Catheter ablation of premature ventricular complexes associated with false tendons: A case report.

BACKGROUND: False tendon is a common intraventricular anatomical variation. It refers to a fibroid or fibromuscular structure that exists in the ventricle besides the normal connection of papillary muscle and mitral or tricuspid valve. A large number of clinical studies have suggested that there is a significant correlation between false tendons and premature ventricular complexes. However, few studies have verified this correlation during radiofrequency catheter ablation of premature ventricular complexes. CASE SUMMARY: A 45-year-old male was admitted to receive radiofrequency ablation for symptomatic premature ventricular complexes. A three-dimensional model of the left ventricle was established by intracardiac echocardiography using the CartoSoundTM mapping system. In addition to the left anterior papillary muscle, the posterior papillary muscle was mapped. False tendons were found at the base of the interventricular septum, and the other end was connected to the left ventricular free wall near the apex. An irrigated touch force catheter was advanced into the left ventricle via the retrograde approach. The earliest activation site was marked at the interventricular septum attachment of the false tendons and was successfully ablated. CONCLUSION: This case verified that false tendons can cause premature ventricular complexes and may be cured by radiofrequency ablation guided by intracardiac echocardiography with the CartoSoundTM system.

[Timing of positive head-up tilt test for patients with suspected vasovagal syncope].

OBJECTIVE: To investigate the time course of positive head-up tilt test (HUTT) for patients with suspected vasovagal syncope. METHODS: Consecutive patients referred to the syncope unit of our center for recurrent unexplained syncope were included. The HUTT consisted of a 30 minute passive basic phase and a 20 minute sublingual nitroglycerin provocation phase if syncope did not develop during the passive phase. RESULTS: Positive HUTT was observed in 427 out of 773 consecutive patients (55.2%) patients including 43 patients (10.1%) during the passive basic phase and 384 patients (89.9%) during the nitroglycerin provocation phase. During the basic phase, the positive Hutt developed at 7.5 minute (n = 2) and peaked at 22.5th minute (20.9%, n = 9) and then decreased gradually. Most positive reactions (93.0%, n = 40) occurred between the 10 and 25 minutes during the basic phase. During the nitroglycerin provocation phase, the percentage of positive reactions increased rapidly after sublingual nitroglycerin, peaked at the 10th minute (35.7%, n = 137) and decreased thereafter. Most positive reactions (96.1%, n = 369) occurred within the first 15 minutes of provocation phase. CONCLUSION: The appropriate duration for HUTT test could be modified to a 25 minutes passive basic phase plus 15 minutes nitroglycerin provocation phase.

Clinical study of 39 Chinese patients with arrhythmogenic right ventricular dysplasia/cardiomyopathy.

BACKGROUND: There are few studies on the clinical profile of Chinese patients with arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C). The purpose of this study was to describe the clinical characteristics of ARVD/C patients from China, particularly to define the features of electrocardiograph and treatment outcomes. METHODS: Thirty-nine patients hospitalized in Fu Wai Cardiovascular Hospital from 1998 to 2006 were included. The data were obtained from the medical archive and the follow-up records. RESULTS: Of these patients 33 were male and 6 female (age at the first presentation was (34.9 +/- 9.8) years). The most common symptoms were palpitation (62%) and syncope (44%). Right precordial QRSd >or= 110 ms was detected in 69% of the patients, epsilon wave in 59%, and a ratio of QRSd in V(1) + V(2) + V(3)/V(4) + V(5) + V(6) >or= 1.2 in 82%. The most frequent features of electrocardiogram in patients without right bundle-branch block were T-wave inversions and S-wave upstroke in V(1)-V(3) >or= 55 ms (96% and 90% of 28 patients, respectively). Radiofrequency catheter ablation (RFCA) for ventricular tachycardia (VT) was successful in 15 (68%) of 22 patients. The recurrence rate of VT was 46% (7/15) during the follow-up of (16.7 +/- 11.2) months. Seven patients had cardioverter/defibrillator (ICD) implanted plus drug therapy and 17 patients took antiarrhythmic drugs alone. During the follow-up of (35.6 +/- 19.0) months, all patients with ICD implanted received at least one appropriate ICD shock. One patient died of ventricular fibrillation suddenly and one patient underwent heart transplantation for progressive biventricular heart failure during the drug therapy alone. CONCLUSIONS: This study demonstrated the clinical and ECG features of the 39 ARVD/C Chinese patients. ICD provided life-saving protection by effectively terminating malignant arrhythmias, and the high recurrence of VT was the major problem of RFCA therapy.

Radiofrequency catheter ablation of permanent atrial fibrillation under guidance of carto-merge technique.

OBJECTIVE: To investigate the feasibility and effectiveness of radiofrequency catheter ablation (RFCA) to treat per-manent atrial fibrillation (AF) under the guidance of Carto-Merge technique. METHODS: Fifteen 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. RESULTS: The 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%. CONCLUSIONS: Carto-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.

[Clinical and ECG features of arrhythmogenic right ventricular cardiomyopathy: a retrospective analysis of 31 cases].

OBJECTIVE: To retrospectively analyze the clinical and electrocardiographic features of patients with arrhythmogenic right ventricular cardiomyopathy (ARVC). METHODS: The clinical, electrocardiographic features and the efficacy of various therapies were analyzed in 31 patients (27 males) diagnosed as ARVC according to the criteria established by European Society of Cardiology. RESULTS: The averaged age when the ARVC was first diagnosed was (34.7 +/- 9.4) years (19 - 58 years), palpitation was present in 28 patients (90.3%) and syncope in 13 patients (41.9%), a family history of sudden death was present in 1 patient. Dilatated right ventricle was documented in 29 patients by echocardiography and (or) magnetic resonance imaging (MRI), 2 of them with dilated left ventricles. ECG changes included: T wave inversion, mostly seen in precordial leads (100%); epsilon (epsilon) wave (54.8%); QRS duration >or= 110 ms in V(1) to V(3) (83.9%); reduced extremity amplitude (41.9%); the first degree of AV block (22.6%); sustained VT (100%) including 15 monomorphic VT (48.4%) and 16 polymorphic VT (51.6%). The mean values of QRS duration in leads of V(1 - 3) [(120.8 +/- 13.7) ms] was significantly longer than that in V(4 - 6) [(99.4 +/- 13.7) ms, P < 0.05]. Fourteen patients underwent radiofrequency catheter ablation (RFCA) with an immediate success rate of 78.6% (11/14). During follow up (18.3 +/- 10.2) months, VT reoccurred in 6 patients (54.5%). The remaining 17 patients were treated with conventional medications, 7 of them were medicated under implanted cardioverter defibrillator (ICD). During the follow-up (35.6 +/- 19.0) months, VT reoccurred in 11 patients (64.7%) and one patient died suddenly. CONCLUSIONS: ARVC patients developed symptoms at mid-30s with significant ECG changes including appearance of an epsilon wave, T wave inversion and QRS duration >or= 110 ms in leads of V(1 - 3). The long term therapy efficacy was not satisfactory both for RFCA and conventional medications and ICD implantation should be recommended to patients with ARVC.