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F de Pádua

Publications and source records attributed to F de Pádua.

At least 19 recordsLinked to original sources
PubMed2000

[Acute effects of tobacco and vascular risk modulated by genetic factors].

Most studies regarding the acute effects of cigarette smoking refer to the higher sympathetic and adrenomedullary activity as a result of sympathetic ganglia and adrenal medulla nicotinic receptor activation. Although it is reasonable to suppose that the renin-angiotensin system might be activated, this possible effect of nicotine has not been studied. We have studied the effects of cigarette smoking on blood pressure, cardiac output, pulse pressure, renin-angiotensin system, kinins-NO, oxidative stress and insulin. Also, we have investigated if the variability of the biochemical parameters was dependent on genetic polymorphisms of the angiotensin converting enzyme and the acute phase protein haptoglobin. 39 normotensive individuals, 18 males and 21 females, of mean age 35.4 +/- 8.9 years were included in this study. Oxidative stress was dependent on the ACE I/D and Hp1/2 polymorphisms, with the ACE DD genotype and the Hp2-2 phenotype not showing variation in the anti-oxidant defense systems, and the ACE II-ID genotypes and Hp1-1 + 2-2 phenotypes showing a higher anti-oxidant response, hence a lower cardiovascular risk being predictable in the latter individuals.

Adult↗
PubMed1997

Comparison between dobutamine echocardiography and thallium-201 scintigraphy in detecting residual stenosis, ischemia, and necrosis in patients with prior myocardial infarction.

BACKGROUND: Following the first attempts to detect myocardial ischemia with two-dimensional echocardiography stress testing, pharmacologic stress using dobutamine infusion has become an alternative to echocardiography exercise testing for evaluation of coronary artery disease. It has been shown that stress echocardiography has a diagnostic accuracy similar to that of an exercise thallium test. Other studies, however, indicated that radionuclide myocardial perfusion imaging was more sensitive than exercise or pharmacologic stress echocardiography for detection of ischemia or jeopardized myocardium. HYPOTHESIS: The aim of the present study was to determine the ability of dobutamine stress echocardiography in comparison with thallium-201 scintigraphy to identify multivessel disease and the presence of myocardial scar and ischemia in 60 consecutive patients who suffered a first myocardial infarction (MI). METHODS: Patients were evaluated by coronary angiography and ventriculography, thallium-201 (201TI) tomographic scintigraphy, and dobutamine echocardiography within 3 months of a first MI. Forty-seven had Q-wave MI and 13 had non-Q-wave MI. Eleven patients were excluded from final analysis-7 because of failure to achieve target heart rate in spite of the use of atropine, and 4 because of high blood pressure following the infusion of dobutamine. RESULTS: Dobutamine echocardiography showed an overall sensitivity of 43% for detection of coronary artery lesions of 50-74% diameter stenosis and 201TI scintigraphy showed a sensitivity of 71%. For detection of lesions of > or = 75% diameter stenosis, dobutamine echocardiography showed a sensitivity of 52% and 201TI a sensitivity of 70%. Overall agreement between wall motion and myocardial perfusion for detection of necrosis and/or ischemia in the infarct area was 40.4% with a kappa coefficient of 0.09 (p = 0.13). For detection of ischemic myocardium outside the infarct zone, overall agreement was 78.6% with a kappa coefficient of 0.49 (p < 0.0001). CONCLUSION: Dobutamine echocardiography results showed a lower sensitivity than myocardial perfusion images in predicting multivessel coronary artery disease, and there was poor agreement between both methods in identifying necrosis or ischemia.

Coronary Angiography↗
PubMed1997

[The digital image archive--its clinical applications and importance in cardiology consulting by telemedicine].

The revolution in digital technology is rapidly changing the world of telecommunications. Its applications to Medicine, and in particular to Cardiology, offer enormous benefits since communication is an essential part of medical practice. The need to improve the management of medical information is critical because of the explosion of medical knowledge, and the need to provide comprehensive documentation on patient care. The availability of a network offers many possibilities for clinical, research and teaching activities. Relevant, up-to-date scientific information is instantly available for analysis and interaction. The authors review the issue of digital communications as well as its potential application to Telemedicine, and present their preliminary experience with digital analysis and storage of echocardiographic images.

Cardiology↗
PubMed1997

Dynamic three-dimensional echocardiography: a new era in ultrasound technology.

The use of noninvasive methods to visualise the heart has had an extraordinary development over the last decade, with echocardiography demonstrating a particularly fast growth. Despite its unquestionable role in the diagnosis of heart disease and in the management of cardiac patients, it does have some limitations, both in the morphological visualisation, as well as in the functional assessment of the heart, such as blood flow, quantification of intracardiac volumes, etc. The recent development of dynamic three-dimensional (3D) echocardiography from two dimensional images has opened new perspectives in the study of cardiac pathophysiology. There are basically two methods of displaying three dimensional data sets: (1) a two-dimensional display from individual selected cut planes (any-plane echocardiography) or from parallel short axis cuts; (2) a volume rendered technique: from any defined cut plane, different algorithms are applied to represent the information in space. There are several potential clinical applications of 3D such as the measurement and serial follow-up of left ventricular volumes; in valvular heart disease (the abnormalities can be delineated more precisely and in greater detail than conventional imaging, including a detailed definition of mitral apparatus in mitral stenosis), in mitral valve prolapse both leaflets can be seen from the left atrial view and in endocarditis it can aid in deciding when and how to intervene; in complex congenital heart disease, such as reconstruction of double outlet right ventricle, left-sided obstructive and regurgitant lesions and subaortic obstructive cases, in atrial and ventricular septal defects, displaying size, geometry and relationships to other structures; another expression of cardiac disorders are blood flow disturbances (visualisation of flows in 3D could allow a better qualitative and quantitative assessment of their size and severity; the pictures so far generated allow a good perception of the size and shape of mitral, aortic and tricuspid regurgitation jets, by examining them from a new perspective, it also has the potential to display the flow convergence zone and quantify the regurgitant volume). Recent studies have clearly demonstrated the feasibility of performing three-dimensional imaging in a variety of cardiac diseases, but continued development of ultrasound technology must be made to improve better image resolution. The prolonged acquisition time is the most important limiting factor that currently restricts the routine use of 3D echocardiography. The development of faster computers will shorten the time needed for image acquisition, postprocessing, and data analysis, contributing to the goal of easy access and wide use. With improvements in computer technology and production of interactive software, 3D echocardiography will provide a dynamic view of the surgical anatomy of the heart. Thus, the three-dimensional reconstruction concept has the potential to and diagnostic assessment of cardiac pathology in every facet.

Cardiovascular Diseases↗
PubMed1996

[Thrombolytic therapy in acute myocardial infarct--is it being used to the fullest?].

OBJECTIVE: To evaluate the experience with thrombolytic therapy (TT) in the treatment of patients with the discharge diagnosis of acute myocardial infarction (AMI). DESIGN: Retrospective analysis of the clinical records of patients with the discharge diagnosis of AMI, between May 1988 and December 1995. SETTING: Intensive Cardiac Care Unit (UCIM-Medicina IV) of Santa Maria University Hospital, Lisbon, Portugal. PATIENTS: 1319 patients, 958 men (73%) and 361 women, mean age 64 +/- 12 years. MAIN RESULTS: Thrombolytic therapy was administered in 391 patients (30%). Female patients received less thrombolytic therapy compared with male (17% vs. 34%; p < 0.001). Anterior wall infarction was more frequent (38%). Patients in Killip class I-II (77%) received more thrombolytic therapy than class III-IV (33% vs. 17%). The utilization rate of thrombolytic therapy increased from 25% in 1988 to 34% in 1995. Two major categories of patients were not treated with thrombolysis: 1) patients presented more than 12 hours after pain onset (38%); 2) patients without ST segment elevation or LBBB on the ECG presented (37%). Overall hospital mortality was 15.6%. The mortality in patients receiving thrombolytic therapy was significantly lower than in those excluded (9.4% vs. 18.2%; p < 0.001). CONCLUSION: Only 30% of patients with AMI receive TT. Of those excluded from this important therapeutic intervention, 75% had no ECG criteria or were outside the standard therapeutic "window". This significant group of patients need new diagnostic and intervention strategies.

Aged↗
PubMed1996

[Electrocardiographic changes after coronary angiography: effect of the contrast media used].

UNLABELLED: Prospective study to evaluate the influence of 2 different iodine contrasts (used in coronariography) on the electrocardiographic changes recorded after intra-coronary injection. MATERIAL AND METHODS: Sixty-six patients (pts) - 50 men and 16 women - 59 +/- 4 years underwent coronariography to confirm and/or evaluate coronary artery disease (CAD). Group I (33 pts) received a hyperosmolar contrast; group II received a low osmolarity contrast. The electrocardiograms were recorded during and until 20 seconds after intra-coronary injection, in standard leads and V5. Tracings were analysed regarding the development of: arhythmias, mean axis deviation and QRS enlargement - type A abnormalities; ventricular repolarization (ST/T) changes - type B abnormalities. ECG changes were compared with: 1. contrast used; 2. presence (or absence) of CAD; 3. correlation between type B abnormalities and the arteries affected. RESULTS: 1. a) Twenty nine pts (88%) of group I had A and/or B electrocardiographic changes, compared with 16 (48%) of group II (p < 0.01). b) There were type A changes in 13 pts of group I (39%) versus 3 pts (9%) of group II (p < 0.01). c) Type B changes were present in 25 pts (76%) of group I and in 20 pts (60%) of group II (p-NS). 2. a) Type A abnormalities were recorded in 13 of 48 pts with CAD (27%) against 3 of 18 (17%) cases with normal coronariography (p-NS). b) Type B abnormalities were present in 30 of 48 pts (63%) with CAD and in 10 of 18 cases (56%) of people with normal coronariography (p-NS). 3. In 21 pts with isolated right (or left) CAD, contrast injection in the right coronary artery induced type B ECG changes on the homo-lateral supplied territory in 14 cases, no change at all in 4 cases and changes in the contra-lateral area in only 3 pts. Injections in the left coronary artery produced similar results. CONCLUSIONS: 1. Hyperosmolar contrast produced significantly more electrocardiographic abnormalities, mainly type A, than low osmolarity contrast. This one may be, therefore, preferable. 2. Both types of electrocardiographic changes were equally recorded in pts with CAD and in people with normal coronariography. 3. Type B changes seem to be related with the location of the injection, irrespective of the presence or absence of coronary artery disease.

Adult↗
PubMed1994

[Stress echocardiography with dobutamine: the importance of adding atropine in inconclusive tests].

OBJECTIVES: To study the feasibility of adding atropine after dobutamine infusion in patients with known or suspected coronary artery disease not achieving 85% of predicted maximal heart rate. PATIENTS: We studied with dobutamine stress echocardiography 219 patients (174 men e 45 women; mean age +/- SD: 58 +/- 11 years), 126 patients with a previous myocardial infarction and 93 with angor. One hundred and thirty three (61%) also performed coronariography. METHODS: Dobutamine stress echocardiography protocol consisted of a step-wise infusion of dobutamine from 5 micrograms/kg/min to a maximal dose of 40 micrograms/kg/min or until a new or a worsening wall motion abnormality, 85% of predicted maximal heart rate or any indication for interruption. In patients not achieving any of these end points, intravenous atropine was administered up to 1 mg. Patients were divided in two groups: Group A: infusion of dobutamine alone and Group B: dobutamine plus atropine. RESULTS: With this protocol the test was interrupted in 41 patients (19%) because of adverse effects that were mild and short lived and resolved with discontinuation of the test. After dobutamine infusion 46% of the tests were nonconclusive, the majority were on beta blocker therapy. After atropine administration there was a significant reduction of the nonconclusive studies to 20% (p < 0.001). In patients with a normal rest echocardiogram the sensitivity and specificity of the test to diagnose significant coronary artery disease was respectively 89% e 100% after atropine. The capacity of the test to detect multivessel disease was also increased after atropine, allowing to reach a sensitivity of 85% and a specificity of 90%. CONCLUSIONS: Dobutamine stress echocardiogram supplemented with atropine is a safe and accurate method to diagnose significant coronary artery disease and to detect multivessel disease in patients with a previous myocardial infarction with rest wall motion abnormalities.

Aged↗
PubMed1993

Minimal residual coronary obstructions in patients who suffered a first myocardial infarction. A prospective study comparing coronary angiography and exercise thallium scintigraphy.

The purpose of the present study was to correlate the presence of minimal coronary obstruction (< or = 50%) assessed by coronary angiography with the presence of myocardial scar and ischemia detected by thallium-201 myocardial perfusion imaging. The study included 83 consecutive patients (74 men and 9 women) with a mean age 55.4 +/- 8.5 years who suffered a first myocardial infarction and did not undergo thrombolytic therapy. In all patients, coronary angiography, left ventriculography, and exercise thallium-201 tomographic scintigraphy were performed within 3 to 5 months of the myocardial infarction. Coronary arteriograms showed minimal residual obstructions in 37 (45%) patients. Of a total of 54 patients with < or = 50% obstruction, 18 showed persistent defects and 22 reversible defects on thallium scintigrams. The present study showing estimated angiographic stenosis of < or = 50% as being responsible either for myocardial scar or myocardial ischemia on postexercise thallium scintigrams leads us to conclude that percent value of stenosis does not accurately predict the pathophysiologic significance of coronary atherosclerotic lesions in patients who suffer a myocardial infarction. After a first myocardial infarction, coronary angiographies and thallium-201 scintigrams are complementary for an optimal treatment strategy for selected subsets of patients.

Adult↗
PubMed1993

Postexercise changes of the QTc interval in patients with recent myocardial infarction.

A lack of the QTc ratio decrease at maximal exercise is considered as an index of exercise-induced ischemia in patients with coronary artery disease. The authors studied 51 patients with recent myocardial infarction in order to evaluate the QTc changes with exercise in assessing the presence of remaining ischemic myocardium. All patients were submitted to exercise stress tests, coronary angiographies, and exercise thallium 201 scintigraphies within 3-5 months of the myocardial infarction. Of the patients studied, 18 showed one-vessel disease and 33 showed multivessel disease. All vessels were classified as patent or occluded. In all patients with reversible thallium 201 defects both at distance and in the infarct zone, the QTc interval following exercise either showed a prolongation or no change from the resting electrocardiogram. In patients with only fixed perfusion defects, the QTc shortened at the end of the test. This study showed a low sensitivity and specificity for inducible ST-segment depression compared with the delayed redistribution on the postexercise thallium 201 scintigram. QTc variations at the end of exercise electrocardiograms are valuable as a noninvasive, low-cost identification of residual ischemic myocardium in patients after myocardial infarction.

Coronary Angiography↗
PubMed1993

[Calcium antagonists in the treatment of congestive heart failure].

The authors present a revision of the clinical studies using calcium antagonists to treat chronic heart failure. They analyse cases where calcium antagonists seem to be of no use (and can even have an adverse effect), particularly in patients with significant left ventricular systolic dysfunction, with normal afterload, high levels of renin, very high levels of right atrium pressure or low sodium. On the opposite, patients with increased afterload or valvular regurgitation can receive some benefit, although care must be taken in the administration of this kind of drugs. New calcium antagonists may show more benefit because they seem not to stimulate the adrenergic system and do not have significant negative inotropic effects. They conclude with a reference to the multiple situations that can be the basis for heart failure, suggesting that probably, in the future, therapy shall be more individually tailored and that in some cases calcium antagonists can be included in such therapy.

Calcium Channel Blockers↗
PubMed1993

[The classic exercise test or by imaging? New applications of Doppler echocardiography].

Classic electrocardiographic exercise test was for many years the only stress modality to exercise the heart, and remains the most widely performed method for provoking ischemia. ST segment deviation on the ECG is the most often utilized marker of abnormal regional myocardial perfusion. But it has traditionally been considered to possess unsatisfactory accuracy in certain categories of patients, namely those with baseline ECG changes that preclude the diagnosis of coronary artery disease. To overcome these limitations, other stress modalities have been introduced recently, namely the radionuclide techniques like stress thallium or MIBI scintigraphy, utilizing inhomogeneous uptake of the radionuclide as a marker of abnormal regional myocardial perfusion, and represents a major improvement in diagnostic accuracy compared with exercise ECG. But these stress modalities are very expensive, and need radiation exposure. More recently stress echocardiography has been introduced and recommended by the American College of Cardiology as a valid and clinically useful technique, presenting several advantages over the radionuclide techniques: a relatively inexpensive test, provides immediate results, no radiation exposure. Because many patients cannot perform dynamic exercise, pharmacological stress testing (dipyridamole, adenosine, dobutamine) coupled with imaging techniques, in particular echocardiography has become very popular with high sensitivity and specificity for the non invasive diagnosis of coronary artery disease. The analysis of the results obtained from several studies, showed that these new stress modalities, are ready for routine clinical use.

Contrast Media↗
PubMed1991

Hereditary protein C deficiency and portal-vein thrombosis.

Inherited defects of the natural coagulation inhibitors predispose patients to thrombosis. These disorders have similar clinical presentations with a strong family history of thrombosis, episodes of recurrent venous thromboembolism, beginning in early adulthood. We report a case of upper gastrointestinal bleeding in a patient with portal hypertension due to portal-vein thrombosis secondary to hereditary protein C deficiency, an association that has seldom been reported.

Humans↗