Factors Associated with Low Flow in Aortic Valve Stenosis.

BACKGROUND: Low-flow low-gradient aortic stenosis (AS) is a predictor of worse outcome compared with normal-flow AS. Although depressed left ventricular ejection fraction (LVEF) is associated with low flow, there is less evidence to support the role of other indices of cardiac structure and function. METHODS: Clinical and echocardiographic data from patients with native AS and valve areas ≤ 1.0 cm(2) were retrospectively analyzed to identify characteristics that are associated with low-flow low-gradient AS. RESULTS: In total, 941 patients were included. On multivariate analysis, factors independently associated with low flow (stroke volume index < 35 mL/m(2)) included worse right ventricular systolic function, atrial fibrillation, lower LVEF, and higher left ventricular mass, with moderate or severe mitral regurgitation independently associated with low flow in the 694 patients (74%) with preserved LVEFs. CONCLUSIONS: Right ventricular dysfunction and atrial fibrillation are independently associated with low-flow low-gradient AS, while moderate or severe MR is independently associated with low flow in patients with preserved LVEF. These associations with low flow in AS are clinically important to recognize, to avoid underestimation of AS severity.

Management of risk factors among ambulatory patients at high cardiovascular risk in Canada: a follow-up study.

BACKGROUND: Limited longitudinal data are available on attainment of guideline-recommended treatment targets among ambulatory patients at high risk for cardiovascular events. METHODS: The Vascular Protection registry and the Guidelines Oriented Approach to Lipid Lowering registry recruited 8056 ambulatory patients at high risk for, or with established cardiovascular disease; follow-up was not protocol-mandated. We stratified the study population according to the availability of 6-month follow-up data into 2 groups, and compared their clinical characteristics, medication profile, and attainment of contemporaneous guideline-recommended blood pressure (BP) and lipid targets both at enrollment and at 6-month follow-up. RESULTS: Of the 8056 patients, only 5371 (66.7%) patients had 6-month follow-up, who had significant increases in the use of statins and antihypertensive medications at 6 months compared with at enrollment (all P < 0.001). Compared with at time of enrollment, more patients attained the BP target (45.3% vs 42.3%), low-density lipoprotein cholesterol (LDL-C) target (62.8% vs 45.8%), and both targets (29.7% vs 21.6%) at 6-month follow-up (all P < 0.001). In multivariable analysis, independent predictors of attainment of BP target included history of coronary artery disease and heart failure (all P ≤ 0.001). On the other hand, advanced age, diabetes, coronary artery disease, previous coronary revascularization, and use of statin therapy were independently associated with achievement of LDL-C target (all P < 0.005). CONCLUSIONS: Most (> 50%) patients without 6-month follow-up did not attain guideline-recommended BP and LDL-C targets at enrollment. Although BP and lipid control improved at 6 months among patients with follow-up, most still failed to achieve optimal BP and lipid targets. Effective ongoing quality improvement measures and follow-up are warranted.