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Systolic BP Targets Should Probably Be Higher in Early Aortic Stenosis

      ORLANDO — Optimal blood pressure in patients with asymptomatic mild to moderate aortic stenosis is 140–159 mm Hg for systolic and 70–89 mm Hg for diastolic, according to an analysis of all-cause mortality in the world's largest data set of such patients with longitudinal follow-up and endpoint evaluation.
      Within those target blood pressure ranges, the nadir in terms of all-cause mortality is about 145/82 mm Hg, Kristian Wachtell, MD, PhD, reported at the American Heart Association scientific sessions.
      He presented an analysis of 1,873 asymptomatic patients with mild to moderate aortic stenosis (AS) and a peak aortic-jet velocity of 2.5–4.0 m/s upon enrollment in the Simvastatin Ezetimibe in Aortic Stenosis (SEAS) trial. SEAS was a double-blind, multicenter study in which participants were randomized to 40 mg of simvastatin plus 10 mg of ezetimibe per day or placebo and followed for a mean of 4.3 years. Half of them had a history of hypertension at baseline.
      As previously reported (N Engl J Med 2008;359:1343–56), SEAS was a negative trial. Lipid-lowering therapy didn't affect AS progression or aortic valve–related outcomes. On the plus side, the SEAS cohort is the world's largest population of patients with asymptomatic AS followed prospectively for clinical endpoints, noted Dr. Wachtell of Oslo University.
      'I think it's most likely that for blood pressure, one size does not fit all. ... The extent of target organ damage ... warrants a different level of blood pressure.'
      He and his coinvestigators decided to plot all-cause mortality vs. average blood pressure in the SEAS cohort because of the paucity of data regarding blood pressure and antihypertensive therapy in patients with asymptomatic AS. Neither the 2014 ACC/AHA guidelines for management of valvular heart disease (Circulation 2014;129[23]:e521–643) nor the European guidelines provide recommendations for optimal blood pressure targets in patients with asymptomatic AS, even though AS is the third most common cardiac disease, behind hypertension and coronary artery disease.
      Moreover, nearly 100,000 aortic valve replacements are done per year in the United States as a consequence of AS. And AS and hypertension go hand in hand, with the prevalence of hypertension among patients with AS cited as 50% or more in multiple studies, the cardiologist continued.
      In a multivariate analysis adjusted for aortic valve area index and peak velocity, heart failure, myocardial infarction, and aortic valve replacement during follow-up, all-cause mortality showed a U-shaped relationship with blood pressure. A systolic blood pressure below 120 mm Hg was associated with a 5-fold increased risk of mortality, a systolic of 120–139 mm Hg carried a 1.5-fold increased risk, and a diastolic blood pressure of 90 mm Hg or more was associated with a 1.9-fold increased risk.
      “Patients with low systolic blood pressure had an increased mortality risk and should probably undertake individual clinical assessment for blood pressure control and evaluation of their AS,” Dr. Wachtell said.
      The first question audience members asked was, “What about SPRINT?” The SPRINT trial, presented elsewhere at the meeting, was a practice-changing study that was the talk of the conference. It redefined the systolic blood pressure treatment target as less than 120 mm Hg instead of less than 140 mm Hg in hypertensive patients (N Engl J Med 2015;373:2103–16).
      “I think it's most likely that for blood pressure, one size does not fit all,” Dr. Wachtell replied. “The extent of target organ damage — and you could say that aortic stenosis is actually target organ damage, like atrial fibrillation or left ventricular hypertrophy — warrants a different level of blood pressure.”
      He added, however, that the SEAS analysis was based on observational data, and that's a limitation.
      “This is a qualified guess as to what blood pressures should be in patients with aortic stenosis,” he cautioned.
      Dr. Wachtell reported having no conflicts of interest regarding his presentation.
      Bruce Jancinis with the Denver bureau of Frontline Medical News.