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J Zamorano

Publications and source records attributed to J Zamorano.

At least 73 records · Page 4Linked to original sources
PubMed1994

[Evaluation of coronary revascularization: comparison between perfusion with dipyridamole Tc99m sestaMIBI and amrinone-echocardiography as predictors of viability].

We studied left ventricular perfusion and motility in 37 patients with coronary artery disease and disturbances of parietal motility, aged 57 +/- 9 years old, before and after revascularization. Perfusion was assessed with dipyridamole-tc99m MIBI SPECT and motility was assessed with two dimensional echocardiography with amrinone. Myocardial segments were defined as normal, viable or necrotic in both studies. Eighteen subjects were subjected to angioplasty and 19 to coronary bypass surgery. Submitted SPECT and echocardiography were repeated 64 +/- 15 and 69 +/- 23 days after revascularization respectively. The concordance between SPECT and echocardiographic pre-revascularization diagnosis was 60.1% Eighty one percent of segments considered viable with SPECT and 71% thus considered with echocardiography improved after revascularization. Likewise, 50% of segments considered necrotic with SPECT and 68% of segment thus considered with echocardiography did not improve. It is concluded that although there is a good concordance between both methods, they have limitations on the study of myocardial viability and should be considered as second choice.

Adult↗
PubMed1994

[Tomographic myocardial perfusion (SPECT) using 99mTc sestamibi-dipyridamole and 2-d-echocardiography with amrinone pre and post myocardial revascularization in 2 cases].

We report two male patients aged 50 and 55 years old with coronary artery disease who were treated with surgical revascularization and angioplasty respectively. To assess viable and ischemic myocardial territories, they were studied before and after revascularization with radionuclide perfusion SPECT with Tc99m-Sestamibi under Dipyridamole and with 2-D echocardiography at baseline and after the use of amrinone. Improvement in relative perfusion on SPECT and wall motion on 2-D echocardiography indicated tissue recovery.

Amrinone↗
PubMed1994

[Contribution of transesophageal echocardiography in the assessment of cardiac myxomas].

INTRODUCTION AND OBJECTIVES: Transthoracic echocardiography is the gold-standard method in the diagnosis of cardiac myxomas. Our aim was to analyze the usefulness of transesophageal echocardiography in the diagnosis and assessment of patients with cardiac myxomas. PATIENTS AND METHODS: From 1990 to 1992, 14 patients underwent cardiac surgery with the echocardiographic diagnosis (transthoracic and/or transesophageal approach) of cardiac myxomas. Thirteen (86%) of the 14 patients had after surgery histological confirmation of myxoma. Of the 13 myxomas, 10 were located in the left atrium and 3 in the right atrium. RESULTS: Transthoracic echocardiography was able to diagnose the presence of myxoma in 12 of the 13 patients, whereas the transesophageal approach detected all of them. The precise attaching point of the tumour was seen in 9 patients with transthoracic echocardiography and in all the patients with the transesophageal approach. Also the presence of satellite tumours seen in 2 patients was only detected by transesophageal echocardiography. CONCLUSION: We conclude that the sensitivity in the diagnosis of cardiac myxomas is similar with both techniques, but transesophageal echocardiography is much more accurate in the detection of the precise attaching point and the presence of satellite tumours. We think that TEE is a useful tool, complementary to TTE, in the assessment of patients with cardiac myxomas before going to surgery.

Echocardiography, Transesophageal↗
PubMed1993

Percutaneous mitral valvuloplasty with severe pulmonary artery hypertension.

The aim of this study was to assess the initial and midterm outcome of patients with severe pulmonary hypertension undergoing percutaneous mitral valvuloplasty (PMV). Accordingly, the baseline characteristics, immediate results and follow-up of 64 consecutive patients with severe pulmonary artery hypertension (systolic pulmonary artery pressure > or = 60 mm Hg on cardiac catheterization) (group I) were analyzed and compared with those of 194 consecutive patients with lower pulmonary pressures (group II). Patients in group I were more symptomatic (New York Heart Association functional class > or = III, 72 vs 40%, p < 0.001) and had higher echocardiographic scores (8.6 +/- 2 vs 7.4 +/- 1, p < 0.05). Before PMV, mitral gradient was higher (17 +/- 6 vs 13 +/- 5 mm Hg, p < 0.025) and mitral valve area smaller (0.79 +/- 0.2 vs 0.96 +/- 0.2 cm2, p < 0.005) in group I patients, who also had higher pulmonary vascular resistances (469 +/- 299 vs 157 +/- 125 dynes s-1 cm-5, p < 0.005). On multivariate analysis patients in group I were more symptomatic, had smaller mitral valve areas and higher mitral gradients. PMV success (area gain > 50% without complications) was similar (89 vs 87%) in both groups. After PMV final mitral gradient (5 +/- 2 vs 4 +/- 2 mm Hg) and area (1.82 +/- 0.5 vs 1.87 +/- 0.5 cm2) were similar in both groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Differential expression of IL-4 receptors in human T and B lymphocytes.

IL-4R have been described in unstimulated human T and B lymphocytes. However, a precise comparative study on the expression and regulation of IL-4R in isolated human T and B cell populations has not yet been fully assessed. We examined the mRNA levels and the cell membrane expression of IL-4R in freshly isolated T and B lymphocytes as well as in in vivo- and in vitro-stimulated cells. IL-4R protein expression and transcript levels were higher in tonsillar unstimulated B cells than in T cells. Splenic and peripheral blood B lymphocytes also expressed higher surface IL-4R in their membranes than T cells did. Large B lymphocytes from tonsils (in vivo-activated cells) obtained by Percoll gradient centrifugation displayed higher IL-4R levels than resting cells. On activation in vitro of T lymphocytes with IL-2 or PHA, slight increments on the IL-4R mRNA and protein levels were achieved. However, maximal levels of IL-4R expression were obtained on T cell incubation with IL-4 at a concentration of 100 U/ml. Similarly, the same concentration of this lymphokine up-regulated the surface IL-4R molecules and the IL-4R mRNA levels in purified B lymphocytes. Cross-linkage of surface Ig by insolubilized anti-IgM potentiated the effect of IL-4 in up-regulating IL-4R expression in B cells, probably by inducing outgrowth of IL-4R positive subpopulations. The B cell mitogen, Staphylococcus Aureus Cowan I, although inducing cell proliferation, was ineffective in promoting new receptor synthesis. Cell proliferation was not required for IL-4-dependent IL-4R up-regulation on both T and B lymphocytes.

Adult↗
PubMed1993

Right atrial diverticulum and hypertrophic cardiomyopathy.

This report describes the case of a young man with a right atrial diverticulum and hypertrophic cardiomyopathy who died suddenly. The relationship of congenital diverticulosis of the heart with hypertrophic cardiomyopathy is discussed.

Adolescent↗
PubMed1993

Diagnosis of mitral valve myxoma by transesophageal echocardiography.

Mitral valve myxomas are rare. We report a patient with a mitral myxoma arising from the posterior mitral leaflet in whom transthoracic echocardiography revealed equivocal findings. However, transoesophageal echocardiography provided accurate relevant anatomical information including the size, morphological characteristics, and tumour attachment point.

Echocardiography↗
PubMed1993

Coronary artery remodeling in atherosclerotic disease: an intravascular ultrasonic study in vivo.

BACKGROUND: Pathologic studies have revealed that coronary arteries undergo compensatory enlargement in the presence of atherosclerosis. METHODS: In order to assess coronary artery remodeling in vivo, we used intravascular ultrasound to examine 46 patients (36 men and 10 women; aged 58.2 +/- 6.8 years) with non-calcified plaques. The vessel, lumen, and plaque areas of the atherosclerotic and of normal proximal and distal segments were determined. RESULTS: A total of 92 atherosclerotic segments were analyzed. The degree of stenosis ranged from 9.2 to 92.8% (mean 34.1 +/- 16.9%) and the plaque area from 2 to 19.6 mm2 (mean 6.3 +/- 3.6 mm2). The vessel area of the atherosclerotic segment (mean 20.4 +/- 7.3 mm2) was larger than that of the proximal segment (mean 18.7 +/- 7.3 mm2, P = 0.018). The vessel area increased in proportion to plaque area. This relationship can be described using the equation y = 23.5(1-e-0.35x). The difference between the vessel area in the atherosclerotic segment and that in the proximal normal segment correlated with the percentage of stenosis (r = 0.53, P < 0.005) until the degree of stenosis exceeded 45%. CONCLUSION: This study indicates that coronary artery remodeling, previously observed in pathologic studies, can be evaluated using intravascular ultrasound in vivo. As a result of the compensatory enlargement of the vessel, coronary angiography cannot be used to detect or exclude the early signs of coronary atherosclerosis.

Adult↗
PubMed1993

[Transthoracic and transesophageal echocardiography in the pre- and postoperative assessment of interatrial communication].

BACKGROUND AND OBJECTIVES: Transthoracic echocardiography is the most useful noninvasive method to diagnose atrial septal defect. It is suggested by some authors that transesophageal echocardiography is more accurate than transthoracic echocardiography in this setting. Our aim was to compare the usefulness of both techniques in: 1) diagnosing atrial septal defect, 2) detecting associated anomalies and 3) postoperative assessment. PATIENTS AND METHODS: Pre and postoperative transthoracic and transesophageal echocardiography were performed in 27 patients in whom diagnosis of atrial septal defect was confirmed at surgery. RESULTS: Transthoracic echocardiography demonstrated the defect in 20 patients (74%) (8 ostium primum, 10 ostium secundum and 2 sinus venosus). The 27 patients (100%) were correctly diagnosed by transesophageal echocardiography (8 ostium primum, 12 ostium secundum and 7 sinus venosus). Defect size determined by transthoracic echocardiography had a poor correlation with the surgical measurement (r = 0.34). A good correlation was obtained when transesophageal versus surgical defect size measurements were compared (r = 0.85; p < 0.05). Transesophageal echocardiography was superior in detecting associated anomalies (5 patients with anomalous partial pulmonary venous drainage, 3 persistence of left superior vena cava and 1 atrial septal aneurysm). Moreover, this technique better determined residual atrial septal defect, and detected a postsurgical inferior vena cava connection to the left atrium. CONCLUSIONS: Transesophageal echocardiography is superior to transthoracic echocardiography in diagnosing atrial septal defect sinus venosus type, detecting associated anomalies and postoperative assessment. Transthoracic echocardiography is diagnostic in the majority of patients with atrial septal defect ostium primum and ostium secundum types.

Adolescent↗
PubMed1993

[Papillary muscle rupture. Diagnosis with transesophageal echocardiography].

Two patients with acute myocardial infarction and papillary muscle rupture are presented. The diagnosis of papillary muscle rupture was made by transesophageal echocardiography. The transesophageal echocardiographic findings and the usefulness of this technique in the diagnosis of papillary muscle rupture are described.

Adult↗
PubMed1992

Comparison of results of percutaneous mitral valvuloplasty in patients with large (greater than 6 cm) versus those with smaller left atria.

To determine whether the presence of an aneurysmatic (severely enlarged) left atrium (greater than 60 mm on echocardiography) influences results of percutaneous mitral valvuloplasty (PMV), the clinical, echocardiographic and hemodynamic characteristics and the results of this technique were compared in 46 consecutive patients with aneurysmatic left atrium (group I) and 125 consecutive patients without such echocardiographic finding (group II). Left atrial size was 70.5 +/- 8 vs 50.1 +/- 6 mm (p less than 0.005) in groups I and II, respectively. Patients in group I were older (57 +/- 12 vs 48 +/- 12 years, p less than 0.025), more symptomatic (New York Heart Association functional class greater than or equal to III or IV: 67 vs 42%, p less than 0.05), and had atrial fibrillation more frequently (91 vs 44%, p less than 0.001). The echocardiographic score (8.9 +/- 1.9 vs 7.5 +/- 2, p less than 0.005) and the incidence of mild mitral regurgitation on angiography before PMV (54 vs 30%, p less than 0.01) was also higher in group I patients. Hemodynamic parameters before PMV were similar in both groups, but after the procedure, final mitral valve area (1.61 +/- 0.5 vs 1.95 +/- 0.4 cm2, p less than 0.05) and the absolute increase in mitral area (0.81 +/- 0.3 vs 1.02 +/- 0.3 cm2, p less than 0.05) were lower and mean pulmonary artery pressure (35 +/- 10 vs 28 +/- 9 mm Hg, p less than 0.025) was higher in group I.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Nuclear magnetic resonance spectroscopy of excised human hearts.

BACKGROUND: Phosphorus nuclear magnetic resonance spectroscopy has been proposed as a method of studying the metabolism of the myocardium in patients. Little is known about 31P nuclear magnetic resonance spectroscopy of diseased human hearts. METHODS: Two donor hearts meeting the requirements for heart transplantation and 11 diseased hearts were removed during a transplantation procedure and were studied in a horizontal 2.35 T superconducting magnet. Spectra were obtained at 0 degrees C about 30 minutes after the excision. The areas of the inorganic phosphate peak (Pi) and of the phosphocreatine peak (PCr) were summed and expressed as a ratio with respect to the area of the beta ATP peak. RESULTS: The ratio (Pi + PCr)/beta ATP was found to be significantly lower in five hearts with a myocardial infarct (0.77 (0.18)) than in hearts with dilated cardiomyopathy (1.25 (0.29)) and in normal hearts (1.69 (0.11)). The area of the phosphodiester peak was expressed as a ratio with respect to the area of the beta ATP peak: no differences were found between the three groups. CONCLUSIONS: These results suggest that the phosphocreatine concentration is lower in ischaemic heart disease than in dilated cardiomyopathy and that the phosphodiester peak is probably not useful in distinguishing between these two types of heart disease.

Adenosine Triphosphate↗
PubMed1992

[The usefulness of intravascular echography during the percutaneous dilatation of aortic coarctation].

An intravascular ultrasound study was performed in a patient, to assess the anatomy of aortic coarctation and the results obtained after percutaneous dilation with a balloon catheter. Intravascular ultrasound imaging provides important additional information, not obtainable with other diagnostic procedures, regarding aortic wall structure and thickness. After balloon dilation, aortic disruption was clearly observed, accounting, together with the stretching of the outer layers of the aortic wall, for the increase in aortic luminal area. Intravascular ultrasound permitted also the accurate assessment of the improvement obtained. Intravascular imaging was clearly superior not only to conventional angiography, but also to transesophageal echocardiography in detecting the mechanism of dilation. We conclude that ultravascular ultrasound, with the additional information that it provides, may help in the selection of patients for percutaneous dilation of the coarctation as well as contributing to the identification of the mechanism of dilation.

Aorta, Thoracic↗
PubMed1992

[Intravascular ultrasound in patients with suspected aortic dissection: comparison with transesophageal echocardiography].

Thirteen patients with suspected aortic dissection (two women, 11 men, age 61 +/- 10.8 years) underwent transesophageal echocardiography (TEE), intravascular ultrasound (IVUS), angiography, and in part computed tomography (CT). TEE was performed using 3.5 or 3.75 MHz ultrasound transducers. IVUS examination was done using a 6F 20 MHz "rotational-tip" IVUS catheter (Boston Scientific) advanced over a guiding-wire positioned in the ascending aorta by the "side-saddle" technique. In two patients it was not possible to advance the catheter into the abdominal aorta. Of the remaining 11 patients, eight had aortic dissection (six Typ III, one Typ II, and one Typ I, de Bakey classification). Two patients had aortic aneurysms without dissection and one patient had a perforation of the ascending aorta. TEE, CT, and angiography led to the correct diagnosis in all patients, while IVUS failed to provide precise information within the ascending aorta and the aortic arch. Reasons were the limited scanfield of the 20 MHz transducer and the inability to steer and position the IVUS catheter. Contrary to the limited value in the ascending aorta, IVUS could successfully scan the entire descending aorta, including the dissection membrane and the originating vessels, if the max. diameter was less than 4 cm. No adverse effects occurred. Intravascular ultrasound allows to scan the entire aorta in patients with suspected aortic dissection. The current limitations can be solved only by the introduction of steerable and/or low frequency catheters.

Aged↗
PubMed1992

[The evaluation of the results after coronary angioplasty by intracoronary Doppler and quantitative angiography. The correlation of both methods].

To study the importance of measuring coronary flow reserve immediately after coronary angioplasty we have analysed the results obtained after 28 angioplasties performed in 21 patients. Coronary flow reserve was measured with a 3F intracoronary catheter selectively placed in the dilated artery. Corresponding coronary angiography was analysed with an automatic edge detection program (ARTREK) and visual estimation. Coronary flow reserve increased in 26/27 cases after angioplasty from 2.4 +/- 1.3 to 4.1 +/- 2.7 (p less than 0.001). A correlation was found between minimal luminal area and minimal luminal diameter after coronary angioplasty, and coronary flow reserve (r = 0.46; p less than 0.05 and r = 0.47; p less than 0.05, respectively). The finding of a normal coronary flow reserve (greater than or equal to 3.5), had a 100% specificity but only 56% sensitivity to detect angiographic success (residual stenosis less than 50%). However 47% of patients with angiographic success did not reach normal values of coronary flow reserve. Visual estimation of the stenosis had a good correlation with automatic evaluation but significant scattering was observed at visual levels less than or equal to 25%. Visual assessment underestimated residual stenosis in all but one of the procedures. We conclude that coronary flow reserve is a potentially useful index for assessing the results after angioplasty that may complement coronary angiography. Nonetheless substantial differences between both methods exist in a significant number of cases. The relative merits of both methods, as well as the particular circumstances in which coronary flow reserve should be used, require further studies.

Angioplasty, Balloon, Coronary↗