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Left Superior (leave + superior)

Distribution by Scientific Domains
Medical Sciences83%

Terms modified by Left Superior

  • leave superior pulmonary vein
    		•

    Selected Abstracts

    Electrical Connection Between Left Superior and Inferior Pulmonary Veins in a Patient with Paroxysmal Atrial Fibrillation

    JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 5 2002
    YOSHIHIDE TAKAHASHI M.D.
    Electrical Connection Between Pulmonary Veins. We report the case of a patient with paroxysmal atrial fibrillation, who underwent pulmonary vein (PV) electrical isolation from the left atrium (LA). Prior to achieving isolation of the left superior PV (LSPV) from the LA, earlier PV potentials were recorded inside the left inferior PV (LIPV) than LA activity during pacing at the distal LSPV. The LSPV finally was isolated by radiofrequency applications at the ostium of the LIPV. The patient had electrical connection between the LSPV and LIPV, and required radiofrequency ablation of the breakthroughs from the LA to LIPV for complete isolation of the LSPV. [source]

    Persistence of Left Supracardinal Vein in an Adult Patient with Heart,Hand Syndrome and Cardiac Pacemaker

    CONGENITAL HEART DISEASE, Issue 3 2008
    Jan Nemec MD
    ABSTRACT A patient with a sporadic heart,hand syndrome, which includes thumb hypoplasia, septum primum atrial septal defect, and cleft mitral valve is described. During attempted placement of a pacemaker lead, persistence of left superior and inferior vena cava was found in addition to the right-sided caval veins. This corresponds to persistence of left-sided supracardinal vein present during fetal development. [source]

    A comparison of brain activation patterns during covert and overt paced auditory serial addition test tasks

    HUMAN BRAIN MAPPING, Issue 6 2008
    Cristina Forn
    Abstract The Paced Auditory Serial Addition test (PASAT) is a sensitive task for evaluating cognitive impairment in patients with diffuse brain disorders, such as multiple sclerosis patients. Brain areas involved in this task have been investigated in diverse fMRI studies using different methodologies to control the subjects' responses during scanning. Here, we examined the possible differences between overt and covert responses during the PASAT task in 13 volunteers. Results showed similar activations in parietal and frontal brain areas during both versions of the task. The contrast between the two conditions (overt and covert) indicated that differences in these two methodologies were minimal. Unlike the covert condition, the overt version of the task obtained significant activations in the left superior and inferior frontal gyrus, bilateral occipital cortex, caudate nucleus and cerebellum. As expected, no significant overactivations were observed in the covert when compared with the overt condition. Discussion focuses on the lower cost of using verbal responses to monitor performance during the PASAT task, which might be generalisable to other frontal lobe tasks requiring discrete responses. Hum Brain Mapp, 2008. © 2007 Wiley-Liss, Inc. [source]

    Randomized Comparison of Bipolar versus Unipolar Plus Bipolar Recordings During Segmental Ostial Ablation of Pulmonary Veins

    JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 9 2002
    HIROSHI TADA M.D.
    Unipolar vs Bipolar Electrograms.Introduction: Segmental ostial ablation to isolate pulmonary veins is guided by pulmonary vein potentials. The aim of this prospective randomized study was to compare the utility of unipolar plus bipolar electrograms versus only bipolar electrograms as a guide for segmental ablation to isolate the pulmonary veins in patients with atrial fibrillation. Methods and Results: Isolation of the left superior, right superior, and left inferior pulmonary veins was attempted in 44 patients (35 men and 9 women; mean age 54 ± 10 years) with paroxysmal atrial fibrillation. A decapolar Lasso catheter was positioned in the pulmonary veins, near the ostium, and a conventional ablation catheter was used for segmental ablation aimed at elimination of all pulmonary vein potentials. One hundred fourteen pulmonary veins were randomly assigned for ostial ablation guided by either bipolar or unipolar plus bipolar recordings. Electrical isolation was achieved in 51 (96%) of 53 pulmonary veins randomized to the bipolar approach, and 57 (93%) of 61 pulmonary veins randomized to the unipolar plus bipolar approach (P = 0.7). In the unipolar plus bipolar group, the total duration of radiofrequency energy needed to achieve isolation, 5.5 ± 2.8 minutes/vein, was significant shorter than in the bipolar group, 7.6 ± 4.1 minutes/vein (P < 0.01). Mean procedure and fluoroscopy durations per vein were 19% to 28% shorter in the unipolar plus bipolar group. Conclusion: Segmental ostial ablation to isolate the pulmonary veins can be achieved more efficiently and with less radiofrequency energy when guided by both unipolar and bipolar recordings than by bipolar recordings alone. [source]

    Effects of Prenatal Alcohol Exposure on Brain Activation During an Arithmetic Task: An fMRI Study

    ALCOHOLISM, Issue 11 2009
    Priya Santhanam
    Background:, While behavioral studies have established that prenatal alcohol exposure (PAE) can result in diminished arithmetic processing capability, the underlying neural correlates of this deficit are still unclear. The aim of the present study was to use functional magnetic resonance imaging to determine the effect of PAE on neuronal activation during a subtraction task. Methods:, Participants were young adults from a low socio-economic status population who were identified prenatally; the sample consisted of healthy unexposed controls (n = 17) and PAE who were subdivided based on the presence (n = 19) or absence of physical dysmorphic signs (n = 18). Multiple regression analysis was used to determine extent of activation and percent signal change during arithmetic processing, using a letter-matching task as the baseline. Region of interest analysis of activation was performed in the native space and normalized for each individual to compensate for the considerable variability in head size observed in the alcohol-exposed population. Results:, An exposure-dependent response was observed in task performance and neuronal activation. Dysmorphic PAE individuals showed significantly lower task-related performance and activation in regions known to be associated with arithmetic processing, including left superior and right inferior parietal regions and medial frontal gyrus, while the nondysmorphic PAE group was generally intermediate but not significantly different from the control group in task performance and activation. Conclusions:, Results indicate that there is a range of effects of PAE on arithmetic processing and that the severity of this deficit may be dependent on degree of impairment demonstrated by the exposed individual. Evidence of physical dysmorphia may be indicative of functional damage to regions associated with arithmetic calculation, resulting in markedly impaired neuronal recruitment. [source]

    Myocardium Extending from the Left Atrium onto the Pulmonary Veins: A Comparison Between Subjects with and Without Atrial Fibrillation

    PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 10 2001
    MINORU TAGAWA
    TAGAWA, M., et al.: Myocardium Extending from the Left Atrium onto the Pulmonary Veins: A Comparison Between Subjects with and Without Atrial Fibrillation. Rapid discharges from the myocardium extending from the left atrium onto the pulmonary vein (PV) have been shown to initiate AF, and AF may be eradicated by the catheter ablation within the PV. However, if there is any difference in the distribution patterns of the myocardial sleeve onto the PV between the subjects with and without AF is to be determined. Twenty-one autopsied hearts were examined. Eleven patients previously had AF before death and another 10 patients had normal sinus rhythm as confirmed from the medical records including ECGs before death. After exposing the heart, the distance to the peripheral end of the myocardium was measured from the PV-atrial junction in each PV. Then, the PVs were sectioned and stained and the distal end of myocardium and the distribution pattern were studied. The anteroposterior diameter of the left atrium was also measured. In 74 of 84 PVs, the myocardium extended beyond the PV-atrial junction. The myocardium was localized surrounding the vascular smooth muscle layer forming a myocardial sleeve. The peripheral end of the myocardial sleeve was irregular and the maximal and minimal distances were measured in each PV. The myocardium extended most distally in the superior PVs compared to the inferior ones and the maximal distance to the peripheral end was similar between the AF and non-AF subjects (8.4 ± 2.8 vs 8.7 ± 4.4 mm for the left superior and 6.5 ± 3.5 vs 5.1 ± 3.9 mm for the right superior PV, respectively). A significant difference was found in the maximal distance in the inferior PVs: 7.3 ± 4.6 vs 3.3 ± 2.8 mm for the left (P < 0.05) and 5.7 ± 2.4 vs 1.7 ± 1.9 mm for the right inferior PV (P < 0.001) in the subjects with and without AF, respectively. The diameter of left atrium was slightly dilated in AF patients but insignificantly (4.1 ± 0.1 vs 3.6 ± 0.1 cm, P > 0.07). The myocytes on the PV were less uniform and surrounded by more fibrosis in patients with AF compared to those without AF. In conclusion, the myocardium extended beyond the atrium-vein junction onto the PVs. The distribution patterns of the myocardium was almost similar between subjects with and without AF, but the histology suggested variable myocytes in size and fibrosis in patients with AF. [source]