Ventricular premature complexes (VPCs) are known to be one of the most benign cardiac arrhythmias when they occur in structurally normal hearts. We experienced a 32-year old man who presented with dyspnea, palpitations and very frequent VPCs (31% of the total heart beats). Echocardiography revealed a dilated left ventricle (LV 66 mm at end-diastole and 57 mm at end-systole) and a decreased ejection fraction (34%). Very frequent VPCs had been detected 10 years previously and he underwent a failed radiofrequency catheter ablation (RFCA) procedure at that time. The patient had been treated with heart failure medications including betablockers, ACE inhibitors and spironolactone for the two most recent years. Six months after we eliminated these VPCs with a second RFCA procedure, the heart returned to normal function and size. Long standing and very frequent VPCs could be the cause of left ventricular dysfunction in a subset of patients who suffer with dilated cardiomyopathy, and RFCA should be the choice of therapy for these patients.
Ventricular Premature Complexes/*complications ; Tachycardia, Ventricular/*etiology/therapy ; Male ; Humans ; *Catheter Ablation ; Cardiomyopathies/*etiology/therapy ; Adult

BACKGROUNDCardiac resynchronization therapy (CRT) could improve heart function, symptom status, quality of life and reduce hospitalization and mortality in patients with severe heart failure (HF) with optimal medical management. However, the possible adverse effects of CRT are often ignored by clinicians.

METHODA retrospective analysis of CRT over a 6-year period was made in a single cardiac center.

RESULTSFifty-four patients were treated with CRT(D) device, aged (57 ± 11) years, with left ventricular ejection fraction of (32.1 ± 9.8)%, of which 4 (7%) developed ventricular tachycardia/ventricular fibrillation (VT/VF) or junctional tachycardia after operation. Except for one with frequent ventricular premature beat before operation, the others had no previous history of ventricular arrhythmia. Of the 4 patients, 3 had dilated cardiomyopathy and 1 had ischemic cardiomyopathy, and tachycardia occurred within 3 days after operation. Sustained, refractory VT and subsequent VF occurred in one patient, frequent nonsustained VT in two patients and nonparoxysmal atrioventricular junctional tachycardia in one patient. VT was managed by amiodarone in two patients, amiodarone together with beta-blocker in one patient, and junctional tachycardia was terminated by overdrive pacing. During over 12-month follow-up, except for one patient's death due to refractory heart and respiratory failure in hospital, the others remain alive and arrhythmia-free.

CONCLUSIONSNew-onset VT/VF or junctional tachycardia may occur in a minority of patients with or without prior history of tachycardia after biventricular pacing. Arrhythmia can be managed by conventional therapy, but may require temporary discontinuation of pacing. More observational studies should be performed to determine the potential proarrhythmic effect of CRT.

Cardiac Resynchronization Therapy ; adverse effects ; Humans ; Perioperative Period ; Retrospective Studies ; Tachycardia, Ventricular ; etiology ; Ventricular Fibrillation ; etiology

Animals ; Cardiac Resynchronization Therapy ; adverse effects ; Dogs ; Heart Failure ; therapy ; Tachycardia, Ventricular ; etiology

OBJECTIVETo observe the ECG and electrophysiological characteristic of patients with idiopathic ventricular tachycardia (VT) and premature ventricular contraction (PVC) originating from left (LVOT) and right (RVOT) ventricular outflow tracts and assess the clinical effect of radio frequency catheter ablation (RFCA) on these patients.

METHODSRFCA was performed in 58 patients (10 with VT and 48 with PVC, 5 patients with VT from RVOT under the guidance of non-contact mapping system Ensite3000). VT or PVC originated from LVOT in 15 patients (12 out of 15 from left sinus of Valsalva) and RVOT in 43 patients.

RESULTS(1) R wave in II, III, aVF leads was the common characteristics of VT or PVC originated from LVOT and RVOT and difference in wave duration index and R/S-wave amplitude ratio in V(1) or V(2) could be used to define VT and PVC originated from LVOT or RVOT. (2) Ablation was successful in 55 out of 58 patients (9 patients with the 2nd ablation, evaluated as arrhythmia-free at 3 months post ablation without medication) and failed in 3 patients. One patient developed pericardial tamponade during ablation and recovered without complication after related treatments.

CONCLUSIONSRFCA is an effective, safe and curative therapy for VT or PVC originated from LVOT and RVOT. Non-contact mapping system (Ensite3000) is a safe and reliable tool to guide mapping and ablation in patients with complex VT and unstable hemodynamics.

Adolescent ; Adult ; Aged ; Catheter Ablation ; Female ; Humans ; Male ; Middle Aged ; Tachycardia, Ventricular ; etiology ; therapy ; Ventricular Outflow Obstruction ; complications ; Ventricular Premature Complexes ; etiology ; therapy ; Young Adult

Aged ; Catheter Ablation ; adverse effects ; Heart Injuries ; etiology ; Humans ; Male ; Tachycardia, Ventricular ; therapy

OBJECTIVETo study the application of abnormal electrophysiological substrate mapping for guiding ablation of ventricular tachycardias in arrhythmogenic right ventricular cardiomyopathy (ARVC-VTs) using a non-contact mapping system.

METHODSDynamic substrate mapping was performed in three male ARVC patients during sinus rhythm. The sites of the earliest activation, exit point and activation sequence were mapped for each induced VT.

RESULTSThree different patterns of substrates were determined in 3 patients, which located in right ventricular outflow tract, anterior right ventricular wall, and anterolateral right ventricular wall, respectively. Five different clinical VTs [mean CL (348 +/- 65) ms] were induced. Of 5 VTs, three were originated from substrate or boundary of substrate, and two had a remote origin. One VT conducted through the substrate. Linear ablations were created between the sites of the earliest ventricular activation and the VT exit point, or across the critical isthmus. The five clinical VTs were successfully ablated. There were no VT recurrences during 20 months of follow-up.

CONCLUSIONSDefining the abnormal electrophysiologic VT substrates is useful for understanding the mechanisms of ARVC-VTs and determining an ablation strategy. Linear ablation across a critical isthmus or between the earliest activation and the exit point can effectively cure these arrhythmias.

Adult ; Arrhythmogenic Right Ventricular Dysplasia ; etiology ; physiopathology ; therapy ; Catheter Ablation ; methods ; Electrophysiologic Techniques, Cardiac ; Humans ; Male ; Tachycardia, Ventricular ; complications ; physiopathology ; therapy

We describe a 51-yr-old man presenting with syncope due to torsade de pointes. The torsade de pointes was refractory to conventional medical therapy, including infusion of isoproterenol, MgSO4, potassium, lidocaine, and amiodarone. His past history, physical findings, and hormone study confirmed that QT prolongation was caused by anterior hypopituitarism that developed as a sequela of hemorrhagic fever with renal syndrome. The long QT interval with deep inverted T wave was completely normalized 4 weeks after starting steroid and thyroid hormone replacement. Hormonal disorders should be considered as a cause of torsade de pointes, because this life-threatening arrhythmia can be treated by replacing the missing hormone.
Hemorrhagic Fever with Renal Syndrome/*complications/physiopathology ; Hormone Replacement Therapy ; Human ; Hypopituitarism/drug therapy/*etiology/physiopathology ; Male ; Middle Age ; Tachycardia, Ventricular ; Torsades de Pointes/drug therapy/*etiology/physiopathology

No abstract available.
Aged ; Cardiovascular Agents/therapeutic use ; Echocardiography ; Electrocardiography ; Female ; Humans ; Stress, Psychological/*complications ; Tachycardia, Ventricular/diagnosis/drug therapy/*etiology ; Takotsubo Cardiomyopathy/diagnosis/drug therapy/*etiology ; Treatment Outcome

Medically refractory ventricular tachycardia (VT) storm can be controlled with radiofrequency catheter ablation (RFCA), however, it may be difficult to control in some patients with hemodynamic overload. We experienced a patient with intractable VT storm controlled by hemodynamic unloading. The patient had mid-septal hypertrophic cardiomyopathy with an implantable cardioverter defibrillator (ICD) back-up. Because of the severe mid-septal hypertrophy, his left ventricle (LV) had an hourglass-like morphology and showed apical ballooning; the focus of VT was at the border of apical ballooning. Although we performed VT ablation because of electrical storm with multiple ICD shocks, VT recurred 1 hour after procedure. As the post-RFCA monomorphic VT was refractory to anti-tachycardia pacing or ICD shock, we reduced the hemodynamic overload of LV with beta-blockade, hydration, and sedation. VT spontaneously stopped 1.5 hours later and the patient has remained free of VT for 24 months with beta-blockade alone. In patients with VT storm refractory to antiarrhythmic drugs or RFCA, the mechanism of mechano-electrical feedback should be considered and hemodynamic unloading may be an essential component of treatment.
Cardiomyopathy, Hypertrophic/complications/diagnosis/*physiopathology/therapy ; Catheter Ablation ; Electrocardiography ; Gated Blood-Pool Imaging ; Heart Catheterization ; Humans ; Male ; Middle Aged ; Tachycardia, Ventricular/diagnosis/etiology/*physiopathology/therapy ; Takotsubo Cardiomyopathy/complications/diagnosis/*physiopathology/therapy

Anticoagulants ; therapeutic use ; Cardiomyopathy, Hypertrophic ; complications ; diagnostic imaging ; therapy ; Coronary Angiography ; Death, Sudden, Cardiac ; prevention & control ; Defibrillators, Implantable ; Echocardiography ; Electric Countershock ; Electrocardiography ; Heart Aneurysm ; complications ; diagnostic imaging ; therapy ; Humans ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Tachycardia, Ventricular ; diagnosis ; etiology ; therapy