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1.
Int J Obes (Lond) ; 39(8): 1236-40, 2015 Aug.
Article in English | MEDLINE | ID: mdl-25835554

ABSTRACT

BACKGROUND AND OBJECTIVES: Oxidative stress and the insulin-resistant state are thought to be key components in the pathogenesis of pediatric nonalcoholic fatty liver disease (NAFLD). Heme oxygenase (HO) is important in the defense against oxidative stress. This study aimed to assess the association of HO-1 gene promoter polymorphism and insulin resistance with NAFLD among obese children. METHODS: A total of 101 obese children aged 6-17 years were recruited. Anthropometric, serum biochemical variables and biomarkers for glucose and insulin metabolism were measured. We screened the allelic frequencies of (GT)n repeats in the HO-1 gene promoter among these obese children. NAFLD was determined through liver ultrasonography. Because the distribution of numbers of (GT)n repeats was bimodal, we divided the alleles into two classes: class S included shorter (27) repeats, and class L included longer (⩾27) repeats. We assessed the effects of the length of (GT)n repeats in HO-1 gene promoter on pediatric NAFLD. RESULTS: Of the 101 obese subjects, 27 (26.7%) had NAFLD. The alanine aminotransferase level was higher in patients carrying L alleles (L/L and L/S) than patients with S alleles (S/S) (46.2±49.3 IU|(-1) versus 30.2±20.1 IU|(-1); P=0.027). The significant risk factors for pediatric NAFLD were patients carrying L alleles (L/L and L/S) (odds ratio (OR)=18.84; 95% confidence interval (CI): 1.45-245.22; P=0.025), homeostasis model assessment of insulin resistance (OR=1.40; 95% CI: 1.07-1.83; P=0.014) and age (OR=1.24; 95% CI: 1.03-1.50; P=0.025). CONCLUSION: In this hospital-based study, the obese children with longer GT repeats in the HO-1 gene promoter and insulin resistance were susceptible to NAFLD.


Subject(s)
Genetic Predisposition to Disease/genetics , Heme Oxygenase-1/genetics , Non-alcoholic Fatty Liver Disease/etiology , Oxidative Stress/genetics , Pediatric Obesity/complications , Adolescent , Child , Female , Humans , Insulin Resistance , Male , Microsatellite Repeats , Non-alcoholic Fatty Liver Disease/epidemiology , Non-alcoholic Fatty Liver Disease/genetics , Pediatric Obesity/epidemiology , Pediatric Obesity/genetics , Polymorphism, Genetic , Promoter Regions, Genetic , Risk Factors , Taiwan/epidemiology
2.
Eur J Neurol ; 21(10): 1285-91, 2014 Oct.
Article in English | MEDLINE | ID: mdl-24909847

ABSTRACT

BACKGROUND AND PURPOSE: Orolingual angioedema (OA) is an uncommon but potentially life-threatening complication of treatment with recombinant tissue plasminogen activator (rt-PA; alteplase) during acute ischaemic stroke. This study aimed to determine the incidence of rt-PA-related OA in an Asian stroke population and the risk of pre-stroke anti-hypertensive drug use for development of this complication. METHODS: A multi-center stroke registry was used to identify the pre-stroke medications of acute ischaemic stroke patients receiving intravenous rt-PA from January 2002 to December 2013. The clinical manifestations of rt-PA-related OA were recorded and the incidence of this complication was determined. The risks of pre-stroke use of different anti-hypertensive agents for the occurrence of rt-PA-related OA were determined from this study and from a meta-analysis. RESULTS: A total of 559 patients received intravenous rt-PA over a 12-year period. Five patients (two males) developed OA after rt-PA administration. The incidence of OA amongst these patients was 0.89% (95% confidence interval 0.29%-2.09%), which was lower than that obtained by meta-analysis (1.9%). Amongst pre-stroke anti-hypertensive medications, angiotensin-converting enzyme (ACE) inhibitors were found in this study to have the highest relative risk for rt-PA-related OA (17.1; 95% confidence interval 3.0-96.9). Meta-analysis also revealed that pre-stroke use of ACE inhibitors was associated with a high relative risk of OA after intravenous rt-PA (12.9; 95% confidence interval 4.5-37.0). CONCLUSIONS: The incidence of rt-PA-related OA in the Asian population is lower than that in the Caucasian population. Pre-stroke use of ACE inhibitors significantly increases the risk of this complication.


Subject(s)
Angioedema/chemically induced , Angiotensin-Converting Enzyme Inhibitors/therapeutic use , Brain Ischemia/drug therapy , Fibrinolytic Agents/adverse effects , Mouth Diseases/chemically induced , Registries/statistics & numerical data , Stroke/drug therapy , Thrombolytic Therapy/adverse effects , Tissue Plasminogen Activator/adverse effects , Aged , Aged, 80 and over , Angioedema/epidemiology , Brain Ischemia/epidemiology , Female , Fibrinolytic Agents/administration & dosage , Humans , Incidence , Male , Middle Aged , Mouth Diseases/epidemiology , Risk , Stroke/epidemiology , Taiwan/epidemiology , Thrombolytic Therapy/statistics & numerical data , Tissue Plasminogen Activator/administration & dosage , Tissue Plasminogen Activator/therapeutic use , Tongue Diseases/chemically induced , Tongue Diseases/epidemiology
3.
Eur J Neurol ; 20(8): 1128-34, 2013 Aug.
Article in English | MEDLINE | ID: mdl-22897602

ABSTRACT

BACKGROUND AND PURPOSE: Anticoagulant and antiplatelets for prevention of ischaemic stroke and cardiovascular diseases may increase the risk of intracerebral hemorrhage (ICH). This study aimed to investigate the influence of pre-ICH use of anticoagulant and antiplatelets on ICH patients. METHODS: Consecutive patients with acute spontaneous ICH registered in a single-center stroke registry during 2001 to 2010 were analyzed and categorized according to their pre-ICH use of warfarin (Group I), antiplatelets (Group II), or neither (Group III). Survival analysis and the Cox proportional hazard model were used to compare between the three groups and the predictors. RESULTS: Of 2021 ICH patients (male, 63.3%; mean age, 62.6 ± 14.4 years) included, there were 94 (4.7%) in Group I, 232 (11.4%) in Group II, and 1695 (83.9%) in Group III. Warfarin users had larger hematoma volume, more intraventricular extension, higher frequencies of lobar ICH, and higher case fatality than non-warfarin users (Groups II and III). The Cox proportional hazard model showed increased 6-month case fatality in pre-ICH warfarin users (adjusted hazard ratio 2.75, 95% confidence interval 2.04-3.72, P < 0.001), but not in pre-ICH antiplatelet users (adjusted hazard ratio 0.95, 95% confidence interval 0.72-1.26). CONCLUSIONS: Intracerebral hemorrhage patients with prior warfarin use, but not antiplatelet use, had significantly higher case fatality at 6 months.


Subject(s)
Anticoagulants/adverse effects , Cerebral Hemorrhage/mortality , Platelet Aggregation Inhibitors/adverse effects , Warfarin/adverse effects , Adult , Aged , Aged, 80 and over , Area Under Curve , Cerebral Hemorrhage/pathology , Female , Glasgow Coma Scale , Humans , Male , Middle Aged , Proportional Hazards Models , ROC Curve , Registries , Stroke/etiology , Stroke/mortality , Survival Analysis , Taiwan/epidemiology
4.
J Neurol Neurosurg Psychiatry ; 80(11): 1225-9, 2009 Nov.
Article in English | MEDLINE | ID: mdl-19332420

ABSTRACT

OBJECTIVES: Early diagnosis and management of intracranial dural arteriovenous fistulae (DAVF) may prevent the occurrence of stroke. This study aimed to identify the best carotid duplex sonography (CDS) parameters for screening DAVF. METHODS: 63 DAVF patients and 170 non-DAVF patients received both CDS and conventional angiography. The use of seven CDS haemodynamic parameter sets related to the resistance index (RI) of the external carotid artery (ECA) for the diagnosis of DAVF was validated and the applicability of the best CDS parameter set in 20 400 patients was tested. RESULTS: The CDS parameter set (ECA RI (cut-off point = 0.7) and internal carotid artery (ICA) to ECA RI ratio (cut-off point = 0.9)) had the highest specificity (99%) for diagnosis of DAVF with moderate sensitivity (51%). Location of the DAVF was a significant determinant of sensitivity of detection, which was 70% for non-cavernous DAVF and 0% for cavernous sinus DAVF (p<0.001). The above parameter set detected abnormality in 92 of 20 400 patients. These abnormalities included DAVF (n = 25), carotid stenosis (n = 32), vertebral artery stenosis (n = 7), intracranial arterial stenosis (n = 6), head and neck tumour (n = 3) and unknown aetiology (n = 19). CONCLUSION: Combined CDS parameters of ECA RI and ICA to ECA RI ratio can be used as a screening tool for the diagnosis of DAVF.


Subject(s)
Carotid Artery, External/diagnostic imaging , Central Nervous System Vascular Malformations/diagnosis , Ultrasonography, Doppler, Duplex/methods , Adult , Angiography , Carotid Artery, External/pathology , Central Nervous System Vascular Malformations/diagnostic imaging , Female , Humans , Male , Middle Aged , Sensitivity and Specificity
5.
J Med Eng Technol ; 27(2): 77-84, 2003.
Article in English | MEDLINE | ID: mdl-12745915

ABSTRACT

During the last decade, progressive achievements in haemodynamics have shown that radial artery pulse pressure can be used to estimate the vascular properties of the internal organs. Clinical experiments have shown that slow and regular respiration has a large effect on the heart rate variability (HRV). This phenomenon is called respiratory sinus arrhythmia (RSA). It is known that respiration-related oscillations in venous return cause oscillations in stroke volume and blood pressure. It also can be inferred from cardiac output that systemic blood pressure has a similar respiration-related cycle. Moreover we found that the fluctuations of harmonics of arterial pulse are consistent with the fluctuation of HRV. This means that the whole cardiovascular system (CVS) makes rapid adaptation during respiration, and the harmonic proportions of arterial pulse were modified during different breath rates. This result shows that the regular respiration also has a large effect upon Windkessel properties of CVS.


Subject(s)
Pulse , Respiration , Adult , Blood Pressure , Heart Rate , Humans , Male , Radial Artery
6.
Comput Biol Med ; 31(6): 471-80, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11604152

ABSTRACT

Time domain cross-correlation analysis of pre-filtered mean arterial blood pressure (MABP) and mean cerebral blood flow velocity (MCBFV) was applied to assess the cerebral autoregulation (CA). Beat-to-beat time series of spontaneous arterial blood pressure and cerebral blood flow velocity were obtained from 13 young normal volunteers with the Finapres device and the transcranial Doppler for periods of approximately 5 min in the supine position. Cross-correlation functions (CCFs) were estimated using a 64 beat wide moving window. Mean CCF patterns were obtained for each subject and for the entire population. The MABP and MCBFV signals were bandpass filtered in the very low-frequency range (VLF, 0.015-0.07 Hz), low-frequency range (LF, 0.07-0.15 Hz) and high-frequency range (HF, 0.15-0.40 Hz) before applying CCF for the purpose of studying the effect of different bandwidths on the resulting mean CCFs. Results revealed that the corresponding time lags of the peak values of the MABP-MCBFV CCFs increased significantly between the LF and HF frequency ranges (LF: -1.20+/-0.91 s, HF: -0.07+/-0.42 s,p < 0.001; paired sign test). The left-shift (negative lag) of the CCF peak between MABP and MCBFV is a result of the phase-lead property. The increasing time lag of the CCF peak indicated evidence of the autoregulatory disturbance. The CCF of pre-filtered spontaneous MABP and MCBFV could be a useful tool to estimate the CA dynamic response.


Subject(s)
Cerebrovascular Circulation/physiology , Adult , Blood Flow Velocity/physiology , Blood Pressure/physiology , Computers , Female , Homeostasis , Humans , Male , Models, Cardiovascular , Signal Processing, Computer-Assisted , Ultrasonography, Doppler, Transcranial
7.
Med Pediatr Oncol ; 35(6): 716-8, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11107154

ABSTRACT

BACKGROUND: Intrathecal antibody-based targeted therapies may have clinical potential for patients with leptomeningeal (LM) cancer. PROCEDURE: Five patients with GD2-positive LM tumors were injected with 1-2 mCi intra-Ommaya (131)I-3F8, a murine IgG3 antibody specific for GD2. Serial cerebrospinal fluid (CSF) and serum samples and SPECT imagings (4, 24, and 48 hr) were performed to predict radiation doses to the tumor and normal brain and blood prior to the administration of larger therapeutic doses. RESULTS: Side effects included self-limited fever, headache, and vomiting. Focal (131)I-3F8 uptake consistent with tumors was seen along the craniospinal axis in four patients. Calculated radiation dose to the CSF was 14.9-56 cGy/mCi and to blood and other organs outside the CNS less than 2 cGy/mCi. CONCLUSIONS: Intraventricular (131)I-3F8 successfully detected LM disease and resulted in a large favorable CSF/blood ratio. Intraventricular (131)I-3F8 may have clinical utility in the diagnosis and radioimmunotherapy of GD2-positive LM cancers. Med. Pediatr. Oncol. 35:716-718. 2000.


Subject(s)
Antibodies, Monoclonal , Antibodies/therapeutic use , Immunoglobulin G , Immunoglobulins/therapeutic use , Iodine Radioisotopes/therapeutic use , Meningeal Neoplasms/radiotherapy , Radioimmunotherapy , Antibodies, Monoclonal, Murine-Derived , Child , Child, Preschool , Humans , Infant , Middle Aged
8.
Chem Pharm Bull (Tokyo) ; 48(2): 288-9, 2000 Feb.
Article in English | MEDLINE | ID: mdl-10705522

ABSTRACT

An efficient one-pot procedure for the preparation of diazadioxime was described. Treatment of ketooximes with alkyldiamine followed by NaBH4 in dry ethanol afforded the corresponding d,l-diazadioximes in 56--74% yield without isolation of the intermediates.


Subject(s)
Diamines/chemical synthesis , Oximes/chemical synthesis , Radiopharmaceuticals/chemical synthesis , Indicators and Reagents , Ligands , Magnetic Resonance Spectroscopy , Spectrophotometry, Infrared
9.
Comput Biol Med ; 30(2): 71-88, 2000 Mar.
Article in English | MEDLINE | ID: mdl-10714443

ABSTRACT

A self-organizing classification system for the arterial pressure pulse based on the ART2 (adaptive resonance theory) network was developed. The system consists of a preprocessor and an ART2 recognition network. The preprocessor removes the arterial pressure pulse servo component signals from Finapres, detects the systolic pressure points and divides the acquired signals into minimal cardiac cycles. The ART2 network input is the minimal cardiac cycle detected by the preprocessor. The classification results can be used to assist physicians in evaluating the signs of abnormal and normal autonomic control and has shown its clinical applicability for the examination of the autonomic nervous system.


Subject(s)
Models, Cardiovascular , Neural Networks, Computer , Pattern Recognition, Automated , Pulse/classification , Artifacts , Diabetes Mellitus, Type 2/physiopathology , Humans , Photoplethysmography/instrumentation , Posture , Reference Values
10.
Catheter Cardiovasc Interv ; 49(1): 91-6, 2000 Jan.
Article in English | MEDLINE | ID: mdl-10627378

ABSTRACT

Tissue plasminogen activator (t-PA) was administered to three patients with newly developed intracardiac thrombi. Cases 1 and 2 developed right heart thrombi after radiofrequency ablation for atrioventricular nodal reentrant tachycardia and case 3 had tachycardia-related cardiomyopathy and a left ventricular thrombus. In all three patients, the intracardiac thrombi were successfully eliminated following t-PA therapy without major bleeding complications. These observations suggest that t-PA is effective in lysing new thrombus complicating radiofrequency ablation or heart failure and may be the therapy of choice in these conditions. Cathet. Cardiovasc. Intervent. 49:91-96, 2000.


Subject(s)
Fibrinolytic Agents/therapeutic use , Heart Diseases/drug therapy , Thrombolytic Therapy , Thrombosis/drug therapy , Tissue Plasminogen Activator/therapeutic use , Adult , Aged , Female , Heart Diseases/diagnostic imaging , Heart Diseases/etiology , Humans , Male , Thrombosis/diagnostic imaging , Thrombosis/etiology , Ultrasonography
11.
Bioorg Med Chem Lett ; 9(22): 3199-202, 1999 Nov 15.
Article in English | MEDLINE | ID: mdl-10576687

ABSTRACT

Tc-D,D- and TC-L,L-HMPAO were synthesized. The stability of Tc-D,D- and TC-L,L-HMPAO in vitro is similar to that of d,l-isomers by the spectrophotometric and three strips methods. Cerebral uptake (%D in brain) for the L,L-isomer is higer than the D,D- and d,l-isomer in rats. Delayed studies shows that T-L,L-HMPAO reveals less washout and reflects a higher cerebral deposition properties than the D,D- and d,l-isomer.


Subject(s)
Technetium Tc 99m Exametazime/chemical synthesis , Animals , Female , Isomerism , Rats , Rats, Wistar , Technetium Tc 99m Exametazime/chemistry , Technetium Tc 99m Exametazime/pharmacology
12.
J Am Coll Cardiol ; 33(2): 376-84, 1999 Feb.
Article in English | MEDLINE | ID: mdl-9973017

ABSTRACT

OBJECTIVES: The main objective of this study was to characterize the phenomenon of variation in the P-QRS relation during atrioventricular node reentry tachycardia. BACKGROUND: Variation of P-QRS relation during tachycardia has been observed occasionally in atrioventricular node reentry tachycardia. However, the incidence, the characteristics and the mechanisms of this phenomenon have not been investigated previously. METHODS: Retrospective analysis was performed in 311 consecutive patients with slow-fast form and 108 patients with atypical or multiple form of atrioventricular node reentry tachycardia to examine whether variation of P-QRS relation with changes in AH, HA and AH/HA (A = atria; H = His bundle) ratio occurred during tachycardia. RESULTS: A total of 28 patients, 8 with slow-fast and 20 with atypical or multiple tachycardias, were found to manifest this phenomenon. There were 6 males and 22 females, with an average age of 38+/-16 years. In 10 patients, this phenomenon occurred transiently following electrical induction of the tachycardia. In 15 patients, changes in AH, HA and AH/HA ratio were associated with the occurrence of Wenckebach or 2:1 block proximal to the His bundle (H) recording site without interruption of the tachycardia. In nine patients, three with nonsustained tachycardia and six after administration of adenosine triphosphate, this phenomenon was observed at the termination of the tachycardia. This phenomenon was usually accompanied by a mild lengthening of the tachycardia cycle length. CONCLUSIONS: Variation of P-QRS relation with or without block may occur during atrioventricular node reentry tachycardia, especially in atypical or multiple-form tachycardias. It was postulated that decremental conduction in the distal common pathway, which exists between the distal link of the reentry circuit and the H, is primarily responsible for this phenomenon.


Subject(s)
Electrocardiography , Heart Rate , Tachycardia, Atrioventricular Nodal Reentry/physiopathology , Adenosine Triphosphate/administration & dosage , Adenosine Triphosphate/therapeutic use , Adolescent , Adult , Aged , Aged, 80 and over , Atrioventricular Node/physiopathology , Bundle of His/physiopathology , Cardiac Pacing, Artificial , Child , Female , Follow-Up Studies , Humans , Injections, Intravenous , Male , Middle Aged , Retrospective Studies , Tachycardia, Atrioventricular Nodal Reentry/therapy
13.
J Clin Oncol ; 16(9): 3053-60, 1998 Sep.
Article in English | MEDLINE | ID: mdl-9738575

ABSTRACT

PURPOSE: To eradicate minimal residual disease with anti-G(D2) monoclonal antibody 3F8 in stage 4 neuroblastoma (NB) diagnosed at more than 1 year of age. PATIENTS AND METHODS: Thirty-four patients were treated with 3F8 at the end of chemotherapy. Most had either bone marrow (n=31) or distant bony metastases (n=29). Thirteen patients were treated at second or subsequent remission (group I) and 12 patients in this group had a history of progressive/persistent disease after bone marrow transplantation (BMT); 21 patients were treated in first remission following N6 chemotherapy (group II). RESULTS: Before 3F8 treatment, 23 patients were in complete remission CR, eight in very good partial remission (VGPR), one in partial remission (PR), and two had microscopic foci in marrow. Twenty-five had evidence of NB by at least one measurement of occult/minimal tumor (iodine 131[(131)I]-3F8 imaging, marrow immunocytology, or marrow reverse-transcriptase polymerase chain reaction [RT-PCR]). Acute self-limited toxicities of 3F8 treatment were severe pain, fever, urticaria, and reversible decreases in blood counts and serum complement levels. There was evidence of response by immunocytology (six of nine), by GAGE RT-PCR (seven of 12), and by (131)I-3F8 scans (six of six). Fourteen patients are alive and 13 (age 1.8 to 7.4 years at diagnosis) are progression-free (40 to 130 months from the initiation of 3F8 treatment) without further systemic therapy, none with late neurologic complications. A transient anti-mouse response or the completion of four 3F8 cycles was associated with significantly better survival. CONCLUSION: Despite high-risk nature of stage 4 NB, long-term remission without autologous (A)BMT can be achieved with 3F8 treatment. Its side effects were short-lived and manageable. The potential benefits of 3F8 in consolidating remission warrant further investigations.


Subject(s)
Antibodies, Monoclonal/therapeutic use , Gangliosides/immunology , Neoplasm, Residual/therapy , Neuroblastoma/therapy , Antibodies, Monoclonal/adverse effects , Antigens, Neoplasm/biosynthesis , Bone Marrow Neoplasms/secondary , Bone Neoplasms/secondary , Child , Child, Preschool , Combined Modality Therapy , Female , Humans , Immunotherapy , Infant , Male , Neoplasm Staging , Neuroblastoma/drug therapy , Neuroblastoma/radiotherapy , Treatment Outcome
14.
J Am Soc Echocardiogr ; 11(6): 668-72, 1998 Jun.
Article in English | MEDLINE | ID: mdl-9657407

ABSTRACT

Anomalous origin of the left coronary artery from the pulmonary artery in adults is difficult to identify reliably by transthoracic echocardiography (TTE). We describe a 32-year-old woman with this coronary anomaly mimicking a coronary artery fistula on conventional TTE study. This anomaly was suggested by multiplane transesophageal echocardiography (TEE) and subsequently confirmed by coronary angiography. Multiplane TEE thus may serve as a first-line diagnostic tool for detecting anomalous origin of coronary arteries.


Subject(s)
Coronary Vessel Anomalies/diagnostic imaging , Echocardiography, Transesophageal/methods , Pulmonary Artery/abnormalities , Adult , Female , Humans
15.
Am J Cardiol ; 81(4): 500-3, 1998 Feb 15.
Article in English | MEDLINE | ID: mdl-9485145

ABSTRACT

Clinical and electrophysiologic parameters were analyzed to define the factors potentially related to tachycardia recurrences in 79 patients undergoing successful radiofrequency ablation of idiopathic right or left ventricular tachycardia. It was found that the endocardial activation time at the successful ablation site was the only independent predictor of tachycardia recurrences.


Subject(s)
Catheter Ablation , Tachycardia, Ventricular/surgery , Adolescent , Adult , Aged , Aged, 80 and over , Child , Electrocardiography , Female , Follow-Up Studies , Humans , Male , Middle Aged , Recurrence , Tachycardia, Ventricular/physiopathology , Treatment Failure
16.
J Cardiovasc Electrophysiol ; 8(11): 1302-8, 1997 Nov.
Article in English | MEDLINE | ID: mdl-9395174

ABSTRACT

INTRODUCTION: Fast-intermediate form AV nodal reentry tachycardia (AVNRT) sometimes may mimic atrial tachycardia or atrial flutter and render the diagnosis difficult when the tachycardia rate is fast and AV block occurs during tachycardia. METHODS AND RESULTS: A 45-year-old woman with paroxysmal supraventricular tachycardia was referred to this institution. Initially, the tachycardia was thought to be an atrial tachycardia because of: (1) a short cycle length of the tachycardia with 2:1 and Wenckebach AV block; (2) a difference in the atrial activation sequence during tachycardia and during ventricular pacing; and (3) failure of burst ventricular pacing to affect the atrial rate and the atrial activation sequence during tachycardia. An accurate diagnosis of fast-intermediate form AVNRT was subsequently made based on the finding that the tachycardia was induced following delivery of a third ventricular extrastimulus, which showed a sequence of V-A-H and a change on atrial activation sequence of the induced beat. Successful radiofrequency ablation was achieved only after accurate diagnosis of the tachycardia was made. CONCLUSION: Fast-intermediate form AVNRT sometimes may masquerade as atrial tachycardia. Accurate diagnosis is mandatory for successful ablation therapy.


Subject(s)
Catheter Ablation , Tachycardia, Atrioventricular Nodal Reentry/physiopathology , Tachycardia/physiopathology , Electrocardiography , Female , Humans , Middle Aged , Tachycardia/surgery , Tachycardia, Atrioventricular Nodal Reentry/surgery
17.
J Am Coll Cardiol ; 30(5): 1339-45, 1997 Nov 01.
Article in English | MEDLINE | ID: mdl-9350937

ABSTRACT

OBJECTIVES: This study demonstrates that exercise-provocable tachycardia resembling right ventricular outflow tract tachycardia may originate from the anterobasal left ventricle. BACKGROUND: Reentry is the operative mechanism of idiopathic left ventricular tachycardia, with a QRS complex of right bundle branch block and superior axis that is responsive to verapamil but not adenosine. Whether some mechanism other than reentry is operative in some idiopathic left ventricular tachycardias is unclear. METHODS: In 4 of 53 consecutive patients with idiopathic left ventricular tachycardia, the tachycardia was sensitive to adenosine. These four patients were women 63, 61, 61 and 31 years old and were the subjects of the present study. RESULTS: In all four patients, spontaneous tachycardia was related to exercise or emotional stress. The tachycardia displayed atypical left (one patient) or right (three patients) bundle branch block with an inferior axis and marked variation in cycle length. An intravenous bolus of adenosine triphosphate (10 to 20 mg) terminated tachycardia in all four patients. Tachycardia was terminated or prevented in three patients given intravenous or oral verapamil. Atrial or ventricular incremental or extrastimulus testing induced tachycardia in all four patients (three with, one without isoproterenol infusion). Electrically induced tachycardia also demonstrated marked variation in cycle length, which ranged from 230 to 390 ms. Entrainment was not demonstrable with overdrive pacing from multiple sites. Endocardial mapping during tachycardia revealed that the earliest activations were registered 25, 40, 35 and 50 ms before onset of the QRS complex, respectively, from the anterior aspect of the left ventricle just below the mitral annulus, adjacent to the left ventricular outflow tract. High frequency Purkinje spikes were not recorded at this site. Radiofrequency current delivered to this site successfully ablated the tachycardia in three of the four patients. CONCLUSIONS: Exercise-provocable, catecholamine-mediated, verapamil-responsive, adenosine-sensitive ventricular tachycardia may arise from the anterobasal left ventricle adjacent to the outflow tract.


Subject(s)
Tachycardia, Ventricular/physiopathology , Adenosine/therapeutic use , Adult , Anti-Arrhythmia Agents/therapeutic use , Electrocardiography , Electrophysiology , Female , Humans , Middle Aged , Tachycardia, Ventricular/drug therapy
18.
J Am Coll Cardiol ; 30(4): 1024-31, 1997 Oct.
Article in English | MEDLINE | ID: mdl-9316534

ABSTRACT

OBJECTIVES: This study sought to assess the possibility of ablating verapamil-responsive idiopathic left ventricular tachycardia at a site distant from the tachycardia exit and thus to define the tachycardia circuit. BACKGROUND: The nature of the reentry circuit in idiopathic left ventricular tachycardia is unclear. If the circuit is of considerable size, then it should be possible to ablate the tachycardia at a site distant from the exit site. METHODS: Electrophysiologic studies and radiofrequency ablation were performed in 27 consecutive patients with verapamil-responsive idiopathic left ventricular tachycardia. In all 27 patients, the tachycardia exit site was defined as the site where the earliest Purkinje potential was recorded > or = 25 ms before the onset of the QRS complex during the tachycardia and where the pace map QRS complex resembled that during the tachycardia. A potential ablation site other than the exit site was then sought around the midseptum, proximal to the exit site. At such sites the tachycardia could be terminated transiently by pressure applied to the catheter tip, without induction of ventricular ectopic beats. RESULTS: The potential ablation site, other than the tachycardia exit site, was identified in seven male patients (mean [+/-SD] age 31 +/- 12 years, range 13 to 52). Application of the radiofrequency current at this site resulted in termination of the tachycardia within 1 to 5 s (mean 2.9 +/- 1.6), and successful ablation of the tachycardia was achieved in all seven patients (success rate 100%, 95% exact confidence interval 0.5898 to 1). The mean distance between the ablation site and the tachycardia exit site was 3.1 +/- 0.7 cm (range 2.0 to 4.0). A presystolic Purkinje spike was recorded 14 +/- 5 ms (range 8 to 20) before the onset of the QRS complex during the tachycardia. During the follow-up period of 24 +/- 11 months (range 12 to 39), there was no recurrence of tachycardia in these seven patients. CONCLUSIONS: Successful ablation of idiopathic left ventricular tachycardia can be achieved at sites away from the tachycardia exit site in some patients. This finding suggests that the reentry circuit is likely to be of considerable size, encompassing the middle, inferior and lower aspects of the left interventricular septum.


Subject(s)
Catheter Ablation/methods , Heart Conduction System/physiopathology , Heart Conduction System/surgery , Tachycardia, Ventricular/physiopathology , Tachycardia, Ventricular/surgery , Action Potentials , Adolescent , Adult , Catheter Ablation/standards , Electrocardiography , Female , Follow-Up Studies , Heart Conduction System/pathology , Heart Septum/pathology , Heart Ventricles/pathology , Humans , Male , Middle Aged , Recurrence , Tachycardia, Ventricular/pathology , Treatment Outcome
19.
Cathet Cardiovasc Diagn ; 42(1): 70-2, 1997 Sep.
Article in English | MEDLINE | ID: mdl-9286547

ABSTRACT

This report describes a patient who developed stenosis of coronary sinus and cardiac veins five years after application of electric shock currents to the posterior mitral annulus and posteroseptal region of the tricuspid annulus for ablation of a left posterior accessory pathway and a right posteroseptal accessory pathway. This is the first angiographic documentation of coronary sinus stenosis as a late complication of electric ablation of accessory pathway.


Subject(s)
Catheter Ablation , Coronary Disease/etiology , Postoperative Complications , Wolff-Parkinson-White Syndrome/surgery , Adult , Constriction, Pathologic , Coronary Angiography , Coronary Disease/diagnostic imaging , Heart Conduction System/abnormalities , Heart Conduction System/surgery , Humans , Male
20.
Eur J Nucl Med ; 24(6): 590-5, 1997 Jun.
Article in English | MEDLINE | ID: mdl-9169563

ABSTRACT

The search for an ideal radioisotope for systemic radiotherapy continues. As a generator-produced radioisotope emitting both beta and gamma rays and having a short physical half-life of 16.9 h, rhenium-188 is a very good potential candidate for systemic radiotherapy. In this study, we labeled hydroxyethylidene diphosphonate (HEDP) with 188Re and analyzed the biodistribution and bone uptake following intravenous injection in rats to assess its potential for clinical use. The rats were injected with approximately 14.8 MBq (0.4 mCi) 188Re-HEDP in a volume of 0.1 ml intravenously and then sacrificed at 1 h, 24 h, or 48 h (four rats at each time). Samples (about 0.1 g) of lung, liver, kidney, spleen, testis, muscle, stool, and bone (thoracic vertebra) were taken and weighed carefully. In addition, a 1-ml sample of blood was drawn from the heart and 1 ml of urine was taken from the urinary bladder immediately after killing. Tissue concentrations were calculated and expressed as percent injected dose per gram or per milliliter (% ID/g or ml). Bone lesions were created in the right tibial bone in three rabbits to calculate the lesion to normal uptake ratio (L/N ratio). The biodistribution data showed that the radioactivity in the bone tissue was as high as 1.877% ID/g at 1 h and that it climbed to 2.017% ID/g at 4 h. The activity level in the kidney was highest at 1 h but declined rapidly throughout the study. The radioactivities in the lung, liver, muscle, spleen, testis, blood, and stool were all lower than 0.3% ID/g at 1 h and also declined rapidly. The biological half-life in bone was the longest (60.86 h). In contrast, the biological half-lives in muscle and blood were short (2.99 h and 6.21 h respectively). The concentrations of radioactivity in muscle, spleen, testis, and stool were quite low throughout the study. Most of the radiotracer was excreted by the urinary system. The L/N ratio was 4.23+/-0.21 in rabbits injected with 188Re-HEDP and 4.25+/-0.23 in those injected with technetium-99m methylene diphosphonate. In conclusion, we would suggest that 188Re-HEDP is a very good potential candidate for the treatment of bone metastases because of the following characteristics: (1) it is generator produced; (2) it has a short half-life; (3) it emits gamma rays suitable for imaging; (4) there is highly selective uptake in the skeletal system and bone lesions; and (5) it has a low non-target uptake and rapid clearance in nonosseous tissue.


Subject(s)
Bone Neoplasms/radiotherapy , Bone Neoplasms/secondary , Etidronic Acid/therapeutic use , Radioisotopes/therapeutic use , Radiopharmaceuticals/therapeutic use , Rhenium/therapeutic use , Animals , Etidronic Acid/pharmacokinetics , Half-Life , Humans , Male , Rabbits , Radiation Dosage , Radioisotopes/pharmacokinetics , Radiopharmaceuticals/pharmacokinetics , Rats , Rats, Sprague-Dawley , Rhenium/pharmacokinetics , Tissue Distribution
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