Biventricular pacing, also known as Cardiac Resynchronization Therapy (CRT), is a medical treatment that uses a pacemaker to help the heart pump blood more effectively. This therapy aims to coordinate the contractions of the heart’s lower chambers, the ventricles, to improve overall heart function and pumping efficiency for individuals with certain heart conditions.
The Need for Biventricular Pacing
Biventricular pacing addresses an issue often seen in individuals with chronic heart failure, particularly those with reduced ejection fraction. In a healthy heart, the left and right ventricles contract in a synchronized manner, efficiently pushing blood out to the body and lungs. In heart failure, however, the electrical signals that coordinate these contractions can become delayed or disorganized, leading to ventricular dyssynchrony.
This dyssynchrony means the ventricles do not contract at the same time, reducing the heart’s ability to pump blood effectively. For example, one part of the ventricle might contract early while another is delayed, causing inefficient pumping and reduced blood flow. This uncoordinated movement places additional strain on the already weakened heart, worsening symptoms such as fatigue and shortness of breath.
How Biventricular Pacing Works
Biventricular pacing, or Cardiac Resynchronization Therapy (CRT), employs a specialized pacemaker device to restore coordinated ventricular contractions. This device consists of a pulse generator, which is a small, battery-powered unit, and typically three leads (thin, insulated wires). One lead is usually placed in the right atrium, another in the right ventricle, and a third in the left ventricle.
The lead for the left ventricle is often threaded through a vein called the coronary sinus, which allows access to the outer wall of the left ventricle. Once positioned, the pulse generator delivers precisely timed electrical impulses simultaneously to both the right and left ventricles. This synchronized electrical stimulation helps the ventricles contract in a more coordinated fashion, improving the heart’s pumping efficiency and increasing the amount of blood ejected with each beat.
The Implantation Process
The implantation of a biventricular pacemaker is a surgical procedure typically performed in a hospital setting. Before the procedure begins, the patient usually receives a local anesthetic to numb the area, along with a sedative to help them relax. A small incision, usually about 2 to 3 inches long, is made in the skin underneath the collarbone, often on the non-dominant side of the chest.
Through this incision, the doctor guides the pacemaker leads into a large vein and then carefully advances them into the appropriate heart chambers using X-ray guidance. Once the leads are securely in place, they are connected to the pulse generator. The pulse generator is then placed in a small pocket created under the skin in the upper chest. The entire procedure typically lasts between 1 and 3 hours, and patients often remain in the hospital overnight for observation and initial recovery.
Living with a Biventricular Pacemaker
After the biventricular pacemaker implantation, patients typically experience an initial recovery period, often involving avoiding strenuous activity and heavy lifting for about one to two weeks to allow the leads to settle. Regular follow-up appointments are necessary to ensure the device is functioning correctly and to check its battery life. These checks can often be done remotely, with in-person visits typically occurring every six months or as advised by the healthcare provider.
While living with a biventricular pacemaker, most normal daily activities can be resumed, but certain precautions are advised. Patients should avoid close or prolonged contact with devices that have strong magnetic fields, such as some cell phones, headphones, and certain medical equipment like MRI machines (unless the pacemaker is specifically designed to be MRI-safe). Carrying a pacemaker identification card is also recommended, especially when going through security checkpoints. Many patients experience significant improvements in their heart failure symptoms and overall quality of life, with the device potentially prolonging life by an average of 8.5 to 20 years, depending on individual health factors.