Pacing systems dual chamber

FIGURE 11.9 Illustration of a dual-chamber pacing system. 

Fig 7.1 Posteroanterior a) and laterolateral (b) chest radiograph of a man referred for lead-related endocarditis. The patient has a dual chamber pacing system in the right pectoral region and three additional abandoned leads, for a total of two atrial and three ventricular leads... 

Fig. 18.1 Posteroanterior (A) and lateral (B) chest radiographs of a dual-chamber pacing system. The pulse generator is located in a left prepectoral position. The position of both atrial and ventricular leads is acceptable. The J on the atrial lead is adeqnate. The ventricnlar lead is not positioned in a true apical position but is well seated with adequate slack.

Fig. 18.2 Posteroanterior (A) and lateral (B) chest radiographs of a dual-chamber pacing system with the pulse...

Levine PA, Electrocardiography of bipolar single and dual-chamber pacing systems, Herzschrittmacher 1988 8 86-90. 

Upgrading Techniques for Dual-Chambered Pacing and Defibrillator Systems... 

The location of the spikes helps to identify the type of pacemaker system in situ. A spike before a P wave denotes atrial pacing, whereas one before the QRS complex identifies ventricular pacing. Spikes before both P waves and QRS complexes can be either dual chamber (atria and ventricle) or Bi-v pacing. As both chambers are synchronized in the Bi-v system only one spike is usually visible. Figures 8.4 and 8.5 show single and dual chamber pacemaker systems. 

In many ICD systems, pacing and sensing are hmited to the right ventricle (single-chamber ICDs), and usually, only a single lead is required. More often, a pace-sense lead is also inserted via the same transvenous route and is fixed in the right atrium (dual-chamber ICD). The right atrial lead provides... 

Fig. 7.2 Serial anteroposterior fluoroscopic images taken during transvenous removal of a left-sided dual-chamber implantable cardioverter-defibrillator (ICD) system. After placement of a temporary right-ventricular (RV) pacing system

Implantation of transvenous ICD systems employs techniques similar to those used for permanent pacemaker implantations, and is discussed in detail in a separate chapter in this book. Connecting ICD leads to the device is slightly different than connecting pacemaker leads to pacemaker generators. All ICD pulse generators have at least three ports for single chamber devices (four ports for dual chamber devices, and five ports for CRT-D). One LV port is for the pace/sense IS-1 terminal pin, and two are for the defibrillation coil (usually DF+ and DF-). The second DF port may be capped if a single coil... 

Fig. 18.28 Posteroanterior chest radiograph (A) and close-up view (B) from a patient with congenital heart disease and an abandoned dual-chamber endocardial pacing system. Two ventricular epicardial leads are connected with a Y connector to a single chamber ventricular pacemaker. On the close-up view (B) the arrow notes a defect in the lead adaptor just as it exits the connector block.

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