The contribution of a short electrocardiographic diastolic interval to diastolic dysfunction and HFpEF

Figures

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  Fig. 1. Central figure: study designs and outcomes: The contribution of a short electrocardiographic diastolic interval to diastolic dysfunction and HFpEF. Legend: We hypothesized that a shorter electrical diastole increases HFpEF risk, independent of heart rate. Study designs: The methods for assessing electrical diastolic interval in the patient and animal study are displayed in the center. R-R, TQ and TP intervals are extracted from body surface 12-lead ECG signals (green lines) in the patient study and from epicardial surface ECG signals (red lines = ECGI-TQ) in the animal study. For 12-lead ECG TQ interval was defined as the R-R interval minus QT interval, electrocardiographically representing the full diastole including early filling and atrial contract, while TP interval was defined as the R-R interval minus the sum of TQ interval and PQ interval, electrocardiographically representing solely early diastolic filling phase. For ECG imaging (ECGI) the epicardial repolarization to activation intervals were then taken as the difference between the recovery time of the preceding T-wave and activation time of the QRS, giving rise to an equivalent to the ECG TQ interval for each point on…

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  Fig. 2. Experimental set-up and results from animal study. Legend: A) total of 6 pigs were investigated. A) 256 electrodes were placed around the torso to record ECG signals. Echocardiography was performed simultaneously with electrical mapping through the square marked in black. B) TQ interval in relation to RR interval without and with sotalol administration. C) Correlation plot of TQ interval and E/A and lateral e’/a’ ratio at sotalol and pacing conditions. D) Mitral inflow velocity patterns from pulsed wave Doppler imaging. During right atrial (RA) pacing at 100 bpm there was a normal mitral inflow pattern and E was higher than A. With sotalol administration during concomitant 100 bpm pacing, E/A ratio inverted, reflecting an abnormal relaxation mitral inflow pattern

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  Fig. 3. Associations of TP and TQ interval with LVDD and HFpEF. Legend: Forrest plot displaying Odds Ratio (OR) and 95% confidence interval (CI) for the association of TQ and TP interval with LVDD and HFpEF in the population at increased cardiovascular risk as a whole, and stratified by sex. A total of 26,009 patients had prevalent LVDD and a total of 2,551 patients had prevalent HFpEF. None of the associations showed significant effect-modification by sex. Abbreviations: HFpEF, heart failure with preserved ejection fraction; LVDD, left ventricular diastolic dysfunction

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  Fig. 4. Regional myocardial differences in TQ interval. Legend: A) Anterior and inferior views of the ECG imaging (ECGI-TQ) TQ interval maps in one case study. TQ maps are shown during right atrial pacing at 100 bpm (top) and after perfusion of sotalol at 2 mg/kg (bottom). In each map, the left anterior descending artery is shown in black. An apparent gradient in TQ interval is observed with shorter TQ times at the basal regions (blue/green) compared to the apex (red). B) The change (Δ) in ECGI-TQ interval is largest at the inferolateral and anterolateral segments (pink) compared to the apex (yellow), based on the ECG imaging epicardial surface geometries. Abbreviations: Ant, anterior; Ant Lat, anterior lateral; Inf, inferior; Inf Lat, inferior lateral; RA, right atrial; RV, right ventricle