Patient with heart failure contemplates halting prescribed meds

A recent echocardiogram showed that he still has a severely dilated left ventricle with normal wall thickness and normal systolic function. He currently takes carvedilol, which raises his glucose and lowers his blood pressure, so he is tired and has no energy. He also takes 10 mg of lisinopril a day. He does not have high blood pressure. These were prescribed when he was diagnosed with congestive heart failure (CHF), prior to the AVM diagnosis.

With treatment, it seems his heart is functioning much better, as evident by his increased physical activity and stamina. My question is, despite the severely dilated left ventricle that hasn’t yet damaged the walls, does he still need to take the prescribed medications? If so, is there an alternative to carvedilol that does not raise glucose? — K.B.

ANSWER: There’s a lot going on, and although you have clearly learned a lot about your partner’s condition, some explanation is in order.

Heart failure is when the blood flow from the heart is inadequate for demand (called systolic failure), or when the pressure behind the heart is too high (diastolic failure), or both. A person can have heart failure with reduced ejection fraction (the proportion of blood squeezed out by the left ventricle every stroke, normally 50% to 75%) or heart failure with preserved ejection fraction. So, he has just moved from reduced to preserved.

Heart failure has many different etiologies. It’s not a diagnosis by itself; it’s more of a constellation of symptoms. One less-common cause is high-output heart failure, when the heart has done years of unnecessary work, causing it to fail. An AVM is a short circuit of the blood supply. Instead of oxygenated blood going from the artery to tissue capillaries (the tiny blood vessels where oxygen is delivered to cells), the blood goes directly into the vein and is returned to the heart without having done its duty. A very large AVM can take up a sizable proportion of blood flow.

The B-type natriuretic peptide (BNP) test is a blood test where levels increase in people with heart failure. The fact that his level went down with treatment of the AVM is evidence that his heart is less stressed.

Treatment of heart failure requires judgment. Some cardiologists make heart failure their whole area of expertise, and that is the expert who ideally would be managing your partner. The evidence is strong that beta blockers (like carvidolol) and ACE inhibitors (like lisinopril) improve symptoms and reduce mortality in most people suffering from heart failure with reduced ejection fraction, even if their blood pressure is normal. In people with heart failure and preserved ejection fraction, like he has now, the role of beta blockers is less clear. The effect of carvidolol with glucose is seldom significant enough to cause problems in people without diabetes.

Many cardiologists would treat a person like your partner with different treatments, such as a SGLT2 inhibitor and a mineralocorticoid receptor blocker (both relatively new classes of medicines), especially if it seems like the beta blockers are not being very helpful. Truly, only an expert who treats patients like him every day and knows a lot about his case is in the position to treat him optimally.