Search PubMed⌕ Search

Biomedical subjects

R Seabra-Gomes

Publications and source records attributed to R Seabra-Gomes.

At least 91 records · Page 5Linked to original sources
PubMed1995

Atrioventricular valve repair using externally adjustable flexible rings.

Initial results obtained with a new flexible ring, adjustable from outside of the heart after interruption of extracorporeal circulation, are presented. Twenty-five rings have been inserted in 20 patients, 14 in the mitral position and 11 in the tricuspid position. In 8 of the 14 patients receiving mitral annuloplasty, other standard mitral valve repair techniques were used. Adjustment, assisted by intraoperative transesophageal color Doppler echocardiography, was done for 10 (71%) of the mitral rings and for 8 (73%) of the tricuspid rings. Residual mitral regurgitation disappeared or became minimal in 9 (90%) patients, and a mild regurgitation remained in 1. In all patients who received tricuspid rings regurgitation was abolished after the adjustment. There was no hospital or late mortality. After a maximum follow-up of 6 months results are comparable in the tricuspid and mitral positions and echocardiographic evaluation revealed stable competent valves in all patients but one, who underwent reoperation because of failure of a mitral valve chordae shortening procedure. The use of externally adjustable rings for the mitral and tricuspid valves is a safe alternative for atrioventricular valve annuloplasty and has the additional advantage of reducing postrepair regurgitation.

Adolescent↗
PubMed1995

[The evolution of the arterial pressure during a stress test in patients with hypertrophic myocardiopathy].

OBJECTIVES: To study the exercise blood pressure response in patients with hypertrophic cardiomyopathy (HC) and its relationship with sudden death. DESIGN: Retrospective study. POPULATION: We studied 51 patients (P) with HC: 18 women and 33 men. Their average age was 45 +/- 14 years, with a mean follow-up of 55 +/- 37 months. METHODS: Every patient had been subjected to a treadmill stress-test, a 24-hour Holter monitoring and an echocardiographic examination. Particular emphasis was given to blood pressure increments (BPI) during stress-test, the existence of premature ventricular contractions with a frequency of 10 or more per hour (PVC > or = 10), the occurrence of couplets (C) and/or non-sustained ventricular tachycardia (NSVT) on a 24-hour Holter. Finally, the finding of systolic anterior motion (SAM) of the mitral valve, in the routine echocardiogram, was valued. RESULTS: Four patterns of BPI were identified: "1": normal evolution (27 P); "2": plateau type increment (16 P); "3": fall in blood pressure during exercise (6 P); "4": abnormal BPI during recovery (2 P). Two groups were considered: group N-normal BPI, group A-patients with abnormal blood pressure responses. There were no significant differences among therapeutic agents, between the two groups, when the stress-test was performed. SAM was found in 21 P. Only 8 P registered ventricular arrhythmias, half of them with NSVT. No statistical relations were found between BPI and P age, the presence of SAM, PVC > or = 10, C, or NSVT. We found 78% of P in group N in NYHA class I. In contrast, in group A only 46% were in class I (p = 0.04). Only one death, of non cardiac cause, occurred (group A). CONCLUSIONS: There is a large number of patients with HC and abnormal BPI. This is, seemingly, not influenced either by a dynamic left ventricular gradient or by ventricular ectopic beat occurrence. However, a relation appears to exist between the abnormal response and functional class, not explained by the usual (noninvasive) clinical tests.

Adult↗
PubMed1995

[Response of the left ventricular ejection fraction,assessed by by radionuclide angiography, to inotropic stimulation: its relationship with the reversibility of perfusion defects in thallium-201 scintigraphy with overload-reinjection protocol].

BACKGROUND: Reversibility of perfusion defects and left ventricular (LV) ejection fraction (LVEF) response to low-dose catecholamines may reflect complementary aspects of myocardial viability, in patients with CAD and LV dysfunction in whom revascularization is considered. OBJECTIVE: To evaluate the relationship between LVEF response to inotropic stimulation with adrenaline (delta LVEF) and myocardial perfusion. DESIGN AND SETTING: Prospective study in a cardiology department with referral for revascularization and transplantation. PATIENTS: 45 patients (pt) with compromised LVEF (< 45%) after myocardial infarction (MI). METHODS: Radionuclide ventriculography at baseline and during graded adrenaline infusion until 12 micrograms/min: an empirical cut-off value of delta LVEF of 8% was used to define groups with (CR+) or without (CR-) contractile reserve. Stress-reinjection 201TI SPECT: perfusion was classified with a weighted score based on visual analysis of extent and intensity of thallium uptake in five major myocardial segments, with results expressed as percent of myocardium classified as normal (%N), with fixed defects (%F), and with reversibility (%R). MAIN RESULTS: Groups CR+ (23 pt) and CR- (22 pt) had similar baseline LVEF (29.6 +/- 7.4 and 26.4 +/- 8.1), while delta LVEF was respectively 13.6 +/- 4.6 and 2.9 +/- 3.3. When compared to the other group, CR+ patients had, in average, 1.0 segment more with definite reversibility and 1.6 segments less with fixed defects; in terms of percentage of myocardium, CR+ patients had more extensive reversible areas (%R: 15.3 +/- 11.7 vs 4.7 +/- 5.0, p < 0.001), smaller irreversible areas (%F: 30.7 +/- 14.5 vs 45.6 +/- 16.1, p = 0.02) and similar extent of normal areas (54.0 +/- 14.6 vs 49.7 +/- 16.4). Patients with more extensive fixed defects had worse delta LVEF in response to adrenaline (p < 0.002, r = -0.45). Greater %R was positively correlated with delta LVEF (p < 0.02, r = 0.35). In all patients, delta LVEF with adrenaline was superior or equal to (%R/2)-10. No patient with %R > or = 15 had delta LVEF < 8%. However, ten patients had delta LVEF > or = 8% despite lesser degrees of %R. CONCLUSION: Our data suggest a clear association between myocardial inotropic reserve and the extent of potentially viable myocardium (as evaluated by stress-reinjection thallium SPECT), in patients with left ventricular dysfunction after myocardial infarction. Further assessment is needed to clarify the relative role of radionuclide ventriculography with inotropic stimulation in viability evaluation, notably with inclusion of regional wall motion information and with reassessment of patients after revascularization, when performed.

Adult↗
PubMed1995

[Diagnosis of ischemia and survival after myocardial infarction using perfusion scintigraphy with exercise thallium-201. Relationship with electrocardiographic and angiographic findings].

OBJECTIVE: To review the experience of the laboratory on exercise-redistribution thalium-201 scintigraphy after myocardial infarction, and to compare scintigraphy results with those of exercise test and coronary angiography. DESIGN/SETTING/PATIENTS: Retrospective analysis of data from scintigraphy, exercise test and coronary angiography from all patients evaluated after myocardial infarction at Nuclear Medicine Department of Instituto do Coração with treadmill exercise-redistribution thallium-201 SPECT, if they were also submitted to cardiac catheterization. These criteria were met by 185 patients, studied between March 1988 and July 1993. MATERIAL AND METHODS: Micro-Delta system with a Siemens Orbiter gamma camera. Visual analysis of intensity and reversibility of perfusion defects in 5 segments per patient, using oblique reconstruction of images. RESULTS: Perfusion defects were found in 97% of patients and in 418/925 analysed segments. Variable degrees of reversibility were found in 78% of patients. On patients with single-vessel disease, vessel occlusion was associated with a slightly higher prevalence of reversibility (81% vs 71%; ns), and, for anterior infarcts, also with a higher prevalence of defects in areas supposed to be remote territories (44% vs 15%, p < 0.05). For 159 patients with a conclusive exercise test, ability of exercise test in diagnosing defects with reversibility was studied. Negative predictive accuracy of exercise test was poor (33%). Angina was 86% specific. Use of isolated ST depression, depression plus elevation or isolated ST elevation as criteria for a positive test result in a progressive improvement of sensitivity, but at cost of a decrease in specificity, more marked when using isolated ST elevation. CONCLUSIONS: Thallium scintigraphy revealed perfusion defects with some degree of reversibility in a large number of patients studied after myocardial infarction, even when considering single-vessel disease or occluded infarct-related artery. Electrocardiographic treadmill exercise test had a poor negative predictive accuracy, being reasonably sensible in multivessel disease, but poorer in single vessel disease. After infarction, typical angina should probably be also considered as criterion for ischemia, regardless of electrocardiographic changes. In a perspective of eventual use of revascularization after infarction, thallium-201 scintigraphy is a valuable tool, and should probably be considered in most patients.

Adult↗
PubMed1995

[Effectiveness and safety of coronary vasodilation with adenosine triphosphate with thallium-201 for the diagnosis of coronary disease].

OBJECTIVE: To evaluate the accuracy and safety of pharmacologic stress testing with adenosine triphosphate (ATP) associated with thallium-201 scintigraphy for detection of coronary artery disease. PATIENTS: We studied 44 patients, 35 male and 9 female with a mean age of 59 + 9 years. Previous myocardial infarction was present in 15 patients. Thirty-two patients underwent coronariography that revealed coronary artery disease in 28 patients. METHODS: ATP (Stryadine) was infused at a rate of 140 micrograms/kg/min for 6 minutes and 2 mCi of thallium-201 was injected at the third minute. Stress and redistribution SPECT acquisitions were performed respectively 5-10 minutes and 4-6 hours after ATP infusion. RESULTS: The incidence of side effects was 77% and chest pain was the most frequent (45%). Dyspnea occurred in 2 patients and only one patient presented transient first degree AV block. No serious or severe side effect occurred. In patients without myocardial infarction 14 of 16 patients with significant coronary artery disease had reversible perfusion defects demonstrated by ATP thallium-201 scintigraphy (sensitivity 88%) and all of 4 patients without significant coronary artery disease had normal myocardial perfusion (specificity 100%). The overall accuracy for detecting the presence of coronary artery disease was 90%. The test demonstrated an overall accuracy of 88% for detecting left anterior descending artery disease, 91% for circumflex artery disease and 80% for right coronary artery disease. CONCLUSIONS: Pharmacologic stress with ATP associated with thallium-201 scintigraphy, is a safe and high accurate alternative to dipyridamole and adenosine for the diagnosis of coronary artery disease.

Adenosine Triphosphate↗
PubMed1994

[Does the modified Bruce protocol induce physiological stress equal to that of the Bruce protocol?].

OBJECTIVE: To determine if the physiological stress induced by the modification of Bruce protocol used in our hospital is equivalent to the original protocol. DESIGN: Retrospective analysis of clinical history, physical examination and stress test of apparently healthy individuals submitted to cardiac check up. SETTING: Outpatient private cardiological clinical. PARTICIPANTS: Sequential sampling of 80 individuals apparently healthy, submitted to cardiac check-up between April 1988 and September 1992. MATERIAL AND METHODS: Comparison of heart rate, blood pressure and double product progression, as well as time of exercise of individuals studied by the Bruce protocol (group A: n = 51) with the same data of individuals tested by the modified Bruce protocol (group B: n = 29). MEASUREMENTS AND MAIN RESULTS: The first stage of group A protocol provokes a superior physiologic stress than group B protocol, since there are bigger increments on heart rate (28.8 +/- 9.9 vs. 20.2 +/- 11.2 bpm; p < 0.01), blood pressure (27.0 +/- 11.3 vs. 14.3 +/- 11.4 mmHg; p < 0.0001) and, consequently, higher double products. In submaximal stages with the same speed and grade on the treadmill the hemodynamical stress is similar in both groups. At peak exercise, group A attains higher values on systolic blood pressure (197.1 +/- 9.5 vs. 188.8 +/- 10.4 mmHg; p < 0.001), double product (34330.4 +/- 2191.8 vs. 33060.9 +/- 2049.8; p = 0.01) and corrected exercise time also higher than estimated (929 +/- 91 vs. 818 +/- 94 sec; p = 0.02). It could be found that more individuals on group A (76% vs. 48%; p = 0.02) could complete the stage of 6.8 Km/h x 16% (stage IV on Bruce protocol and V on modified Bruce protocol. CONCLUSIONS: Modified Bruce protocol has a lighter initial increment, but decreases moderately the capacity of peak exercise due to peripheral fatigue secondary to the first stage of low intensity. Bruce protocol has a higher initial increment but permits to attain higher peak exercise intensities. Bruce protocol seems more adequate to individuals with good physical capacity and the modified Bruce protocol to individuals moderately limited in their functional capacity due to bad physical fitness or illness.

Adult↗
PubMed1994

[Occlusion of the common branch of the left coronary artery. Clinical and angiographic characteristics and review of the literature].

The clinical and angiographic aspects of seven patients with left main stem coronary artery occlusion diagnosed within the first ten thousand coronary angiographies performed at our Hospital, are reported. The prevalence found (0.07%), is similar to that previously described (0.03 to 0.42%). Left main coronary artery occlusion is always an acute phenomenon with potentially very severe consequences. The existence of previously well developed collateral circulation from the right coronary artery, may avoid the occurrence of extensive acute myocardial infarction with cardiogenic shock and death, which otherwise follows the acute occlusion. Once diagnosed, coronary artery bypass surgery is the first choice treatment, although coronary angioplasty can be performed as a bridge for surgery, or as an alternative, if surgery is not available or is not recommended, int he acute setting of myocardial infarction. Three of our patients underwent successful angioplasty, one electively and two as an emergency during acute myocardial infarction with cardiogenic shock, and five had coronary surgery, one after previous angioplasty due to restenosis. There are only three long term survivors. In our small experience, the severe hemodynamic deterioration after left main occlusion is the major risk factor for mortality, which can only be avoided by early angiographic diagnosis.

Adult↗
PubMed1994

[A retrospective study of a population with intermittent atrial fibrillation].

OBJECTIVE: To analyse a population with intermittent atrial fibrillation, comparing the clinical characteristics of patients with the idiopathic form with those with structural pathology. DESIGN: Intermittent atrial fibrillation retrospective study. SETTING: Arrhythmology outpatients clinic of the cardiac department. PATIENTS AND METHODS: Retrospective study of a population of 59 patients with intermittent atrial fibrillation referred to the arrhythmology outpatients clinic of the cardiac department. Forty patients were male and nineteen female with a mean age of 51 +/- 13 years. Idiopathic atrial fibrillation group with 18 patients was compared with the 41 patients group with identifiable pathology. Atrial fibrillation was recognised by 12 lead ECG and 24 hours ambulatory Holter monitoring. Clinical and echocardiographic parameters were analysed. Complications and the efficacy of anti-arrhythmic therapy were referred. MAIN RESULTS: In the studied population, mean age at the identification of atrial fibrillation was lower in the idiopathic group than in the group with identifiable pathology. It was 36 +/- 12 years in the first group and 45.2 +/- 13 in the second. Left atrium dimension was 38.1 +/- 4 mm in the first group and 42.5 +/- 9 mm in the second (p = 0.04). In the group with mitral valvulopathy, left atrium dimension was 45.5 +/- 11 mm, also significantly different from patients with the idiopathic form (p = 0.012). Statistically significative difference between those groups was not found for left ventricular end-diastolic dimension and shortening fraction. Mean follow-up was 3 years with a range between 7 months and 10 years. Effective therapeutic control was obtained in 35 of 59 patients (59.3%). Six were from the idiopathic group (33.3%) and 29 from the group with identifiable pathology (70.7%). Control was not reached or was only partial in 24 patients (40.7%), belonging 66.7% to the first group and 29.3% to the second (p = 0.016). No embolic phenomenon was documented in the idiopathic not anti-coagulated group. Four embolic complications (9.8%) were observed in the group of identified pathology. Three of then were related with mitral valvulopathy and were submitted to effective anti-coagulation therapy. CONCLUSIONS: Patients with idiopathic intermittent atrial fibrillation are younger, with smaller left atrium dimension (mainly in relation to those with mitral valve disease) but are more resistant to anti-arrhythmic therapy. They have a trend to less thromboembolic complications and anti-coagulation is probably not justified.

Adult↗
PubMed1994

[The ventricular dysrhythmia profile in patients with mitral valve pathology].

OBJECTIVE: To study the relation between ventricular arrhythmias and echocardiographic left ventricular data, in patients with mitral valve pathology. DESIGN: Retrospective study, based on Holter department data on ventricular arrhythmias. POPULATION: We studied 128 patients: 36 were male, 92 were female. Their mean age was 52 +/- 11 years. Three groups were outlined: 54 patients had mitral stenosis (ME), 15 patients had mitral disease (MD) and 59 had associated aortic pathology (MA). METHODS: Patients clinical records were reviewed according to an evaluating protocol. In each Holter recorded the number of premature ventricular contractions per hour (PVC/h), as well as the existence of complex ectopic forms (CF) was considered. Echocardiographic left ventricular data used was: diastolic diameter (DD), systolic diameter (DS) and shortening fraction (SF). Treatment was not significantly different between the three groups, when 24 hour monitoring was performed. RESULTS: We found the average number of PVC/h to be 14 +/- 45 in the ME group, 58 +/- 85 in the MD group and 52 +/- 11 in the MA group. There is significant difference between ME and either DM, or MA. In patients with ME significant relations were found between the occurrence of CF a greater DS (p < 0.01) and a lesser SF (p = 0.02). No significance was found for the occurrence of PVC. In patients diagnosed as DM, the occurrence of PVC/h (> or = 10) was related with greater DD (p = 0.01) or DS (p = 0.04), but there was no relation to SF. Finally in the MA group PVC occurrence was strongly related (p < 0.01) with all the echocardiographic values and thinner relations were found towards SF (p = 0.02 for DD, p = 0.03 for DS and p = 0.05 for SF). CONCLUSIONS: Ventricular arrhythmic occurrence is less frequent in ME. However, in the three groups, there is worsening left ventricular arrhythmic frequency in direct relation to greater ventricular dimensions, or compromised systolic function.

Adult↗
PubMed1994

[Superiority of the reinjection method compared with the redistribution of thallium-201 in the evaluation of reversibility after myocardial infarction].

OBJECTIVE: To assess the relative capacity of thallium-201 reinjection (RI) and redistribution (RD) for detection of reversibility in patients after myocardial infarction. DESIGN: We prospectively studied patients referred to myocardial scintigraphy for viability evaluation with stress, redistribution and reinjection images. METHODS: Patients were studied with thallium-201 SPECT using three imaging acquisitions--stress, redistribution three to four hours later and reinjection 30-60 minutes after a second injection of thallium under nitroglycerin effect. Thallium uptake was classified in a 0 to 4 intensity scale in each of 13 myocardial segments and a score obtained. Reversibility was classified as "definite" if the increase in thallium uptake was > or = 2 in a myocardial segment and as "possible" if the increase was one. PATIENTS: We studied 44 patients with previous myocardial infarction. RESULTS: The perfusion score after stress was 37.3 +/- 6.0, improving to 39.8 +/- 6.7 after redistribution and to 43.6 +/- 7.6 after reinjection (p < 0.02 between RD and RI). RD identified reversibility in 38% and RI in 63% (p < 0.001) of the 232 segments with perfusion defects. RI showed reversibility in 39% (definite in 25% and possible in 14%) of the 137 fixed perfusion defects in RD. For the detection of reversibility RI was superior to RD in all sub-groups analyzed. We found a relationship the degree of collateral circulation in the infarct related artery and the amount of reversibility in the infarcted area. CONCLUSIONS: These data suggest a clear superiority of reinjection over redistribution in thallium-201 scintigraphy for the detection of reversibility of perfusion defects after myocardial infarction, and must probably be considered as a routine procedure for myocardial viability assessment.

Adult↗
PubMed1994

[Evaluation of myocardial reserve as a contribution to the surgical indication in aortic insufficiency].

Surgical indication in symptomatic patients with chronic aortic regurgitation is mandatory, but it is sometimes doubtful in two extreme situations: asymptomatic patients and patients with severe left ventricular dysfunction. The authors review the contribution of radionuclide angiography (RNA) for the selection of surgical indication in these two groups of patients, by the evaluation of baseline ejection fraction and of contractile reserve, defined as ejection fraction variation with exercise in asymptomatic patients and with inotropic stimulation in patients with severe left ventricular dysfunction. In asymptomatic patients, RNA may contribute to the selection of patients with incipient ventricular dysfunction (manifested only with exercise), in which a closer follow-up should be obtained, to propose surgery early when baseline ventricular dysfunction appears. In patients with severe ventricular dysfunction, RNA may give us some clues on the probability of left ventricular function recovery after surgery, contribution to the decision of proposing conventional surgery or heart transplant. The authors shortly review preliminary data on the follow-up of 48 patients with chronic aortic regurgitation, studied by RNA with exercise (44 patients) or dobutamine infusion (4 patients) at the Hospital de Santa Cruz from 1987 to 1991. Fifteen of these patients have been submitted to surgery.

Aortic Valve Insufficiency↗