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Articles by R. B Weiner
Total Records ( 2 ) for R. B Weiner
  R. B Weiner , A. E Weyman , A. M Khan , J. S Reingold , A. A Chen Tournoux , M Scherrer Crosbie , M. H Picard , T. J Wang and A. L. Baggish
  Background—

Left ventricular (LV) rotation results from contraction of obliquely oriented myocardial fibers. The net difference between systolic apical counterclockwise rotation and basal clockwise rotation is left ventricular torsion (LVT). Although LVT is altered in various cardiac diseases, determinants of LVT are incompletely understood.

Methods and Results—

LV end-diastolic volume, LV apical and basal rotation, peak systolic LVT, and peak early diastolic untwisting rate were measured by speckle-tracking echocardiography in healthy subjects (n=8) before and after infusion of a weight-based normal saline bolus (2.1±0.3 L). Saline infusion led to a significant increase in end-diastolic LV internal diameter (45.9±3.7 versus 47.6±4.2 mm; P=0.002) and LV end-diastolic volume (90.0±21.6 versus 98.3±19.6 mL; P=0.01). Stroke volume (51.3±10.9 versus 63.0±15.5 mL; P=0.003) and cardiac output (3.4±0.8 versus 4.4±1.5 L/min; P=0.007) increased, whereas there was no change in heart rate and blood pressure. There was a significant increase in the magnitude of peak systolic apical rotation (7.5±2.4° versus 10.5±2.8°; P<0.001) but no change in basal rotation (–4.1±2.3° versus –4.8±3.1°; P=0.44). Accordingly, peak systolic LVT increased by 33% after saline infusion (11.2±1.3° versus 14.9±1.7°; P<0.001). This saline-induced increase in LVT was associated with a marked increase in peak early diastolic untwisting rate (72.3±21.4 versus 136.8±30.0 degrees/s; P<0.001).

Conclusions—

Peak systolic LVT and peak early diastolic untwisting rate are preload-dependent. Changes in LV preload should be considered when interpreting results of future LVT studies.

  A. L Baggish , R. B Weiner , G Kanayama , J. I Hudson , M. H Picard , A. M Hutter and H. G. Pope
  Background—

Although illicit anabolic-androgenic steroid (AAS) use is widespread, the cardiac effects of long-term AAS use remain inadequately characterized. We compared cardiac parameters in weightlifters reporting long-term AAS use to those in otherwise similar weightlifters without prior AAS exposure.

Methods and Results—

We performed 2D tissue-Doppler and speckle-tracking echocardiography to assess left ventricular (LV) ejection fraction, LV systolic strain, and conventional indices of diastolic function in long-term AAS users (n=12) and otherwise similar AAS nonusers (n=7). AAS users (median [quartile 1, quartile 3] cumulative lifetime AAS exposure, 468 [169, 520] weeks) closely resembled nonusers in age, prior duration of weightlifting, and current intensity of weight training. LV structural parameters were similar between the two groups; however, AAS users had significantly lower LV ejection fraction (50.6% [48.4, 53.6] versus 59.1% [58.0%, 61.7%]; P=0.003 by two-tailed Wilcoxon rank sum test), longitudinal strain (16.9% [14.0%, 19.0%] versus 21.0% [20.2%, 22.9%]; P=0.004), and radial strain (38.3% [28.5%, 43.7%] versus 50.1% [44.3%, 61.8%]; P=0.02). Ten of the 12 AAS users showed LV ejection fractions below the accepted limit of normal (≥55%). AAS users also demonstrated decreased diastolic function compared to nonusers as evidenced by a markedly lower early peak tissue velocity (7.4 [6.8, 7.9] cm/s versus 9.9 [8.3, 10.5] cm/s; P=0.005) and early-to-late diastolic filling ratio (0.93 [0.88, 1.39] versus 1.80 [1.48, 2.00]; P=0.003).

Conclusions—

Cardiac dysfunction in long-term AAS users appears to be more severe than previously reported and may be sufficient to increase the risk of heart failure.

 
 
 
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