Medical Device Daily

St. Jude Medical (St. Paul, Minnesota) reported introducing a new feature into its cardiac rhythm product offerings to help treat patients with heart failure (HF).

The company said it received FDA approval of a new cardiac rhythm management device — called the Atlas II+ HF CRT-D (cardiac resynchronization therapy defibrillator) — designed to help physicians manage heart failure (HF) patients, including patients who have or may develop atrial fibrillation (AF).

The company said the device is the first U.S. HF system to offer the AF Suppression algorithm. This algorithm helps maintain control of the heart's atrial rhythm by pacing slightly faster than the patient's natural heart rate. The AF Suppression algorithm has been clinically proven to reduce the AF burden (the percentage of days with AF symptoms) in previous studies.

According to company spokesperson Kathleen Janasz, the AF burden was determined by measuring the percentage of days over a period of six months that patients experienced AF symptoms during clinical trials for the system.

"In this trial, it was proven that the AF Suppression algorithm actually reduced the AF burden in the patients in these studies," Janasz told Medical Device Daily.

Heart failure and AF — considered the two new and growing epidemics of cardiovascular disease — commonly occur together. About 40% of patients who have HF also experience AF, according to the 2003 Framingham Heart Study, and the incidence of AF appears to increase as the severity of HF increases. Nearly 5 million Americans have HF, according to the American Heart Association (Dallas).

AF is the most common abnormal heart rhythm. It is characterized by a very fast, uncontrolled heart rhythm caused when the upper chambers of the heart (the atria) quiver instead of beat. Because the pumping function of the upper chambers isn't working properly, the blood is not completely emptied from the heart's chambers, resulting in reduced cardiac output.

Janasz noted that at one time not long ago, AF wasn't considered to be a very big deal for patients — it was something they just had to live with.

"That's no longer true at all," she said. "What happens is that when blood pools in the heart, it increases the risk of stroke and it also can lead to other kinds of arrhythmias. These patients are [also] at risk of sudden cardiac death, which kills 350,000 people a year just in this country alone."

The company noted that heart failure patients with AF present significant challenges, such as further reduction in cardiac output, potential loss of biventricular pacing (if the abnormal rhythm is conducted rapidly or irregularly to the ventricles) and increased risk of stroke. Managing these conditions can be complicated by the fact that many patients already are on extensive drug regimens, and they often have other health issues.

The new Atlas II+ HF CRT-D also offers the company's QuickOpt timing cycle optimization feature, a programmer-based optimization for people with CRT-D devices and traditional implantable cardioverter defibrillators that helps physicians quickly program the device's timing so it delivers optimal therapy to patients. The QuickOpt feature produces results that are comparable to echocardiography, but is significantly less costly and time-consuming, the company said.

A QuickOpt timing cycle optimization procedure takes less than two minutes, while a typical echo procedure takes between 30 and 120 minutes and requires manual interpretation by a technician.

The QuickOpt feature electrically characterizes the conduction properties of the heart and uses an algorithm to calculate the optimal timing values. This allows for more efficient and frequent optimization during routine device follow-up visits.

The device can be remotely monitored, which enables information to be downloaded and accessed from any computer with Internet access, enabling routine follow-up to be conducted from the convenience of the patient's home.

"Because heart failure patients often have other health issues, we have added the AF Suppression algorithm to the Atlas II+ HF CRT-D to help physicians better manage this complicated comorbidity," said Michael Coyle, president of St. Jude Medical's Cardiac Rhythm Management Division.

"This technology provides another tool for physicians to tailor treatment to specific and complex patient conditions."