St. Jude Medical Enrolls First Patient in Renal Denervation Study

St. Jude Medical Inc. has enrolled the first patient in the EnligHTN II trial, which is aimed at further evaluating the safety and efficacy of the EnligHTN renal denervation system in patients with uncontrolled hypertension. According to the World Health Organization, one in three adults worldwide has elevated blood pressure—a condition that increases the risk of heart attack, stroke and kidney failure.

Renal denervation is a catheter-based ablation procedure that potentially provides lasting reduction in blood pressure for patients with resistant hypertension. A catheter is introduced through the femoral artery in the leg to access the renal arteries that connect to the kidneys, where radiofrequency energy is delivered to create lesions (tiny scars) along the renal sympathetic nerves—a network of nerves that help control blood pressure. This intentional disruption of the nerve supply causes systolic and diastolic blood pressure to decrease.

The EnligHTN II (international, non-randomized, single-arm, long-term follow-up study of patients with uncontrolled hypertension) trial expands upon the research conducted in the EnligHTN I trial, which demonstrated that patients with drug-resistant hypertension treated with the St. Jude Medical EnligHTN system had a rapid and sustained drop in blood pressure. After 30 days, systolic blood pressure was reduced by an average of 28 mmHg (millimeter of mercury) that remained stable with a reduction of 26 mmHg points six months after treatment, an important finding as the risk of cardiovascular death drops by half with every systolic decrease of 20 mmHg.

The EnligHTN system is a multi-electrode ablation technology that features a non-occlusive basket design that, according to St. Jude, delivers a predictable pattern of four evenly spaced ablations with each catheter placement. This ostensibly allows for continuous blood flow to the kidney during the procedure. Compared to single-electrode ablation systems, the multi-electrode EnligHTN system has the potential to improve consistency and save time, which may result in improved workflow and cost efficiencies.

The renal denervation technology includes a guiding catheter, ablation catheter and ablation generator. The generator uses a proprietary, temperature-controlled algorithm to produce effective lesions. Additionally, minimal catheter repositioning may result in a reduction of contrast and fluoroscopic (X-ray) exposure.

“There is convincing evidence from studies like the EnligHTN I trial linking renal denervation to improved blood pressure in patients who have drug-resistant hypertension,” said Johannes Brachmann, M.D., at Klinikum Coburg in Coburg, Germany. “Expanding this research to patients with less severe forms of hypertension is important as this minimally invasive approach allows for a shorter procedure time and a potentially faster recovery time, which may benefit more patients with uncontrolled hypertension.”

Hypertension occurs when blood pressure in the arteries is elevated, requiring the heart to work harder than normal to circulate blood throughout the body. A typical normal blood pressure reading is below 120 systolic and 80 diastolic—expressed as 120/80 mmHg. To date, the majority of renal denervation studies have only tested the safety and efficacy of this technology in patients with drug-resistant hypertension, which is defined as systolic blood pressure above160 mmHg, despite being on three or more anti-hypertensive medications including a diuretic.

The goal of the EnligHTN II study is to broaden this scope by evaluating the mean reduction in systolic blood pressure at six months across all enrolled patients post renal denervation and within sub-groups with varying degrees of kidney functionality. The study will be conducted at 40 sites in Europe and Australia and will enroll approximately 500 patients with uncontrolled hypertension.

In 2012, The EnligHTN Renal Denervation System earned European CE Mark approval and was launched in several markets. It is not yet approved for use in the United States.

“St. Jude Medical is dedicated to conducting research that will contribute to the body of evidence supporting the effectiveness of renal denervation in reducing hypertension,” said Frank J. Callaghan, president of the St. Jude Medical Cardiovascular and Ablation Technologies Division. “Through the course of the EnligHTN II study, we expect to gain additional insights into the benefits and sustainability of blood pressure reductions achieved through use of the EnligHTN Renal Denervation System in an expanded patient population.”

St. Jude is headquartered in St. Paul, Minn.