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41.
42.

Aim

Optimization of coronary sinus (CS) lead position to the latest activated left ventricular (LV) area is important to increase cardiac resynchronization therapy (CRT) response. We aimed to detect the relationship between coronary sinus lead delay index (CSDI) and echocardiographic, electrocardiographic response to CRT treatment.

Methods

We prospectively included 137 consecutive patients with heart failure (HF) diagnosis, QRS ≥ 120 ms, left bundle branch block (LBBB), New York Heart Association score (NYHA) II–IV, LV ejection fraction (LVEF) <35% and scheduled for CRT (84 male, 53 female; mean age 65.1 ± 10.1 years). Echocardiographic CRT response was defined as ≥15% reduction in LV end‐systolic volume (LVESV). CS lead sensing delay was calculated as the time interval from the onset of surface QRS wave to the onset of depolarization wave recorded from the CS lead by using the CS pacing lead as a bipolar electrode. CSDI was calculated by dividing the CS lead sensing delay by the QRS duration.

Results

LVESV reduction was associated with baseline QRS width (r = .257, p = .002), QRS narrowing (r = .396, p < .001), CSDI (r = .357, p < .001), and NT‐proBNP (r = ?0.213, p = .022) in bivariate analysis. In logistic regression analysis, CSDI was found to be only independent parameter for predicting significant LVESV reduction (Beta = 0.318, p < .001). CSDI was also found to be significantly associated with LVEF increase (r = .244, p = .004) and QRS narrowing (r = .178, p = .046).

Conclusion

CSDI may be used as a marker to predict the favorable response to CRT. It may be useful to integrate CSDI to CRT implantation procedure in order to minimize nonresponders.
  相似文献   
43.
Hepatocytes are hypothesized to continuallystream from the portal tract to the terminal hepaticvein. By this model, when a cell divides, one of itsprogeny replaces the dividing ancestor and the other is displaced into a more remote location. Thepresent experiment aims to demonstrate thathypothyroidism affects liver cell turnover. Thirty maleadult rats were divided into two groups. One receivedmethimazole for two weeks and the other served as control.Each rat was injected intraperitoneally with 18.5 KBq[3H]thymidine/g body weight. Rats were killedafter 1 hr and two and four weeks. Autoradiography was done. The distance of the labeled cells fromthe portal tract was measured. The mean TSH levels ofthe methimazole-treated group and controls were 1.45 and0.25 mM/liter, respectively (P < 0.01). Hepatocyte streaming was lower in hypothyroid (1.8m/day) than in untreated rats (2.5 m/day) (P< 0.01). The respective labeling indices 1 hr afterlabeling were 0.9% and 1.24% (P < 0.05). We concludethat hypothyroidism diminishes hepatocyte and littoral cellturnover and slows down their streaming.  相似文献   
44.
OBJECTIVE: Thoracic impedance cardiography (TIC) is a noninvasive method which has proved to be useful in monitoring the haemodynamic status of the patients. In this study, we evaluated the TIC findings in patients with pericardial effusion and cardiac tamponade. METHODS AND RESULTS: The study consisted of patients with pericardial effusion with (group A) or without (group B) cardiac tamponade (CT). The stroke volume, cardiac output and ejection fraction was measured by both echocardiography and TIC. The measurements were done at baseline in both groups and following pericardiocentesis in group A. The variables were compared by linear regression analysis, paired sample's t test and chi-square test. The study included 32 patients. Group A consisted of 16 patients and group B of 14 patients. Two patients were excluded from comparisons because of insufficient quality of the echocardiographic examination. There were no significant differences between group A and B with regard to demographic features. Both echocardiographic and TIC measurements at baseline revealed decreased cardiac output, EDV and SV in group A and EF was not different. Linear regression analysis revealed that echocardiography and TIC were in significant correlation with regard to cardiac output, enddiastolic volume, stroke volume (p < 0.01) but not ejection fraction (p = 0.8910). The correlation was also present after pericardiocentesis. CONCLUSIONS: TIC can be safely used in patients with pericardial effusion. It provides suggestive data for the diagnosis of CT and can be used as a means of monitoring the results of the pericardiocentesis.  相似文献   
45.
Ectopic thyroid gland in the porta hepatis and lingua.   总被引:2,自引:0,他引:2  
A rare case of an ectopic thyroid gland in the porta hepatis and in the tongue in an asymptomatic euthyroid 24-year-old woman is reported. A solitary inhomogeneous, hypoechogenic and hyperechogenic mass in the porta hepatis was accidentally discovered by ultrasonography. Subsequent computed tomography demonstrated a heterogeneous, well-defined tumor with small calcifications without signs of environmental invasion. A hemangioma and focal nodular hyperplasia were excluded by blood pool and hepatobiliary scintigraphy. Surprisingly, fine-needle aspiration cytology revealed normal thyroid tissue. (123)I-scintigraphy confirmed the presence of ectopic dual thyroid tissue in the hepatic porta and lingua. At clinical inspection the lingual thyroid gland was palpable and visible, and appeared solid and spheroidal. The subhepatic, ectopic thyroid mass was resected. Postoperatively, thyroid hormone replacement was started to prevent an enlargement of the lingual thyroid. Today, 4 years after surgery, the patient remains euthyroid.  相似文献   
46.
Background: Until recently no clinical studies had reported precise right atrium (RA) mapping when performing induction of atrial flutter (AFI). We studied the mode of tachycardia initiation in 16 patients (pts) referred for radiofrequency (RF) AFl ablation. AFl induction was performed at the beginning of the procedure (n &equals; 10), or after previous AFl termination during RF delivery (n &equals; 6). Detailed analysis of AFl initiation was provided by duodecapolar (Halo) and multipolar catheters positioned in the peritricuspidian region at the lateral right atrial wall (LRA), the inferior vena cavatricuspid annulus (IVC-TA) isthmus and the interatrial septum. Induction was obtained during incremental pacing (IAP) (15 pts) or programmed stimulation (1 pt) from the proximal coronary sinus (PCS).Results: Atrial flutter with counterclockwise (CCW) RA rotation was induced in all pts by PCS pacing. During PCS IAP, at long pacing cycle lengths, impulse propagated in a clockwise (CW) direction through the IVC-TA isthmus and then upward at low (L) LRA. This led to a collision at the mid LRA with another wave front propagating in a CCW direction at the septum. IAP from PCS induced a progressive delay of propagation at the IVC-TA isthmus resulting in a prolongation of the PCS-Mid Isthmus interval from 85&plusmn;29 to 151&plusmn;42 msec. At same pacing cycle lengths (CL), the PCS-HLRA interval was comparatively less prolonged, from 75&plusmn;12 to 105&plusmn;18 msec, p &equals; 0.0007. This preferential slowing of conduction between PCS and mid isthmus, during IAP from PCS, was associated with a displacement of the zone of collision to the Low LRA. Finally a CW functional block occurred at the IVC-TA isthmus and CCW AFl was induced through a period of transient concealed entrainment. The paced CL required to initiate flutter ranged from 290 to 180 msec and the mean CL of induced atrial flutter was 254&plusmn;27 msec.Conclusions: The IVC-TA isthmus has decremental properties and exhibits wenckebach phenomenon during incremental PCS pacing. Initiation of a counterclockwise flutter by PCS pacing is associated with appearance of a functional unidirectional block at the IVC-TA isthmus.  相似文献   
47.
Introduction: This study evaluated CD39 in a porcine model of balloon angioplasty and in plasma of patients undergoing percutaneous intervention. CD39 (E-NTPDase1), is the endothelial ecto-ADPase inhibiting platelet function via hydrolysis of released platelet ADP.Methods and Results: A recombinant soluble form of CD39 (solCD39) given intravenously to pigs had an elimination half life of 5–7 days, increased the bleeding time to an extent similar to aspirin, and inhibits platelet aggregation by > 90%. Platelet counts and clot retraction remained normal following solCD39 administration. In a pig model of acute coronary balloon injury, solCD39 resulted in non-statistically significant decreases in platelet (7.7 ± 1.4 versus 11.7 ± 3.4) and fibrin (3.5 ± 0.4 versus 4.2 ± 0.7) deposition ratios. Adding ex vivo to human platelet rich plasma (PRP) solCD39 produced nearly 100% inhibition of ADP-induced platelet aggregation. A dose-response effect of solCD39 on platelet aggregation induced by collagen or a thrombin receptor activating peptide (TRAPSFLLRN) was noted in PRP obtained from volunteers and patients receiving aspirin, clopidogrel or ticlopidine. SolCD39 also provided additional and complete inhibition of TRAP-induced platelet aggregation in PRP from patients who had received abciximab, aspirin and clopidogrel.Conclusions: SolCD39, a novel inhibitor of platelet activation and recruitment with a relatively long half-life appears to be well tolerated and is a potent inhibitor of ADP-, collagen-, or TRAP-induced platelet activation. Its potential use in percutaneous coronary intervention requires further study.Abbreviated Abstract. E-NTPDase1/CD39 is the endothelial ecto-ADPase responsible for inhibition of platelet function. A recombinant soluble form (solCD39) had an elimination half life of 5–7 days in pigs, elevated bleeding times similar to aspirin, did not affect clot retraction, and inhibited platelet aggregation by > 90%. When combined with standard heparin therapy in a pig model of acute coronary balloon injury, solCD39 resulted in a trend toward a decrease in platelet and fibrin deposition. SolCD39 added ex vivo to human platelet rich plasma yielded nearly 100% inhibition of ADP-induced platelet aggregation and provided further inhibition when combined with standard therapy.Supported in part by a Merit Review grant from the Department of Veterans Affairs (A.J.M., M.J.B.), and by National Institutes of Health grants HL 47073, HL 46403, and NS 41462 (A.J.M., M.J.B.) and by Immunex Corp., Seattle, WA.  相似文献   
48.
Hemophilia is a hereditary disease with impaired blood coagulation due to a genetic deficiency of blood coagulation factors. The development of inhibitors further complicates the course of the disease and management. The case is here reported of a haemophilia patient who presented with coexisting development of high titer inhibitor with Gastrointestinal Stromal Tumor (GIST) diagnosis and was admitted with upper gastrointestinal system bleeding. The patient had no prior history of inhibitor presence. During all procedures including surgery, excellent hemostasis was achieved with rFVIIa treatment and no hemorrhagic complication was observed. To the best of our knowledge, this constitutes the first reported case of GIST associated with inhibitor development in a hemophilia A patient.  相似文献   
49.

Purpose

The aim of our study is to research the role and efficacy of cerebral oximetry in predicting neurologic prognosis when applied during TTM to patients experiencing coma after CA.

Methods

This study was performed on surviving adult comatose patients after CA treated with TTM. The average scores of rSO2 was measured at 6 h intervals for the first 2 days and once a day for the following 3 days with a NIRS device during TTM. The CPC scale was used to define the neurologic outcomes of patients. We compared the correlations of rSO2 values between good (CPC 1–2) and poor (CPC 3–5) neurologic outcomes in CA patients.

Results

There was no statistically significant difference identified between the prognosis groups in terms of rSO2, CPR durations, hemoglobin values and admission body temperature (p > 0.05). When the variation in rSO2 values over time is investigated, though there was no significant difference between the good and poor prognosis groups, it appeared to fall in the first 6 h in both prognosis groups. The median NT-proBNP and lactate values were observed to be higher in the poor prognosis group.

Conclusion

There is no significant correlation between rSO2 values and neurologic outcomes. Multimodal monitoring methods may be useful and further studies with a larger patient population are necessary in this area.  相似文献   
50.
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