HEART failure is a clinical syndrome that results from problems with either the filling of the heart or pumping of blood from the chambers of the heart. This syndrome has many causes and worldwide has been increasing in prevalence.

In the United States of America, it is estimated that one out of every five people over the age of 40 will develop symptomatic heart failure in their lifetime. This risk increases with age. Over the past 40 years significant advances have been made in the diagnosis and management of patients with heart failure with the subsequent improvement in the outcome of some groups of patients. The fact remains, however, that heart failure is a syndrome associated with significant morbidity and unacceptably high mortality with an outcome that is worse than many cancers. An important aspect of the heart failure syndrome is that for most patients who are diagnosed with symptomatic heart failure, the disease is progressive with worsening symptoms, decreased quality of life and increasing risk of death over time. Heart failure can be clinically staged into four groups: stage A, B, C and D. Stage D represents the sickest patients who have the highest risk of death. The five-year survival for these patients is 20 per cent. This means that eight out of 10 people diagnosed with Stage D heart failure will die within five years of diagnosis. Stage C represents patients who have or previously had symptoms which have improved. The five-year survival in this group is 75 per cent. The groups with the earliest stages of disease, stage A and stage B, have the best outcome with five-year survivals of 98 per cent and 97 per cent, respectively.

For much of the past 40 years, diagnosis and treatment has been focused on patients with stage C and stage D disease as these are the patients who present to the medical system for care. More recently focus is being placed on patients at earlier stages in the hope of slowing or preventing the progression of early-stage patients to more advanced symptomatic disease. Patients with stage A and stage B disease do not have any clinical findings of heart failure but are at risk of developing symptomatic heart failure in the future. Patients with stage B heart failure (so called pre-heart failure) have changes in the heart structure or function but currently have no symptoms. Some examples of these patients include: patients with thickened heart muscle from hypertension, patients with narrowed or leaking heart valves and patients with narrowing in the arteries that supply blood to the heart. Over time as the disease progresses many of these patients will develop symptoms and worsening outcome.

Stage A: (At risk for heart failure)

The concept behind the classification of patients for heart failure can be difficult for the layperson to grasp. Stage A heart failure consists of patients who have diseases that put them at significantly increased risk of heart failure in the future. These patients currently have normal heart structure and function (otherwise they would be in stage B) and have no symptoms of heart disease. Some examples of these patients would include patients with hypertension, diabetes, obesity, those exposed to cardiotoxic agents, patients with genetic risk for cardiomyopathy or strong family history of cardiomyopathy. This pool of patients is quite large and is increasing over time. A study in Belgium found that in the age group of 45 years or older stage A heart failure was diagnosed in 27 per cent of the population in the year 2000 and 35 per cent of the population in the year 2015. Some may point out that in diagnosing these people with heart failure we are giving a disease to patients who have no current evidence of heart disease and who have an excellent five-year survival (98 per cent). However, the important thing to point out is that significant proportions of these people will develop heart failure over time with subsequent increasing risk of death and morbidity. The diagnosis of stage A heart failure allows recognition of this risk and the implementation of measures to try to reduce the risk of progression to symptomatic heart failure. An important aspect of this is ongoing research to demonstrate what measures can improve outcome in these patients. For some diseases the data is quite clear while other remain areas of active research.

Hypertension and coronary artery disease (CAD)

Hypertension and CAD are the largest contributor to the risk of heart failure on a population basis. Elevation in both the systolic and diastolic blood pressures are associated with future risk of heart failure. This risk is related to duration of the hypertension and how well the hypertension is controlled. A diagnosis of hypertension increases the risk of heart failure in women by a factor of three and men by a factor of two. The most important point to note is the adequate treatment of hypertension can reduce the risk of heart failure by 50 per cent. Additionally, it should be noted that 35.8 per cent of Jamaican women and 31.7 per cent of Jamaican men are hypertensive and these numbers have been increasing over time. This indicates a significant likelihood of heart failure in the future as a public health concern in Jamaica.

Narrowed arteries from CAD block blood flow to heart muscle. Over time, CAD can weaken the heart muscle. This may lead to heart failure. Past heart attack (myocardial infarction) also a consequence of CAD results in denial of oxygen and nutrients to the heart muscle and results in damages to the heart’s muscle tissue — part of it essentially “dies”. The damaged heart tissue does not contract as well, which weakens the heart’s ability to pump blood. Over time, this leads to heart failure. It is estimated that about 7,500 heart attacks occur each year in Jamaica. Many of these patients have limited access to optimal health care and so do not survive. Unfortunately, also, many of the heart attack survivors are not adequately or appropriately treated and so at high risk for heart failure over time. These cases will further burden the already burdened health-care system. Treating heart attack and CAD appropriately will significantly decrease the risk of future heart failure and limit strain on the economy and health-care system in the future.

Next week we will look at diabetes, obesity and other conditions for stage A heart failure.

Dr Ernest Madu, MD, FACC and Dr Paul Edwards, MD, FACC are consultant cardiologists for Heart Institute of the Caribbean (HIC) and HIC Heart Hospital. HIC is the regional centre of excellence for cardiovascular care in the English-speaking Caribbean and has pioneered a transformation in the way cardiovascular care is delivered in the region. HIC Heart Hospital is registered by the Ministry of Health and Wellness and is the only heart hospital in Jamaica. Correspondence to info@caribbeanheart.com or call 876-906-2107