DIASTOLIC HEART FAILURE

Definition: CHF w/ preserved systolic function (EF>40%) w/o other identifiable cause.

Etiologies: impaired relaxation and/or impaired distensibility of LV

1. LVH- HTN, HCMP, LV outflow obstruction (AS, IHSS)

2. Restrictive CMP

a. infiltrative- amyloid, sarcoid, hemochromatosis, transplant rejection

b. endocardial- fibroelastosis, fibrosis

c. DM

d. idiopathic

1. Aging- “presbycardia”

2. Obesity

3. Abbreviated LV filling- sustained tachycardia, AF

4. Idiopathic

Differential diagnosis for CHF w/ normal LV systolic fxn:

1. Incorrect dx: not CHF

2. Reversible systolic dysfunction: HTN-related pulmonary edema, ischemia, peripartum CMP, EtOH CMP, tachycardia CMP, selenium or carnitine deficiency, infection, drugs.

3. RHF: pulmHTN, pulm stenosis, TV disease, RV CMP, RV infarction, RA myxoma, intracardiac shunt.

4. LA HTN: mitral stenosis or regurgitation, LA myxoma, pulm venous obstruction, high-output heart failure (thyrotoxicosis, AVF, beri-beri).

5. Non-cardiogenic pulmonary edema: constrictive pericarditis, tamponade

Clinical features and diagnosis:

1. H & P- 4 most reliable signs of CHF: 1) pulsus alternans, 2) reduced proportional pulse pressure ([SBP-DBP]/SBP < 0.25), 3) abnormal BP response to Valsalva, 4) JVD. NONE can differentiate systolic from diastolic dysfunction.

2. EKG: not useful to distinguish systolic from diastolic dysfunction.

3. CXR: enlarged cardiac silhouette more common in systolic dysfunction.

4. ECHO

Treatment: reverse what is reversible.

Etiology	Treatment
CAD
acute ischemia	anti-ischemic agents, revascularization
post-infarction scar or aneurysm	ACEI, rx residual ischemia
HTN	lower BP
HCMP	negative inotropes (CCB, beta-blockers), dual chamber PM, myomectomy
Restrictive CMP	rx reversible factors (avoid dig and beta-blockers in amyloid)
Valvular disease	surgery +/- diuretics, afterload reduction

Ramachandran et al. Arch Int Med. 156: 146-157, 1996.