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Background/aim: This study aimed to evaluate pulmonary vein (PV) anatomy using 256-slice computed tomography (CT), which may be necessary for electrophysiologists to know before radiofrequency catheter ablation (RFCA) therapy.
Materials and methods:A total of 102 patients with paroxysmal and persistent atrial fibrillation underwent 256-slice cardiac CT angiography prior to catheter ablation. PV morphology, ostial diameter, ostial orientation, and distance from ostium to first bifurcation were evaluated using three-dimensional volume-rendering and multiplanar-reformatting technology.
Results:We found that 72.5% of patients had four conventional PVs. On the right, 22.5% of patients had one accessory PV, 4.9% had 2 accessory PVs, 1% had one common PV, and 1% had one top vein. On the left, 27.5% of patients had one common PV. Additionally, 9.8% of patients had bilateral PV variation. Ostial size was larger for superior PVs than inferior PVs and larger for right PVs than left PVs. PV ostia on the right tended to be more circular. There was a rather wide variation of projective angle and distance from ostium to first bifurcation. Early branching occurred more often in the right inferior PV.
Conclusion:256-Slice CT can depict PV anatomy and afford substantial data, which will help electrophysiologists conduct the RFCA procedure safely and efficiently.
BackgroundThyrotropin-secreting pituitary adenomas (TSHomas) are a rare cause of hyperthyroidism. Somatostatin analogs have proved to be effective for inhibiting pituitary hormones secretion, working via interactions with somatostatin receptors (SSTRs). Moreover, antiproliferative activity of somatostatin analog is now demonstrated in several studies. In the present study, we determined the relative predominance of SSTR2 and SSTR5 subtypes among the different types of adenomas, especially TSHoma, and investigated the relationship between efficacy of short-term octreotide (OCT) treatment and SSTR expression.Material/MethodsSerum hormone determinations and histological findings in resected tissue resulted in 5 diagnoses: 16 TSHomas, 8 acromegaly, 3 prolactinomas, 3 corticotropinomas, 4 clinically nonfunctioning adenomas (NFPAs), and 4 normal pituitary specimens. IHC was performed on formalin-fixed and paraffin-embedded tissue in tissue microarrays.ResultsIHC of SSTR subtypes in the different cohorts showed SSTR2 staining intensity scores higher than SSTR5 in TSHoma, acromegaly and prolactinoma, whereas the expression of SSTR5 was stronger than SSTR2 in corticotropinoma and NFPA. SSTR2 and SSTR5 expressions were significantly higher in TSHoma than in other pituitary adenomas. OCT treatment for a median of 8.4 days (range: 3–18 days) and with a total median dose of 1.9 mg (range: 0.9–4.2 mg) showed a significant decrease of thyroid hormone levels (TSH [μIU/ml] in all patients. Patients with low SSTR5 expression presented a significantly higher TSH suppression rate (P values <0.05).ConclusionsThe present data confirm that somatostatin analogs should be considered as a medical alternative to surgical treatment, especially in patients with TSHoma, and short-term response to OCT therapy may be related to the expression of SSTR5.
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