Case Report: Left bundle branch pacing in an amyloid light-chain cardiac amyloidosis patient with atrioventricular block.

Introduction: Amyloid light-chain cardiac amyloidosis is a progressive infiltrative disease characterized by the deposition of amyloid fibrils in the cardiac tissue, which can cause serious atrioventricular block requiring pacemaker implantation. Left bundle branch pacing has emerged as an alternative method for delivering physiological pacing to achieve electrical synchrony of the left ventricle. However, left bundle branch pacing in patients with amyloid light-chain cardiac amyloidosis has not been studied in detail.

Noninvasive electrocardiography monitoring for very early recurrence predicts long-term outcome in patients after atrial fibrillation ablation.

Background: Atrial fibrillation (AF) is the most common sustained arrhythmia, and catheter ablation has been shown to be a highly effective treatment for patients with symptomatic AF. Very early recurrence (VER) of AF within 7 days after catheter ablation is common, but the clinical significance of VER remains unclear. We have examined the usefulness of the noninvasive electrocardiography monitor for the detection of VER and the relationship between VER and late recurrence (LR).

Effects of the short-term exposure to ambient air pollution on atrial fibrillation.

Background: Atrial fibrillation (AF) is an important arrhythmia associated with cardiovascular morbidity and mortality. This study is focused on exploring the potential relationship between short-term air pollution exposure and occurrence of AF.

Methods: A case-crossover design was used to investigate the effect of pollutants on AF occurrence among 100 patients from 2013 to 2014.

Distribution and predictors of hospital charges for haemorrhagic stroke patients in Beijing, China, March 2012 to February 2015: a retrospective study.

Objectives: The purpose of this study is to analyse hospital charges for patients with haemorrhagic stroke in China and investigate potential factors associated with inpatient charges.

Methods: The study participants were in-hospital patients with a primary diagnosis of haemorrhagic stroke from all the secondary and tertiary hospitals in Beijing during the period from 1 March 2012 to 28 February 2015. Distribution characteristics of detailed hospital charges were analysed.

The importance of Purkinje activation in long duration ventricular fibrillation.

Background: The mechanisms that maintain long duration ventricular fibrillation (LDVF) are unclear. The difference in distribution of the Purkinje system in dogs and pigs was explored to determine if Purkinje activation propagates to stimulate working myocardium (WM) during LDVF and WM pacing.

Methods And Results: In-vivo extracellular recordings were made from 1044 intramural plunge and epicardial plaque electrodes in 6 pig and 6 dog hearts.

[Causes of insufficient anticoagulation in Chinese patients with non-valvlar atrial fibrillation].

Objective: To evaluate the factors responsible for the insufficient application of oral anticoagulation (OAC) in Chinese patients with non-valvular atrial fibrillation.

Methods: The research is a single center registration study in a tertiary referral hospital in Beijing. The general characteristics, history of atrial fibrillation, comorbidities and anticoagulation treatment were obtained from all patients.

The amplitude of fibrillatory waves on leads aVF and V1 predicting the recurrence of persistent atrial fibrillation patients who underwent catheter ablation.

Objective: To evaluate whether the amplitude of fibrillatory wave (F wave) on electrocardiography could predict the recurrence in persistent atrial fibrillation (AF) patients who underwent catheter ablation.

Methods: All consecutive persistent AF patients who underwent catheter ablation at Peking Union Medical College Hospital between November 2006 and February 2012, were enrolled. The amplitude of F wave was measured on three orthogonal leads (leads I, V1 and aVF) on the Prucka CardioLab recording system.

The R-wave deflection interval in lead V3 combining with R-wave amplitude index in lead V1: a new surface ECG algorithm for distinguishing left from right ventricular outflow tract tachycardia origin in patients with transitional lead at V3.

Background: To distinguish left ventricular outflow tract (LVOT) from right ventricular outflow tract (RVOT) origin in idiopathic premature ventricular contractions or ventricular tachycardia (PVCs/VT) patients with transitional lead at V3 is still a challenge. We sought to develop a new electrocardiography (ECG) algorithm for distinguishing LVOT from RVOT origin in patients with idiopathic outflow tract PVCs/VT with precordial transitional lead at V3.

Methods: We analyzed the surface ECG characteristics in a retrospective cohort of idiopathic PVCs/VT patients with transitional lead at V3 who underwent successful radiofrequency catheter ablation and developed a new surface ECG algorithm, then validated it in a prospective cohort.

Elimination of fatal arrhythmias through ablation of triggering premature ventricular contraction in type 3 long QT syndrome.

Congenital long QT syndrome (LQTS) is the most common inherited arrhythmia, fatal arrhythmias are the main causes of sudden death, and often induced by the premature ventricular contractions (PVCs). Ablation of the triggering PVCs may eliminate the fatal arrhythmias and prevent the sudden death in patients with LQTS. We report a 19-year-old boy diagnosed with type 3 LQTS, frequent fatal arrhythmias induced by PVCs with the identical QRS morphology.

Poor prognosis in chronic heart failure patients with reduced ejection fraction in China.

Most Chinese cardiologists are challenged by the high mortality rate of heart failure (HF) in patients with reduced ejection fraction in China. This study was designed as a single-center, retrospective study. All consecutive HF patients with left ventricular ejection fraction (LVEF) ≤ 45% from January 1, 2007, to December 31, 2009, were enrolled.

Evolution of activation patterns during long-duration ventricular fibrillation in pigs.

Quantitative analysis has demonstrated five temporal stages of activation during the first 10 min of ventricular fibrillation (VF) in dogs. To determine whether these stages exist in another species, we applied the same analysis to the first 10 min of VF recorded in vivo from two 504-electrode arrays, one each on left anterior and posterior ventricular epicardium in six anesthetized pigs. The following descriptors were continuously quantified: 1) number of wavefronts, 2) wavefront fractionations, 3) wavefront collisions, 4) repeatability, 5) multiplicity index, 6) wavefront conduction velocity, 7) activation rate, 8) mean area activated by the wavefronts, 9) negative peak rate of voltage change, 10) incidence of breakthrough/foci, 11) incidence of block, and 12) incidence of reentry.

[Deviation of ST-segment and detection of infarction related artery in patients with acute inferior wall infarction].

Objective: To explore the characteristics of ST-segment deviation in patients with acute ST elevation myocardial infarction(STEMI)having only one vessel lesion in either left circumflex artery (LCX) or right coronary artery (RCA).

Methods: All AMI (acute myocardial infarction) patients were admitted into Peking Union Medical College Hospital from January 1996 to March 2009. They underwent coronary angiography (CAG).

[ST segment deviation in acute myocardial infarction with isolated disease of left anterior descending artery].

Objective: To analyze the characteristics of the electrocardiogram (ECG) of left anterior descending coronary artery (LAD) occlusion in patients with acute ST elevation myocardial infarction (STEMI).

Methods: Patients included were those diagnosed with STEMI in Peking Union Medical College Hospital from January 1996 to March 2009, and underwent coronary angiography (CAG). The infarction related artery (IRA) was LAD, and there were no significant stenosis in left circumflex artery and right coronary artery.

Utility of combined indexes of electrocardiography and echocardiography in the diagnosis of biopsy proven primary cardiac amyloidosis.

Objective: Primary cardiac amyloidosis (CA) is associated with poor prognosis. However, the noninvasive diagnostic tools are limited. The aim of the study is to assess the utility of combined indexes of electrocardiography (ECG) and echocardiography (ECHO) in the diagnosis of primary CA.

[Clinico-pathological evaluation of restrictive cardiomyopathy].

Objective: restrictive cardiomyopathy (RCM) is characterized by impairment of ventricular filling during diastole with preserved systolic function. The clinical and histopathological profile on endomyocardial biopsy of 25 consecutive patients with RCM was analyzed in this study.

Methods: twenty-five patients with diagnosis of RCM and underwent endomyocardial biopsy (EMB) were enrolled in the study.

[Electrocardiographic and echocardiographic features of patients with primary cardiac amyloidosis].

Objective: To summarize the electrocardiography and echocardiography features of patients with cardiac amyloidosis (CA) diagnosed by endo-myocardial biopsy (EMB).

Methods: A total of 20 consecutive patients [7 men, mean age (50 ± 12) years] referred for EMB because of clinical suspicion of CA from September 2006 to October 2009 were included in the study. Primary CA was diagnosed in 11 out of 20 patients (55%) by EMB and biomarkers examination.

Importance of endomyocardial biopsy in unexplained cardiomyopathy in China: a report of 53 consecutive patients.

Background: Although endomyocardial biopsy (EMB) plays a crucial role in the final diagnosis in patients with heart failure of unknown etiology, the invasive nature of this technique limits its clinical application in China. The purpose of this study was to evaluate the clinical application of EMB in diagnosing cardiomyopathy with unexplained etiologies in China.

Methods: Fifty-three consecutive patients (38 males, age 14 - 67 years, median 43 years) were included in the study who were initially diagnosed as unexplained cardiomyopathy and under EMB biopsy in Peking Union Medical College Hospital from 2006 to 2009.

Primary prevention of sudden cardiac death by implantable cardioverter-defibrillator therapy in Chinese patients with heart failure: a single-center experience.

Background: An implantable cardioverter-defibrillator (ICD) has been suggested for heart failure patients for primary prevention of sudden cardiac death. However, few data have been reported on the application of ICD as primary prevention of sudden cardiac death in China. We evaluated the value of primary prevention ICD therapy in Chinese patients with heart failure.

[Comparison of adenosine versus iloprost by acute vasodilator test in patients of pulmonary arterial hypertension complicated with connective tissue diseases].

Objective: To compare the acute hemodynamic effects of adenosine versus iloprost in patients of pulmonary arterial hypertension (PAH) complicated with connective tissue diseases.

Methods: During right heart catheterization, 18 patients of PAH complicated with connective tissue diseases sequentially received intravenous infusion of adenosine and inhaled iloprost. After the baseline hemodynamic data were obtained, an adenosine infusion was started and titrated to the maximal tolerated dose.

Intramural foci during long duration fibrillation in the pig ventricle.

For more than 50 years, it has been assumed that ventricular fibrillation (VF) is maintained solely by reentry in the working myocardium. This hypothesis has never been tested by recording VF with electrodes spaced sufficiently close to map activation sequences in 3D. We recorded the first 10 minutes of electrically induced VF from the anterior left ventricular (LV) free wall near the insertion of the anterior papillary muscle in 6 pigs.

Role of maximum rate of depolarization in predicting action potential duration during ventricular fibrillation.

During ventricular fibrillation (VF) only 39% of the variation in action potential duration (APD) is accounted for by the previous diastolic interval [DI((n-1))], i.e., restitution, and the previous APD [APD((n-1))], i.

Transmural and endocardial Purkinje activation in pigs before local myocardial activation after defibrillation shocks.

Background: Earliest recorded postshock myocardial activations in pigs originate in the subepicardium of the apex and lateral free wall of the left ventricle (LV) 30-90 ms after the shock.

Objective: The purpose of this study was to determine whether the Purkinje system is a candidate for the source of postshock activations by performing endocardial and transmural postshock activation mapping.

Methods: In five pigs, 32 plunge needles with 12 electrodes (1-mm spacing) were inserted into the LV apex and lateral free wall.