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Diastolic heart failure • Up to a third of patients have clinical heart failure with normal LV systolic function • Underlying pathophysiology relates to diastolic dysfunction • Commonest underlying pathologies – Normal ageing – Hypertension – Myocardial ischaemia Mechanisms of diastolic dysfunction • Impaired ventricular relaxation – Energy dependent process – Susceptible to myocardial ischaemia • Decreased myocardial compliance – Altered compliance mediated by collagen – Fibrosis related to activation of RAAS Echocardiographic assessment • 2D echo to assess systolic function • Doppler echo – Transmitral flow • E/A wave ratio • E wave deceleration time – IVRT Area-length method for calculation of LV mass LVmass=1.05[5/6(A1xL1)-5/6(A2xL2)] Divide by body surface area to get LV mass index Reichek et al. Circulation 1983;67:348-52 Doppler patterns of diastolic dysfunction • Impaired relaxation – Reduced E/A ratio – Increased EDT – Increased IVRT • Restriction – – – – LA pressure increases due to myocardial stiffness High peak E wave velocity Short EDT Very short IVRT Treatment of diastolic heart failure • Treat underlying cause eg ischaemia • Impaired relaxation – Theoretically rate-limiting agents effective • • • • Beta-blockers, verapamil Reduce HR and prolong diastole Reduce myocardial oxygen demand Lower BP and reduce LVH Treatment of diastolic heart failure • Restriction – Drugs which reduce fibrosis and lower LA pressure theoretically should be effective • ACEI • AII blockers • Diuretics – If LA pressure lowered too much cardiac output significantly worsened • Can cause significant morbidity Colour Doppler Tissue Imaging Colour Doppler Tissue Imaging Figure 1. Pulsed wave Doppler sample of basal septum of normal subject S wave A wave E wave Figure 2. Pulsed wave Doppler sample of basal inferior wall of subject with previous inferior myocardial infarction due to right coronary artery occlusion. S wave E wave A wave