Heart Disease part 2

Sep 16, 2017

This is the second of a two part series on heart disease. The first article dealt with CAD(Coronary Artery Disease). This time the topic will be Congestive Heart Failure(CHF) and a basic explanation of the valves in the heart and how they can malfunction.
    CHF happens when the heart can no longer effectively pump blood. Some causes of this can be CAD or HBP(high blood pressure).This occurs because these conditions leave the heart too weak or too stiff to function properly.There are some things a person suffering from CHF can do to improve their quality of life. Decreasing salt intake, start a gradual exercise program(walking), managing stress, and losing weight if obese.Unfortunately, not all causes of CHF respond to treatment. More on this later. The best way to prevent CHF is to control things that cause it, such as CAD, HBP, diabetes, or obesity.
    CHF may be chronic, or have a very sudden, abrupt onset. Symptoms and signs may include some combination of these listed; shortness of breath(dyspnea) when you exert yourself or lie down, fatigue or weakness, swelling of legs, ankles, or feet, or irregular,rapid heart beat, reduced ability to exercise, persistent cough or wheezing with white or pinkish phlegm.
    If you have chronic CHF and some of the above symptoms get markedly worse seek immediate help.
    The heart can become stiff and fail without becoming weak. This is best demonstrated by heart failure caused by HBP. As the heart is asked to pump harder and harder against an increased resistance, at some point the muscle loses its ability to contract effectively and this results in failure.Heart failure can either be left-sided( left ventricular failure) or right-sided ( right ventricular failure). Usually both sides of the heart both fail.
Major causes include HBP, CAD,MI (heart attack), damaged heart valves, and damage to the muscle itself ( cardiomyopathy). Cardiomyopathy can be caused by some diseases, infections ( virus most common), alcohol abuse, and toxic drugs like cocaine or chemotherapy. In addition, there are congenital causes (defects you are born with), and conditions such as diabetes, HIV, elevated and depressed thyroid function,  an abnormal buildup of protein or iron, and sleep apnea.Smoking and obesity are contributing factors that cause diseases or conditions that can bring on heart failure.
    Complications that can occur with heart failure are related the cause and severity of the failure. Kidney damage and even failure can occur becauses as blood flow backs up in the kidneys, they lose the ability to function properly. Since the pressure within the heart itself rises, this puts a larger workload on the heart valves and can causes them to malfunction. Irregular heart rhythms can also happen with heart failure. The liver,as the kidneys, can be damaged by the backup of blood that causes increased pressure in the liver and scarring.
    Some people’s’ heart failure and symptoms can be improved with medication and lifestyle changes. Others , however, with severe and untreatable failure may a transplant or a left ventricular assist device.
    A brief overview of heart valves will follow. Think of these structures as little doors that open and close and allow blood to flow in one direction only. The most important valves in the heart are the Aortic Valve ( AV) and the mitral valve (MV). There are other valves in the heart ,but they are much less involved in malfunctions.
    There are two types of problems that affect the function of these valves. One is stenosis (narrowing), where blood flow is decreased. The other is regurgitation (backward blood flow) where more blood flows back into the right or left ventricles (lower chambers of the heart) and less flows out to the body. The fraction of blood being pumped out of the heart should be at least 50%. Multiple causes of valve problems are congenital ( born with) defects, infections, mechanical,and IV drug abuse. Valves can be surgically replaced, but can be risky in very sick patients. One great advance with aortic valve replacement is called TAVR. This stands for Transluminal Aortic Valve Replacement. This procedure can be done through an artery leading back to the aortic valve and removing and replacing it with a new one. It has allowed desperately ill patients a chance to lead very normal lives.
    
    I hope these last two monthly articles on heart disease have been helpful. I know the amount of material is huge, but i have tried to simplify as much as possible. If any of you have more questions, you can reach me at The Long Islander website.
                                
                        Keith M. Oshan, M.D.