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Luís Sargento

Publications and source records attributed to Luís Sargento.

8 recordsLinked to original sources
PubMed2004

Early detection of sympathetic myocardial denervation in patients with familial amyloid polyneuropathy type I.

INTRODUCTION: Type I familial amyloid polyneuropathy (FAP I) is an autosomal dominant inherited disorder due to a genetic defect in transthyretin and is characterized by deposition of amyloid in various organs and tissues. The principal manifestations are related to polyneuropathy and dysautonomia. The aim of this study was to assess cardiac involvement and to correlate the findings with neurological status. METHODS: 34 patients with FAP (15 male and 19 female; mean age 43 +/- 15 years) underwent I123-labeled metaiodobenzylguanidine (MIBG) myocardial scintigraphy in order to evaluate cardiac sympathetic innervation. In addition they underwent ambulatory blood pressure monitoring (ABPM) and two-dimensional and Doppler echocardiography. Neurological involvement was quantified according to a neurophysiologic score (EMG; 0 = no abnormality and 100% = maximal disability). RESULTS: The mean value of cardiac MIBG uptake was 1.75 +/- 0.5 (normal = 2.6 +/- 0.3) and correlated inversely with the EMG score (r = -0.67; p = 0.001). In 27 (79%) of the 34 patients there was a decrease in MIBG accumulation, in 18 (53%) an alteration in the circadian BP pattern and/or an increase in systolic and/or diastolic BP loads at night, and in 17 (50%) left ventricular hypertrophy and/or diastolic dysfunction. Twenty-two patients were symptomatic and had a mean EMG score of 37.7 +/- 25% (group I). The remaining 12 were asymptomatic and without neurological involvement (group II). Group I was characterized by older age (48 +/- 15 vs. 33 +/- 10.2 years, p = 0.01), lower MIBG uptake (1.5 +/- 0.4 vs. 2.2 +/- 0.5, p = 0.001), higher systolic (129 +/- 16 vs. 119 +/- 6 mmHg, p = 0.01) and diastolic daytime BP (82 +/- 10 vs. 76 +/- 6 mmHg, p = 0.05), and higher systolic (119 +/- 17 vs. 105 +/- 7 mmHg, p = 0.01) and diastolic nocturnal BP (71 +/- 11 vs. 62 +/- 9 mmHg, p = 0.01) than patients in group II. In 21/22 patients in group I and in 6/12 in group II there was a decrease in cardiac MIBG activity. Sixteen patients in group I and 2 in group II had abnormal circadian BP pattern. Left ventricular hypertrophy was only seen in group I. CONCLUSIONS: Patients with FAP have a high incidence of cardiac denervation and an abnormal circadian BP pattern. These alterations in cardiac autonomic function precede the development of clinical manifestations and may be an important factor in determining the optimal timing for liver transplantation, which is currently the only way to control the progression of the disease.

Adult↗
PubMed2004

Role of real-time myocardial contrast echocardiography in the assessment of viability after acute myocardial infarction and angioplasty.

OBJECTIVE: To assess the role of myocardial contrast echocardiography (MCE) in early identification of myocardial viability in patients with residual segmental dysfunction after myocardial infarction and primary angioplasty (PA), in comparison with dobutamine stress echocardiography (DSE), using late functional recovery as gold standard. DESIGN: Prospective study for comparison of the two methods. SETTING: Hospital. PATIENTS: 17 patients (11 male, 53 +/- 11 years old) were consecutively included, with a first myocardial infarction and PA, with residual segmental akinesis or dyskinesis and good echocardiographic window. METHODS: All patients underwent: a) baseline echocardiographic study, MCE, and DSE obtained at 4.0 +/- 1.2 days after PA; b) late echocardiographic study performed at 4.4 +/- 0.8 months after PA. MCE was performed with Optison, administered as a slow infusion via a peripheral vein and a modality of real-time perfusion imaging with power pulse inversion and flash and subsequent data acquisition of triggered end-systolic images. Segmental contractility and perfusion were assessed using a 16-segment model. Perfusion assessment was qualitative (three perfusion patterns) and quantitative (ratio of maximal intensity between dysfunctional segments and contralateral normal segments). The viability criterion for MCE was defined as homogenous enhancement in 50% of wall thickness in each segment. The standard criterion for myocardial viability was defined as late functional recovery. 6. RESULTS: Viability was present in 56 (63.6%, Group 1) of dysfunctional segments and was absent in the remaining 32 (36.4%, Group 2). The sensitivity of DSE for viability was 80.0%, while specificity was 86.5%. The positive and negative predictive values were, respectively, 91.8% and 69.6%. MCE yielded a sensitivity of 96.5% and specificity of 78.1%, while positive and negative predictive values were respectively 86.2% and 94.1%. With the two methods together, the positive predictive value was 90.3% and negative was 80.0%. The intensity ratio was higher for viable segments (Group 1) in comparison with non-viable ones (Group 2; p<0.005). 7. CONCLUSIONS: This study showed a potentially valuable role for MCE in assessing viability in patients with myocardial infarction and PA. In comparison with DSE, MCE yielded a higher negative predictive value as well as a high positive predictive value. The use of both methods together is promising as a useful tool for early assessment of viability after primary angioplasty.

Angioplasty, Balloon, Coronary↗
PubMed2004

Plasma N-terminal pro-brain natriuretic peptide: a marker of left ventricular hypertrophy in hypertrophic cardiomyopathy.

BACKGROUND: B-type natriuretic peptide is secreted mainly in the left ventricle in response to elevated wall tension. Plasma levels of the peptide correlate positively with cardiac filling pressures, making it an excellent marker for the presence of left ventricular dysfunction. In hypertrophic cardiomyopathy, enhanced production of B-type natriuretic peptide is observed. However, the relationship of the various structural and functional features present in the disease with the high plasma levels described is not yet fully clarified. In the present study, we prospectively assessed in hypertrophic cardiomyopathy the relationship of plasma NT-proBNP levels with the extent of left ventricular hypertrophy, presence of left ventricular outflow obstruction and echocardiographic parameters of left ventricular diastolic function. METHODS: The study population included 190 individuals: 53 patients with hypertrophic cardiomyopathy and well-preserved left ventricular systolic function (group A), 92 healthy relatives with no disease expression (group B), and an additional group of 46 healthy volunteers (group C) as controls for NT-proBNP levels. Groups A and B were characterized clinically and by echocardiography and compared with each other. Plasma NT-proBNP levels were measured (ECLIA-Elecsys proBNP) and compared in the 3 groups of individuals included in the study. In hypertrophic cardiomyopathy patients, correlation was sought between NT-proBNP levels, NYHA functional class and echocardiographic data. RESULTS: Groups A and B differed (p < 0.001) in septal thickness, maximal wall thickness, left ventricular hypertrophy score, left atrial size, left atrial fractional shortening, derived transmitral filling indices and plasma NT-proBNP levels (group A: 909.9 +/- 1554.2 pg/ml; group B: 40.7 +/- 45.1 pg/ml). Left ventricular diastolic size and pulmonary venous flow velocity-derived indices were similar in the 2 groups. NT-proBNP levels in group B and C (39.4 +/- 34.5 pg/ml) were similar (p = NS). In hypertrophic cardiomyopathy patients, NT-proBNP levels correlate directly with NYHA functional class (r = 0.56, p < 0.001), septal thickness (r = 0.53, p < 0.001), maximal wall thickness (r = 0.59, p < 0.001), left ventricular hypertrophy score (r = 0.63, p < 0.001), left atrial size (r = 0.32, p = 0.023) and mitral deceleration time (r = 0.46, p = 0.001) and inversely with left atrial fractional shortening (r = -0.41, p = 0.005). Functional class also correlates directly with left ventricular hypertrophy score (r = 0.39, p = 0.006), with the most symptomatic patients having the highest scores. CONCLUSIONS: In hypertrophic cardiomyopathy, plasma NT-proBNP levels depend mainly on the severity of left ventricular hypertrophy rather than on the presence of obstruction. Measurement of the peptide may help in the clinical characterization and follow-up of patients with this disease.

Adolescent↗
PubMed2002

[Biohemorheologic factors and cardiovascular events curve in survivors of transmural acute myocardial infarct--24-month follow-up].

INTRODUCTION: Previous reports have shown several biohemorheological disturbances in acute myocardial infarction (AMI), either in the acute phase and after hospital discharge. There is no clearly established relationship between these parameters and the patients' clinical outcome. OBJECTIVE: To evaluate in transmural AMI survivors, a relationship between biohemorheological parameters and the cardiovascular events curve during a 24 month follow-up period. METHODS: Sixty-four consecutive patients (58.0 +/- 12.0, 59 men), transmural AMI survivors (30 anterior and 34 inferior) were included in the study. Clinical follow-up was 24 months (at 6, 12 and 24 months). The following cardiovascular events (CVE) were collected: cardiovascular death, stroke, AMI, unstable angina, embolism. We determined, at hospital discharge, these biohemorheological parameters: plasma viscosity, fibrinogen, PAI-1 inhibitor, leukocyte count, C protein (C Pt), erythrocyte aggregation (EA). For each parameter we determined the 25, 50 and 75 percentiles and other significant cut-off point, grouping patients according to these values. STATISTICS: Group t test, Kaplan-Meier survival curve (with the log rank test), and Cox logistic regression. RESULTS: (1) Patients with CVE (n = 19) during the 24 months of clinical follow-up had at hospital discharge higher leukocyte count (p < 0.001), lower C Pt (p < 0.01) and lower EA (p < 0.05). (2) The higher the percentile of the leukocyte count higher the probability for a CVE. Patients with leukocyte count above the 50 percentile had 6 times more CVE (p < 0.01); (3) The higher the C Pt lower the risk for a CVE. Patients with C PT lower than the 50 percentile had 9 times more risk for a CVE (p < 0.01), and those above the 75 percentile had no CVE (p < 0.01). (4) For the EA we identified a cutoff point (= 14.5), independent of the percentiles values. Patients with EA below 14.5 had six times more CVE. By multivariate analyses, we identified leukocyte count and C Pt as independent risk predictive factors (p < 0.05). CONCLUSION: In this group of transmural MI survivors a relationship was established between some biohemorheological (leukocyte count, C Pt, EA) and the CVE curve during 24 months of clinical follow-up.

Blood Viscosity↗
PubMed2002

Evaluation of aortic stenosis severity: role of contrast echocardiography in comparison with conventional echocardiography and cardiac catheterization.

OBJECTIVES: To evaluate the role of contrast Doppler echocardiography in the assessment of aortic stenosis severity, in comparison with the conventional method and using the catheterization study as the gold standard. STUDY DESIGN: Prospective comparative study. SETTING: Echocardiography Laboratory of Cardiology Department. POPULATION: We included 36 consecutive patients, 20 male, aged 67 +/- 11 years, referred for catheterization study to evaluate aortic stenosis severity. METHODS: All patients underwent conventional and contrast Doppler echocardiography and catheterization study. For contrast Doppler, we used Levovist (300 mg/ml infusion). We analyzed the following echocardiographic parameters: a) left ventricle dimensions, wall thickness and function; b) aortic valve morphology; c) post-stenotic aortic valve flow--peak velocity, velocity-time integral, peak gradient, mean gradient; d) left ventricle outflow tract flow--peak velocity, velocity-time integral; e) aortic valve functional area; f) acquisition time and Doppler signal intensity for post-stenotic aortic valve flow. Catheterization parameters analyzed: a) peak aortic valve gradient; b) mean aortic valve gradient. RESULTS: Contrast Doppler yielded higher peak gradients than conventional Doppler (85.6 +/- 30.2 vs 72.6 +/- 26.1 mmHg, p < 0.001), as well as higher mean gradients (51.4 +/- 19.0 vs 44.2 +/- 15.9 mmHg, p < 0.001). Peak gradients obtained with contrast Doppler correlated with those obtained invasively (r = 0.88, p < 0.001), although the values were higher (85.6 +/- 30.2 vs 73.6 +/- 32.0 mmHg, p < 0.001). There was no difference between mean contrast Doppler gradients and mean catheterization gradients, which showed a high correlation (r = 0.89, p < 0.001). There was no difference between peak and mean gradients obtained by conventional Doppler and invasively, which yielded correlations of 0.73 and 0.75, respectively (p < 0.001). The sensitivity of contrast Doppler for detection of severe aortic stenosis was 100% for peak gradient and 84% for mean gradient, while for conventional Doppler it was 68% and 58%. The specificity of contrast Doppler was 65% for peak gradient and 88% for mean gradient, while for conventional Doppler it was, respectively, 58% and 88%. Acquisition time for aortic flow visualization was lower (p < 0.001) and flow intensity higher for contrast Doppler, in comparison with conventional Doppler. CONCLUSIONS: In this study, contrast Doppler yielded high correlations with invasive data and higher sensitivity and specificity for detection of severe aortic stenosis than conventional Doppler. It is a useful method for evaluation of aortic stenosis severity.

Adult↗
PubMed2002

Long-term prognostic value of the hemorheological profile in transmural myocardial infarction survivors: 60-month clinical follow-up.

UNLABELLED: Previous reports have shown several hemorheological and hemostatic abnormalities in acute coronary syndrome survivors. Some of these abnormalities were related to cardiovascular events during a 24-month follow-up. The aim of the present work is to evaluate, in transmural myocardial infarction survivors, the long-term (60 months) prognostic value of the biohemorheological profile determined at hospital discharge. Sixty-four patients (59 men), mean age of 58 +/- 12.0 years, transmural myocardial infarction survivors, were prospectively studied for 60 months (32.0 +/- 17 months, median 33 months). The following cardiovascular events (CVE) were analyzed: death, non-fatal infarction, unstable angina, and stroke. Twenty-nine patients had a CVE (nine died). The following parameters were determined at hospital discharge: plasma viscosity, whole blood viscosity, erythrocyte membrane fluidity, erythrocyte aggregation, protein C, plasminogen inhibitor type I (PAI-1), leukocyte count and elastase. The quartiles were determined for each parameter, grouping patients according to these values. STATISTICS: Group-t-test, Kaplan-Meier survival curve (with log rank test), and Cox logistic regression. RESULTS: 1) Leukocyte count (p < 0.01), protein C activity (p < 0.05) and erythrocyte membrane fluidity (p < 0.05) were predictors of the CVE curve; 2) The higher the value of the leukocyte count quartile, the higher the risk for a CVE (p < 0.05). Patients with a leukocyte count above the median had 4 times more risk for a CVE; 3) The lower the protein C activity, the higher the risk for a CVE. Those with protein C activity lower than the lowest quartile had double the risk; 4) The higher the membrane polarization value (membrane rigidity), the higher the risk of a CVE; 5) By multivariate analysis the 3 parameters were independent predictors of a CVE. CONCLUSION: In the present group of transmural myocardial infarction survivors a close relationship was established between hemorheologic, hemostatic and inflammatory factors and the cardiovascular events curve during long-term follow-up.

Female↗
PubMedDate not supplied

Myocardial perfusion and angioplasty. Comparison of myocardial contrast echocardiography and scintigraphy.

OBJECTIVES: To estimate the efficacy of myocardial contrast echocardiography (MCE) by harmonic power imaging (HPI), in evaluation of perfusion in one-vessel coronary disease treated by angioplasty, using myocardial scintigraphy as gold standard. STUDY DESIGN: Prospective comparative study. SETTING: Ambulatory. POPULATION: We included 33 patients (pts), aged 53.5 +/- 9 years, 27 male. INCLUSION CRITERIA: pts with one-vessel coronary disease (> or = 70% stenosis), with indication for angioplasty; sinus rhythm; good echocardiographic window with harmonic imaging. Exclusion criterion: previous myocardial infarction. METHODS: All patients underwent myocardial scintigraphy and HPI together with stress echocardiography, both followed by angioplasty (stenting in ten). HPI and myocardial scintigraphy were repeated, in all patients, at three months after intervention. Ten patients were re-assessed by coronary angiography for ischemia on the scintigraphic study. For the HPI exam, Levovist was selected as contrast and dipyridamole as stress agent (0.56 mg/kg). Perfusion was assessed visually and classified by HPI and scintigraphy studies as: 1 (normal), 2 (reduced), or 3 (absent). For analysis, the left ventricle was divided into 16 segments. RESULTS: Of the 43 coronary angiograms performed (ten at three months after angioplasty), 38 showed 70% stenosis, none occlusive or subocclusive. We analyzed 1056 left ventricle segments, from 66 HPI and myocardial scintigraphy studies (before and after angioplasty). Analysis was impossible or doubtful in 4.9%. Baseline and stress HPI detected 216 perfusion abnormalities. Global concordance between the segmental perfusion score obtained by HPI and scintigraphy was 66.2%, which became 76.3% when two groups were considered: a) score 1 b) score 2 and 3 together. In comparison with scintigraphy, HPI sensitivity for detection of perfusion abnormalities was 79.3% (higher for anterior septum, anterior and lateral wall) and specificity was 91.4% (higher for septum, inferior wall and apical segments). HPI correctly identified the location of coronary stenosis in 73.5% of patients. CONCLUSIONS: In our study, HPI was a feasible and promising method for assessment of perfusion in one-vessel coronary disease and chronic ischemia. In comparison with myocardial scintigraphy, a high concordance for perfusion score was found, as well as high sensitivity and specificity for detection of perfusion abnormalities.

Adult↗