After aortic valve replacement, abnormal left ventricular (LV) global longitudinal strain may be a sign of LV dysfunction, a study suggests, even with preserved LV ejection fraction and LV mass regression.
There was much improvement in overall LV global longitudinal strain after valve replacement (-14.8% before versus -17.2% afterwards, P<0.001). Less than a quarter (23.2%) of those who started off with abnormal baseline values maintained that status, with the rest showing normalization.
Milind Y. Desai, MD, of Cleveland Clinic, and colleagues reported online in JAMA Cardiology that on multivariable analysis, deaths and readmission for congestive heart failure over a year’s follow-up were more likely with a worsening Society of Thoracic Surgeons (STS) score (HR 1.06, 95% CI 1.02-1.10) and abnormal postoperative LV global longitudinal strain (HR 2.76, 95% CI 1.40-5.45).
The investigators added that while an improvement by 1% in LV global longitudinal strain value was associated with fewer adverse events over a year (HR 0.92, 95% CI 0.84-0.97), improvement in LV ejection fraction had no such relationship. “Appropriately timed aortic valve replacement relieves left ventricular wall stress and prevents a decline in LV ejection fraction,” the team wrote. “However, despite a preserved LV ejection fraction, there may be irreversible impairment of LV global longitudinal strain postoperatively, with resultant adverse outcomes.
“Whether or not this is due to intrinsic myocardial disease (e.g., myocardial fibrosis) remains to be conclusively established. The data are hypothesis generating and need prospective validation,” they added.
The retrospective study included 208 patients with severe aortic stenosis and preserved LV ejection fraction.
Adding post-operative LV global longitudinal strain values to STS scores provided better prognostic utility, with the C statistic of the STS model rising from 0.61 to 0.69 upon addition (P<0.01).
Desai reported no relevant conflicts of interest.
Kafa R, et al “Association of abnormal postoperative left ventricular global longitudinal strain with outcomes in severe aortic stenosis following aortic valve replacement” JAMA Cardiol 2016; DOI: 10.1001/jamacardio.2016.1132.