Wright, L and Negishi, K and Dwyer, N and Wahi, S and Marwick, TH, Afterload Dependence of Right Ventricular Myocardial Strain, Journal of the American Society of Echocardiography, 30, (7) pp. 676-684. ISSN 0894-7317 (2017) [Refereed Article]
METHODS: Sequential echocardiograms were collected retrospectively at two time points between 2005 and 2015 in 187 patients (71% women; mean age, 63 ± 14 years) undergoing pulmonary vasodilator therapy for group 1 PAH. Patients were either studied during PAH therapy (n = 111) or before and after treatment initiation (n = 76). Standard measurements of RV and left ventricular function and PASP were performed, and speckle-tracking strain was used to calculate RVFWS. The linear response of RVFWS to afterload (PASP) was assessed using a standard regression equation. Because it is unclear if the response might be nonlinear, a quadratic association (PASP squared) was also used in the regression model.
RESULTS: At visit 1, patients with PAH showed impaired functional capacity (mean 6-min walk distance, 371 ± 131 m), increased PASP (mean, 54 ± 26 mm Hg), and borderline RVFWS (mean, 18 ± 6%). Patients before PAH therapy showed more pronounced reduction in 6-min walk distance (mean, 302 ± 136 m) and RVFWS (mean, 16 ± 5%). RVFWS at baseline was associated with PASP (R2 = 0.25, P = .001), RV end-diastolic area (R2 = 0.36, P < .001), and fractional area change (R2 = 0.21, P < .001). Change in RVFWS was more strongly associated with ΔPASP (std β = -0.20, P = .02) than ΔPASP squared (std β = 0.11, P = .20). RVFWS showed strength over fractional area change for sequential RV assessment over a range of PASP changes.
CONCLUSIONS: Afterload changes should be taken into account in the evaluation of RVFWS during PAH follow-up, with the relationship to PASP likely to be linear.
|Item Type:||Refereed Article|
|Keywords:||Fractional area change, Pulmonary artery systolic pressure, Right ventricle, Strain|
|Research Division:||Medical and Health Sciences|
|Research Group:||Cardiorespiratory Medicine and Haematology|
|Research Field:||Cardiology (incl. Cardiovascular Diseases)|
|Objective Group:||Clinical Health (Organs, Diseases and Abnormal Conditions)|
|Objective Field:||Cardiovascular System and Diseases|
|Author:||Wright, L (Ms Leah Wright)|
|Author:||Negishi, K (Dr Kazuaki Negishi)|
|Author:||Marwick, TH (Professor Tom Marwick)|
|Deposited By:||Menzies Institute for Medical Research|
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