinical conditions.

Adolescent↗
PubMed1995

Low fasting and insulin-mediated intracellular magnesium accumulation in hypertensive patients with left ventricular hypertrophy: role of insulin resistance.

Twenty-five hypertensive patients (13 males/12 females) with left ventricular hypertrophy (LVH) and 12 hypertensive patients (6 males/6 females) without LVH were studied. Both groups were matched for age, sex, body mass index, percentage body fat, arterial BP and known duration of hypertension. After a seven day wash-out period from antihypertensive treatment each subject underwent: (1) an oral glucose tolerance test, (2) an euglycemic hyperinsulinaemic glucose clamp (insulin infusion rate 7.1 pM/kg per min), (3) an echocardiographic determination of left ventricular mass index, and (4) 24h ECG Holter monitoring. All tests were performed in random order and on different days. All investigators were unaware of the patient groups. Hypertensive patients with LVH had lower fasting intracellular (erythrocyte) magnesium concentrations (1.85 +/- 0.06 vs. 2.07 +/- 0.04 mM; P < 0.001) but higher fasting plasma insulin concentrations (86 +/- 4 vs. 59 +/- 5 pM; P < 0.001) Glucose clamp study demonstrated a lower insulin-mediated glucose disposal (24.8 +/- 0.4 vs. 30.1 +/- 0.3 microM/kg of lean body mass per min; P < 0.05) and a net change in intracellular magnesium accumulation (17.9 +/- 1.3 vs. 27.3 +/- 1.8%, P < 0.01) in response to insulin infusion in hypertensive patients with LVH than in those without LVH. After adjustment for fasting plasma insulin levels and insulin-mediated glucose uptake, fasting and insulin-mediated erythrocyte magnesium accumulation were no longer different between the two groups. In conclusion, hypertensive patients with LVH compared with those without LVH have a lower intracellular magnesium content due a higher degree of insulin resistance.

Double-Blind Method↗
PubMed1992

Impaired left ventricular relaxation and hyperinsulinemia in patients with primary hypercholesterolemia.

Fifteen non-obese patients with familial hypercholesterolemia and fifteen normocholesterolemic subjects matched for age, body mass index, waist/hip ratio, arterial blood pressure and sedentary life style underwent blood sampling for determination of fasting plasma glucose, insulin, total-, LDL-, HDL-cholesterol, triglycerides, free fatty acids, apolipoprotein A1 and B. In both groups of subjects we determined erythrocyte membrane microviscosity and performed an echocardiographic study. We demonstrated that hypercholesterolemic patients had a significant increase in fasting plasma total cholesterol (8.9 +/- 0.5 vs. 5.5 +/- 0.3 mmol/l, P less than 0.001), insulin (79 +/- 4 vs. 58 +/- 4 pmol/l, P less than 0.05) and apolipoprotein B (2.2 +/- 0.5 vs. 1.3 +/- 0.5 g/l P less than 0.01). In the echocardiographic study we found a significant impairment in left ventricular relaxation (isovolumic relaxation time (IRT) 106 +/- 6 vs. 73 +/- 7 ms, P less than 0.01). Erythrocyte membrane microviscosity (0.253 +/- 0.004 vs. 0.225 +/- 0.003, P less than 0.05) was also increased in hypercholesterolemic patients. Finally we found that erythrocyte membrane microviscosity correlated with fasting plasma insulin levels (r = -0.46, P less than 0.03) and IRT (r = -0.52, P less than 0.01).

Adult↗
PubMed1992

Chronic magnesium administration enhances oxidative glucose metabolism in thiazide treated hypertensive patients.

In newly-diagnosed untreated (n = 24) and thiazide treated (n = 18) hypertensive patients erythrocyte ion content and plasma ion and metabolite levels were determined. Thiazide treated patients had lower arterial blood pressure, plasma ion levels, erythrocyte magnesium and potassium content but higher fasting plasma insulin (66 +/- 7 v 87 +/- 8 pmol/L P < .02), triglycerides (1.88 +/- 0.24 v 2.34 +/- 0.44 mmol/L P < .05), free fatty acids (0.68 +/- 0.11 v 0.81 +/- 0.18 mmol/L P < .05). Subsequently, in a double-blind fashion and in random order thiazide diuretic treated patients were assigned to two groups: the first (n = 9) taking magnesium (15.8 mmol/day) and the other (n = 9) a placebo. Each treatment period lasted 8 weeks. At the end of each treatment period, each patient underwent blood sampling for determination of erythrocyte ion content and plasma ion and metabolite levels and was submitted to an euglycemic hyperinsulinemic (1 mU/kg/min for 120 min) glucose clamp. In this latter test D-3-H glucose infusion and indirect calorimetry allowed determination of glucose turnover parameters and substrate oxidation respectively. Chronic magnesium administration (CMA) raised fasting plasma (0.79 +/- 0.03 v 0.83 +/- 0.02 mmol/L, P < .05) and erythrocyte (1.98 +/- 0.08 v 2.35 +/- 0.03 mmol/L, P < .01) magnesium content. Along with insulin infusion, CMA improved glucose uptake, glucose metabolic clearance rate, and oxidative glucose metabolism. In the multiple linear regression analysis of the pooled basal data (n = 42), erythrocyte magnesium content displayed an independent correlation with basal plasma insulin levels (t = -2.08, P < .05).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1992

Progressive impairment of left ventricular diastolic filling with advancing age: a Doppler echocardiographic study.

OBJECTIVE: To identify the sequence and significance of left ventricular filling abnormalities associated with progressive aging in humans. DESIGN: Cross-sectional study comparing three age groups. SETTING: Department of Geriatrics at University of Naples. PARTICIPANTS: Seventy-five healthy subjects in three age groups: 25 subjects from 25 to 45 years (Group I), 25 subjects from 46 to 65 years (Group II), and 25 subjects from 66 to 85 years (Group III). INTERVENTION: None. MAIN OUTCOME MEASURES: All underwent pulsed-doppler echocardiography under color guide to measure the following parameters: peak velocity flow for early (E wave) and late (A wave) mitral flow; A/E wave ratio; deceleration time of mitral flow (MDt); isovolumic relaxation time (IRT); ratio of velocity time integrals of the A wave to the velocity time integrals of the entire mitral spectrum (VTIA/VTIM). RESULTS: Peak velocity of the E wave was slightly lower in Group II and III compared to Group I; in contrast, peak velocity of the A wave was greater (P less than 0.005) in aged individuals. Also A/E wave ratio, MDt, and IRT were significantly greater with advancing age (P less than 0.01; P less than 0.05 and P less than 0.001, respectively). Finally, VTIA/VTIM tended to be greater in the oldest group, but not significantly so. CONCLUSIONS: Left ventricular relaxation is progressively impaired in late middle age and old age, presumably an early marker of cardiac aging. Increased left atrial pressure is compromised only in the oldest group, presumably representing a compensation for impaired left ventricular relaxation.

Adult↗
PubMed1991

Effectiveness of glibenclamide on myocardial ischemic ventricular arrhythmias in non-insulin-dependent diabetes mellitus.

Glibenclamide, a hypoglycemic sulfonylurea, is a blocker of the adenosine triphosphatase-modulated potassium ion channels. The opening of these channels in the myocardial cells, induced by acute myocardial hypoxia, can be responsible for ischemic ventricular arrhythmias. To evaluate the antiarrhythmic effects of this drug 19 non-insulin-dependent diabetic patients were selected. They had coronary artery disease and evidence on Holter monitoring of ventricular premature complexes or nonsustained ventricular tachycardia, or both, induced by transient myocardial ischemia. In all patients, 24-hour electrocardiographic monitoring was performed to evaluate the number and duration of myocardial ischemic events, the frequency of ventricular premature complexes and nonsustained ventricular tachycardia per minute of ischemia and the percentage of ventricular premature complexes versus total ischemic beats. Selected patients were classified in 2 groups: group A (9 patients) received metformin (placebo) and group B (10 patients) was treated with glibenclamide. On the fourteenth day patients underwent 24-hour control monitoring. Then a crossover between the 2 groups was made and a new Holter monitoring sequence was performed at the end of the second phase. Results indicate that glibenclamide significantly (p less than 0.001) reduced both the frequency of ventricular premature complexes and the episodes of nonsustained ventricular tachycardia during transient myocardial ischemia, but did not change the number and duration of acute myocardial ischemic attacks and did not reduce the spontaneous ventricular arrhythmias. Thus, glibenclamide appears to have an antiarrhythmic effect in preventing ventricular arrhythmias induced by transient myocardial ischemia.

Adult↗
PubMed1991

Coumarin anticoagulation during pregnancy in patients with mechanical valve prostheses.

Between January 1987 and December 1989, 20 female patients with one mechanical valve prosthesis (MVP) for at least 1 year postoperatively were studied while on coumarin therapy for the full length of pregnancy. In each case, caesarean section was scheduled for the 38th week. Patients were selected according to the following criteria: (1) prothrombin ratios remaining within the therapeutic range for more than 85% of their total estimations in the previous 12 months with mean daily doses of warfarin less than 5 mg; (2) stable cardiac status; (3) no previous obstetric diseases and (4) full acceptance of the risks involved in the protocol. The patients were in NYHA functional class I or II. Their ages ranged from 23 to 31 years (mean 26 +/- 3). Ten patients had a mitral prosthesis and 10 an aortic prosthesis. Among the 20 mechanical valve prostheses, 10 were Sorin, 6 Starr-Edwards, 2 Bjørk-Shiley, and 2 Lillehei-Kaster. Eighteen patients were in sinus rythm, 1 in chronic atrial fibrillation, and 1 had a permanent endocardial pacemaker. Nineteen were delivered by caesarean section: warfarin was withdrawn 48 h before surgery and resumed 24 h thereafter. One patient had premature spontaneous delivery at 36 weeks. The mean prothrombin ratio measured weekly in the 20 patients was 2.06 +/- 0.45 INR, using a mean daily warfarin dose of 4.1 mg +/- 1.63. The mean value of the prothrombin ratio during caesarean section for the 19 patients was 1.23 +/- 0.38 INR. In the 20 live births, the mean birth weight was 2.9 kg +/- 0.40.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

Hemodynamic changes in left ventricular function during acute coronary insufficiency: a Doppler echocardiographic study.

To define the availability of Doppler echocardiography in evaluating left ventricular hemodynamic changes induced by some clinical findings of acute coronary insufficiency, we selected 12 patients with angina and 32 affected by acute myocardial infarction. Doppler echocardiography was performed at hospital admittance and during recovery time. Left ventricular contractility was defined on the systolic aortic flow spectrum by measuring the aortic velocity maximum, the time to peak/left ventricular ejection time ratio, and the cardiac output. During the first examination, left ventricular contractility significantly decreased in patients with angina and in those with acute myocardial infarction. After the acute phase, these parameters slightly improved. Left ventricular diastolic filling was evaluated in the transmitral flow. A decreased E-wave velocity and an increased late component (A wave) with inversion of the E/A wave ratio were found in patients with acute myocardial infarction during the first examination. This morphology inverts when the patients stabilize. On the contrary, this ratio stayed above one during and after angina. In this study, we also defined the usefulness of the color Doppler method in setting up criteria to identify some early morphological complications of acute myocardial infarction in 12 patients with acute infarction and a new systolic murmur. This technique showed an ischemic rupture of the ventricular septum in five cases and mitral regurgitation in seven. The color Doppler method has allowed us to obtain a semi-quantitative assessment of the mitral regurgitation and the location of the ventricular septal defect.

Adult↗
PubMed1986

Noninvasive evaluation of left-to-right shunts by pulsed Doppler echocardiography.

The systemic and pulmonary blood flows and the ratio of pulmonary to systemic flow were noninvasively evaluated by pulsed Doppler echocardiography in 25 children with left-to-right shunts. Fourteen patients had atrial septal defect and 11 had ventricular septal defect. In patients with atrial septal defect, right ventricular stroke volume was obtained from the recordings of mean velocity flow and the diameter at the level of pulmonary valve in short-axis view. The left ventricular stroke volume was evaluated from the suprasternal approach by positioning the sample volume within the ascending aorta just above the valvar leaflets. In children with ventricular septal defect, the pulmonary blood flow was determined at the level of the mitral orifice, whereas the systemic blood flow was estimated from the ascending aorta. The systemic and pulmonary blood flows and their ratio determined by pulsed Doppler echocardiography in the 25 patients examined, were compared using simple linear regression analysis with the results obtained by cardiac catheterization. The ratio of pulmonary-to-systemic flow showed an excellent correlation in patients with atrial septal defect (r = 0.82) and in those with ventricular septal defect (r = 0.79). Our study validates the accuracy of cross-sectional Doppler echocardiography, especially for minimizing some possibility of errors in the presence of left-to-right shunts by employing new approaches.

Blood Circulation↗
PubMed1986

[Post-necrotic endoventricular thrombosis. Comparative evaluation of the diagnostic reliability of 2-dimensional echocardiography and cineventriculography].

The purpose of this study was to assess the relative diagnostic value of two-dimensional echocardiography (2D-Echo) and biplane left ventricular cineangiography (CV) for detecting the presence of left ventricular mural thrombi (LVT) in selected patients (pts) with left ventricular aneurysm (LVA). The Echocardiographic and Angiographic data of 19 pts selected from a group of 58 pts with coronary artery disease who underwent surgery for aorto-coronary bypass and/or aneurismectomy, were retrospectively examined. The presence of LVA was shown at surgery in all patients, located near the cardiac apex in 10 pts, at the level of the antero-septal wall of left ventricle in 7 pts and of the antero-lateral wall in 2 pts. In 11 of the 19 pts (57.9%) a LVT was identified at surgery. The thrombus was large (greater than 2 cmq) in 6 pts and small (greater than 2 cmq) in 5 pts. In 10 of the 11 pts with LVT 2D-Echo showed the thrombus prior surgery (sensitivity = 91.6%) whereas CV identified the thrombus only in 7 pts (sensitivity = 73.3%). No false positive diagnosis of LVT was made by the two techniques (specificity = 100%). Six large and 4 small thrombi (1 false negative) were identified by 2D-Echo; 6 large and 1 small thrombi (4 false negative) were identified by CV. In conclusion, 2D-Echo showed a significantly higher sensitivity for LVT than CV in patients with prior Acute Myocardial infarction, especially for small thrombi.

Adult↗