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Background: Echocardiography (echo)-based linear fractional shortening (FS) is widely used to assess left ventricular dysfunction (LV dys ), but has not been systematically tested for right ventricular dysfunction (RV dys )., Methods: The population comprised LV dys patients with and without RV dys (EF<50%) on cardiac MRI (CMR): Echo included standard RV indices (fractional area change [FAC], TAPSE, S', and FS in parasternal long-axis (RV outflow tract [RV OT ]) and apical four-chamber views (width [RV WD ], length [RV LG ])., Results: A total of 168 patients underwent echo and CMR (3±3 days); FAC (46±9 vs 28±11), TAPSE (1.9±0.4 vs 1.5±0.3), and S' (11.4±2.3 vs 10.0±2.6, all P≤.001) were lower among RV dys patients, as were FS indices (RV OT 32±8 vs 17±10 | RV WD 40±11 vs 22±12 | RV LG 16±5 vs 9±4%; all P<.001). FS indices yielded similar magnitude of correlation with CMR RVEF (r=.73-.56) as did FAC (r=.70), which was slightly higher than TAPSE (r=.47) and S' (r=.31; all P<.001). FS indices decreased stepwise vs CMR RVEF tertiles, as did FAC (all P<.001). In multivariate analysis, FS in RV OT (regression coefficient .51 [CI 0.37-0.65]), RV WD (0.30 [0.19-0.41]), and RV LG (0.45 [0.20-0.71]; all P≤.001) was independently associated with CMR RVEF. FS indices yielded good overall diagnostic performance (AUC: RV OT 0.89 [CI 0.82-0.97] | RV WD 0.87 [0.78-0.96] | RV LG 0.80 [0.70-0.90]; all P<.001) for CMR-defined RV dy (RVEF<50%)., Conclusions: RV linear FS provides RV functional indices that parallel CMR RVEF. Parasternal long-axis RV OT width, four-chamber RV width, and length are independently associated with RVEF, supporting use of multiple FS indices for RV functional assessment., (© 2017, Wiley Periodicals, Inc.)

Background: Right ventricular (RV) and left ventricular (LV) function are closely linked due to a variety of factors, including common coronary blood supply. Altered LV perfusion holds the potential to affect the RV, but links between LV ischemia and RV performance, and independent impact of RV dysfunction on effort tolerance, are unknown., Methods and Results: The population comprised 2051 patients who underwent exercise stress myocardial perfusion imaging and echo (5.5±7.9 days), among whom 6% had echo-evidenced RV dysfunction. Global summed stress scores were ≈3-fold higher among patients with RV dysfunction, attributable to increments in inducible and fixed LV perfusion defects (all P≤0.001). Regional inferior and lateral wall ischemia was greater among patients with RV dysfunction (both P<0.01), without difference in corresponding anterior defects (P=0.13). In multivariable analysis, inducible inferior and lateral wall perfusion defects increased the likelihood of RV dysfunction (both P<0.05) independent of LV function, fixed perfusion defects, and pulmonary artery pressure. Patients with RV dysfunction demonstrated lesser effort tolerance whether measured by exercise duration (6.7±2.8 versus 7.9±2.9 minutes; P<0.001) or peak treadmill stage (2.6±0.9 versus 3.1±1.0; P<0.001), paralleling results among patients with LV dysfunction (7.0±2.9 versus 8.0±2.9; P<0.001|2.7±1.0 versus 3.1±1.0; P<0.001 respectively). Exercise time decreased stepwise in relation to both RV and LV dysfunction (P<0.001) and was associated with each parameter independent of age or medication regimen., Conclusions: Among patients with known or suspected coronary artery disease, regional LV ischemia involving the inferior and lateral walls confers increased likelihood of RV dysfunction. RV dysfunction impairs exercise tolerance independent of LV dysfunction., (© 2016 American Heart Association, Inc.)

Background: Echocardiography-derived linear dimensions offer straightforward indices of right ventricular (RV) structure but have not been systematically compared with RV volumes on cardiac magnetic resonance (CMR)., Methods: Echocardiography and CMR were interpreted among patients with coronary artery disease imaged via prospective (90%) and retrospective (10%) registries. For echocardiography, American Society of Echocardiography-recommended RV dimensions were measured in apical four-chamber (basal RV width, mid RV width, and RV length), parasternal long-axis (proximal RV outflow tract [RVOT]), and short-axis (distal RVOT) views. For CMR, RV end-diastolic volume and RV end-systolic volume were quantified using border planimetry., Results: Two hundred seventy-two patients underwent echocardiography and CMR within a narrow interval (0.4 ± 1.0 days); complete acquisition of all American Society of Echocardiography-recommended dimensions was feasible in 98%. All echocardiographic dimensions differed between patients with and those without RV dilation on CMR (P < .05). Basal RV width (r = 0.70), proximal RVOT width (r = 0.68), and RV length (r = 0.61) yielded the highest correlations with RV end-diastolic volume on CMR; end-systolic dimensions yielded similar correlations (r = 0.68, r = 0.66, and r = 0.65, respectively). In multivariate regression, basal RV width (regression coefficient = 1.96 per mm; 95% CI, 1.22-2.70; P < .001), RV length (regression coefficient = 0.97; 95% CI, 0.56-1.37; P < .001), and proximal RVOT width (regression coefficient = 2.62; 95% CI, 1.79-3.44; P < .001) were independently associated with CMR RV end-diastolic volume (r = 0.80). RV end-systolic volume was similarly associated with echocardiographic dimensions (basal RV width: 1.59 per mm [95% CI, 1.06-2.13], P < .001; RV length: 1.00 [95% CI, 0.66-1.34], P < .001; proximal RVOT width: 1.80 [95% CI, 1.22-2.39], P < .001) (r = 0.79)., Conclusions: RV linear dimensions provide readily obtainable markers of RV chamber size. Proximal RVOT and basal width are independently associated with CMR volumes, supporting the use of multiple linear dimensions when assessing RV size on echocardiography., Competing Interests: Conflicts of Interests Disclosure: None, (Copyright © 2016 American Society of Echocardiography. Published by Elsevier Inc. All rights reserved.)