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P Zarco

Publications and source records attributed to P Zarco.

At least 19 recordsLinked to original sources
PubMed2003

Aortic stenosis.

Explore the source record for details and available documents.

Aged↗
PubMed1997

Retrograde atrial kick in acute aortic regurgitation. Study of mitral and pulmonary venous flow velocities by transthoracic and transesophageal echocardiography.

BACKGROUND AND HYPOTHESIS: The purpose of this study was the comprehensive evaluation of the changes in pulmonary venous and mitral flow velocities of patients with acute and chronic severe aortic regurgitation. Transmitral flow velocities obtained with pulsed-wave Doppler echocardiography have been used to provide information on left ventricular (LV) filling and diastolic function. Pulmonary venous flow tracings are an important adjunct to LV inflow pattern in assessing LV diastolic function. METHODS: Fourteen patients with severe aortic regurgitation (8 chronic and 6 acute) and in sinus rhythm were examined by transthoracic and transesophageal pulsed Doppler echocardiography. Mitral and pulmonary flow velocities were recorded and compared. All patients had ejection fractions > 40%. RESULTS: Early mitral flow peak velocity was higher in patients with acute regurgitation (p < 0.001). The mitral A wave was absent in five patients with acute regurgitation. In contrast, a prominent reverse atrial pulmonary systolic wave AR was demonstrated in these patients. Peak diastolic velocity of the pulmonary venous flow was greater in patients with acute aortic regurgitation (0.76 +/- 0.13) than in patients with chronic aortic regurgitation (0.40 +/- 0.09) (p < 0.001). Peak systolic velocity did not differ significantly between the two groups. The systolic fraction of pulmonary venous flow in patients with acute aortic regurgitation was lower (0.43 +/- 0.05) than that of patients with chronic regurgitation (0.63 +/- 0.1) (p < 0.01). All patients with acute aortic regurgitation had an S/D ratio < 1, while those with chronic regurgitation had an S/D > 1 (p < 0.001) and an E/A < 1. CONCLUSION: Patients with severe acute aortic regurgitation showed a retrograde atrial kick (absence of transmitral A wave with prominent pulmonary AR wave). These patients had an S/D ratio < 1 (restrictive Doppler pattern). Patients with chronic aortic regurgitation exhibited a Doppler pattern of abnormal LV relaxation (E/A < 1, S/D > 1).

Acute Disease↗
PubMed1996

[Morphological and quantitative analysis of the mechanism of balloon angioplasty. An intravascular ultrasonic study].

BACKGROUND AND OBJECTIVES: Intracoronary ultrasound allows to study in vivo the morphology of the arterial wall, the presence and composition of atheroma and the associated lumen encroachment. The objective of our study was to assess the value of intravascular ultrasound to determine the dilatation mechanism after a conventional balloon angioplasty. PATIENTS AND METHODS: Sixteen patients were examined with intravascular ultrasound before and after they had undergone percutaneous transluminal coronary angioplasty. A mechanical intravascular ultrasound system was used. Two different types of imaging catheters were used in this study: a 20 MHz, 4.8 F catheter in 5 patients and a 30 MHz, 3.5 F in 11 patients. RESULTS: Quantitative and qualitative assessments were made from the angiograms and the ultrasound images. Seven out of 16 patients had a calcified plaque, in 8 patients the plaque was fibrotic and in 1 patient soft. Rupture of the plaque was the most common dilatation pattern. Post-PTCA the cross-sectional arterial area was increased from 15.3 +/- 5.2 mm2 to 17.3 +/- 6.2 mm2, the intraluminal area was increased from 2.7 +/- 2.5 mm2 to 7.3 +/- 3.4 mm2, and the plaque area was reduced from 12.3 +/- 4.8 mm2 to 9.7 +/- 3.4 mm2. The quantitative analysis showed that the "most frequent dilatation mechanism" found was the reduction of size plaque, an increase in cross-sectional arterial area was present in only 4 patients (25%). The incidence of depth rupture of the plaque was greater in patients with a calcified plaque than in those without (NS). CONCLUSIONS: 1). Intracoronary ultrasound provides a complete description of plaque composition and geometry before and after coronary balloon angioplasty; 2) several morphologic dilatation patterns were found, and plaque tearing was the most common, and 3) increase in luminal area was most frequently due to a reduction in plaque area. Nevertheless an increase in the cross-sectional arterial area was also common, but less important.

Aged↗
PubMed1996

HLA-B27--associated uveitis presenting with diffuse vitritis.

A 26-year-old man complained of a sudden decrease in vision in the left eye. He had a past medical history of pauciarticular juvenile rheumatoid arthritis with a positive HLA-B27 haplotype and negative antinuclear antibodies and later development of ankylosing spondylitis. His ocular history was unremarkable. An ophthalmic examination revealed a predominant diffuse vitritis (3+) in the left eye. The uveitis improved after treatment with topical and systemic steroids. Following an extensive clinical and laboratory evaluation, a final diagnosis of HLA-B27-associated uveitis was made. Although uncommon, diffuse vitritis can occur in the setting of this uveitis and may be a predominant symptom.

Adult↗
PubMed1995

Angioscopic findings during coronary angioplasty of coronary occlusions.

OBJECTIVES: This study sought to elucidate angioscopic findings in totally occluded vessels before and after intervention. BACKGROUND: Coronary angioscopy allows direct visualization of the lumen surface of the coronary arteries; however, the utility of coronary angioscopy during coronary angioplasty of vessels with a total occlusion is unknown. METHODS: Twenty-one consecutive patients (mean [+/- SD] 58 +/- 9 years, range 39 to 77; 3 women, 18 men) undergoing dilation of an occluded vessel were studied with coronary angioscopy. Occlusions were classified as functional in 8 patients (Thrombolysis in Myocardial Infarction [TIMI] flow grade 1) and anatomic in 13 (TIMI flow grade 0). Once the guide wire had crossed the occlusion, coronary angioscopy was attempted before and after angioplasty. RESULTS: In all patients, coronary angioscopy before dilation visualized protruding material occluding the coronary lumen where the guide wire was wedged. The occlusion consisted of red thrombus in 19 patients (90%) (2 with isolated occlusive thrombus, 17 with thrombus associated with atherosclerotic plaque) and protruding yellow plaque in 2 patients (10%). However, on angiography only 7 occlusions (33%) had data consistent with thrombus (p < 0.01 vs. coronary angioscopy). Successful dilation was obtained in 20 patients. After dilation, coronary angioscopy was repeated in 18 patients, revealing residual thrombus with plaque in 16 (89%) and a residual yellow plaque in 2. In addition, coronary angioscopy revealed coronary dissections in 13 patients (72%); however, angiography revealed dissections only in 10 patients (55%) and residual thrombus in 2 (10%) (p < 0.001). In one patient, coronary angioscopy visualized silent distal embolization of a red thrombus not previously recognized on angiography. CONCLUSIONS: Before intervention, coronary angioscopy provides unique insights into the pathologic substrate of occluded coronary vessels. An occlusive plaque with thrombus is the most common underlying substrate in these lesions. After successful dilation, angiographically silent mural thrombus is seen in most patients. This information could be used to assist in the selection of candidates and type of coronary interventions and could also prove to be of prognostic value in patients with occluded vessels.

Angioplasty, Balloon, Coronary↗
PubMed1995

IL-1 beta and IL-6 stimulate the production of platelet-activating factor (PAF) by cultured rabbit synovial cells.

The aim of this study was to determine whether synovial cells are capable of producing PAF in the presence of cytokines such as IL-1 beta and IL-6 and other stimuli. Synovial cells were obtained from joints of healthy rabbits. PAF production was assayed by measurement of serotonin release in rabbit platelets and the incorporation of 3H-acetate into PAF. Synovial cells produced PAF after 5 min of incubation with ionophore A23187, reaching the maximal amount at 15 min (4.3 +/- 0.7 x 10(-3) pmol of PAF/mg protein, P < 0.005, n = 4), and declining afterwards. The treatment of synoviocytes with IL-1 beta and IL-6 induced synthesis of PAF after 5 min of stimulation, reaching the greatest production at 15 min with IL-6 and 30 min with IL-1 beta (3.6 +/- 1.1 x 10(-3) and 3.3 +/- 1.2 pmol of PAF/mg protein, respectively, P < 0.05, n = 4). The incubation of the cells with PMSF, an inhibitor of acetylhydrolase, before the addition of the stimuli, increased the incorporation rate of 3H-acetate, suggesting a rapid degradation of PAF by synoviocytes. These results demonstrate that synovial cells can produce PAF after stimulation with agonists, such as ionophore, and cytokines. Thus, PAF, acting alone or with other mediators, could amplify the inflammatory joint reaction.

Animals↗
PubMed1995

[Myocardial diseases: lessons from the past and future prospects].

This report provides an overview of current concepts on the cardiomyopathies. They constitute a heterogeneous group of diseases with complex interrelations between clinical manifestations, pathophysiology and therapy. Special emphasis was made to review new advances on the diagnosis and current management of patients with hypertrophic cardiomyopathy. The link between the classical knowledge and recent--still evolving--ideas is addressed to provide the--state of the art--concerning the implications on the clinical decision making process. Controversial issues such as diagnostic criteria, prognostic features and implications of electrocardiographic and echocardiographic data are revisited in brief. Data suggesting the value of dual chamber pacing as a means to relieve outflow tract obstruction and to improve symptoms in patients with hypertrophic cardiomyopathy are discussed. The molecular basis of this entity together with the characterization of the responsible genetic mutations are reviewed in detail.

Adolescent↗
PubMed1994

Determinants of coronary compliance in patients with coronary artery disease: an intravascular ultrasound study.

OBJECTIVES: The aim of this study was to elucidate determinants of coronary compliance in patients with coronary artery disease. BACKGROUND: Intravascular ultrasound potentially enables in vivo evaluation of coronary artery compliance. METHODS: Twenty-seven patients (mean age [+/- SD] 57 +/- 11 years, three women) undergoing coronary angioplasty were studied with intravascular ultrasound imaging. A mechanical intravascular ultrasound system (4.8F, 20 MHz) was used. A total of 58 different coronary segments (proximal to the target angiographic lesion) were studied. Of these, 35 were located in the left anterior descending, 9 in the left main, 8 in the left circumflex and 6 in the right coronary arteries. During intravascular ultrasound imaging, 22 segments (38%) appeared normal, but 36 (62%) had plaque (24 fibrotic, 3 lipidic and 9 calcified). Systolic-diastolic changes in area (delta A) and pressure (delta P) with respect to vessel area (A) were used to study normalized compliance (Normalized compliance = [delta A/A]/delta P [mm Hg-1 x 10(3)]). RESULTS: Lumen area and plaque area were 12.6 +/- 5.7 and 3 +/- 3 min2, respectively. Plaque was concentric (more than two quadrants) at 10 sites, but the remaining 26 plaques were eccentric. Compliance was inversely related to age (r = -0.34, p < 0.05) but was not related to other clinical variables. Compliance was greater in the left main coronary artery (3.9 +/- 2.1 vs. 1.8 +/- 1.2 mm Hg-1, p < 0.05) and in coronary segments with normal findings on ultrasound imaging (2.9 +/- 1.9 vs. 1.6 +/- 1.1 mm Hg-1, p < 0.01). Moreover, at diseased coronary segments compliance was lower in calcified plaques than in other types of plaques (1.2 +/- 0.7 vs. 2.3 +/- 1.6 mm Hg-1, p < 0.01) but was similar in concentric and eccentric plaques (1.6 +/- 1.5 vs. 1.6 +/- 0.9 mm Hg-1). Plaque area (r = -0.38, p < 0.01) was inversely correlated with compliance. On multivariate analysis, only age and plaque area were independently related to compliance. CONCLUSIONS: Intravascular ultrasound may be used to evaluate compliance in patients with coronary artery disease. Compliance is reduced with increasing age and is mainly determined by the arterial site and by the presence, size and characteristics of plaque on intravascular ultrasound imaging.

Age Factors↗
PubMed1994

Early angiographic changes of side branches arising from a Palmaz-Schatz stented coronary segment: results and clinical implications.

OBJECTIVES: The purpose of this study was to assess the effects and clinical implications of Palmaz-Schatz stent implantation on coronary blood flow in side branches arising from a stented coronary artery segment. BACKGROUND: The occlusion of a side branch is a well defined risk after balloon angioplasty. However, the impact of stenting on the coronary flow in side branches arising within the stented segment is unknown. METHODS: Forty-six stented coronary artery segments with 79 side branches emerging from the stented segment were analyzed. Angiographic studies were performed before angioplasty, after balloon dilation, immediately after stenting and 24 h later. Side branches were classified as follows: type A (> or = 1 mm in diameter, with ostial narrowing), type B (> or = 1 mm in diameter, without ostial narrowing), type C (< 1 mm in diameter, with ostial narrowing) and type D (< 1 mm in diameter, without ostial narrowing). Quantitative angiography was used to assess the diameter of the side branches. RESULTS: Stents were implanted electively in lesions with restenosis (41 stents, 89%) or with a suboptimal result after angioplasty (5 stents, 11%). Nine side branches (11%) were type A, 25 (32%) type B, 7 (9%) type C and 38 (48%) type D. At baseline, 68 side branches had Thrombolysis in Myocardial Infarction (TIMI) trial flow grade 3; 10 had grade 2; and 1 had grade 1. Flow worsened (TIMI grade > or = 1) in six side branches (8%) after balloon dilation and in four side branches (5%) after stenting. One additional side branch (1%) was occluded at 24 h. Of the 34 side branches > or = 1 mm in diameter (mean diameter 1.5 +/- 0.3 mm), 2 (6%) had flow impairment after stenting. Three patients experienced transient angina, but no acute myocardial infarction occurred as a result of a side branch occlusion. CONCLUSIONS: Coronary artery stenting does not modify anterograde flow in 90% of side branches. Coronary flow is reduced after stenting in a few branches, but this does not appear to have major clinical relevance.

Angioplasty, Balloon, Coronary↗