Hypertension/High Blood Pressure

Hypertension, also known as high blood pressure, is the most commonly diagnosed condition in the United States, affecting more than 74 million US adults - approximately one in three are diagnosed as having hypertension. The global prevalence is more than 1 billion (more than 25% of the adult population) and that rate is forecast to increase over the next decade as demographics shift to an older world population. The economic burden of the disease in the US alone is projected at $76.6 billion this year and $500 billion globally. The number of persons with uncontrolled hypertension in the US has increased from 37 million to 42 million in the decade between 1994 and 2004. Additionally, hypertension plays a major causative role in the development of ischemic heart disease, stroke or cerebrovascular disease, as well as cardiac and renal failure. As such, it is a common risk factor for multiple disease states and has long been a target of intervention. Studies estimate that every 20/10 mmHg increase in blood pressure correlates with a doubling of 10 year cardiovascular mortality.

The earliest evidence for the influence of renal nerve activity in impaired renal function dates to the mid-19th century. Since then, important discoveries in renal physiology have established that increased renal sympathetic nerve activity (RSNA) is an important feature in hypertension. Investigators have subsequently shown in more than a dozen animal models (of experimental hypertension) that renal denervation has completely prevented or delayed the onset of hypertension. The fact that renal denervation has been effective in models of varying origin, and in multiple species, suggests that the renal nerves are importantly involved in the pathogenesis of hypertension. In earlier times, before the availability of antihypertensive drugs, extensive surgical sympathectomy (denervation) was used as a treatment for severe hypertension. In those cases, a survival benefit was demonstrated but the procedures produced high complication rates and morbidity from denervation that did not target the kidney. However, with the advent of drugs, therapies targeting the sympathetic nervous system have been underutilized. Understanding that hyperactivity of renal sympathetic nerves is a major contributor to the progression of the disease, the Company intends to leverage this approach with the benefits of a novel cryoablative technology to ablate the renal sympathetic nerves and thereby lower blood pressure.