Results of a new study indicate an unrecognized systolic dysfunction.
Many patients hospitalized for acute heart failure with preserved ejection fraction (HFpEF) have abnormal left ventricular global longitudinal strain (LV GLS), a recent study suggests.
These results may indicate an unrecognized systolic dysfunction, according to Jonathan Buggey, MD, and researchers at Duke University Hospital, who authored the study.
Patients with HFpEF represent about 50% of the total with clinical heart failure, and following the first hospitalization the mortality rates for patients with HFpEF and those with heart failure with reduced ejection fraction (HFrEF) are about the same, around 43%. However, there are currently no therapies that have been proven to reduce hospitalization rates nor mortality rates in patients with HFpEF as there are for those with HFrEF, mostly because HFpEF is complex and the pathophysiology of the condition is poorly understood.
In addition to a poor understanding of the complex pathophysiology of acute HFpEF, few tools exist to stratify the patient population. Left ventricular ejection fraction (LVEF) may be normal in HFpEF patients, and those patients may also have unrecognized systolic dysfunction. The researchers suggest that the lack of stratification tools combined with the poor understanding of how the condition occurs led them to conduct the current study.
“We investigated the association of LV GLS on 30-day and 1-year mortality and rehospitalizations and describe the prevalence and distribution of abnormal LV GLS,” they said in describing their retrospective study of patients who had been hospitalized with acute HFpEF and who needed diuretic treatment.
The study population was drawn from patients admitted to Duke University Medical Center between 2007 and 2010. All participants had a 2D transthoracic echocardiogram at some point in their hospital stay and were discharged taking a loop diuretic, either furosemide or torsemide. The primary outcome for this study was all-cause mortality from 30-days and 1-year following discharge. The researchers also considered rehospitalization within the Duke University Health System as a secondary outcome of interest.
The cohort for this study consisted of 463 patients, of whom 24% had normal LV GLS, while 76% had impaired LV GLS. In an unadjusted analysis, the researchers report finding no statistically significant association between LV GLS and mortality at either 30-days or 1-year after discharge. When they adjusted for comorbidities they found patients with LV GLS had significantly worse outcomes at 30-days post discharge, but not 1 year.
Interestingly, the researchers note, “although HFpEF patients are more likely to be women, we found a higher proportion of men with abnormal LV GLS among those with acute HFpEF.” Previous studies had similar findings and the researchers suggest further studies into what they describe as a “unique association” are warranted.
Being a single-center study is a limitation of this investigation, and the authors acknowledge that while they adjusted for variables that were likely to affect mortality, other variables could have contributed to the results in unknown ways. For example, patients included in this study likely had different therapies such as diuresis prior to evaluation.
“LV GLS may be a useful tool for identifying a cohort of HFpEF patients with more overt myocardial dysfunction who are at risk for worse outcomes following a hospitalization for HF,” researchers said, prior to concluding that additional studies are necessary to determine whether therapies targeting myocardial function would be effective in cases of acute HFpEF with abnormal LV GLS.
The full study is available in the journal ESC Heart Failure.
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