1 Clinical Trials for Various Conditions
As we live longer our population experiencing heart failure (HF) continues to grow consuming an increasing percent of healthcare dollars. Systolic heart failure or pump failure is easy to recognize and measure and is expressed as ejection fraction. Diastolic heart failure (DHF) or failure to fill adequately is much more difficult to quantify with no single measure or number being used to express the severity instead groupings are used with normal and Grade I, II or Grade III to classify with Grade III being the direst. Heart Failure with Reduced Ejection Fraction (HFrEF) and Heart Failure with Preserved Ejection Fraction (HFpEF) are used to identify the primary clinical presentation of HF but do not adequately describe the combined effect often presenting within the same subject. It is estimated 35 to 50% of those with HFrEF, having Left Ventricle Ejection Fraction (LVEF) \< 50%, and 50 to 70% of those with HFpEF, having ejection fraction ≥ 50%, also have moderate to severe diastolic dysfunction (DD). The purpose of this study is two fold. The first is to determine if the rate of change measured from the left ventricular inflow inspiratory phase Doppler waveform provides insight into a cause of diastolic heart failure by comparing echocardiographic data points obtained prior to and immediately following optimization of a bi-ventricular pacemaker. This HF population requires an ejection fraction of 35 percent or lower to qualify for the device. These echocardiograms have been previously completed and will be reanalyzed. The second purpose is to determine if relationships between different features of a LV volume curve can be used to generate a single number to describe global diastolic function using the same echocardiograms from the pacemaker group. Results will be compared to a small group of healthy normal participants as a control for validation.