BACKGROUNDThe aim of this study was to clarify the electrocardiographic characteristics of repetitive monomorphic ventricular tachycardia (RMVT) originating from the left ventricular outflow tract, and to describe the results of treatment with radiofrequency catheter ablation (RFCA).

METHODSRoutine 12-lead surface electrocardiography and electrophysiological studies were performed on 11 RMVT patients with no organic heart disease, who were subsequently treated with RFCA directed at targets identified by pace mapping.

RESULTSThe surface electrocardiogram QRS characteristics of RMVT included an atypical left bundle branch block and right axis deviation, with a low amplitude "rs" or "rS" pattern in lead I, an "rS" or "RS" pattern in V1, and a precordial R wave transition zone in V2 or V3. In 1 patient, a small S wave was observed in V5. Using pace mapping techniques, we selected the left coronary cusp as the ablation target. RMVT was eliminated in all 11 patients immediately after radiofrequency energy delivered. During a follow-up of 13 +/- 7 months, RMVT recurred in only 1 patient.

CONCLUSIONRMVT originating from the left ventricular outflow tract has specific electrocardiographic characteristics, and can be successfully and safely cured using RFCA directed at the left coronary cusp.

Adolescent ; Adult ; Catheter Ablation ; Electrocardiography ; Female ; Humans ; Male ; Middle Aged ; Tachycardia, Ventricular ; physiopathology ; surgery ; Treatment Outcome

OBJECTIVETo investigate the cyto-genotoxicity of cigarette smoke condensates (CSCs) in human peripheral blood lymphocytes with different assays in vitro.

METHODSHuman lymphocytes were exposed to particle matter of cigarette smoke combined with or without S9 mixtures at doses of 25, 50, 75, 100 and 125 microg/ml for 3 h. The cytotoxicity induced by CSCs was detected by CCK-8 assay. The DNA damage, DNA repair (repair time: 30, 60, 90, 120 and 240 min, respectively) and the somatic cell mutations induced by 75 microg/ml CSCs were measured by comet assay, hprt gene and TCR gene mutation tests, respectively.

RESULTSCCK-8 assay indicated that the cell viability decreased with CSCs doses. At the doses of 100, 125 microg/ml, the cell viability of CSCs +S9 group was significantly higher than that of CSCs -S9 group (P < 0.05, P < 0.01). In comet assay, DNA damage significantly increased in a dose-dependent manner, as compared with controls (P < 0.01). Moreover, there was significant difference between -S9 group and +S9 group (P < 0.05, P < 0.01). The Mf-TCR at each dose group was significantly higher than that of controls (P < 0.05, P < 0.01). The Mf-hprt at high-dose groups were significantly higher than that of controls (P < 0.01), and significant difference of Mf-TCR and Mf-hprt at high doses of CSCs between -S9 group and +S9 group (P < 0.05, P < 0.01). The DNA damage induced by CSCs +S9 or CSCs -S9 could be repaired, but DNA repair speed was different between -S9 group and +S9 group (P < 0.05, P < 0.01).

CONCLUSIONCSCs may induce cyto-genotoxicity in human peripheral blood lymphocytes in vitro, but S9 mix could reduce the toxicity of CSCs and impact DNA repair speed.

Cells, Cultured ; Comet Assay ; DNA Damage ; drug effects ; DNA Repair ; drug effects ; Humans ; Lymphocytes ; drug effects ; Male ; Mutation ; Tobacco Smoke Pollution ; adverse effects ; Young Adult

OBJECTIVETo investigate the feasibility and effectiveness of radiofrequency catheter ablation (RFCA) to treat per-manent atrial fibrillation (AF) under the guidance of Carto-Merge technique.

METHODSFifteen male patients with permanent AF underwent RFCA under the guidance of Carto-Merge technique. The mean age was 54.00 +/- 10.44 years, and duration of AF was 23.66 +/- 14.93 months. Cardiac magnetic resonance angiography (MRA) was performed to obtain pre-procedural three-dimensional (3D) images on the anatomy of left atrium (LA) and pulmonary veins (PVs) before RFCA procedure. Then the electroanatomical map was integrated with 3D images of MRA to form Carto-Merge map that guided step-by-step ablation strategy of permanent AF. Circumferential PV ablation was performed first until complete PVs electric isolation confirmed by Lasso catheter. If AF was not terminated, lesion lines on roof of LA, mitral isthmus, and tricuspid isthmus were produced.

RESULTSThe episodes of AF were terminated during RFCA in 2 patients, by direct current cardioversion in the remaining 13 patients. Transient AF occurred in 2 patients after ablation on 1st day and 1st week respectively, AF terminated spontaneously not long after taking metoprolol. One patient developed persistent atrial flutter (AFL) in 2 months after procedure and AFL was eliminated by the second ablation. Persistent AF recurred on 1st day, 1st and 5th week respectively in 3 patients, and did not terminate after 3 months even though amiodarone was given. The remaining 12 patients were all free of AF during 2-11 months of follow-up. The recent success rate for RFCA of permanent AF was 80%.

CONCLUSIONSCarto-Merge technique can effectively guide RFCA of permanent AF. When combined with single Lasso mapping, it can simplify the mapping, lower expenses, and enhance the success rate of RFCA of permanent AF.

Adult ; Atrial Fibrillation ; physiopathology ; radiotherapy ; Catheters, Indwelling ; Humans ; Male ; Middle Aged ; Radio Waves

BACKGROUNDTypical accessory pathways (APs) of Wolf-Parkinson-White syndrome have been widely discussed in recent decades. However, the characteristics of the special AP, Mahaim fibre, are not so clear. It is known that these fibres have antegrade conduction only, long conduction time, decremental node-like conduction and automaticity properties. This study was to elucidate the automaticity of Mahaim fibre and its response to effective ablation.

METHODSThirteen patients with Mahaim fibre (ten atrioventricular and three atriofascicular accessory pathways) were subjected to electrophysiological study and radiofrequency ablation via catheter. The incidence and characteristics of anautomatic rhythm originating from Mahaim fibre were observed during the whole procedure, especially during radiofrequency current delivery.

RESULTSRepetitive and short-run automatic rhythm (rate: 65-72 beats per minute), with a QRS morphology similar to that of clinical pre-excited atrioventricular re-entrant tachycardia (AVRT), occurred in two patients during sinus rhythm. Conduction via Mahaim fibre was successfully eliminated by radiofrequency current. Fourteen applications of RF were associated with irregularly accelerated automatic tachycardia of Mahaim fibre (with a sensitivity of 78%), lasting for 1.2-14 seconds. However, such automatic tachycardia of Mahaim fibre did not occur during 54 failed applications of radiofrequency current.

CONCLUSIONSMahaim fibre has the function of automaticity. The accelerated automatic tachycardia of Mahaim fibre occur red during radiofrequency catheter ablation can be used as a predictor for successful procedure.

Adolescent ; Adult ; Catheter Ablation ; Child ; Female ; Humans ; Male ; Middle Aged ; Pre-Excitation, Mahaim-Type ; physiopathology ; surgery ; Tachycardia, Atrioventricular Nodal Reentry ; physiopathology ; surgery

OBJECTIVETo investigate the effectiveness and advantages of the Carto merge technique in guiding radiofrequency catheter ablation (RFCA) of permanent atrial fibrillation (AF).

METHODSA total of 15 patients with permanent AF underwent RFCA under guidance of the Carto merge technique. The virtual electroanatomical map of the left atrium (LA) and pulmonary veins (PVs) were reconstructed with Carto system during the procedure. Then the electroanatomical map was integrated with 3-D images of cardiac magnetic resonance angiography to form Carto merge map. Circumferential pulmonary vein ablation was performed first until complete PVs electric isolation confirmed by lasso catheter. If AF was not terminated, lesion lines on roof of LA, mitral isthmus, and tricuspid isthmus were produced. Finally direct current (DC) cardioversion were given if sinus rhythm did not return.

RESULTSAF were terminated spontaneously during RFCA in 2 patients, and by DC cardioversion in the remaining 13 patients. Persistent AF recurred on 24 hours, first week, and 5th week, respectively in three patients. The remaining 12 patients were all free of AF during follow-up (1-10 months). The success rate was 80% in the study.

CONCLUSIONSCarto merge technique can effectively guide RFCA of permanent AF. When combined with single Lasso mapping, it can simplify the mapping and enhance the success rate of RFCA of permanent AF.

Atrial Fibrillation ; surgery ; Catheter Ablation ; methods ; Humans

OBJECTIVETo explore the sonographic characteristics of intraveous leiomyomatosis (IVL) with intracardiac extension and improve its diagnosis.

METHODSThe clinical and sonographic data of 13 female patients with pathologically confirmed IVL with intracardiac extension who were treated in our hospital between 2002 and 2012 were retrospectively analyzed. These patients aged 44 years old (range: 38-49 years), and 10 of them were first-episode patients and the remaining 3 were recurrent patients. Eight patients had a history of hysterectomy for leiomyoma.

RESULTSThe first-episode symptoms included exertional chest tightness and shortness of breath (n=5), abdominal distention and edema of low extermity (n=4), exertional palpitation of cardiac origin (n=3), and menorrhagia (n=1). Ultrasonography showed that all patients had isoechoic or hypoechoic tumors extended through the inferior vena cava into right heart chambers (62% in right atrium alone and 38% in right ventricle and atrium). Nine masses in right heart chamber (69.2%) were oval and 4 (30.8%) were serpentine, which were all with well-demarcated borders and most (80%) with heteroechogenic texture. Ten patients had hypoechoic or mixed echoic tumors in pelvic cavity or uterus, and 6 of them had abundant blood flow.

CONCLUSIONSIVL with intracardiac extension has certain sonographic characteristics. Ultrasonography is a valuable tool in the diagnosis of IVL with intracardiac extension.

Adult ; Female ; Humans ; Leiomyomatosis ; diagnostic imaging ; pathology ; Middle Aged ; Myocardium ; pathology ; Retrospective Studies ; Ultrasonography ; Vascular Neoplasms ; diagnostic imaging ; pathology

OBJECTIVETo study possible correlation between matrix metalloproteinases (MMPs) activities and myocardial injury after asphyxia in neonatal Wistar rats.

METHODSixty neonatal Wistar rats (7 to 10 days old) were randomly divided into four groups: control group (group D); asphyxia groups A, B and C (1 day, 7 days, 14 days after asphyxia), every group had 15 rats. In the asphyxia groups, animal model was produced by normobaric asphyxia. Groups A, B and C were sacrificed on days 1, 7 and 14 days after asphyxia, and group D rats were sacrificed on the 7 th day. Then the heart blood was taken to tested the serum cTnI. The myocardial MMPs-3 and 9 activity was measured by using immunohistochemical assay. Histological sections of the hearts were stained with hematoxylin-eosin and myocardial histopathological scores were determined under an optical microscope. The amount of myocardial collagen was measured by means of chloramines T.

RESULTScTnI was significantly higher in group A (0.3680 +/- 0.40 ng/ml) than group D (0.0783 +/- 0.06 ng/ml) (P < 0.05), and was lower in group B (0.1889 +/- 0.15 ng/ml) but still significantly different from that of group D (P < 0.05), and declined to the normal level in group C (0.1338 +/- 0.07 ng/ml), but the difference between groups C and D was not significant (P > 0.05). Myocardial tissue MMPs-3 activity was transiently high in group A (0.1847 +/- 0.04), higher in group B (0.2780 +/- 0.05) as compared to group D (0.1213 +/- 0.03) (P < 0.05 for all). The activity of MMPs-3 increased earlier than that of MMPs-9. The amount of myocardial collagen of group B (38.94 +/- 0.67) and C (40.69 +/- 0.75) was significantly greater than that of group D (P < 0.05). Myoardial tissue MMPs-3 and MMPs-9 positively correlated with myocardial histopathological scores (r = 0.669, 0.667, P < 0.05) and myocardial collagen (r = 0.482, 0.679, P < 0.05).

CONCLUSIONSIn rats with asphyxia, there was an excess activation of myocardial MMPs-3 and MMPs-9 activities and secondary to which, the quantity of myocardial collagen increased. The injuries of myocardium may be closely associated with myocardial tissue MMPs. MMPs may be used to evaluate the severity of myocardial interstitial damage.

Animals ; Asphyxia ; metabolism ; pathology ; Collagen ; metabolism ; Disease Models, Animal ; Matrix Metalloproteinase 3 ; metabolism ; Matrix Metalloproteinase 9 ; metabolism ; Myocardium ; metabolism ; pathology ; Rats ; Rats, Wistar ; Troponin I ; blood

OBJECTIVETo evaluate the effect of mitochondrial DNA(mtDNA) secondary mutations, haplotypes, GJB2 gene mutations on phenotype of 1494C>T mutation, and to study the molecular pathogenic mechanism of maternally transmitted aminoglycoside-induced and nonsyndromic hearing loss.

METHODSTwo Chinese Han pedigrees of maternally transmitted aminoglycoside induced and nonsyndromic hearing loss were collected. The two probands and their family members underwent clinical, genetic and molecular evaluations including audiological examinations and mutational analysis of mitochondrial genome and GJB2 gene.

RESULTSClinical evaluation revealed wide range of severity, age-at-onset and audiometric configuration of hearing impairment in matrilineal relatives in both families, for which the penetrance of hearing loss was respectively 42.9% and 28.6% when aminoglycoside-induced deafness was included. When the effect of aminoglycosides was excluded, the penetrances of hearing loss were 14.3% and 14.3%. Sequence analysis of mitochondrial genomes identified a known 12S rRNA 1494C>T mutation, in addition with distinct sets of mtDNA polymorphisms belonging to Eastern Asian haplogroups C4a1a and B4b1c, respectively.

CONCLUSIONMitochondrial 12S rRNA 1494C>T mutation probably underlie the deafness in both families. Lack of significant mutation in the GJB2 gene ruled out involvement of GJB2 in the phenotypic expression. However, aminoglycosides and other nuclear modifier genes may still modify the phenotype of the 1494C>T mutation in these families. The B4b1c is a newly identified haplogroup in aminoglycoside-induced and nonsyndromic hearing loss family carrying the 1494C>T mutation. The 1494C>T mutation seems to have occurred sporadically through evolution.

Adult ; Aminoglycosides ; adverse effects ; Asian Continental Ancestry Group ; genetics ; Base Sequence ; Connexin 26 ; Connexins ; genetics ; DNA, Mitochondrial ; genetics ; Genetic Predisposition to Disease ; Haplotypes ; Hearing Loss ; chemically induced ; genetics ; Humans ; Male ; Molecular Sequence Data ; Mutation ; Pedigree ; Phenotype ; RNA, Ribosomal ; genetics ; Young Adult

Objective To investigate the influence of nerve growth factor (NGF) on the level of plasma creatine kinase BB (CK-BB) and its clinical effect in patients with severe craniocerebral trauma. Methods Eighty patients with severe craniocerebral trauma (GCS≤8) were randomly assigned to NGF-treated (n=40) and control (n=40) groups. Conventional therapy was performed on these patients and NGF was added into the NGF-treated group. The level of plasma CK-BB in these patients was measured; the clinical prognosis of the patients was evaluated based on the GOS scores 6 months after severe craniocerebral trauma; the condition of regained consciousness was compared between the 2 groups. Results Plasma CK-BB in the NGF-treated group was significantly lower than that in the control group (P<0.05); the recovery rate in the NGF-treated group (24/40) was significantly higher than that in the control group (11/40); the consciousness regained within i month was found in 32 patients in the NGF-treated group but only 18 of that was noted in the control group (P<0.05); NGF-treated group (12.43±6.25) showed a significantly shorter time that consciousness was regained as compared with the control group (15.96±7.58). Conclusion NGF can decrease the level of plasma CK-BB, shorten coma time and improve life quality in patients with severe craniocerebral trauma. Application ofNGF, a safe and effective treatment method, provides a new potential therapeutic strategy for patients with CNS injury.

BACKGROUNDVerapamil-sensitive, idiopathic left ventricular tachycardia (ILVT) with right bundle branch block configuration and left-axis deviation is known to be due to re-entry mechanism but the exact nature of reentrant circuit in ILVT is not fully elucidated. Radiofrequency (RF) ablation was applied during ventricular tachycardia (VT) and termination of the VT or abolishing the inducibility of the tachycardia was used as an endpoint for successful RF. In this study, the left posterior fascicular block in surface electrocardiogram (ECG) was used as a new endpoint of ablation to cure ILVT.

METHODSElectrophysiological studies and radiofrequency ablation were performed in 39 consecutive patients [30 men, 9 women; age ranging from 10 to 64 years, mean (29 +/- 16) years] with verapamil-sensitive ILVT and structurally normal hearts. VT could be terminated by the intravenous administration of verapamil in all patients. The target site was the midseptum of LV where the earliest Purkinje potentials were recorded during VT. RF current was applied to the target site with or without late diastolic potential (LDP) during sinus rhythm in 37 patients and during VT in 2 patients to meet the ablation endpoint: the left posterior fascicular block in the surface ECG.

RESULTSThirty-seven patients with ILVT had been treated by RF ablation during sinus rhythm and two had been treated during VT. All of them met the endpoint of the left posterior fascicular block. Thirty-eight cases were symptom-free without medications during the follow-up period (range from 3 to 95 months, median 17 months). One patient developed a clinical recurrence and the left posterior fascicular block in surface ECG disappeared. The patient received another treatment. The endpoint was met and the procedure was successful.

CONCLUSIONSThe left posterior fascicular block in surface ECG used as an endpoint of RF ablation to treat ILVT is effective. It is important especially in those patients whose VT can not be induced or the inducible condition is unstable. The effective endpoint implied that the left posterior fascicle might be a critical part of the re-entrant circuit.

Adolescent ; Adult ; Catheter Ablation ; methods ; Child ; Diastole ; Electrocardiography ; Female ; Humans ; Male ; Middle Aged ; Tachycardia, Ventricular ; physiopathology ; surgery ; Verapamil ; therapeutic use