Memorial Hermann is the first hospital system in Houston to use catheters with direct contact force technology for the treatment of patients with atrial fibrillation (Afib), a common heart rhythm disorder.
Recently approved by the U.S. Food and Drug Administration, the ThermoCool® SmartTouch® Catheter enables doctors to more accurately control the amount of contact force applied directly to the heart wall during radiofrequency catheter ablation procedures. This can increase the effectiveness and safety of the procedure for patients.
“During cardiac ablation, an electrophysiologist tries to isolate the area of the heart where atrial fibrillation originates so the heart can return to a normal rhythm,” said Ramesh Hariharan, M.D., director of cardiac electrophysiology at Memorial Hermann-Texas Medical Center and professor of medicine at the University of Texas Medical School at Houston.
Hariharan continued, “Maintaining close contact with the tissue and knowing how much pressure you are applying against the heart wall ultimately means better outcomes for the patients. Before, doctors had to estimate the amount of force applied to the heart wall through other indirect measures shown not to be as effective.”
During a minimally invasive catheter ablation procedure, doctors insert a therapeutic catheter (long, flexible tubes) through a small sheath in the groin, where it is then guided into the heart through a blood vessel. Once it reaches the left upper chamber of the heart (atrium), the catheter delivers radiofrequency energy to the heart wall to create lesions that block faulty electrical impulses causing heart rhythm disorders.
Providing doctors with the ability to apply stable contact force during catheter ablation has been shown to improve patient outcomes, as poor tissue contact force may result in incomplete lesion formation. When lesions do not form properly during the procedure, additional treatment may be necessary to correct the patient’s atrial fibrillation. On the other hand, too much contact force may damage the tissue and cause other complications.
The results from a clinical trial that studied the safety and effectiveness of this new device showed, after one year, patients experienced a 74 percent success rate after treatment. More importantly, data from the trial showed higher success rates the longer physicians stayed within a targeted contact force range, with one-year results demonstrating an 88 percent success rate when physicians stayed within a targeted range 85 percent of the time or more.
“The burden of atrial fibrillation on quality of life, morbidity, and mortality is well-documented,” said Hariharan. “The use of contact force-sensing technology has emerged as a critical tool in delivering optimal outcomes in the treatment of patients with atrial fibrillation and represents a major advancement for the clinical community.”
Dr. Hariharan, Rajesh Venkataraman, MD and Senthil Thambidorai, MD have performed multiple procedures using this new technology at Memorial Hermann The Woodlands Hospital.
With care that ranks in the top 1 percent of hospitals nationally and Joint Commission accreditation for Acute Myocardial Infarction and Heart Attack treatment, the Complex Arrhythmia Program at Memorial Hermann The Woodlands offers expert care for patients with heart arrhythmias. The complete range of treatment options includes drug therapy and minimally invasive surgical ablation.
An estimated 3 million Americans suffer from atrial fibrillation, a progressive disease that increases in severity and frequency if left untreated, and can lead to chronic fatigue, congestive heart failure, and stroke. While most atrial fibrillation patients today are treated with drugs, about half of patients are not able to control their abnormal heart rhythm with drugs or find they cannot tolerate the side effects. When medication proves to be unsuccessful, the American College of Cardiology and the American Heart Association suggest catheter ablation be considered as a safe and effective treatment option. Clinical studies show that success rates for atrial fibrillation treatments such as catheter ablation decrease the longer the disease is left untreated so earlier intervention is recommended.