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Although apical and midventricular Takotsubo cardiomyopathies (TTCs) share common triggers and pathophysiological features, little is known about the potential differences in left ventricular (LV) mechanistic properties between these TTC phenotypes. We sought to investigate whether LV systolic and/or diastolic function, as assessed invasively by left heart catheterization (LHC), differ according to ballooning patterns in the acute phase of TTC. One hundred and fourteen TTC patients were retrospectively identified between January 2009 and December 2015 at the University Hospital of Strasbourg, France. A comprehensive list of LV quantitative parameters was derived from LHC analysis for each patient. We examined 2 groups of patients according to ballooning patterns in the acute phase of TTC: patients with apical ballooning ("Apical group"; n = 76) and those with midventricular ballooning ("Midventricular group"; n = 38). LV minimal diastolic pressure (8.72 ± 6.72 vs. 5.02 ± 6.08 mmHg; p = 0.004), LV end diastolic pressure (23.11 ± 8.32 vs. 18.84 ± 8.06 mmHg; p = 0.01), and LV diastolic stiffness (LV stiffness 1: 0.29 ± 0.23 vs. 18.84 ± 8.06 mmHg/mL; p = 0.04-LV stiffness 2: 0.16 ± 0.08 vs. 0.12 ± 0.05 mmHg/mL; p = 0.005) were significantly higher in patients with apical TTC than in the midventricular group. Concomitantly, these findings were associated with significantly higher BNP levels in the apical group (923.91 ± 1164.53 vs. 418.71 ± 557.75 pg/mL; p = 0.004) than in the midventricular group. In the acute phase of stress cardiomyopathy, the classic apical form of TTC is associated with poorer diastolic function compared to the midventricular ballooning variant, as assessed through direct invasive hemodynamic measurements using LHC.

Introduction/purpose: Hyperpnea and hyperinflation have been proposed as contributors to exaggerated energy demands in chronic obstructive pulmonary disease (COPD), yet there are incomplete data on exercise requirements. This study compared total-body energy demands of the internal (unloaded) and external work of cycling and delta mechanical efficiency in 40 patients (FEV1: 36+/-14% predicted) with COPD and 28 healthy age-matched controls while characterizing dynamic hyperinflation., Methods: Steady-state V O2 was obtained at rest, during unloaded and 20-W cycling, and at 20, 50, and 65% peak cycling power. Delta mechanical efficiency was calculated between constant-load cycling at 65 and 20% peak power. Dynamic hyperinflation was assessed from inspiratory capacity maneuvers., Results: Oxygen demands (L.min) at rest, for internal work (0.47+/-0.14 vs 0.45+/-0.11) or external work at 20 W (0.62+/-0.20 vs 0.57+/-0.13), were not different between patients and controls, although ventilation was elevated in COPD. Cycling at 65% of peak power induced dynamic hyperinflation in COPD, which indices were not related to cycling efficiency. Delta efficiency (%) was not different between patients (26.3+/-8.1) and controls (24.8+/-4.0)., Conclusion: Findings suggest that bioenergetics of submaximal cycling is not compromised in moderately severe COPD despite tachypnea and dynamic hyperinflation.