heart failure 2 Flashcards
diastolic failure
- ↑ stiffness requires ↑ pressure to achieve the same LV filling volume
- difficulty/impaired filling
- ↓lusitropy / decrease in relaxation
- Produces ↓ SV
hallmark of diastolic dysfunction is
- normal ejection fraction
2. ventricular wall thickening
Primary causes of diastolic HF
- high afterload/pressure overload
- myocardial thickening/fibrosis
- external compression
High afterload / pressure overload caused by?
- Hypertension (long-standing)
- Aortic stenosis
- Dialysis (inadequate volume removal)
Myocardial thickening / fibrosis can be caused by
- Hypertrophic cardiomyopathy
2. Primary restrictive cardiomopathy
External compression
- Pericardial fibrosis / constrictive pericarditis
2. Pericardial effusion
Primary causes of right-sided HF
- Left heart failure
- Lung disease / pulmonary HTN / RV pressure overload
- RV Volume overload
- Damage to the RV myocardium
Left heart failure can be caused by?
Backward HF from LV dysfunction stresses the right side by increasing pulmonary venous pressures
Lung disease / pulmonary HTN / RV pressure overload can be caused by?
- Called “cor pulmonale” when primary lung dz causes HF
2. COPD, primary pulmonary hypertension, sleep apnea
RV Volume overload can be cause by?
- Shunt (interatrial septal defect)
2. Tricuspid regurgitation
Damage to the RV myocardium
can be caused by?
- Isolated RV infarct
2. Myocarditis
Clinically HF forms coexist
- Systolic dysfunction is typically accompanied by diastolic dysfunction and vice versa
a. Fibrosis (scar tissue can’t contract or relax)
b. Ischemia (relaxation is energy dependent) - LV failure often causes RV failure
The cycle of HF: the problem
decreased CO
The cycle of HF: the solution?
- Compensatory responses
- Neurohormal activation
- Frank-Starling (increasing preload)
- Ventricular hypertrophy and dilation
heart failure can be compensated for by?
frank starling by the SV being preserved by increased end diastolic filling/pressure