Diastolic Heart Failure

Question 1

HFpEF Clinical Definition

Answer 1

1. 􏰁 Presence of signs or symptoms of congestive heart failure
2. 􏰁 Presence of normal or mildly abnormal left ventricular systolic function

􏰁 3. Presence of abnormal left ventricular diastolic dysfunction (abnormal LV relaxation, filling or stiffness)

Question 2

HFpEF Pathophys. Def.

Answer 2

􏰁 Filling of the left ventricle to a normal end-diastolic volume can occur only at higher than normal cardiac filling pressures

Question 3

Demographics of DHF

Answer 3

􏰁 Female predominance 􏰁 
Older (65+)
􏰁 Diabetes
􏰁 HTN
􏰁 Atrial fibrillation 􏰁 
Obesity
􏰁 Sleep apnea
􏰁 Kidney disease

Question 4

Structural Changes with Aging

Answer 4

􏰁 Increased cardiomyocyte size

􏰁 Increased apoptosis

􏰁 Decreased myocyte number

􏰁 Altered growth factor regulation

􏰁 Focal collagen deposition

Question 5

Functional Changes with Aging

Answer 5

􏰁 Blunted BAR (Beta adrenergic receptor) responsiveness

􏰁 Impaired excitation/contraction
coupling

􏰁 Altered calcium handling proteins

􏰁 Increased vascular, systolic & diastolic stiffness

Question 6

HTN and HFpEF

Answer 6

􏰁 Stimulus for LV hypertrophy, disproportionate to capillary density

􏰁 Increased vascular, LV systolic stiffness

􏰁 Impaired relaxation

􏰁 Increased diastolic stiffness

Question 7

HFpEF Clinical Presentation

Answer 7

􏰁 Typical patient: Elderly female with hypertension, perhaps obese or with diabetes mellitus, who has a small, thick-walled ventricle.

􏰁 Exercise intolerance.

􏰁 Can be very subtle in elderly.
- Activity is reduced to avoid symptoms. - “Getting older”.

Question 8

Stages of Diastole: Early Rapid Filling

Answer 8

Complex interplay of factors:

• Myocardial relaxation
• LA pressure
• LV elastic recoil/LV suction
• LV stiffness
• Mitral orifice area
• Pericardial constraint
• Ventricular interaction

Question 9

Stages of Diastole: Diastasis

Answer 9

􏰁 LA and LV pressures almost equal 􏰁

Contributes less than 5% LV filling

􏰁 Duration shortens with tachycardia 􏰁

Onset contingent upon:

• effectiveness of LV relaxation
• LV compliance

Question 10

Stages of Diastole: Atrial Systole

Answer 10

􏰁 Contributes 15-25% LV diastolic filling in normal individuals

􏰁 Effectiveness contingent upon:

• PR interval
• atrial inotropic state
• atrial preload and afterload
• autonomic tone
• HR

Question 11

Potential Mechanisms of Diastolic Dysfunction

Answer 11

Normal diastolic function relies on:

• Calcium removal from the cytosol
• SR Ca2+ ATPase (reuptake)
• Phospholamban (inhibits SERCA)
• Facilitated by catecholamines
• Myosin dissociation from actin
• Compliant left ventricle
• Normal ventricular afterload

Question 12

Causes of HFpEF

Answer 12

1. Episodic LV systolic dysfunction w/improvement
2. Obstruction to LV inflow
3. Severe Valvular Dysfunction

• **4.Diastolic Dysfunction
• Impaired left ventricular relaxation
• Increased myocardial stiffness
• Ventricular interaction or pericardial restraint
• Abbreviated LV filling time

5. Multifactorial

Question 13

CV Stressors that Commonly produce HF sx in pts w/Diastolic Dysfunction

Answer 13

1. Exercise
2. HTN
3. Atrial Arrhythmias
4. Ischemia
5. Tachycardia