A Mental Enema on Heart Failure

     The diagnosis of heart failure is tough to achieve because there are no definitive lab or imagining results, thus the diagnosis is largely clinical. Some common symptoms are dyspnea and fatigue, with signs of volume overload (edema, rales, hepatojugular reflex,  etc.) There are two classes of heart failure. Systolic heart failure is more of the classical variety. The patient will have a low ejection fraction (<40%) cardiomegaly, and a dilated  (left) ventricle. The heart exam may reveal an S3 on auscultation. Commonly, on board exams, the patient will be a man with persistent atrial fibrillation and a previous MI. 

     In diastolic heart failure, the patient is a elderly woman with a history of HTN, diabetes, obesity, or paroxysmal atrial fibrillation. They wont have a history of CAD. The ejection fraction is normal, the left ventricle is not dilated, and the valves are fine. There will be elevated left atrial pressure, decreased left ventricle compliance, or impaired left ventricle relaxation on echo. The left ventricle will have thick walls, a small cavity and thick. There will be a prominent S4 on auscultation. 

     BNP is a popular test to order on a patient with dyspnea if you want to rule out HF. You want to get it below 95 pg per ml. If the patient has already been diagnosed with  HF , BNP can be used to predict mortality, at a level above 200 pg per ml. A 30-50% drop at hospital discharge is a good sign of improved survival and reduced readmission.

     A chest x ray may show congestion, edema, effusion or cardiomegaly and is used to evaluated pulmonary causes of HF.

     The framingham criteria is used to diagnosis HF. If the criteria are not met or if the BNP is normal (and you have clinical suspicion), the you can do an echo. If the criteria is met than you can do an echo as well. 

     The AHA classification can be used to guide treatment.  In class A, the patient is only at high risk , but no symptoms of structural problems. Here, your want to try and reduce the patients' risk factors. In class B, they are at high risk and there is some structural issues, but no symptoms. You can start the patient on an ACE or ARB, and a beta blocker. In class C, the patient is having symptoms in addition to A and B. You may want to add diuretics, digoxin, or consider revascularization, a pacemaker, or valve replacement. Digoxin is given to patients who have CHF with a low ejection fraction and atrial fibrillation with a rapid ventricular response.   In class D , the patient is in end stage HF, refractory to treatment. These patient are going to need inotropes, a transplant and/or hospice.