Aged ; Cardiac Resynchronization Therapy ; methods ; Cardiac Resynchronization Therapy Devices ; China ; Female ; Humans ; Male

Cardiac resynchronization therapy (CRT) is a major breakthrough in therapy for patients with advanced congestive heart failure, however, a number of key clinical research questions remain, perhaps most importantly the issue of why apparently suitable patients do not respond to CRT. These issues are also relevant to patients who do respond to CRT as potentially their response might be further increased. Though patients do not respond to CRT because of many known postulated reasons, we review the importance of maintaining atrioventricular intrinsic conduction during CRT in this paper, which maybe is one of methods to reduce the rates of non-response to CRT.
Cardiac Resynchronization Therapy ; methods ; Heart Conduction System ; physiopathology ; Humans

PATIENTS with chronic heart failure (CHF) have a high incidence of atrial/ventricular arrhythmias which seriously affect life span and quality of life. Cardiac re-synchronization therapy (CRT) can improve cardiac function and reverse myocardial remodeling, therefore improving the quality of life and reducing mortality. CRT with Home-Monitoring (HM) can be used to monitor cardiac arrhythmias and other heart physiological indexes such as intrathoracic impedance and hemodynamics. Through wireless satellites, the data from the patients are sent to a monitor center for analysis. Doctors can identify emergent information and make a rapid diagnosis based on the information stored in the monitor center. CRT with HM has been verified as a valid method to optimize drug treatment according to individual parameters.
Cardiac Resynchronization Therapy ; methods ; Cardiac Resynchronization Therapy Devices ; Chronic Disease ; Heart Failure ; drug therapy ; Heart Function Tests ; Humans ; Remote Sensing Technology ; instrumentation ; methods ; Treatment Outcome

OBJECTIVETo review the updated research progress about the application of echocardiography in resynchronization treatment of chronic heart failure patients.

DATA SOURCESThe data used in this review were from PubMed, published in English and using the key terms "heart failure", "echocardiography" and "cardiac resynchronization therapy".

STUDY SELECTIONRelevant articles were reviewed and selected to address the stated purpose.

RESULTSIncreasing numbers of studies have suggested the importance of echocardiography in resynchronization treatment of chronic heart failure patients. Echocardiography can evaluate atrioventricular, inter- and intra-ventricular mechanical dyssynchrony before cardiac resynchronization therapy (CRT), as a guidance to assess the optimal left ventricular (LV) pacing location, optimize the atrioventricular and interventricular delays and predict response to CRT.

CONCLUSIONSEchocardiography is both non invasive and easily repeatable, and plays a crucial role in appraisal of heart synchronism, instruction of actuator placement, optimization of the device procedure, and prediction of the response to CRT.

Cardiac Resynchronization Therapy ; methods ; Echocardiography ; methods ; Heart Failure ; diagnostic imaging ; therapy ; Humans ; Radiography

Technologies associated with cardiac resynchronization therapy (CRT) devices and lead systems have progressed. However, dislocation after coronary sinus (CS) lead placement continues to be a problem. We reported on the patient treated with CRT, in whom dislocation of CS lead occurred. In the case, we tried to reposition the CS lead without the left heart delivery system only using pre-shaped stylet and guidewire, and the dislocated CS lead could be successfully repositioned by the method. The method of only using a pre-shaped stylet and guidewire is easier than the conventional way, and it can shorten procedure duration and fluoroscopy time, as well as reduce the cost of treatment, but it is not always feasible.
Cardiac Resynchronization Therapy ; methods ; Coronary Sinus ; Humans ; Male ; Middle Aged ; Pacemaker, Artificial

BACKGROUNDCardiac resynchronization therapy (CRT) is an effective electrical therapy for patients with moderate to severe heart failure and cardiac dyssynchrony. This study aimed to investigate the degree of acute left ventricular (LV) resynchronization with biventricular pacing (BVP) at different LV sites and to examine the feasibility of performing transthoracic echocardiography (TTE) to quantify acute LV resynchronization during CRT procedure.

METHODSFourteen patients with NYHA Class III-IV heart failure, LV ejection fraction < or = 35%, QRS duration > or = 120 ms and septal-lateral delay (SLD) > or = 60 ms on tissue Doppler imaging (TDI), underwent CRT implant. TDI was obtained from three apical views during BVP at each accessible LV site and SLD during BVP was derived. Synchronicity gain index (Sg) by SLD was defined as (1 + (SLD at baseline--SLD at BVP)/SLD at baseline).

RESULTSSeventy-two sites were studied. Positive resynchronization (R+, Sg > 1) was found in 42 (58%) sites. R+ was more likely in posterior or lateral than anterior LV sites (66% vs. 36%, P < 0.001). Concordance of empirical LV lead implantation sites and sites with R+ was 50% (7/14).

CONCLUSIONSThe degree of acute LV resynchronization by BVP depends on LV lead location and empirical implantation of LV lead results in only 50% concordance with R+. Performing TTE during CRT implantation is feasible to identify LV sites with positive resynchronization.

Aged ; Cardiac Resynchronization Therapy ; methods ; Echocardiography ; methods ; Female ; Heart Failure ; therapy ; Humans ; Male ; Middle Aged ; Ventricular Dysfunction, Left ; therapy

BACKGROUNDCardiac resynchronization therapy (CRT) with biventricular pacing has demonstrated cardiac function improvement for treating congestive heart failure (HF). It has been documented that the placement of the left ventricular lead at the longest contraction delay segment has the optimal CRT benefit. This study described follow-up to surgical techniques for CRT as a viable alternative for patients with heart failure.

METHODSBetween April 2007 and June 2012, a total of 14 consecutive heart failure patients with New York Heart Association (NYHA) Class III-IV underwent left ventricular epicardial lead placements via surgical approach. There were eight males and six females, aged 36 to 79 years ((59.6 ± 9.2) years). The mean left ventricular ejection fraction (LVEF) was (33.6 ± 7.4)%. All patients were treated with left ventricular systolic dyssynchrony and underwent left ventricular epicardial lead placements via a surgical approach. Tissue Doppler imaging (TDI) and intraoperative transesophageal echocardiography were used to assess changes in left heart function and dyssynchronic parameters. Also, echo was used to select the best site for left ventricular epicardial lead placement.

RESULTSLeft ventricular epicardial leads were successfully implanted in the posterior or lateral epicardial wall without serious complications in all patients. All patients had reduction in NYHA score from III-IV preoperatively to II-III postoperatively. The left ventricular end-diastolic diameter (LVEDD) decreased from (67.9 ± 12.7) mm to (61.2 ± 7.1) mm (P < 0.05), and LVEF increased from (33.6 ± 7.4)% to (42.2 ± 8.8)% (P < 0.05). Left ventricular intraventricular dyssynchrony index decreased from (148.4 ± 31.6) ms to (57.3 ± 23.8) ms (P < 0.05).

CONCLUSIONSMinimally invasive surgical placement of the left ventricular epicardial lead is feasible, safe, and efficient. TDI can guide the epicardial lead placement to the ideal target location.

Adult ; Aged ; Cardiac Resynchronization Therapy ; methods ; Echocardiography ; methods ; Female ; Heart Failure ; therapy ; Humans ; Male ; Middle Aged ; Treatment Outcome

We report the effects of biventricular pacing in a patient with hypertrophic obstructive cardiomyopathy (HOCM) refractory to medical therapy. A 58-year-old man with HOCM had suffered from dyspnea, chest pain and palpitation for 5 years. Cardiac catheterization showed a left ventricular outflow tract (LVOT) gradient of 80 mmHg. He refused septal myomectomy and the septal ablation was not available. Based on intraoperative pressure measurements, he was implanted with biventricular pacing and LVOT gradient decreased to 10 mmHg. During the follow-up period of 6 months, the patient's symptoms were markedly improved. Biventricular pacing may be an alternative therapy for patients with HOCM.
Cardiac Resynchronization Therapy ; methods ; Cardiomyopathy, Hypertrophic ; diagnostic imaging ; pathology ; therapy ; Coronary Angiography ; Electrocardiography ; Humans ; Male ; Middle Aged

Cardiac resynchronization therapy (CRT) has been shown to reduce the risk of death and hospitalization in patients with advanced heart failure with left ventricular dysfunction. However, controversy remains regarding who would most benefit from CRT. We performed a meta-analysis, and meta-regression in an attempt to identify factors that determine the outcome after CRT. A total of 23 trials comprising 10,103 patients were selected for this meta-analysis. Our analysis revealed that CRT significantly reduced the risk of all-cause mortality and hospitalization for heart failure compared to control treatment. The odds ratio (OR) of all-cause death had a linear relationship with mean QRS duration (P=0.009). The benefit in survival was confined to patients with a QRS duration > or =145 ms (OR, 0.86; 95% CI, 0.74-0.99), while no benefit was shown among patients with a QRS duration of 130 ms (OR, 1.00; 95% CI, 0.80-1.25) or less. Hospitalization for heart failure was shown to be significantly reduced in patients with a QRS duration > or =127 ms (OR, 0.77; 95% CI, 0.60-0.98). This meta-regression analysis implies that patients with a QRS duration > or =150 ms would most benefit from CRT, and in those with a QRS duration <130 ms CRT implantation may be potentially harmful.
Bundle-Branch Block/physiopathology ; Cardiac Resynchronization Therapy/*methods ; Cardiac Resynchronization Therapy Devices ; Defibrillators, Implantable ; Electrocardiography ; Heart Failure/mortality/physiopathology/*therapy ; Humans ; Myocardial Contraction/*physiology ; Treatment Outcome ; Ventricular Dysfunction, Left/mortality/physiopathology/*therapy

BACKGROUNDCardiac resynchronization therapy (CRT) with biventricular pacing improves cardiac function, functional capacity and quality of life in selected patients with heart failure. The current study aimed to evaluate the efficacy of the intracardiac electrogram (IEGM)-based optimization method, QuickOpt(TM), in Chinese patients treated with CRT.

METHODSAortic time velocity integrals (AVTI) achieved at the sensed atrioventricular (AV), paced AV and interventricular (VV) interval settings recommended by both QuickOpt(TM) and standard echocardiographic optimization were measured in 101 patients. Consistency and the strength of the relationship between the two timing cycle optimization methods were assessed by intra-class correlation coefficient (ICC).

RESULTSThe ICC showed good agreement and correlation with what the AVTI achieved at the optimal sensed AV (ICC = 0.9683 (0.9535 - 0.9785)), paced AV (ICC = 0.9642 (0.9475 - 0.9757)) and VV (ICC = 0.9730 (0.9602 - 0.9817)) interval settings determined by the two optimization methods. The average time required by echocardiographic optimization and by QuickOpt(TM) were (78.32 ± 32.40) minutes and (1.98 ± 1.64) minutes respectively (P < 0.0001).

CONCLUSIONThe QuickOpt(TM) algorithm provides a quicker, simpler and reliable alternative to the standard method for timing cycle optimization.

Adult ; Aged ; Aged, 80 and over ; Cardiac Resynchronization Therapy ; methods ; Electrophysiologic Techniques, Cardiac ; methods ; Female ; Heart Failure ; therapy ; Humans ; Male ; Middle Aged ; Prospective Studies