Regional mechanical dyssynchrony and shortened systole are present in people with Takotsubo syndrome

Figures

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  Fig. 1. Pressure–volume and volume–time characteristics in control and Takotsubo patients. a Typical segmental 1 (apex) to 5 (base) pressure-volume (PV) loops and the global PV loop of a control (blue) and a Takotsubo (TTS) patient (red). The Y-axis represents pressure in mmHg, and the X-axis volume in ml. b Typical segmental 1 (apex) to 5 (base) volume-time diagrams and global volume-time diagram for a control (blue) and a Takotsubo (TTS) patient (red). The Y-axis measures volume in ml, and the X-axis time in ms. In each segment, the time from maximal (Vmax = start point) to minimal volume (Vmin) is indicated by black and red dotted lines, respectively. The global volume–time diagram also includes the pressure-time signal in green. The gray shaded area within the global volume-time signal illustrates the spread of time up to Vmin across all 5 segments, which is markedly more pronounced in the Takotsubo patient compared to the control, indicative of dyssynchrony. The percentage values in the individual volume-time diagrams reflect the dyssynchrony of the respective segment when it is out of phase with the global segment. Notably, these values are increased in the apical region in TTS.

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  Fig. 2. Assessment of dyssynchrony metrics in Takotsubo Syndrome and control patients. Patients with Takotsubo syndrome (TTS, n = 22) are depicted in red and controls (Co, n = 14) are shown in blue. a illustrates the Internal Flow Fraction (IFF), and (b) shows the Internal Flow (IF). c Depicts segmental dyssynchrony %, while (d) demonstrates the time to minimal segmental volume (Vmin). e Standard deviation (SD) of Vmin across all five segments for both TTS patients and controls. Exact p-values are presented, and statistical significance is assumed when p < 0.05, compared to controls. The inset p-values represent one-way ANOVA analysis for intersegmental variations. Data are presented as mean ± standard error of the mean (SEM). The inset diagram provides a schematic of the conductance catheter’s positioning within the left ventricle (LV), delineating the segments from apex (segment 1) to base (segment 5).

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  Fig. 3. Comparative traces between a control subject (blue) and a Takotsubo syndrome patient (red). a Representative volume-time traces, illustrating the heart’s volume changes over time. b Pressure–time traces, indicating the intraventricular pressure throughout the cardiac cycle. c dp/dt traces, which reflect the rate of pressure change within the ventricle, a key indicator of cardiac contractility. d Elastance–time traces, demonstrating the heart’s ability to contract and relax, while (e) presents the electrocardiogram traces, showing the electrical activity of the heart. Although the second heartbeat for both subjects starts simultaneously, as evidenced by the dashed line marking t = 0, the time dp/dtmax to dp/dtmin (depicted with dashed vertical red lines) is shorter in the Takotsubo patient. In addition, decreased end-systolic elastance (Ees, depicted with dashed vertical red lines) and a shortened time to reach end-systolic elastance (dTes, depicted with horizontal dotted black lines) are observed despite a lower heart rate. The shorter systolic period in the Takotsubo patient may be obscured by the slower heart rate; however, when corrected for heart rate (dTesc), the systolic…

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  Fig. 4. Systolic function parameters in Takotsubo Syndrome and control patients. Patients with Takotsubo syndrome (TTS, n = 22) are depicted in red and controls (Co, n = 14) are shown in blue. a Duration of systole (dTes), reflecting the duration of blood ejection from the left ventricle. b Systolic ejection time corrected for heart rate (dTesc), offering a heart rate-independent comparison. c Maximal increase of the elastance–time curves (dE/dtmax), a measure of the maximum rate at which the ventricle’s stiffness increases during systole. d Minimal decrease of the elastance-time curves (dE/dtmin), indicating the rate at which the ventricle’s stiffness decreases during relaxation. Exact p-values are presented, and statistical significance is assumed when p < 0.05, compared to controls, suggesting notable variations in the systolic function between the two groups. Data are presented as mean ± standard error of the mean (SEM).

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  Fig. 5. Segmental post-systolic contraction durations in Takotsubo Syndrome and controls. This graph illustrates the duration of post-systolic volume decrease across different segments of the heart from base to apex. It compares the time difference between the minimal segmental volume (TVmin) and the duration of systole (dTes) in patients with Takotsubo syndrome (TTS, n = 22; red) and control subjects (Co, n = 14; blue). Exact p-values are presented, and statistical significance is assumed when p < 0.05, compared to controls, obtained through one-way ANOVA for intersegmental comparisons within each group. Data are presented as mean ± standard error of the mean (SEM).