At first pass, lariat seems like just a hifalutin' wordfor the more down-to-earth, lasso – along, noosed rope. For most, either word will bring to mind images of cowboysand rodeos, not human hearts. However, thanks to a new technology making itsway onto the medical scene, lariat has a new meaning and is helping to treatthe most common of cardiac arrhythmias, atrial fibrillation.
Let’s take a few steps backthough, before we make the leap from rodeo ring to hospital.
Atrial fibrillation (AFib) is anirregular heartbeat that feels like a fluttering or quivering of the heart thataffects close to three million Americans. According to the National Heart, Lungand Blood Institute, when AFib occurs, rapid, disorganized electrical signals causethe heart’s two upper chambers to fibrillate, or contract very quickly andirregularly.
AFib causes blood to pool in theupper chambers of the heart. This keeps the heart from pumping blood completelyinto the heart’s two lower chambers. While for some, the symptoms of AFib canfeel very frightening, others have no signs at all. But symptomatic or not,make no mistake about it: AFib is not a simple “heart flutter” and certainlynot something to ignore. The biggest threat from atrial fibrillation is thethreat of blood clots and stroke.
“Patientswith atrial fibrillation are six times more at risk of having a stroke and 15 to 20 percentof all strokes a year are related to AFib,” said Daniel J. McCormick, DO, FACC, FSCAI, an interventional cardiologist at Pennsylvania Hospital. “This is not onlysignificant from a direct health care standpoint, but a societal one as wellsince stroke is one of the biggest drivers of disability and health care costsin the U.S.”
The standard treatment forAFib is the use of anticoagulants, more commonly known as blood thinners, suchas warfarin, and heparin. While there will always be a need for blood thinnersin medicine, the truth is, their effectiveness is precisely what makes them sodangerous. Warfarin, the most commonly used for example, is also used to poisonrats and mice. Its anti-clotting properties produce death through internalhemorrhaging – a trait you want to control rodent populations, not your AFib.
This is why warfarin isconsidered a “black box drug” by the U.S. Food and Drug Administration (FDA).The black box is the strictest warning the FDA can give a medicine while stillpermitting it to remain on the market. According to Dr. McCormick, patients onblood thinners must be monitored weekly to make sure their medication levelsare safe, which limits one’s mobility and quality of life. Striking a balancebetween effective, therapeutic levels of blood thinners and hazardous ones isdelicate and requires constant diligence on part of both the patient andphysician – a level of diligence many patients aren’t capable of maintaining.“Even with careful monitoring only about 20 percent of all patients on warfarinare within the proper range at any one given time,” explained Dr. McCormick.“These patients are living on a very short leash.”
According to McCormick, hereinlies a primary challenge of treating patients with AFib: there is a real need for other therapies totreat patients that:
1) Have a prior history of stroke and can’t take anti-coagulantsbecause of bleeding complications.
2) Are extremely difficult to manage despite diligence andmonitoring.
More invasive treatments forAFib include implants (currently still in clinical trials) and surgery to placesutures, clips and staples to close off the affected trouble areas of theheart.
A little less invasive in thatit doesn’t leave anything in the heart, is radiofrequencyablation, where a small, flexible catheter is inserted through a vessel inthe groin and up to the heart. Using fluoroscopy, a live x-ray image, aninterventional cardiologist carefully guides the catheter up into the heartwhere small electrodes are placed. The electrodes, connected to monitors tohelp locate what exact areas of the heart are causing the AFib, are also usedto send electrical energy to the problem areas, effectively destroying them andcreating a tiny bit of scar tissue. It’s the scarring that halts the irregularheart rhythm. While ablation can often control AFib and many patients do well,it’s not full-proof. “There’s a high recurrence rate of AFib in ablationpatients – about 30 percent,” said Dr. McCormick.
Enter the lasso! Or morespecifically, PLACE™ a LARIAT®. By using the PLACE procedure of PermanentLigation Approximation Closure and Exclusion, a physician is able deploy theLARIAT, an FDA-approved Left Atrial Appendage Occlusion Device, to seal off themalfunctioning area of the heart where dangerous blood clots can form.
Dr. McCormick performed thefirst two LARIAT cases on January 30, at Pennsylvania Hospital, the first inthe region to use the new technology and second in the state.
Performed in the hospital’s cardiaccatheterization lab, the procedure takes approximately two hours with a patientunder general anesthesia. Two small catheters are threaded through the groin upto the heart allowing for two magnetic tipped wires to hold the affected areain place. Then a balloon is inflated to confirm the proper position of the areato be sutured off with a micro-mini lasso. The suture/lasso/lariat is thencinched up around the base of the appendage, sealing off the problem area.After a year, the whole affected area just naturally withers away to nothing.While still in the early stages of employment, previous use so far suggeststhere are low complications and a high success rate associated with theprocedure.
Patients are required to stay on bed restfor four hours once out of recovery and stay over the night in the hospital.“The LARIAT provides a permanent solution for stroke risk associated withatrial fibrillation without leaving any devices or other objects behind in theheart.” said McCormick. “But what’s really exciting is that the patient is offwarfarin immediately after the procedure. It’s terrific to be able to addanother tool to our arsenal of treatments for atrial fibrillation.
Wantto learn more about reducing your risk for heart disease this? Visit the Penn Heart and Vascular update on Penn Medicine’s website.