Computational Simulation of Biventricular Pacing in an Asymptomatic Human Heart

2011 ◽  
Author(s):  
Corey L. Murphey ◽  
Jonathan Wong ◽  
Ellen Kuhl
Keyword(s):  
Biventricular Pacing ◽  
Computational Simulation ◽  
Systolic Heart Failure ◽  
Cardiac Resynchronization ◽  
Conduction Delay ◽  
Intraventricular Conduction ◽  
Lead Placement ◽  
Pacemaker Leads ◽  
Pacing Lead ◽  
The Right

Cardiac resynchronization therapy (CRT) through biventricular stimulation was first used in the early 1990s as a treatment option for patients with systolic heart failure, intraventricular conduction delay, and other cardiac arrhythmias [1]. CRT, also known as biventricular pacing (BiVP), is an alternative to right ventricular stimulation, which induces dyssynchronous ventricular contraction. In BiVP, three pacing leads are usually placed on the myocardium of the right atrium, the right ventricle, and the left ventricle in the distal cardiac vein. Because there are no standardized loci for lead placement in BiVP, physicians rely on trial and error when inserting pacemaker leads and use electrocardiograms (ECG) to determine the effectiveness of the BiVP lead placement. The ECG measures the electrical conduction, contraction pacing, and projections of the anatomy of the myocardium. Abnormalities in the sinusoidal waves of the ECG reveal problems. Therefore, the ECG can depict a quantitative representation of the effectiveness of biventricular pacing lead placement.

scholarly journals Improvement in pump function with endocardial biventricular pacing increases with activation time at the left ventricular pacing site in failing canine hearts

2011 ◽  
Vol 301 (4) ◽  
pp. H1447-H1455 ◽  
Author(s):  
Elliot J. Howard ◽  
James W. Covell ◽  
Lawrence J. Mulligan ◽  
Andrew D. McCulloch ◽  
Jeffrey H. Omens ◽  
...  
Keyword(s):  
Heart Failure ◽  
Biventricular Pacing ◽  
Pressure Change ◽  
Left Ventricular ◽  
Cardiac Resynchronization ◽  
Activation Time ◽  
Lead Placement ◽  
Anterolateral Wall ◽  
The Right ◽  
Transmural Function

Recently, attention has been focused on comparing left ventricular (LV) endocardial (ENDO) with epicardial (EPI) pacing for cardiac resynchronization therapy. However, the effects of ENDO and EPI lead placement at multiple sites have not been studied in failing hearts. We hypothesized that differences in the improvement of ventricular function due to ENDO vs. EPI pacing in dyssynchronous (DYSS) heart failure may depend on the position of the LV lead in relation to the original activation pattern. In six nonfailing and six failing dogs, electrical DYSS was created by atrioventricular sequential pacing of the right ventricular apex. ENDO was compared with EPI biventricular pacing at five LV sites. In failing hearts, increases in the maximum rate of LV pressure change (dP/d t; r = 0.64), ejection fraction ( r = 0.49), and minimum dP/d t ( r = 0.51), relative to DYSS, were positively correlated ( P < 0.01) with activation time at the LV pacing site during ENDO but not EPI pacing. ENDO pacing at sites with longer activation delays led to greater improvements in hemodynamic parameters and was associated with an overall reduction in electrical DYSS compared with EPI pacing ( P < 0.05). These findings were qualitatively similar for nonfailing hearts. Improvement in hemodynamic function increased with activation time at the LV pacing site during ENDO but not EPI pacing. At the anterolateral wall, end-systolic transmural function was greater with local ENDO compared with EPI pacing. ENDO pacing and intrinsic activation delay may have important implications for management of DYSS heart failure.

scholarly journals Cardiac Resynchronization Therapy: Who is and who is not a Candidate? Who Decides?

1970 ◽  
Vol 11 (1) ◽  
Author(s):  
William F. McIntyre MD, FRCPC ◽  
Colette M. Seifer MB (Hons), FRCP(UK)
Keyword(s):  
Heart Failure ◽  
Health Care Providers ◽  
Systolic Heart Failure ◽  
Disease Process ◽  
Cardiac Resynchronization ◽  
Functional Mitral Regurgitation ◽  
Conduction Delay ◽  
Care Providers ◽  
Resynchronization Therapy ◽  
Intraventricular Conduction

It is estimated that nearly 500,000 Canadians are currently living with heart failure, a disease process associated with considerable morbidity and mortality. Despite significant evidence for effective medical therapies, heart failure remains one of the leading causes of hospitalization in Canada and patients with the disease experience an annual mortality of up to 10%.Approximately one in three patients with systolic heart failure have some degree of intraventricular conduction delay, manifest as increased QRS duration on electrocardiogram (ECG), the most common of which is left bundle branch block (LBBB). This conduction delay, or electrical dyssynchrony, can lead to mechanical uncoupling and inefficiency, which, in turn, can lead to exacerbation of systolic dysfunction, altered myocardial metabolism, functional mitral regurgitation, negative remodeling and worsening clinical outcomes.Cardiac resynchronization therapy (CRT), also known as biventricular pacing, involves coordinating contraction between the left (LV) and right ventricles (RV) through programmed pacing of both ventricles. CRT is an established non-pharmacological therapy for patients with systolic heart failure due to a low ejection fraction, who have a QRS >130 ms and who are symptomatic despite optimal medical therapy. In carefully selected patients, CRT has been shown to promote positive LV remodeling, increase functional capacity, improve quality of life, reduce heart failure hospitalizations and reduce mortality.2 CRT systems can include defibrillator capabilities (CRT-D) or act as a stand-alone pacemaker (CRT-P).The insertion of a CRT system consumes significant resource (costs), requires a commitment to regular clinical follow-up, and the acceptance of permanent implantation of a large medical device. Clinicians are tasked with identifying patients who would be expected to benefit from CRT and making the decision whether to proceed with CRT implantation. Therefore a careful consideration of the risks and benefits of this technology is required by both the healthcare providers and the patient.Herein we hope to offer guidance on identifying ideal candidates for CRT and to remind health care providers that the patients’ goals must be taken into consideration when counseling a patient for treatment with CRT.

scholarly journals Physiological pacing to improve cardiac resynchronization therapy non-responder and a tryst with calcified septum—a case report

2021 ◽  
Vol 73 (1) ◽  
Author(s):  
Vanita Arora ◽  
Francesco Zanon ◽  
Viveka Kumar ◽  
Vivek Kumar ◽  
Pawan Suri
Keyword(s):  
Case Report ◽  
Cardiac Resynchronization Therapy ◽  
Ischemic Cardiomyopathy ◽  
Cardiac Resynchronization ◽  
Conduction Delay ◽  
Resynchronization Therapy ◽  
Intraventricular Conduction ◽  
Technological Approach ◽  
Intraventricular Septum ◽  
Intraventricular Conduction Delay

Abstract Background As per the literature, patients with intraventricular conduction delay (IVCD) do not respond well to cardiac resynchronization therapy (CRT) alone. They need advanced technological approach and out of the box thinking for a good response. Case Ours is a case of ischemic cardiomyopathy with wide QRS-IVCD, a non-responder to CRT. While planning for replacement of the device for early replacement indicator (ERI), we decided to do His-optimized CRT/left bundle optimized CRT (HOT-CRT/LOT-CRT) for the patient. Conclusion The challenges we faced with the present available hardware paved a way for insisting on the limitation of the available lumenless lead to penetrate calcified the septum and importance of the pre-procedure evaluation of intraventricular septum (IVS) for calcification by more than just echocardiography.

Video-Assisted Implantation of a Left Ventricular Lead and Intrathoracic Tunneling to a Right-Sided CRT-D Device

2011 ◽  
Vol 6 (5) ◽  
pp. 341-343
Author(s):  
Thijs Stoker ◽  
Theo J. Klinkenberg ◽  
Alexander H. Maass ◽  
Massimo A. Mariani
Keyword(s):  
Left Ventricular ◽  
Pleural Space ◽  
Left Ventricular Lead ◽  
Cardiac Resynchronization ◽  
Ventricular Pacing ◽  
Video Assisted ◽  
Ventricular Lead ◽  
Pacing Lead ◽  
Left Ventricular Pacing ◽  
The Right

We describe two cases in which a biventricular implantable cardioverter defibrillator for cardiac resynchronization therapy had to be placed on the right side due to unsuitability of the left subclavian vein. Endocardial implantation of a left ventricular lead through the coronary sinus was previously attempted but was unsuccessful. Implantation of the epicardial left ventricular pacing lead was performed through video-assisted thoracic surgery on the left side. The connector end of the left ventricular pacing lead was tunnelized through the anterior mediastinum into the right pleural space. The right-sided pocket was then opened. A tunnel was created from the pocket to the thoracic wall, and the pleural space was entered over the second rib. The lead was retrieved from the right pleural space and connected with the Cardiac resynchronization therapy-device (CRT-D). Both procedures and postoperative periods were uneventful. Intrathoracic left-to-right tunneling of an epicardial left ventricular lead by video-assisted thoracic surgery is feasible and safe. It provides an alternative to subcutaneous tunneling.

scholarly journals Imaging predictive factors and exercise training in CRT patients

2016 ◽  
Vol 86 (1-2) ◽  
Author(s):  
Ana Abreu ◽  
Helena Santa Clara
Keyword(s):  
Single Photon ◽  
Imaging Techniques ◽  
Photon Emission ◽  
Mechanical Dyssynchrony ◽  
Left Ventricular ◽  
Cardiac Resynchronization ◽  
Conduction Delay ◽  
Lv Function ◽  
Scar Burden ◽  
Intraventricular Conduction

<p>Cardiac resynchronization therapy (CRT) is an established treatment for patients with moderate-to-severe chronic heart failure (CHF) and intraventricular conduction delay, which is identified by a QRS interval of 120msec or more on a 12-lead electrocardiogram (ECG). CRT improved functional capacity, reduced hospitalizations for worsening CHF and increased survival. However, about 30-40% of patients who underwent CRT were non-responders with no clinical or echocardiographic improvement. Imaging parameters for prediction of CRT response have been reviewed. Cardiac magnetic resonance (CMR), recognized as the gold standard to assess viability, has shown to obtain good results regarding quantification of scar burden. CMR-derived measures of mechanical dyssynchrony appear to predict the outcome of CRT, however they have not been externally validated. Nuclear imaging techniques, namely single-photon emission cardiac tomography (SPECT) provide data on scar burden and location, left ventricular (LV) function, LV contraction and mechanical dyssynchrony from a single scan. The presence, location and burden of myocardial scar have been shown to affect response to CRT. However, compared to CMR, the low spatial resolution of scintigraphy might overestimate the scar extent. This problem can be overcome by positron emission tomography (PET). SPECT has also been used to quantify dyssynchrony, using phase analysis. Imaging investigation is ongoing, trying to better identifying CRT non-responders. The combination of ExT in CRT has not been well investigated; however some data show different aerobic exercise modes and intensities can further improve CRT benefits. Data available on the effects of ExT in patients with CRT have been reviewed.</p>

scholarly journals Successful implantation of a biventricular pacing and defibrillator device via a persistent left superior vena cava

2013 ◽  
Vol 70 (12) ◽  
pp. 1162-1164
Author(s):  
Mihailo Vukmirovic ◽  
Lazar Angelkov ◽  
Filip Vukmirovic ◽  
Irena Tomasevic-Vukmirovic
Keyword(s):  
Heart Failure ◽  
Superior Vena Cava ◽  
Superior Vena ◽  
Biventricular Pacing ◽  
Severe Heart Failure ◽  
Vena Cava ◽  
Left Superior Vena Cava ◽  
Persistent Left Superior Vena ◽  
Lead Placement ◽  
The Right

Introduction. Persistent left superior vena cava is the most common thoracic venous abnormality which is usually asymptomatic, found incidentally during pacemaker implantation. The main problem is related to reaching the appropriate pacing site and ensuring stable lead placement. Case report. We reported a successful implantation of a biventricular pacing and defibrillator device (CRT-D) via a persistent left superior vena cava in a 55-year-old man with dilated cardiomyopathy and severe heart failure. A persistent left superior vena cava was detected during CRT-D implantation. We managed to position electrodes in the right ventricular outflow tract, a posterior branch of the coronary sinus and in the right atrium. Conclusion. Congenital anomalies of thoracic veins may complicate lead placement on the appropriate and stable position. The presented case demonstrates a successful biventricular pacing and defibrillator therapy device implantation in a patient with dilated cardiomyopathy and severe heart failure.

scholarly journals Alternative sites of ventricular pacing: His bundle pacing

2020 ◽  
Vol 90 (2) ◽  
Author(s):  
Francesco Vetta ◽  
Leonardo Marinaccio ◽  
Giampaolo Vetta
Keyword(s):  
Heart Failure ◽  
Biventricular Pacing ◽  
Scientific Evidence ◽  
Cardiac Pacing ◽  
Cardiac Conduction ◽  
Cardiac Resynchronization ◽  
Conduction Delay ◽  
Ventricular Pacing ◽  
His Bundle ◽  
His Bundle Pacing

Since its introduction right ventricular apical (RVA) pacing has been the mainstay in cardiac pacing. However, in recent years there has been an upsurge of interest in permanent His bundle pacing (HBP), given the scientific evidence of the harmful role of dyssynchronous ventricular activation, induced by RVA pacing, in promoting the onset of heart failure and atrial fibrillation. After an intermediate period in which attention was focused on algorithms aimed at minimizing ventricular pacing, with partially inadequate and harmful results, scientific attention shifted to HBP, which proved to ensure a physiological electro-mechanical activation of the ventricles. The encouraging results obtained have allowed the introduction of HBP in recent guidelines for cardiac pacing in patients with bradicardia and cardiac conduction delay. Recent studies have also demonstrated the potential of HBP in patients with left bundle branch block and heart failure. HBP is promising as an attractive way to achieve physiological stimulation in patients with an indication for cardiac resynchronization therapy (CRT). Comparative studies of HB-CRT and biventricular pacing have shown similar results in numerically modest cohorts, although HB-CRT has been shown to promote better ventricular electrical resynchronization as demonstrated by a greater QRS narrowing. A widespread use of this pacing tecnique also depends on improvements in technology, as well as further validation of effectiveness in large randomised clinical trials

Sign in / Sign up

Export Citation Format

Share Document