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Guidelines for assessing diastolic function by echocardiography are continually being updated. Our ability to use available guidelines effectively has not been completely investigated. Six trained echocardiographers were asked to interpret 105 echocardiograms using current American Society of Echocardiography (ASE) algorithms for interpretation of diastolic grade and estimation of left atrial (LA) pressure. Diastolic grade was categorized as normal, mild, moderate, or severe dysfunction. The presence or absence of elevated LA pressure was determined using a second ASE algorithm. As a reference comparison for level of agreement, left ventricular ejection fraction was visually determined. By the ASE algorithm, 29 subjects (28%) met all measurement criteria in their assigned grade and 57 subjects (55%) met all or all but one criterion of their assigned grade. Of the 45 subjects (43%) for whom the guidelines disagreed by more than 1 criterion, the readers debated between normal and moderate dysfunction in 22% or mild and moderate diastolic dysfunction in 31%. Percent inter-reader agreement and kappa values were 76% (0.7) for determining diastolic grade, 84% (0.67) for determining elevated LA pressure, and 84% (0.67) for estimation of ejection fraction, the reference standard. For all subjects, if multiple echocardiographic criteria failed to fit into the proposed guidelines, agreement fell to 66% (0.58) for determining diastolic grade and 74% (0.48) for determining LA pressure. There is reasonable agreement estimating diastolic grade and LA pressure using current guidelines. Further refinements in the definition of mild and moderate dysfunction may improve agreement.

Background Heart failure in patients with preserved left ventricular systolic function (HFpEF) is a prevalent disease characterized by exercise intolerance, with poorly understood pathophysiology. We hypothesized that recruitable contractility is impaired in HFpEF, accounting for the appearance of symptoms with exertion. Methods and Results Echocardiographic analysis of myocardial performance was performed at baseline and after a modified dobutamine protocol (max dose 16 mcg/kg/min) in participants with known HFpEF and age and sex matched controls. The primary outcome variable was change in contractile reserve, measured as a change in ejection fraction (EF). Recruitable contractility was decreased in HFpEF participants compared to controls (Δ EF HFpEF = 0.4±1.9% vs. control = 19.0±1.4%; p<0.001). During dobutamine infusion velocities increased in control participants but remained unchanged in the HFpEF group, yielding a significant difference between groups (p<0.05) for both longitudinal displacement and velocity. Conclusion Patients with HFpEF have an impaired contractile response to adrenergic stimulation. The blunted response to adrenergic stimulation in the HFpEF group suggests that these patients may be unable to respond to periods of increased cardiac demand. This inability to increase contractility appropriately suggests abnormalities of systolic function in this disease, and may contribute to exertional intolerance in HFpEF.

BACKGROUND The HeartMate II is the most frequently used left ventricular assist device (LVAD) in patients with end-stage heart failure. There is a paucity of data regarding its longitudinal cardiac effects, particularly that on diastole. METHODS This retrospective study was an evaluation of echocardiograms pre-operatively, post-operatively and at 3, 6 and 12 month intervals in patients with a HeartMate II. Measurements included left ventricle (LV) dimensions, ejection fraction (EF), right ventricle (RV) size and function, parameters of diastolic function, analysis of mitral regurgitation (MR), tricuspid regurgitation (TR), aortic insufficiency (AI) and aortic valve thickening. RESULTS Forty-seven patients were evaluated. LV size decreased but EF, RV size and RV function were unchanged. Filling improved with a decrease in central venous pressure (CVP). Right ventricular systolic pressure (RVSP) and diastolic parameters including E/A, deceleration time (DT), pulmonary vein inflow, left atrial size and E/e′ all improved. Ventricular relaxation measured by tissue Doppler (e′) was unchanged. Regarding valve function, MR decreased, TR was unchanged and the aortic valve became increasingly thickened with increased AI severity. CONCLUSIONS The HeartMate II unloads the left ventricle shown by decreased LV size, decreased MR and improved filling. Neither systolic function nor diastolic relaxation improves in this cohort of mostly ischemic cardiomyopathy. RV size and function also remained unchanged. The aortic valve shows deterioration with increased thickening and AI likely from valve fusion. These results improve our understanding regarding the effects of the HeartMate II, particularly that on diastole.

Reduction of the monetary and societal costs of the heart failure epidemic can best be achieved by prevention of new heart failure cases. To effectively prevent heart failure, patients at risk must be identified and treated. The American College of Cardiology/American Heart Association Guidelines for Evaluation and Management of Chronic Heart Failure in the Adult define the stage A heart failure patient as one with identified risk factors for heart failure, particularly coronary heart disease, hypertension, and diabetes, but no evidence of cardiovascular damage. In this review, the authors discuss the commonly recognized, as well as some less commonly recognized, risk factors that define the stage A patient. The authors also discuss data demonstrating that risk factor modification can reduce heart failure incidence. Given the size of the population at risk, through increased awareness of heart failure risk and aggressive treatment, health care providers can critically impact this public health concern.