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排序方式: 共有9020条查询结果,搜索用时 134 毫秒
161.
Mapping and ablation of polymorphic ventricular tachycardia after myocardial infarction 总被引:6,自引:0,他引:6
Szumowski L Sanders P Walczak F Hocini M Jaïs P Kepski R Szufladowicz E Urbanek P Derejko P Bodalski R Haïssaguerre M 《Journal of the American College of Cardiology》2004,44(8):1700-1706
OBJECTIVES: The goal of this study was to describe the mapping and ablation of polymorphic ventricular tachycardia (VT) after myocardial infarction (MI). BACKGROUND: The initiating mechanisms of polymorphic VT after MI have not been reported. METHODS: Five patients (four males; age 61 +/- 7 years) with recurrent episodes of polymorphic VT after anterior MI (left ventricular ejection fraction 32 +/- 7%) despite revascularization and antiarrhythmic drugs were studied. All patients demonstrated frequent ventricular premature beats (PBs) initiating polymorphic VT. Pace mapping and activation mapping were used to identify the earliest site of PB activity. The presence of a Purkinje potential preceding PB defined its origin from the Purkinje network. Electroanatomic voltage mapping was performed to delineate the extent of MI. RESULTS: The PBs were observed in all cases to arise from the Purkinje arborization in the MI border zone. These PBs were right bundle-branch block in all five patients, with morphologic variations in the limb leads in four; one also had a left bundle-branch block morphology. The coupling interval of the PB to the preceding QRS complex demonstrated significant variations (320 to 600 ms). During PB, the Purkinje potential at the same site preceded the QRS complex by 20 to 160 ms and was associated with different morphologies. Repetitive Purkinje activity was documented during polymorphic VT. Splitting of Purkinje activity and Purkinje to muscle conduction block were also observed. Ablation at these sites eliminated all PBs. At 16 +/- 5 months follow-up using defibrillator memory interrogation, no patient has had recurrence of arrhythmia. CONCLUSIONS: The Purkinje arborization along the border-zone of scar has an important role in the mechanism of polymorphic VT in patients after MI. Ablation of the local Purkinje network allows suppression of polymorphic VT. 相似文献
162.
Asynchronism and right ventricular pacing 总被引:2,自引:0,他引:2
Thambo JB Bordachar P Lafitte S Crepin D Garrigue S Reuter S Roudaut R Haïssaguerre M Clementy J Jimenez M 《Archives des maladies du coeur et des vaisseaux》2005,98(5):519-523
In patients with congenital heart block (CHB), dual-chamber pacing restores physiological heart rate and atrio-ventricular synchronization. However, patients with narrow QRS junctional escape rhythm may be deleteriously affected by long-term, permanent, apical ventricular pacing. We assessed the impact of apical ventricular pacing on echocardiographic ventricular dyssynchrony and hemodynamic parameters. METHODS: Fourteen CHB adults (23 +/- years, 58% male), with a DDD transvenous pacemaker and a junctional escape rhythm (QRS<120 ms) before implantation, were studied. Echocardiography coupled with tissue Doppler imaging (TDI) and Strain rate was performed in spontaneous rhythm (VVI mode 30/mn) and during atrio-synchronized ventricular pacing. RESULTS: The heart rate (43 +/- 09 vs 68 +/- 07: p<0.01), cardiac output (2.9 +/- 0.7 vs 3.7 +/- 0.6 L/min) and left ventricular filling time (325 +/- 38 vs 412 +/- 51 ms; p<0.01) were significantly less in the escape spontaneous rhythm compared with atrio-ventricular synchronized apical pacing. However, interventricular dyssynchrony (28 +/- 12 vs 59 +/- 25 ms, p<0.05), intra-left ventricular dyssynchrony (36 +/- 11 vs 57 +/- 29 ms; p<0.05), extent of left ventricular myocardium displaying delayed longitudinal contraction (26 +/- 10 vs 39 +/- 17%: p<0.05) were significantly less in the escape rhythm compared with paced rhythm. CONCLUSION: Once implanted with a DDD pacemaker, CHB patients present with increased cardiac output secondary to the restoration of physiological heart rate and improved diastolic function. However, the apical site is not optimal, as it creates detrimental ventricular dyssynchrony in patients with previous nearly physiological ventricular activation. Alternative pacing sites should be investigated. 相似文献
163.
Harald?S?derb?ckEmail authorView authors OrcID profile Ulf?Gunnarsson Per?Hellman Gabriel?Sandblom 《International journal of colorectal disease》2018,33(10):1411-1417
Background
Our knowledge on the incidence of incisional hernia and risk factors for developing incisional hernia following surgery for colorectal cancer is far from complete.Methods
All procedures registered in the Swedish Colorectal Cancer Register (SCRCR) 2007–2013 were identified. Patients with comorbid disease diagnoses, registered at admissions and visits prior to the procedure and relevant to this study, were obtained from the National Patient Register (NPR). These diagnoses included cardiovascular disease, connective tissue disorders, liver cirrhosis, renal failure, diabetes, chronic obstructive lung disease and chronic inflammatory conditions. Data on occurrence of incisional hernias were obtained by combining data from the SCRCR and the NPR (International Classification of Diseases code).Results
During 2007–2013, 39,984 procedures were registered in the SCRCR. After excluding laparoscopic procedures, procedures repeated on the same patient, procedures with concomitant liver resection and procedures without laparotomy, 28,913 cases remained for analysis. Five years after surgery, the cumulative incidence of incisional hernia was 5.3%. In multivariate proportional hazard analysis, significantly increased risk for incisional hernia was found for the male gender (hazard ratio [HR] 1.40, 95% confidence interval [CI] 1.21–1.62), operation time exceeding 180 min (HR 1.25, CI 1.08–1.45), body mass index (BMI) >?30 (HR 1.78, CI 1.51–2.09), age <?70 years (HR 1.34, CI 1.16–1.56) and postoperative wound complication (HR 2.09, CI 1.70–2.58).Discussion
Men, patients younger than 70 years and patients with BMI?>?30 face a higher risk for incisional hernia. The risk is also increased in cases where the procedure takes longer than 3 h or where postoperative wound complications occur. These patients will benefit from measures aimed at preventing the development of incisional hernia.164.
Solal-Céligny P Roy P Colombat P White J Armitage JO Arranz-Saez R Au WY Bellei M Brice P Caballero D Coiffier B Conde-Garcia E Doyen C Federico M Fisher RI Garcia-Conde JF Guglielmi C Hagenbeek A Haïoun C LeBlanc M Lister AT Lopez-Guillermo A McLaughlin P Milpied N Morel P Mounier N Proctor SJ Rohatiner A Smith P Soubeyran P Tilly H Vitolo U Zinzani PL Zucca E Montserrat E 《Blood》2004,104(5):1258-1265
The prognosis of follicular lymphomas (FL) is heterogeneous and numerous treatments may be proposed. A validated prognostic index (PI) would help in evaluating and choosing these treatments. Characteristics at diagnosis were collected from 4167 patients with FL diagnosed between 1985 and 1992. Univariate and multivariate analyses were used to propose a PI. This index was then tested on 919 patients. Five adverse prognostic factors were selected: age (> 60 years vs 60 years), Ann Arbor stage (III-IV vs I-II), hemoglobin level (< 120 g/L vs 120 g/L), number of nodal areas (> 4 vs 4), and serum LDH level (above normal vs normal or below). Three risk groups were defined: low risk (0-1 adverse factor, 36% of patients), intermediate risk (2 factors, 37% of patients, hazard ratio [HR] of 2.3), and poor risk ( 3 adverse factors, 27% of patients, HR = 4.3). This Follicular Lymphoma International Prognostic Index (FLIPI) appeared more discriminant than the International Prognostic Index proposed for aggressive non-Hodgkin lymphomas. Results were very similar in the confirmation group. The FLIPI may be used for improving treatment choices, comparing clinical trials, and designing studies to evaluate new treatments. 相似文献
165.
Endocrine disorders seen in antiphospholipid syndrome are rare. To date, these disorders have generally involved Addison's disease. Recently reports have appeared of a few cases of primary or secondary hypopituitarism associated with primary antiphospholipid syndrome. We report the case of a young female patient who presented neuroendocrine symptoms during the postpartum period associated with an antiphospholipid syndrome. Hormone assessment showed complete anterior hypopituitarism and antiphospholipid antibodies were positive. We discuss the clinical, biological and radiological features observed in our patient and compare results with cases reported in the literature. This case illustrates the importance of screening for antiphospholipid syndrome in the etiological work-up of hypopituitarism associated with a history of recurrent thrombosis. 相似文献
166.
167.
Kristian?SolteszEmail authorView authors OrcID profile Trygve?Sj?berg Tomas?Jansson Rolf?Johansson Anders?Robertsson Audrius?Paskevicius Quiming?Liao Guangqi?Qin Stig?Steen 《Journal of clinical monitoring and computing》2018,32(3):429-437
The purpose of this concept study was to investigate the possibility of automatic mean arterial pressure (MAP) regulation in a porcine heart-beating brain death (BD) model. Hemodynamic stability of BD donors is necessary for maintaining acceptable quality of donated organs for transplantation. Manual stabilization is challenging, due to the lack of vasomotor function in BD donors. Closed-loop stabilization therefore has the potential of increasing availability of acceptable donor organs, and serves to indicate feasibility within less demanding patient groups. A dynamic model of nitroglycerine pharmacology, suitable for controller synthesis, was identified from an experiment involving an anesthetized pig, using a gradient-based output error method. The model was used to synthesize a robust PID controller for hypertension prevention, evaluated in a second experiment, on a second, brain dead, pig. Hypotension was simultaneously prevented using closed-loop controlled infusion of noradrenaline, by means of a previously published controller. A linear model of low order, with variable (uncertain) gain, was sufficient to describe the dynamics to be controlled. The robustly tuned PID controller utilized in the second experiment kept the MAP within a user-defined range. The system was able to prevent hypertension, exceeding a reference of 100 mmHg by more than 10%, during 98% of a 12 h experiment. This early work demonstrates feasibility of the investigated modelling and control synthesis approach, for the purpose of maintaining normotension in a porcine BD model. There remains a need to characterize individual variability, in order to ensure robust performance over the expected population. 相似文献
168.
Aykut Sarıtaş Burcu Acar Çinleti Çiler Zincircioğlu Uğur Uzun Işıl Köse Nimet Şenoğlu 《The American journal of emergency medicine》2018,36(12):2236-2241
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169.
170.