Biventricular pacemaker

Oguz E, Dagdeviren B, Bilsel T, et al. Echocardio-graphic prediction of long-term response to biventricular pacemaker in severe heart failure. Eur. J. Heart Fail. 2002 4 83-90. 

A 64-year-old woman with systemic lupus erythematosus took chloroquine for 7 years (cumulative dose 1000 g). She developed sjmcope, and the electrocardiogram showed complete heart block a permanent pacemaker was inserted. The next year she presented with biventricular cardiac failure, skin hyperpigmentation, proximal muscle weakness, and chloroquine retinopathy. Coronary angiography was normal. An echocardiogram showed a restrictive cardiomyopathy. A skeletal muscle biopsy was characteristic of chloroquine myopathy. Chloroquine was withdrawn and she improved rapidly with diuretic therapy. 

Recent studies demonstrate that cardiac resynchronization therapy (CRT) offers a promising approach to selected patients with chronic heart failure. Delayed electrical activation of the left ventricle, characterized on the ECG by a QRS duration that exceeds 120 ms, occurs in approximately one-third of patients with moderate to severe systolic heart failure. Since the left and right ventricles normally activate simultaneously, this delay results in asynchronous contraction of the left and right ventricles, which contributes to the hemodynamic abnormalities of this disorder. Implantation of a speciahzed biventricular pacemaker to restore synchronous activation of the ventricles can improve ventricular contraction and hemodynamics. Recent trials show improvements in exercise capacity, NYHA classification, quality of life, hemodynamic function, and hospitalizations. A device that combined CRT with an implantable cardioverter-defibrillator (ICD) improved survival in addition to functional status. CRT is currently indicated only in NYHA class ni-IV patients receiving optimal medical therapy (ACE inhibitors, diuretics, -blockers, and digoxin) and... 

Makaryus AN, Boutis L, Goldner B, Park CH (2007) Coronary sinus angioplasty and stenting for biventricular pacemaker left ventricular lead implantation. J Invasive Cardiol 19(5) E128-E130... 

Some authors recommend contralateral reimplantation as early as 36 h after extraction in patients with local symptoms only of device-related infection [10]. In some instances, it is considered safe to perform a contralateral same-day reimplantation [11]. The reasons for a same-day reimplantation are usually pacemaker (PM) dependency or hemodynamic need for CRT in case of biventricular pacing. In fact, the risk of subsequent CIED infections and venous thrombosis increases while maintaining a transvenous temporary device, and for this reason, it cannot be used indefinitely [12]. Same-day reimplantation is considered safe if the patient is clinically proven not to have active systemic bacteremia or infection by blood culture at the time of extraction and there is a lack of transesophageal echocardiographic evidence for endocarditis and the presence of a normal white blood cell count. 

Chugh A, Scharf C, Hall B, Cheung P, Good E, Horwood L, Oral H, Pelosi F, Jr., Morady F. Prevalence and management of inappropriate detection and therapies in patients with first-generation biventricular pacemaker-defibrillators. Pacing Clin Electrophysiol 2005 28 44-50. 

Management of a Biventricular Device. It has been estimated that up to 38% of patients with moderate to severe congestive heart failure due to left ventricular systolic dysfunction have intraventricular conduction delays with wide QRS complexes and ventricular dyssynchrony (79). Cardiac resynchronization therapy using a biventricular pacemaker is now a Class I indication therapy for systolic heart failure in patients with a QRS complex > 120 ms and left ventricular ejection fraction < 35% (80). Although cardiac resynchronization therapy decreases heart failure hospitalizations (81,82), as the overall number of patients with biventricular pacemakers and ICDs increase, more critical care patients will present with implanted biventricular devices, and familiarity with the management of these devices will become increasingly important. 

The book is divided into four sections. The first section describes pacing leads and pacemaker function. The second section focuses on device implantation. New to this edition is a chapter on implantation of left ventricular leads, used in the biventricular pacing systems intended to treat patients with heart failure. Purposely we have asked two experienced implanters to discuss then-personal methods for placing leads in the cardiac venous systems to illustrate the diversity of techniques and tricks of the trade. The third section reviews the use of implantable cardiac devices in particular clinical situations. All of the chapters from the first edition have been extensively revised new to this edition are chapters on device use for patients with atrial fibrillation, heart failure, and syncope, providing further evidence for the expanding indications... 

While upgrading a patient with CHF and a single chamber pacemaker to a biventricular ICD the following image is obtained. 

An 80-year-old male with chronic AF and a right pectoral dual chamber permanent pacemaker has just had a biventricular ICD (atrial port plugged) implanted at the left pectoral region. Prior to its removal the pacemaker is reprogrammed to a DDI mode after therapies in the ICD are disabled. The ICD pacing mode is VVI at 40 b.p.m. 

A biventricular pacemaker uses three leads one to pace the right atrium, one to pace the right ventricle, and one to pace the left ventricle. The left ventricular lead is placed in the coronary sinus. Both ventricles are paced at the same time, causing them to contract simultaneously, which improves CO. 

Pacemakers and implantable cardioverter-defibrillators BIVENTRICULAR PACEMAKER... 

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