Diastolic Dysfunction

Dr. S. Parthasarathy MD., DA., DNB, MD (Acu),

Dip. Diab.DCA, Dip. Software statistics PhD (physio)

Diastole

• 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 diseasesGlycogen storage disease

Hemochromatosis

Common precipitating factors

• 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

• Optimize circulating volume (hemodynamics).• ACE inhibitors• Aldosterone antagonists (theoretical benefit)• Salt and water restriction• Diuresis, • Improve survival.• Beta blockers• ACE inhibitors

SHF and DHF ??

• Diuretics ??• Digoxin ?? • Venodilators ?? • Beta blockers !!

summary

• Phases of diastoly • Dysfunction • Causes • Symptoms • Diagnosis• Treatment

Thank you all