RV strain analysis improves risk predictions for acute decompensated HF
Right ventricular (RV) strain analysis could be a useful addition to existing methods of risk assessment in patients with acute decompensated heart failure (ADHF), according to recent research that identified RV longitudinal strain from the free wall (RV-fwLS) as an independent predictor of cardiac events in the demographic.
Heart failure patients, despite the advent of numerous evidence-based medical therapies, continue to face poor prognoses and high rates of repeat hospitalization, corresponding author Yoshihiro Seo, MD, PhD, and colleagues wrote in Circulation: Cardiovascular Imaging. As a result, techniques like two-dimensional strain analysis based on speckle tracking echocardiography (STE) have emerged and successfully been used to detect myocardial deformation.
“Although two-dimensional strain analyses based on STE have been used to detect myocardial deformation, the prognostic impact of two-dimensional strain is unclear in patients with ADHF,” Seo, of the University of Tsukuba in Japan, and co-authors said. “We investigated whether left ventricular (LV) and right ventricular strain parameters assessed by STE provide incremental prognostic information in patients hospitalized because of ADHF.”
Seo’s team studied 618 patients consecutively hospitalized due to ADHF, the majority of whom were men and in their late 60s and 70s. All patients, who recorded an average 46 percent ejection fraction at the study’s baseline, underwent clinical and echocardiographic evaluation before their discharge.
The researchers performed strain analyses of LV global longitudinal strain and LV global circumferential strain—two important prognostic indicators for HF that have rarely been studied in the ADHF population.
The team also analyzed RV-fwLS and RV strain from all segments of the longitudinal strain wall. After a median follow-up of 427 days, 34.8 percent of the study population met Seo et al.’s primary endpoint of cardiovascular death or readmission for HF.
Of the parameters studied, just RV-fwLS seemed to have any influence on HF outcomes, the authors reported. It was independently associated with a 1.5-fold increased risk of cardiac events, and adding it to traditional risk evaluation factors—like age, New York Heart Association class, blood urea nitrogen and brain natriuretic peptide—improved prognostic utility. When combined with those other indicators, RV-fwLS values increased net reclassification improvement in the population by 30 percent.
“Among left ventricular and RV strain parameters, only RV-fwLS has an incremental value to identify the ADHF patients at high risk after discharge,” Seo and colleagues wrote. “Therefore, ADHF patients with impaired RV-fwLS at discharge should require close outpatient follow-up and more aggressive medical treatment to avoid cardiovascular events.”
In a related editorial, University Hospitals Cleveland Medical Center physician Brian D. Hoit, MD, said Seo et al.’s study adds to the literature on a scarcely studied subject, but it also raises a number of questions.
“First, what clinical, laboratory and echocardiographic variables should be used to risk stratify patients with ADHF (i.e., what increment of prediction is worth the additional expense and effort), and at what point of their hospitalization should testing be performed?” he wrote. “What is the optimal statistical method in which to measure a true improvement in prognostic accuracy?
“And perhaps most importantly, how can the ability to identify a cohort of HF patients at risk for cardiac death and rehospitalization be leveraged to intervene with both pharmacological and advanced therapies?”
Hoit said Seo and colleagues’ work has theoretical advantages, but realistically deformation analysis requires a lot of time, effort and expertise. Variable partition values, variability in values between STE algorithms, ever-changing software and a lack of normative values are all barriers to the use of strain imaging.
“Notwithstanding a compelling body of data, risk stratification and decision-making strategies incorporating RV strain are not currently exploited in routine clinical practice,” Hoit said. “The study by Seo et al. provides a needed step that supports incorporation of RV strain into risk prediction that hopefully...will lead to an action of consequence.”
After graduating from Indiana University-Bloomington with a bachelor’s in journalism, Anicka joined TriMed’s Chicago team in 2017 covering cardiology. Close to her heart is long-form journalism, Pilot G-2 pens, dark chocolate and her dog Harper Lee.