Dr. Jonathan Hestrin Lerner, MD

Just as with a standard pacemaker, a biventricular pacemaker consists of a small battery pack and electrical leads, or small wires that conduct electricity to the heart. CRT pacemakers have two or three leads, placed in the upper and lower chambers of the heart. The device measures the contractions of the heart, and if the heart begins to beat out of time it will send small, rhythmic pulses of electricity to resynchronize (hence the name 'cardiac resynchronization therapy) the contractions. This allows the heart to pump blood to the rest of the body more efficiently. Sometimes a CRT is combined with a different kind of device called an implantable cardioverter-defibrillator or ICD, which uses a higher burst of energy to restart the heart if it stops suddenly.

When a biventricular pacemaker is inserted, the wire leads are usually placed via a small incision near the shoulder, then threaded through a vein to the heart. The battery pack is placed under the skin of the chest near the collarbone. Once everything is in place, the leads are connected to the battery, and the CRT can begin helping the heart beat correctly.

It is normal to experience swelling and discomfort as the incisions from surgery heal. It takes time for the heart to adjust to the pacemaker, so vigorous activity should be kept to a minimum for the first few weeks. Strong magnetic fields may affect how the CRT functions, so patients may be advised to avoid them. As patients heart begins to pump blood more effectively, they should soon begin to feel stronger and less fatigued.

There are two main types of stroke: ischemic stroke and hemorrhagic stroke. Ischemic stroke occurs more commonly and is when a blood vessel in the brain becomes blocked. Blockages are caused by blood clots and built-up plaque (deposits of fat and cholesterol), which leads to atherosclerosis, a condition where the blood vessels narrow and harden. The resultant restricted blood flow may lead to an ischemic stroke by blocking essential oxygen to the brain, causing the heart to exert more effort to pump blood.

Hemorrhagic stroke occurs when a blood vessel in or around the brain ruptures. The burst vessel leaks blood into surrounding brain tissue, causing irreparable brain damage.

Hemorrhagic strokes are less common and may occur from head injuries, brain aneurysms, brain tumors, and bleeding disorders, amongst other conditions.

Both ischemic and hemorrhagic strokes require immediate medical treatment. Medical intervention can prevent severe and life-threatening brain damage. Signs of stroke include:

-Disorientation or confusion

-Difficulty speaking

-Difficulty walking

-Impaired vision

-Weakness in the face, legs, or arms

-Severe headaches

When someone suspected of having a stroke reaches the hospital, the patient will usually receive a CT or other scan that provides an image of the brain. The scan results can reveal clotted or leaking blood in the brain. Physical exams, neurological exams, and blood tests may also be used to check for blood clotting and sugar. Treatment begins generally immediately if a stroke is detected.

Medical treatment for ischemic strokes includes a thrombolytic medicine which breaks up and disperses blood clots. This medicine can greatly improve stroke recovery and long-term health. However, the thrombolytic medicine must be administered as soon as possible to achieve these results. Other treatments for ischemic strokes are blood thinners and thrombectomy, a surgical procedure to remove a blood clot in the brain. Thrombectomy is performed by inserting a catheter (thin needle) into the artery to reach the blood clot and mechanically remove it. With the clot removed, normal blood flow to the brain resumes. Thrombectomy is typically performed at most six hours after a patient shows signs of a stroke.

Hemorrhagic strokes are treated with blood-saving medication and surgery. For a hemorrhagic stroke caused by the rupture of an aneurysm (blood vessel bulges), surgery to stem the bleeding aneurysm and vessel may be used. One surgical technique is stent-assisted coiling, which adds a stent (small wire-meshed tube) into the blood vessel to block the leaking opening of the aneurysm. A non-surgical procedure is endovascular coiling, where a catheter (thin, hollow needle) places a platinum wire coil at the spot of the aneurysm. The coil blocks bleeding and prevents the aneurysm from continuing to leak blood. These procedures are usually combined with blood-thickening medications. Blood transfusions may be administered if substantial blood loss has occurred.

Since stroke patients may have lost some essential functions while the blood flow to their brains was obstructed, both ischemic stroke and hemorrhage stroke patients may receive post-stroke rehabilitation to rebuild their physical and mental abilities. Some restorative treatments include occupational, physical, and speech therapy. Patients may also receive care from neurologists, who can assist patients in recovering certain brain functions and cognitive abilities, and rehabilitation psychologists, who may help patients with their emotional, behavioral, and cognitive recovery. Some stroke patients require lengthy rehabilitation and may never fully regain function, while others may recover more quickly. While the fastest recovery improvements are usually seen in the first three or four months, stroke rehabilitation can last for years.

If someone begins to show signs of stroke, contact emergency services and call 9-1-1 immediately since blood flow must be restored as soon as possible to help avoid significant brain damage. If an ambulance takes the person to the hospital, paramedics can initiate stroke treatment as soon as the patient enters the ambulance, allowing for more prompt medical intervention and care.