Fen Qin

Coupling interval variability: A new diagnostic method for distinguishing left from right ventricular outflow tract origin in idiopathic outflow tract premature ventricular contractions patients with precordial R/S transition at lead V3

BACKGROUNDnTo distinguish left ventricular outflow tract (LVOT) from right ventricular outflow tract (RVOT) origin in idiopathic outflow tract premature ventricular contractions (IOT-PVCs) patients with precordial R/S transition at lead V3 is still a challenge. We sought to develop a new electrocardiography (ECG) method for distinguishing LVOT from RVOT origin in IOT-PVCs patients with precordial R/S transition at lead V3.nnnMETHODSnWe analyzed the surface 12-lead ECG characteristics and the difference of coupling interval variability (CIV) of PVCs between distinct origin sites in a retrospective cohort of IOT-PVCs patients with precordial R/S transition at lead V3 who underwent successful radiofrequency catheter ablation (RFCA) to develop a new diagnostic method, then validated it in a prospective cohort.nnnRESULTSnA total of 196 consecutive patients (41u202f±u202f15u202fyears, 36.7% male) underwent RFCA of IOT-PVCs between January 2014 and August 2016. Among them, 68 patients (34.7%, 23 male) with precordial R/S transition at lead V3 constituted the retrospective cohort. Based on the areas under the receiver operating characteristic curves (AUCs), a CIVu202f>u202f100u202fms with the largest value of AUC was selected to develop a new diagnostic method with a specificity of 93.9% and an accuracy of 92.6%. It correctly identified the origin site of 38 from 41 patients in the prospective cohort, demonstrating a 96.8% specificity and 92.7% accuracy.nnnCONCLUSIONSnWe presented a new simple method, a CIVu202f>u202f100u202fms which could reliably distinguish LVOT from RVOT origin in IOT-PVCs patients with precordial R/S transition at lead V3.

Catheter ablation for treatment of patients with atrial fibrillation and heart failure: a meta-analysis of randomized controlled trials

BackgroundThere is a little evidence for the effects of catheter ablation (CA) on hard endpoints in patients with atrial fibrillation (AF) and heart failure (HF).MethodsPubMed, Embase and Cochrane Library were searched for randomized controlled trials (RCTs) enrolling patients with AF and HF who were assigned to CA, rate control or medical rhythm control groups. This meta-analysis was performed by using random-effect models.ResultsSeven RCTs enrolling 856 participants were included in this meta-analysis. CA reduced the risks of all-cause mortality (risk ratio [RR] 0.52, 95% CI 0.35 to 0.76), HF readmission (RR 0.58, 95% CI 0.46 to 0.66) and the composite of all-cause mortality and HF readmission (RR 0.55, 95% CI 0.47 to 0.66) when compared with control. But there was no significant difference in cerebrovascular accident (RR 0.56, 95% CI 0.23 to 1.36) between two groups. Compared with control, CA was associated with improvement in left ventricular ejection fraction (mean difference [MD] 7.57, 95% CI 3.72 to 11.41), left ventricular end systolic volume (MD -14.51, 95% CI -26.84 to −u20092.07), and left ventricular end diastolic volume (MD -3.78, 95% CI -18.51 to 10.96). Patients undergoing CA exhibited increased peak oxygen consumption (MD 3.16, 95% CI 1.09 to 5.23), longer 6-min walk test distance (MD 26.67, 95% CI 12.07 to 41.27), and reduced Minnesota Living with Heart Failure Questionnaire scores (MD -9.49, 95% CI -14.64 to −u20094.34) than those in control group. Compared with control, CA was associated with improved New York Heart Association class (MD -0.74, 95% CI -0.83 to −u20090.64) and lower B-type natriuretic peptide levels (MD -105.96, 95% CI -230.56 to 19.64).ConclusionsCA was associated with improved survival, morphologic changes, functional capacity and quality of life relative to control. CA should be considered in patients with AF and HF.

Is subcutaneous implantable cardioverter-defibrillator testing effective and safe for patients with hypertrophic cardiomyopathy?

We found the article “Effectiveness of subcutaneous implantable cardioverter-defibrillator testing in patients with hypertrophic cardiomyopathy” by Maurizi et al. [1] to be very interesting, which has great clinical significance for ICD implantation and defibrillation testing (DT) in young hypertrophic cardiomyopathy (HCM) patients. Subcutaneous implantable cardioverter-defibrillator (S-ICD) was adopted by ESC guideline [2] in 2015 as an alternative to transvenous defibrillators in patients with an ICD indication when pacing therapy for bradycardia, cardiac resynchronization or antitachycardia pacing is not needed. And it could help eliminate the morbidity related to transvenous lead malfunctions and endocarditis in HCM patients [3]. This study [1] showed the effectiveness of acuteDTof S-ICD in termination of VT/VF in HCM patients. However, we have some reservations about this paper. Firstly, the article did not describe the evaluation of the risk and possible complications of DT, such asmyocardial damage, transient left ventricular function decrease, thrombotic stroke in AF patients and even DT related death [4]. Secondly, there are differences in