Better Health talks to US-board certified cardiologist and electrophysiologist Dr. Chotikorn Khunnawat about new and exciting innovative treatments for serious forms of cardiac arrhythmia – atrial fibrillation and bradycardia which also have been successful in the intervention of stroke and cardiac arrest.
Atrial fibrillation and stroke
Two recent cardiac technologies help patients live a better life: Left Atrial Appendage Occlusion for potential interventions of stroke in patients with atrial fibrillation and Leadless Pacemaker Implantation for patients with bradycardia (abnormally slow heartbeat) to prevent syncope and cardiac arrest.
Cardiac arrhythmia is a defect in the electrical system of the heart, which controls the heartbeat. Normal heart rates range from 60 to 100 beats per minute. Cardiac arrhythmia causes the heart to beat irregularly. Severe cardiac arrhythmia requires immediate medical treatment to avoid serious complications including stroke, heart attack, low blood pressure, and cardiac arrest.
The most common form of cardiac arrhythmia, atrial fibrillation (AF)
, is life threatening when the heart’s upper chambers quiver or beat irregularly and faster than 350 beats per minute. Causes of AF include old age, heart disease, high blood pressure, obesity, and sleep apnea. Over time, unmanaged AF enlarges the upper chamber. Younger adults with thyroid problems are also susceptible to this disease.
“Rapid and irregular heartbeats weaken the heart, which hinders blood circulation,” says Dr. Chotikorn. “This uncirculated blood gets stuck in the upper chamber forming a blood clot, especially in the left atrial appendage, a small, ear-shaped sac in the muscle wall of the heart’s top left chamber. The clot enters the blood stream and clogs blood vessels causing a stroke. Delayed circulation and blood pooling from AF increases the risk of stroke five-fold.”
Left atrial appendage closure to prevent stroke
Medical intervention can prevent strokes and other complications in patients with atrial fibrillation. Initially, doctors perform a thorough diagnostic check to zero in on the exact cause and prescribe medication to regulate heartbeat and reduce blood clot formation. The doctor has two options to prevent further blood clotting:
“Blood thinning medication helps reduce stroke risk in AF, but many patients cannot take it indefinitely because of possible side effects,” says Dr. Chotikorn. “Candidates for left atrial appendage closure may have very low platelet counts, liver failure, renal failure, uncontrolled high blood pressure, and a high risk of brain or unidentified gastrointestinal bleeding, which prevents long-term anticoagulation.”
“In left atrial appendage closure, the doctor inserts a 27mm umbrella-like device with a catheter through the vein at the top of the thigh,” Dr. Chotikorn explains. “The doctor guides the device to the left atrial appendage and when positioned withdraws the catheter, allowing the device to plug and expand to obliterate the space in the appendage. Over time heart tissue grows and seals the area permanently. The procedure takes only around 1-2 hours.”
“Delayed circulation and blood pooling from atrial fibrillation increases the risk of stroke five-fold.” Dr. Chotikorn Khunnawat
The leadless pacemaker, an alternative treatment for a slow heartbeat
A slow heartbeat, also known as bradycardia, is atype of cardiac arrhythmia. Symptoms include dizziness, fatigue, shortness of breath, weakness, low blood pressure, fainting, and cardiac arrest. If severe abnormal cardiac electrical system malfunction causes the condition, the doctor can implant a pacemaker to prevent life-threatening cardiac arrest.
“Pacemaker implants have been in use for more than 50 years,” says Dr. Chotikorn, “it’s inserted under the skin in the upper chest and has leads with sensors at one end. The sensors detect and control the heart’s electrical activity to ensure ample blood supply to the body.”
Conventional cardiac pacemaker implants
can cause several complications, such as hematoma (large bruise caused by bleeding after surgery), pocket infection, visible lump or scar, leads dislodgement and reduced mobility in the shoulder region where the pacemaker resides.
The new leadless cardiac pacemaker is an alternative to traditional pacemakers for the treatment of bradycardia. It’s a self-contained capsule that contains the pacemaker electronics, battery, and leads. It’s 26mm long, 6.7mm in diameter and weighs 1.75 grams. The doctor inserts the device through a catheter threaded through a leg vein to the right ventricle of the heart where it controls the heartbeat.
“The leadless pacemaker is an alternative for some patients who need single chamber ventricular pacing, such as elderly patients or those with chronic atrial fibrillation,” says Dr. Chotikorn. “After the procedure, patients can resume their daily routine with ease and enjoy improved quality of life. However, the leadless pacemaker is not appropriate for all cardiac arrhythmia patients. The doctor will determine whether someone is a candidate.”