1,721,152 research outputs found
Correlazione tra incidenza di aritmie cardiache e dati emogasometrici in soggetti affetti da insufficienza respiratoria
No full textAsymptomatic aortic dissection associated with a mitral prosthetic leak: a clinical case report
No full textA case of aortic dissection ("DeBakey type III") in an asymptomatic 78-year-old woman is described. The patient underwent a mitral valve replacement (bioprosthesis Sorin) in June 1990 for severe mitral stenosis; in October 1990 she was admitted to our hospital for severe dyspnea and cardiac failure with good response to medical treatment. The routine echo color Doppler examination showed only a hint of paraprosthetic leak, which required further investigation by transesophageal echocardiography. This approach revealed the presence of a regurgitant jet extending from the prosthetic mitral valve toward the atrial septum. The examination of the thoracic aorta revealed the presence of a dissection flap; the color Doppler technique showed a bidirectional flow through the site of communication between the two lumina. The extension of the dissection from the aortic arch to the origin of the renal branches was confirmed by computerized axial tomography. We emphasize the importance of the transesophageal approach in elderly patients with aortic dissection, often asymptomati
A case of subannular aortic aneurysm detected by transoesophageal echocardiography
No full textSubvalvular aortic aneurysm is a cardiac abnormality extremely uncommon in white adult patients. Accurate diagnosis can be made by transoesophageal echocardiography which is the modality of choice for non-invasive recognition of aortic and subaortic abnormalities. In this report we describe, in a 47-year-old white man with subvalvular aortic aneurysm associated to aortic bicuspid valve, the echocardiographic diagnosis and cardiac intervention of aortic valve replacement with surgical obliteration of the orifice. A good surgical result was confirmed by an echocardiographic transthoracic examination performed after 6 month
Frequency of disorders of cardiac rhythm during respiratory insufficiency and their relation to the blood gas analytical picture
No full textSpeckle tracking echocardiography for detection of subclinical cardiac involvement in rheumatoid arthritis
No full textPrognostic value of different left ventricular filling patterns assessed by automated border detection technique in patients with dilated cardiomyopathy
No full textPatients with dilated cardiomyopathy (DCM) often require invasive evaluation of left ventricular diastolic function. Using automated border detection (ABD) technique we calculated left ventricular diastolic parameters such as peak filling rate (PFR), peak atrial filling rate (PAFR), both normalized for end-diastolic volume, PFR/PAFR ratio, and time to PFR. We also compared derivative ABD indexes with transmitral Doppler flow parameters (peak of E wave, peak of A wave and E/A ratio) in patients with different degrees of diastolic dysfunction. Furthermore, we studied 30 ambulatory DCM patients (21 males, 9 females, mean age 62 ± 9 years, ejection fraction 27 ± 11%), all in sinus rhythm, and 12 age-matched normal subjects using ABD technique. DCM patients did not differ from normal subjects by E/A (2 ± 2.6 vs 0.98 ± 0.3) and PFR/PAFR ratios (2.0 ± 1.4 vs 1.3 ± 0.3). A significant correlation was found between E/A and PFR/PAFR ratios (r = 0.81, p < 0.001). Subdividing DCM patients according to transmitral filling patterns (abnormal relaxation, pseudonormalized, and restrictive) we found in DCM patients with severe diastolic dysfunction a significantly decreased PAFR and time to PFR with an increased PFR/PAFR ratio. In conclusion, a) ABD-derived parameters of left ventricular function provide a simple and reliable method for the evaluation of diastolic dysfunction in DCM patients; b) PFR/PAFR ratio is able to differentiate DCM patients with pseudonormalized left ventricular filling pattern; c) this method may be used in different clinical conditions for serial evaluation of left ventricular performance
Hemodynamic response to somatostatin at rest and during sympathetic activation in idiopathic orthostatic hypotension
No full textIdiopathic orthostatic hypotension (IOH) represents a degenerative disorder of the peripheral nervous system characterized by low values of arterial blood pressure during orthostatism, with reduction in serum catecholamines. Since treatment of symptomatic IOH has been unsatisfactory till now, we studied the hemodynamic response to somatostatin (S) (Octreotide, 100 micrograms sc) at rest (R) and during sympathetic activation (tilting, T) by means of 2D and/or color Doppler echocardiography, in 5 ambulatory IOH patients (4M, 1F; aged 65 +/- 5 years), with simultaneous recording of blood pressure and heart rate. Post-S, an increased blood pressure was evident during T without heart rate modifications (pre- vs post-S, SAP: 92 +/- 9 vs 148 +/- 12; DAP: 61 +/- 4 vs 90 +/- 9 mmHg; p less than 0.05), while systolic echo parameters did not change significantly. Doppler aortic velocity curve showed during T a reduction of Vmax (pre- vs post-S: 0.98 +/- 0.09 vs 0.73 +/- 0.03 m/s; p less than 0.05) and of cardiac output, due to unchanged preload. Pre-S, at rest, Doppler mitral velocity curve presented a normal E/A ratio as in normal subjects, with a reduced E peak and an increased A peak post-S, indirect signs of increased afterload. Pre-S, E and A peak velocities underwent progressive decrease during T, markedly more evident post-S. Total peripheral resistance, at rest and during T, increased post-S too (pre- vs post-S, rest: 2406 +/- 267 vs 3162 +/- 599; T: 1634 +/- 201 vs 2784 +/- 425 dyne*s/cm-5; p less than 0.05
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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