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61.
The authors would like to present the difficulties in differentiation of diabetes mellitus type 1 and type 2 in adolescence on the basis of two 17 years-old patients. In both patients' cases the following symptoms: polydipsia, polyuria and weight loss with hyperglycemia and glycosuria have been observed for a few months. During laboratory studies some additional abnormalities were observed: elevated HbA1c, dyslipidemia and high level of liver enzymes. Normal level of insulin as well as C-peptide lack of ketonuria and negative parameters of autoimmunologic reaction the supported diagnosis of diabetes mellitus type 2. Due to insulin therapy and metformin a correct level of glycemia was achieved. CONCLUSION: Decompensated diabetes mellitus type 2 in adolescents may be difficult to differentiate with type 1.  相似文献   
62.
The selective ablation of the recurrent ventricular tachycardia (VT) in a 75-year old patient after extensive inferior myocardial infarction (24 years ago), with low ejection fraction was performed. In 1995 the cardioverter-defibrillator was implanted due to recurrent, symptomatic VT. The coronary angiography in 1995 and in 2006 revealed the occlusion of the right coronary and the circumflex arteries. One year after implantation, he had electrical storm caused by proarrhythmic effect of amiodarone with prolongation of QT/QTc interval. During follow up episodes of VT (approximately 5/year) were successfully terminated by ATP and rarely by cardioversion. Recently, the patient was admitted to the hospital because of the very frequent (25/day) episodes of slow (500-560 ms), sustained ventricular tachycardia. The pharmacological treatment was unsuccessful. CARTO mapping and entrainment pacing revealed VT circuit around mitral annulus. A few applications at the paraseptal part of the mitral isthmus terminated VT, which was no longer inducible. During following days there were no VTs requiring ICD interventions.  相似文献   
63.
Pawlak A  Gil RJ  Walczak E  Fidziańska A 《Kardiologia polska》2007,65(3):229-35; discussion 236
BACKGROUND: Desmin plays one of the key roles in cardiomyocytes. The protein protects the integration of the cell and has the following actions: mechanical, structural and regulatory. Observed abnormalities of its activity have been associated with worsening of heart failure (HF). AIM: Evaluation of desmin activity detected with immunohistochemical (IHC) and immunofluorescent (IF) staining in cardiomyocytes in patients with chronic HF. METHODS: The study population comprised 37 patients (mean age 46.5+/-15.28 years, 83.8% males) with diagnosed HF of unknown aetiology, who underwent myocardial biopsy. Coronary angiography was performed to exclude presence of significant coronary artery disease. Heart failure was diagnosed based on clinical assessment and echocardiography showing left ventricular ejection fraction below 45%. RESULTS: The IHC and IF evaluation of cardiomyocyte desmin showed that these methods were consistent with respect to classification of 31 specimens (83.8%), while being discrepant in 6 (16.2%) cases. Desmin detection in myocardial biopsy specimens with IHC staining showed normal amounts of this protein in 11 (29.8%) cases, excess in 18 (48.6%) patients and deficiency in 8 (21.6%) cases, whereas in IF stained specimens respective values were 12 (32.4%), 15 (40.6%) and 10 (27%). No significant differences were found between all desmin groups (i.e. normal level, excessive and deficiency) evaluated with IHC and IF staining (p=0.39; p=0.25; p=0.31, respectively). CONCLUSIONS: The IHC and IF methods allow evaluation of desmin activity in cardiomyocytes and division into three types of expression. Both methods have high consistency. The IHC, which is the more available method, seems to be a sufficient assay.  相似文献   
64.
A patient with a 6-year history of drug-resistant, recurrent arrhythmias (AT/AFL, single SVEBs, pairs and series) developed arrhythmogenic cardiomyopathy. Conduction block between coronary sinus (CS) and atria caused periodical change of tachycardia's rate. Successful RF ablation performed in the middle of CS at a place of spike potentials of a 284 ms CL. During a 6-years follow-up after ablation, ejection fraction increased from 38 to 59% and the quality of life improved significantly.  相似文献   
65.
66.
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   
67.
BACKGROUND: Atrial fibrillation (AF) in patients with WPW syndrome may be a life-threatening arrhythmia. AIM: To identify risk factors of AF and their prognostic significance in patients with WPW syndrome. METHODS: Clinical and electrophysiological parameters of 239 patients with WPW syndrome, who underwent successful RF ablation, were analysed using logistic regression and multivariate analysis. One hundred eight patients had no history of AF whereas the remaining 81 patients had previous spontaneous AF episodes. Long-term follow-up data (mean 29+/-23 months, range 1-99 months) were available in 136 patients (87 without AF and 49 with AF). RESULTS: Patients with AF were significantly older, more frequently of male gender and had more often a history of syncope than patients without AF. There were two peaks of AF occurrence - in the third and in the fifth decade of life. Fourteen patients had a history of ventricular fibrillation - 11 patients with AF vs 3 patients without AF (p=0.0016). Patients with a history of AF were more prone to AF induced during electrophysiological study and had less frequently concealed accessory pathways. CONCLUSIONS: Age, gender and a history of syncope are the independent risk factors of AF in patients with WPW syndrome. Anterograde conduction via accessory pathway is of major importance in the development of AF. RF ablation of an accessory pathway should be performed early because the risk of the procedure is small and there is an increasing risk of AF with ageing.  相似文献   
68.
A vicious circle of interactions between dilated cardiomyopathy and longstanding persistent AF/AFL may cause symptoms of advanced congestive heart failure. In a 31-year-old patient with diagnosis of familial dilated cardiomyopathy and permanent AF lasting for five years, gradually decreased left ventricular ejection fraction (LVEF) and increased diameter of heart chambers - left ventricular diastolic dimension (LVdD) 7.7 cm, left atrium (LA) 5.4 cm, and LVEF 15% were noted. Pharmacological treatment was ineffective Successful RF ablation of AF/AFL substrate (CTI block, PVs isolation, CFAE ablation, roof and MIG line, CS applications) reversed symptoms of significant heart remodeling (LVdD 5.9 cm, LA 4.3 cm, LVEF 50%).  相似文献   
69.
We describe a case of a 76-year-old patient with advanced block in the His-Purkjnie system, who underwent implantation of a cardioverter-defibrillator with cardiac resynchronisation therapy. Complete heart block occurred during the insertion of the coronary sinus cathether. The implantation of the left ventricular (LV) lead was impossible due to difficult anatomy of the coronary venous system. The right ventricular pacing caused the further prolongation of the QRS duration and exacerbation of heart failure symptoms. Thus, the LV lead was successfully implanted during the second procedure after the balloon venoplasty of the lateral cardiac vein. The biventricular pacing was successful during 4 months follow-up.  相似文献   
70.
A case of a 51 year old patient with a history of myocardial infarction (MI) and recurrent ventricular tachycardia (VT) is presented. Three months after MI the patient underwent coronary angioplasty and one year later received prophylactic implantable cardioverter-defibrillator (ICD) due to complex ventricular arrhythmias, detected on Holter ECG monitoring, and depressed left ventricular ejection fraction. Later on the patient started to experience palpitations and ICD shocks during physical activity (cycling). Interrogation of the ICD memory showed appropriate shocks due to slow (160 betas/min) VT. The device was reprogrammed and new antitachycardia pacing (ATP) algorithms were enabled, however, it occurred proarrhythmic due to the ATP-induced acceleration of VT rate. Finally, in April 2005 he received 37 appropriate ICD shocks during a few hours. The patient was selected for RF ablation and underwent successful procedure with the use of the electro-anatomical CARTO mapping system.  相似文献   
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