Assessing the Link Between Myocardial Blood Flow Reserve With Adverse Left Ventricular Remodeling in Aortic Stenosis

A new study published in JAMA Cardiology found that aortic stenosis (AR),  Impaired myocardial flow reserve (MFR), as well as stress myocardial blood flow (MBF) are all associated with adverse myocardial characteristics. The findings indicate that that these indices may serve as early sensitive markers of left ventricular decompensation.

In this single-center prospective observational study, which took place from 2018 to 2020, the investigators assessed 34 patients with AS (1 mild, 9 moderate, and 24 severe), as well as 34 matched controls with predominantly moderate to severe AS who underwent ammonia N13 PET myocardial perfusion imaging.

The primary outcome was defined as LV structure and function parameters, including echocardiographic global longitudinal strain (GLS), circulating high-sensitivity troponin T (hs-cTnT), N-terminal pro–B-type natriuretic peptide (NT-pro BNP), health status, and functional capacity.

According to the results, MFR was independently associated with GLS and LV ejection fraction, (β,−0.31; P = .03; β, 0.41; P = .002, respectively), while stress MBF was linked with hs-cTnT (unadjusted β, −0.48; P = .005) and log NT-pro BNP (unadjusted β, −0.37; P = .045). The researchers noted that the combination of low stress MBF and high hs-cTnT was associated with higher interventricular septal thickness in diastole, relative wall thickness, and worse GLS compared with high stress MBF and low hs-cTnT (12.4 mm vs 10.0 mm; P = .008; 0.62 vs 0.46; P = .02; and −13.47 vs −17.11; P = .006, respectively).

 

“In this study, in AS, MFR and stress MBF were associated with adverse myocardial characteristics, including markers of myocardial injury and wall stress, suggesting that MFR may be an early sensitive marker for myocardial decompensation,” the researchers concluded.