Showing papers by "Joseph L. Izzo published in 2016"

Controversies in hypertension: is lower blood pressure always better?

Abstract: Cardiovascular disease risk is continuously related to BP over the range of about 115/75 to 185/115 mmHg, yet all clinical guidelines use arbitrary cutoffs to determine acceptable antihypertensive therapy. There is substantial conflict in the results of clinical trials with respect to how low the most appropriate BP threshold should be to reduce CVD and renal risk. This divergence should not be surprising given the intrinsic differences in circulatory anatomy and physiology among the heart, brain, vessels, and kidney. In the real world, however, discreet BP targets or even ranges may be a tolerable practical necessity as long as it is recognized that any arbitrary threshold in a continuous relationship can serve as both a stimulus and a barrier to effective treatment. Overall, it may be necessary to assess risk differentially by organ or disease process; lower systolic pressure is most beneficial in preventing recurrent stroke and heart failure episodes, benefits on kidney function and ischemic heart disease are less demonstrable for a variety of scientific and experimental design reasons. It may also be a good time for practice guideline writers and individual physicians to re-evaluate the benefits of lower BP targets.

Should age determine hypertension management? Recommendations from current guidelines.

Abstract: Age is the most powerful of risk factors and is related continuously to systolic BP and cardiovascular disease risk. Yet current guidelines have dichotomized age groups around a cutoff value of 55-60 years and some guidelines now suggest that age should affect diagnostic thresholds and drug choices. These choices are not supported directly by scientific evidence but are based on expert opinion, the value of which is uncertain. This initial topic of the new Controversies in Hypertension series highlights important differences among current U.S., European, and Canadian practice guidelines, then moves on to editorial commentaries with different perspectives.

Renal denervation for human hypertension: is there a future?

Abstract: The sympathetic nervous system plays a permissive, if not primary causal role in the genesis and maintenance of human essential hypertension. Excessive sympathetic nervous system activity in man is most apparent in early forms of hypertension (prehypertension and white-coat type). Renal nerves are of particular interest because of their roles in modulating the activity of the renin-angiotensin system and renal sodium excretion. Renal denervation substantially ameliorates the development of hypertension in animal models such as renovascular, spontaneously hypertensive, and steroid-induced hypertension in rats and aortic coarctation in dogs. In man, catheter ablation of renal nerves has been undertaken in the late phases of hypertension; in a rigorously controlled trial in resistant hypertension (SYMPLICITY HTN-3), renal denervation did not reduce blood pressure over the long term. Is this because renal denervation is more appropriate to prevent than treat late-stage hypertension? Are there anatomical or technical barriers yet to be overcome in the procedure? These and other issues are addressed by two experts in this issue of the controversies series: Deepak L. Bhatt and Murray Epstein.