Download Diastolic heart failure

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
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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
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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