Shengmei Qin

Effect of Cardiac Resynchronization Therapy on Myocardial Fibrosis and Relevant Cytokines in a Canine Model with Experimental Heart Failure

Though cardiac resynchronization therapy (CRT) has now proved to be effective on cardiac reverse remodeling, data on the underlying molecular changes are limited. The present study aims to investigate the expression of cytokines concerning myocardial fibrosis in dyssynchronous heart failure (HF) and the potential benefits of CRT.

A new score system for predicting response to cardiac resynchronization therapy

BACKGROUND The aim of this study was to establish a score system derived from clinical, echocardiographic and electrocardiographic indexes and evaluate its clinical value for cardiac resynchronization therapy (CRT) patient selection. METHODS Ninety-three patients receiving CRT were enrolled. A patient selection score system was generated by the clinical, echocardiographic and electrocardiographic parameters achieving a significant level by univariate and multivariate Cox regression model. The positive response to CRT was a left ventricular end systolic volume decrease of ≥ 15% and not reaching primary clinical endpoint (death or re-hospitalization for heart failure) at the end of follow-up. RESULTS Thirty-nine patients were CRT non-responders (41.94%) and 54 were responders (58.06%). A 4-point score system was generated based on tricuspid annular plane systolic excursion (TAPSE), longitudinal strain (LS), and complete left bundle branch block (CLBBB) combined with a wide QRS duration (QRSd). The sensitivity and specificity for prediction of a positive response to CRT at a score > 2 were 0.823 and 0.850, respectively (AUC: 0.92295% CI 0.691-0.916, p< 0.001). CONCLUSIONS A patient selection score system based on the integration of TAPSE, LS and CLBBB combined with a wide QRSd can help to predict positive response to CRT effectively and reliably.

Electro-echocardiographic Indices to Predict Cardiac Resynchronization Therapy Non-response on Non-ischemic Cardiomyopathy

Cardiac resynchronization therapy (CRT) threw lights on heart failure treatment, however, parts of patients showed nonresponse to CRT. Unfortunately, it lacks effective parameters to predict CRT non-response. In present study, we try to seek effective electro-echocardiographic predictors on CRT non-response. This is a retrospective study to review a total of 227 patients of dyssynchronous heart failure underwent CRT implantation. Logistic analysis was performed between CRT responders and CRT non-responders. The primary outcome was the occurrence of improved left ventricular ejection fraction 1 year after CRT implantation. We concluded that LVEDV > 255 mL (OR = 2.236; 95% CI, 1.016–4.923) rather than LVESV > 160 mL (OR = 1.18; 95% CI, 0.544–2.56) and TpTe/QTc > 0.203 (OR = 5.206; 95% CI, 1.89–14.34) significantly predicted CRT non-response. Oppositely, S wave > 5.7 cm/s (OR = 0.242; 95% CI, 0.089–0.657), E/A > 1 (OR = 0.211; 95% CI, 0.079–0.566), E’/A’ > 1 (OR = 0.054; 95% CI, 0.017–0.172), CLBBB (OR = 0.141; 95% CI, 0.048–0.409), and QRS duration >160 ms (OR = 0.52; 95% CI, 0.305–0.922) surprisingly predicted low-probability of CRT non-response.

Impact of interlead distance on immediate and mid-term response to cardiac resynchronization therapy

Abstract Objectives. It is currently recommended that the left ventricular (LV) lead be placed at the posterolateral or lateral wall of heart during cardiac resynchronization therapy (CRT). The aim of our study is to evaluate the influence of interlead distance on immediate and mid-term response to CRT with altered right ventricular (RV) pacing site. Design. A total of 35 consecutive patients underwent CRT for standard indications. RV pacing site was altered from RV outflow tract (RVOT) to RV apex (RVA) in the course of implantation, permitting assessment of a “poorer response” and a “better response” site based on intraprocedural aortic velocity time integral (aVTI). LV–RV interlead distances were compared between these sites during operation. We also made a comparison of the interlead distances between responders and non-responders 6 months after CRT. Results. In the process of CRT implantation, the better response site showed significantly larger interlead distance (16.5 ± 4.4 cm vs.12.4 ± 5.6 cm, p = 0.001) as well as its vertical component (9.8 ± 4.8 cm vs. 4.3 ± 2.8 mm, p = 0.001) on lateral fluoroscopy view as compared with the poorer response site. Furthermore, RVA proved more likely to be the “better response” site than RVOT (91% vs. 9%, p = 0.001). At 6-month -up, responders demonstrated larger direct interlead distance (18.1 ± 4.5 cm vs. 14.8 ± 3.5 cm, p = 0.011) and horizontal interlead distance (14.1 ± 6.6 cm vs. 8.3 ± 6.1 cm, p = 0.004) on the lateral radiograph in comparison with non-responders with great significance. Conclusions. Larger interlead distance on lateral fluoroscopy view is associated with more favorable immediate and mid-term response to CRT. Use of these findings may help to maximize the benefit derived from CRT.

The Roles of the Q (q) Wave in Lead I and QRS Frontal Axis for Diagnosing Loss of Left Ventricular Capture During Cardiac Resynchronization Therapy

Loss of left ventricular (LV) capture may lead to deterioration of heart failure in patients with cardiac resynchronization therapy (CRT). Recognition of loss of LV capture in time is important in clinical practice.

Comparison of single-coil lead versus dual-coil lead of implantable cardioverter defibrillator on lead-related venous complications in a canine model

PurposeDual- coil lead (DCL) of implantable cardioverter defibrillator (ICD) is preferred clinically in patients. However, it is related to higher risk of venous stenosis and thrombosis. The present study was done to compare the fibrosis and extraction of the leads between the single-coil lead (SCL) and DCL in animal models.MethodsThis was a chronic animal study with a follow-up duration of 6 months. Twenty mongrel dogs were randomly divided into DCL group or SCL group. Venography was performed before the sacrifice to evaluate the venous stenosis in vivo. The maximum pulling-out tension of the ICD lead was measured by a tensometer. Hematoxylin-eosin stain and toluidine blue O stain were applied to show the pathological changes of the superior vena cava (SVC) to evaluate the fibrosis and the thickness of the SVC adjacent to the leads.ResultsThe DCL group showed higher incidence of venous stenosis (OR = 31.5; 95% CI, 2.35–422.3; p = 0.005). It revealed increased tension to extract the leads in the DCL group (5.96 ± 1.86 vs. 3.68 ± 1.46 N, p = 0.027). The difference of venous wall thickness of SVC was 4.3 ± 0.3 fold-changes between two groups (p = 0.007). Moreover, the degree of venous wall fibrosis in DCL group was more serious than that it in SCL group (3.61 ± 1.26 vs. 1.08 ± 1.35 mm2, p = 0.015).ConclusionThe DCL was proved to increase thrombosis, fibrosis, and stenosis in the SVC. Likewise, the DCL was mechanically harder to be extracted than the SCL. Our study showed that lead-related complications of the DCLs were higher than those of the SCLs regardless of the equal defibrillation thresholds between them. Results of the present study would help to choose the proper lead which could be removed.

Electrocardiographic parameters effectively predict ventricular tachycardia/fibrillation in acute phase and abnormal cardiac function in chronic phase of ST-segment elevation myocardial infarction

Abnormal cardiac repolarization is closely associated with ventricular tachycardia/ventricular fibrillation (VT/VF). Myocardial ischemia and infarction aggravate cardiac repolarization dispersion, and VT/VF could be lethal in the early stage of ST‐segment elevation myocardial infarction (STEMI). Unfortunately, VT/VF cannot be effectively predicted in current clinical practice. The present study aimed to assess electrocardiographic parameters of the sinus rhythmic complex in relation to cardiac repolarization, e.g., QT interval and T‐peak to T‐end interval (TpTe), to independently predict VT/VF in acute STEMI. Additionally, we hypothesized that QT and TpTe of PVC would be also valuable to predict VT/VF in STEMI.

Could persistency of current of injury forecast successful active-fixation pacing lead implantation?

BACKGROUND Presence of adequate current of injury (COI) was recognized as a sign of favorable pacemaker lead outcome. Little is known regarding the value of its dynamic behavior. We sought to test whether persistency of COI could predict active-fixation pacing lead performance. METHODS COI was monitored up to 10min after right ventricular (RV) pacing electrode fixation. COI persistency was defined as the percentage of COI magnitude relative to its initial measurement. An unacceptable pacing threshold (≥1.0V in acute evaluation or ≥2.0V over 2-year follow-up) with or without lead dislodgement was considered as lead failure. RESULTS Lead implantation was attempted for 217 times in 174 patients (age 66.3±7.8years, 78 female). Acute lead failures occurred 43 times. Independent predictors of acute lead failure were RV enlargement (odds ratio [OR] 1.23, 95% confidential interval [CI] 1.11-2.04, P=0.033), absence of COI (OR 3.13, 95%CI 2.08-9.09, P=0.027), and COI persistency at 5min (OR 0.32, 95%CI 0.20-0.69, P=0.001) and 10min (OR 0.41, 95%CI 0.13-0.77, P=0.001). The optimal cutoffs were COI5min persistency ≥50% (sensitivity 81.4%; specificity 81.9%) and COI10min persistency ≥20% (sensitivity 86%; specificity 88.6%). There were 12 lead failures during 24.0±6.4months of follow-up. Patients with COI5min persistency ≥50% had higher event-free survival compared to those with COI5min persistency <50% (hazard ratio 3.54, 95% CI 1.04-12.06, P=0.043). CONCLUSIONS COI persistency appears to be a valuable indicator for both acute and long-term outcome of active-fixation pacemaker leads. A precipitous decline in COI may require more attention to make sure of the lead performance.

Mitochondrial calcium uniporter inhibition provides cardioprotection in pressure overload-induced heart failure through autophagy enhancement

BACKGROUND HF incurs high disease burden, and the effectiveness of known HF treatments is unsatisfactory. Therefore, seeking novel therapeutic target of HF is important. The present study aimed to investigate the role of the mitochondrial calcium uniporter (MCU) and its relationship with autophagy in overload-induced heart failure (HF). METHODS AND RESULTS In both early-stage and end-stage of pressure overload-induced HF, MCU appeared up-regulated along with heart enlargement, increased microtubule-associated proteins 1A/1B light chain 3B (LC3B) II/I ratio and autophagosome content, damaged cardiac function, and ventricular asynchrony. However, sequestosome-1 (SQSTM1/p62) level decreased indicating blockaded autophagic flux. Seven-week administration of MCU inhibitor ruthenium red improved cardiac function and mitigated its pathological change. MCU inhibition maintained mitochondrial integrity, increased LC3B II/I ratio, up-regulated Parkin and Pink1, and down-regulated SQSTM1/p62. MCU inhibition also alleviated ventricular asynchrony of HF, and this might be related to connexin-43 up-regulation. In vitro study validated intervention on MCU leading to elevation of autophagy and mitophagy. MCU inhibition could partly prevent from excessive cellular enlargement induced by isoprenaline. CONCLUSIONS In summary, MCU inhibition played an important role in pressure overload-induced heart failure through autophagy and mitophagy enhancement, and intervention on MCU offered cardioprotective effects. To our knowledge, the role of MCU in HF and its relationship with autophagy and mitophagy are firstly disclosed. Moreover, our study suggests that MCU inhibition could be explored as a novel therapeutic concept in HF.

Can the Prognosis of Cardiac Resynchronization Therapy Be Predicted by Gated SPECT

Purpose The aim of this study was to evaluate the role of gated myocardial perfusion SPECT (GMPS) phase parameters (phase SD and histogram bandwidth) in predicting the short-term response to cardiac resynchronization therapy (CRT) as left ventricle (LV) remodeling and the long-term effect as all-cause mortality or cardiac transplantation and hospitalization for heart failure. Patients and Methods This prospective observational study included 63 consecutive patients undergoing CRT from May 2008 to April 2014. Before CRT, patients underwent evaluation of New York Heart Association functional class, standard 12-lead ECG, 99mTc-MIBI GMPS, and 2-dimensional echocardiography. The patients were grouped according to complete left bundle-branch block (CLBBB). Follow-up was done every 6 months after pacemaker implantation. The short-term end point was reverse LV remodeling in 6 to 12 months follow-up, and the long-term primary end point was all-cause mortality or cardiac transplantation. The secondary end point was hospitalization for heart failure. Results Reverse LV remodeling showed in 60.9% (39/63) patients (74.5% CLBBB [35/47] vs 25.0% non-CLBBB [4/16], P < 0.001). Phase SD less than 55 degrees, CLBBB, and left atrium diameter were independent predictive factors for reverse LV remodeling. At a median follow-up of 39.76 months, there were 17 deaths and 2 transplantations (17.0% CLBBB vs 68.8% non-CLBBB, P < 0.001). Seventeen patients required hospitalization more than once for heart failure, and 2 underwent heart transplantation (14.9% CLBBB vs 62.5% non-CLBBB, P < 0.001). Multivariate logistic regression showed that only CLBBB was an independent predictive factor for both end points. Conclusions The GMPS parameters were not independent predictive factors for all-cause mortality or cardiac transplantation and hospitalization for heart failure.