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Diastolic Dysfunction
Dr. S. Parthasarathy
MD., DA., DNB, MD (Acu),
Dip. Diab.DCA, Dip. Software statistics
PhD (physio)
Diastole
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Isovolumetric Relaxation Phase
Rapid Filling Phase
Diastasis
Atrial systoly
Diastoly
Cardiac cycle
• Isovolumetric
Relaxation Phase
• Rapid Filling Phase
• Diastasis
• Atrial systoly
Definition
• Diastolic Dysfunction refers to abnormalities
of active myocardial relaxation and passive
ventricular filling.
• Condition that includes classic CHF findings
and abnormal diastolic and normal systolic
function at rest
Why to know ??
• common discharge diagnosis for patients
older than 65 years.
• a patient cannot have pure systolic heart
failure
• 40 percent of patients with heart failure have
preserved systolic function.
• It can be attributed to one of the four
underlying mechanisms.
Four causes
• Slow/incomplete myocardial Relaxation:
the most common cause of this is myocardial
ischaemia, which causes the reduced rate of
LV pressure decline
Impaired peak LV filling rAte:
Pericardial constriction:
Altered elasticity:
What is the net effect??
The PV curve will be
Cellular level
• EC couple
• repolarization – relaxation coupling
• the calcium transient is prolonged as a result
of dysfunction of any of the processes
mentioned above.
• Lusitropy
Symptoms
• decreased exercise capacity;
• Neuro humoral activation with sodium and
water retention;
• paroxysmal nocturnal dyspnoea ; and
orthopnoea
Diastolic dysfunction
Storage diseases
Glycogen storage disease
Hemochromatosis
Common precipitating factors
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volume overload;
tachycardia; exercise; hypertension;
ischemia;
systemic stressors (e.g., anemia,
fever, infection, thyrotoxicosis);
arrhythmia
increased salt intake;
Use of NSAIDs.
Diagnosis – ECHO
•E
A
Under normal conditions, E is greater than A and the E/A
ratio is approximately 1.5.
Decrease initial to become one the back to 1.5
Transmitral flow velocity
Pulmonary venous flow (PVF):
• During atrial systole, there is normally a small
• amount of retrograde PVF.
• In DD, PVF reversal associated with atrial
contraction becomes progressively more
pronounced
Isovolumetric relaxation time
• IRT normal 70 ms
• DD it becomes 110 ms
• Deceleration time (DT): the rate of dissipation
of the transmitral pressure gradient is also a
function of LV compliance
• Normal 180 – 240 ms
• Abnormal > 240 → → 180 ms
Diagnosis
• Tissue Doppler:
• this uses Doppler shifts of ultrasound waves to
calculate the velocity of myocardial tissue
movement in a similar way to that of blood flow
• The serum brain natriuretic peptide (BNP) test
can accurately differentiate heart failure from
noncardiac conditions in dyspnea, but it cannot
distinguish diastolic from systolic heart failure
Treatment -Primary prevention
• smoking cessation
• aggressive control of hypertension,
• Hypercholesterolemia, coronary artery
disease.
• Lifestyle modifications such as weight loss,
dietary changes, limiting alcohol intake,
exercise are equally effective in preventing
diastolic and systolic heart failure
Treatment
• Regress left ventricular hypertrophy (decrease
wall thickness and remove excess collagen).
• Beta blockers, ACE inhibitors and ARBs
• Aldosterone antagonists
• Calcium channel blockers
• Maintain atrioventricular synchrony by managing
tachycardia
• Beta blockers (preferred)
• Calcium channel blockers (second-line agents)
• Digoxin (controversial)
Carvidolol
• both agents improve cardiac remodeling in
patients with congestive heart failure,
carvedilol provides superior resolution of left
ventricular fraction.
• Patients who do not respond to metoprolol
may improve when switched to carvedilol.
• carvedilol exhibits more favorable effects on
LV function than does nebivolol.
Treatment principles
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Optimize circulating volume (hemodynamics).
ACE inhibitors
Aldosterone antagonists (theoretical benefit)
Salt and water restriction
Diuresis,
Improve survival.
Beta blockers
ACE inhibitors
SHF and DHF ??
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Diuretics ??
Digoxin ??
Venodilators ??
Beta blockers !!
summary
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Phases of diastoly
Dysfunction
Causes
Symptoms
Diagnosis
Treatment
Thank you all