Heart Failure

Definition/Description

Heartfailure.jpg

Heart failure (HF) is a complex clinical syndrome that results from either functional or structural impairment of ventricles resulting in symptomatic left ventricle (LV) dysfunction.

  • The symptoms come from an inadequate cardiac output, failing to keep up with the metabolic demands of the body.
  • It is a leading cause of cardiovascular morbidity and mortality worldwide despite the advances in therapies and prevention.
  • It can result from disorders of the pericardium, myocardium, endocardium, heart valves, great vessels, or some metabolic abnormalities.[1]

The condition can be acute, transient, or chronic:

  • Acute is the first presentation of heart failure or a sudden onset of heart failure
  • Transient is when heart failure is recurrent or episodic
  • Chronic is heart failure that is persistent, worsening, or decompensate (to lose ability to function). It usually offset at first by compensatory mechanisms to maintain tissue perfusion, but eventually cardiac function declines and symptoms develop.[2]

Classification of HF

  • Heart failure can be classified as predominantly left ventricular, right ventricular or biventricular based on the location of the deficit.
  • HF is classified as acute or chronic, depending on the time of onset,
  • Clinically, it is typically classified into two major types based on the functional status of heart: heart failure with preserved ejection fraction (HFpEF) and heart failure with reduced ejection fraction (HFrEF)[3].
  • HF can classified into four functional classes.The New York Heart Association (NYHA) classification:
    1. HF does not cause limitations to physical activity; ordinary physical activity does not cause symptoms.
    2. HF causes slight limitations to physical activity; the patients are comfortable at rest, but ordinary physical activity results in HF symptoms.
    3. HF causes marked limitations of physical activity; the patients are comfortable at rest, but less than ordinary activity causes symptoms of HF.
    4. HF patients are unable to carry on any physical activity without HF symptoms or have symptoms when at rest[3].
Left ventricular hypertrophy.jpg

Left Ventricular Failure (LVF):

Image R: Gross pathology of concentric left ventricular hypertrophy. Left ventricle is at right in image, serially sectioned from apex to near base.

This is the most common form of heart failure, gradually pushing up the pressure in the left atrium and pulmonary vascular system. The resulting pulmonary hypertension may force fluid into the alveoli creating pulmonary oedema. This can cause compensatory mechanisms[4]:

  • Fast-acting neural systems increase sympathetic acting, raising heart rate and myocardial contractility
  • The slower response of the renin-angiotensin mechanism promotes the retention of sodium and water by the kidney, increasing preload and encouraging myocardium to contract
The compensatory mechanisms raise the workload of the left ventricle further because angiotensin is an arterial vasoconstrictor and increases the afterload. Other factors that can increase the workload of the left ventricle are increased volume load as in aortic valve regurgitation, or increased resistance to flow such as with systemic hypertension.[5]
Right side heart failure.jpg

Right Ventricle Failure (RVF):

This generally occurs secondary to cardiopulmonary disorders such as pulmonary hypertension, right ventricle infarction, congenital heart disease, pulmonary embolism or COPD. It is usually irreversible unless the ventricles are under-loaded e.g. by lung transplant for pulmonary hypertension. Enlargement of the right ventricle that has resulted from lung disease is referred to as cor pulmonale and is caused by hypoxic vasoconstriction and pulmonary hypertension.[4]

Image R: A depiction of heart enlargement during RVF, normal heart L, overstretched muscles heart R.

Biventricular heart failure

Heart failure most typically occurs on the left side of the heart. When the damage expands and also impacts the right side it is referred to as biventricular heart failure. Symptoms can be reflective of both left and right-sided heart failure, including shortness of breath and swelling due to a build-up of fluid[6]

Helpful Terminology:

  • Stroke volume: volume of blood ejected by the ventricle in one contraction, usually 70ml
  • End diastolic volume: volume of blood in the ventricle at the end of filling, just before it contracts, usually 120ml
  • Ejection fraction: stroke volume expressed as a percentage of end-diastolic volume, normally >55%
  • Systolic heart failure: reduced or weakened pumping action of the heart, with ejection fraction <55%
  • Diastolic heart failure: low compliance of myocardium, but with normal contraction and normal ejection fraction
  • Preload: degree of stretch applied to the ventricle before contraction
  • Afterload: the load that the ventricle must overcome to eject blood[4]
The 12 minute video below is on the classification of HF according to severity.
[7]

Epidemiology

  • HF is a significant public health problem with a prevalence of over 5.8 to 6.5 million in the U.S. and around 26 million worldwide.
  • The expectation is that 8 million people in the United States will have this condition by 2030, accounting for a 46% increase in prevalence.
  • The prevalence of HF increases with age as per data from Framingham Heart Study that estimated the prevalence of HF to be 8 per 1000 in men at age 50 to 59 years and goes up to 66 per 1000 in men at ages 80 to 89 years, similar values in women (8 and 79 per 1000).
  • At age 45 years, the lifetime risks for HF through age 75 or 95 years were 30% to 42% in white men, 20% to 29% in black men, 32% to 39% in white women, and 24% to 46% in black and higher BP and BMI at all ages led to higher lifetime risks.
  • The increase in HF prevalence does not necessarily have links with an increase in HF incidence. The aging of the population and modern therapies to cardiac patients that led to increase survival could explain the increase in prevalence even with a reduction in the incidence (due to prevention programs and better treatment of acute coronary syndromes).[1]
  • It is estimated that around 800,000 people in the UK suffer from heart failure, a number which will continue to rise due to an ageing population, improved survival rates following a heart attack, and more effective treatments.[5]
  • The British Heart Foundation reports that 0.9% of men and 0.7% of women in the UK suffer from heart failure, rising to 13.1% of men and 11.9% of women aged over 75 years old.[5]
  • Heart failure is the leading cause of hospitalisation in the elderly population and accounts for one million inpatient bed-days[2].
  • Survival rates for heart failure patients are variable, dependent on the age and severity of disease of the patient, and the quality of care they receive[2].
  • Outcomes are consistently poor for patients who receive suboptimal care, but input from heart failure specialists and prescription of evidence-based heart failure therapies have a significant impact on prognosis and life expectancy[5].
  • The National Heart Failure Audit has reported around one in ten patients dying in hospital, and of those who survive between one-quarter and one-third dying within the year of their admission[5]. However, these mortality rates are beginning to reduce, reflecting more consistent implementation of guidelines for recommended practice.[5]

Aetiology

  • Coronary Artery Disease.png
    Multiple conditions can cause HF, including systemic diseases, a wide range of cardiac conditions, and some hereditary defects.
  • Etiologies of HF vary between high-income and developing countries, and patients may have mixed etiologies.
  • Coronary Artery Diseasea(CAD)nd chronic obstructive pulmonary disease (COPD) are the most common underlying causes of HF in high-income regions. Conversely, hypertensive heart disease, rheumatic heart disease, cardiomyopathy, and myocarditis are the primary conditions for HF in low-income regions according to a systemic analysis for the Global Burden of Disease Study.
  • More than two-thirds of all cases of HF are attributable to CAD, COPD, hypertensive heart disease, and rheumatic heart disease[1].
  • A number of health conditions increase your chances of developing heart failure but in general, it is caused by an excess workload placed on the heart[4].

Other potential causes of heart failure[2]include

Pathophysiology

The pathophysiology of HF is complex and includes structural, neurohumoral, cellular, and molecular mechanisms activation to maintain physiologic functioning (maladaptation, myocyte hypertrophy, myocyte death/apoptosis/regeneration, and remodeling).[1]

  • In response to increased load, the left ventricular myocardium hypertrophies.
  • The greater size and number of myocytes raise myocardial oxygen demand and increases diffusion distance for oxygen.
  • Some muscle fibres become ischaemic, leading to patchy fibrosis, stiffness and reduced contractability[2].
  • The workload may cause the ventricle to stretch and dilate, leading to further force being required to maintain cardiac output[2].
  • Systolic failure is by reduced ejection fraction and diastolic failure is by reduced end-diastolic volume.
  • Metabolic effects include loss of bone mineralisation, skeletal muscle and fat[4].
  • The stiffness and reduced contractibility push up end-diastolic pressure, which is transmitted back along the pulmonary veins to the pulmonary capillaries, which causes fluid to be forced into the interstitial spaces and, if severe, into the alveoli, causing pulmonary oedema.
  • The increased pulmonary vascular pressure raises the afterload of the right ventricle, in the same way as chronic systemic hypertension raises the afterload of the left ventricle[5].
  • Hypertrophy, patchy fibrosis, stiffness and reduced contractibility of the right ventricular myocardium then ensues, as with left ventricle, and congestive cardiac failure develops[2].

Clinical Manifestations

Hf.png
Symptoms of heart failure include
  1. Those due to excess fluid accumulation (dyspnea, orthopnea, edema, pain from hepatic congestion, and abdominal distention from ascites) and
  2. Those due to a reduction in cardiac output (fatigue, weakness) that is most pronounced with physical exertion.
  • Acute and subacute presentations (days to weeks) are characterized by shortness of breath at rest and/or with exertion, orthopnea, paroxysmal nocturnal dyspnea, and right upper quadrant discomfort due to acute hepatic congestion (right heart failure).
  • Palpitations, with or without lightheadedness can occur if patient develops atrial or ventricular tachyarrhythmias
  • Chronic presentations (months) differ in that fatigue, anorexia, abdominal distension, and peripheral edema may be more pronounced than dyspnea. The anorexia is secondary to several factors including a poor perfusion of the splanchnic circulation, bowel edema, and nausea induced by hepatic congestion.

Characteristic features:

  • Pulsus alternans phenomenon characterized by evenly spaced alternating strong and weak peripheral pulses.
  • Apical impulse: laterally displaced past the midclavicular line, usually indicative of left ventricular enlargement.
  • S3 gallop: a low-frequency, brief vibration occurring in early diastole at the end of the rapid diastolic filling period of the right or left ventricle. It is the most sensitive indicator of ventricular dysfunction.[8]

Management

  • Heart failure disease management is a complex condition that requires a multidisciplinary framework for the care of patients, including discharge planning, patient education, and frequent outpatient assessment.
  • Emphasizing diet and medical compliance to patients with HF is important as one of the most common causes of HF readmission is the failure to comply either with diet or medications. A single session intervention could be beneficial as a randomized control trial of 605 patients with HF found that the incidence of all-cause hospitalization or mortality was not significantly reduced in patients receiving multisession self-care training compared to those receiving a single-session intervention.[1]
  • Cardiology, medical/surgical, and critical care nurses administer treatment, provide education, monitor patients, and communicate with the rest of the team so that everyone on the healthcare team operates from the same data set. The managing clinician would do well to consult with a board-certified cardiology pharmacist when initiating pharmaceutical care in HF cases[1].

Physiotherapy

Exercise older person.jpg

Physiotherapy is important in the management of heart failure. The cornerstone of physiotherapy management is cardiac rehabilitation. In patients undergoing heart surgery, physiotherapy can also help with recovery after surgery.

Up until the late 1980s, exercise was considered unsafe for the patient with HF. It was unclear whether any benefit could be gained from rehabilitation, and concern also existed regarding patient safety, with the belief that additional myocardial stress would cause further harm. Since this time, considerable research has been completed and the evidence resoundingly suggests that exercise for this patient group is not only safe but also provides substantial physiological and psychological benefits. As such, exercise is now considered an integral component of the non pharmacological management of these patients

Effective treatment for heart failure should aim to:

  • Strengthen the heart
  • Improve symptoms
  • Reduce the risk of a flare-up or worsening of symptoms
  • Improve Quality of Life
  • Offer longevity

Recent Research findings

  • Systematic review and meta-analysis show a significant effect of aerobic and resistance training on peak oxygen consumption, muscle strength, and health-related quality of life in patients with heart failure with a reduced left ventricular ejection fraction[9]
  • A study published in the Journal of Cardiopulmonary Rehabilitation and Prevention 2020, comparing the effects of β-blockers and non-β-blockers on Heart Rate (HR) and Oxygen Uptake (VO2) during exercise and recovery in older patients with heart failure with a preserved ejection fraction (HFpEF) demonstrated no significant differences in values (HRpeak, HRresv, HRrecov, or VO2) between both the groups, along with significant correlation between HRresv and VO2peak, suggesting the efficacy of these measures in prognostic and functional assessment and clinical applications, including the prescription of exercise, in elderly HFpEF patients[10].
  • Studies show a contrasting effect of aerobic training and resistance training on some echocardiographic parameters in patients with heart failure with reduced ejection fraction. While aerobic training was associated with evidence of worsening myocardial diastolic function, this was not apparent after resistance training. Further studies are indicated to investigate the long-term clinical significance of these adaptations[11].
  • А single-blind, prospective randomized controlled trial suggests: modified group-based High-intensity aerobic interval training (HIAIT) intervention showed more considerable improvement as compared to moderate-intensity continuous training (MICT) in the rehabilitation of patients with chronic heart failure (CHF). Physical and rehabilitation medicine (PRM) physicians should apply Group based Cardiac intervention in routine cardiac rehabilitation (CR) practice[12].
  • An article published online (March 2020) suggests positive outcomes with the High-intensity interval training (HIIT) for patients with heart failure along with preserved ejection fraction[13].
  • A study assessing patients carrying out 5-months cardiac rehabilitation CR showed a lower rate of clinical events with higher maximal inspiratory pressure, suggesting that the changes in respiratory muscle strength independently predicted the occurrence of clinical manifestations in patients with Heart Failure HF[14].

Multidisciplinary team members

The other members of the MDT are vast but include

  • Surgeons and consultants - They operate if needed. Numerous operations are available and may be suitable for certain patients. For example, Heart Valve Surgery, Angioplasty or Bypass, Left Ventricular Assist Devices, Heart Transplant. However, this is individual and would need to be discussed with the consultant in charge of the case.
  • Nutritionists - They work out a diet plan to suit the individual needs of the patient. As diet is a risk factor for CHD this is an extremely important member of the MDT for further prevention.
  • Counselor - As Heart failure is normally a lifelong condition the patient may have difficulty coming to terms with the impact this will have on their life. A counsellor will be available for sessions on coping with the disease.
  • Personal Trainer- As with a Physiotherapist will help to provide a more balanced lifestyle and improve fitness levels. This is something that will not only give the patient goals to work towards but also important social interaction with someone who is seen as less of a medical figure and therefore adds more normality to the individuals day to day life.
  • Family and Friends- This support network is an extremely important factor contributing to recover of a patient and should not be overlooked.

The list of people involved in this team is huge and is not exhaustive in this piece, however, Pharmacists, Social Groups, GP’s, Nurses and Podiatrists are all members of this MDT. Recovery cannot occur without input and communication from every member of the team.

Prevention

There are many factors that increase the risk of developing heart failure. And with some lifestyle changes and sometimes drug intervention this risk could be dramatically reduced. Hypertension and smoking are major risks for heart failure.

  • Stop smoking. Quitting smoking is noted as the single best way to reduce risk of heart failure. Smoking has many physiological effects forcing the heart to walk harder.
  • Reduce blood pressure. High blood pressure increases the work demand put on the heart to transport blood around the body, this increased work causes a hypertrophic reaction of the heart muscle, eventually leading to a weakened or stiff heart.
  • Reduce Cholesterol Level. High levels of cholesterol can cause furring and narrowing of the arteries termed atherosclerosis and eventually heart failure.
  • Lose weight. Being overweight increases demand placed on the heart and increases risk of heart failure and attack.
  • Eat a healthy diet. A healthy diet can help reduce your risk of developing coronary heart disease and therefore heart failure.
  • Keep active. Regular physical activity will help keep the heart healthy and also maintain a healthy weight.
  • Reduce Alcohol intake. Drinking excess of the recommended amount of alcohol per week can increase your blood pressure. Heavy drinking for long periods of time can cause damage to your heart muscle leading directly to heart failure.
  • Cut your salt intake. Excessive salt intake increases blood pressure and again, increases stress put on the heart.

Viewing

The below is a 12 minute video on HF

References

  1. 1.0 1.1 1.2 1.3 1.4 1.5 Hajouli S, Ludhwani D. Heart Failure And Ejection Fraction 2020.Available from:https://www.ncbi.nlm.nih.gov/books/NBK553115/ (last accessed 11.8.2020)
  2. 2.0 2.1 2.2 2.3 2.4 2.5 2.6 2.7 Dickstein, K.ESC Guidelines for the diagnosis and treatment of acute and chronic heart failure. European Journal of Heart Failure. 2008. Aug;10:933-989.
  3. 3.0 3.1 Inamdar AA, Inamdar AC. Heart failure: diagnosis, management and utilization. Journal of clinical medicine. 2016 Jul;5(7):62. Available from:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4961993/ (last accessed 12.8.2020)
  4. 4.0 4.1 4.2 4.3 4.4 Hough, A. Physiotherapy in Respiratory and Cardiac Care: An Evidence Based Approach. Hampshire. Cengage Learning EMEA; 2014.
  5. 5.0 5.1 5.2 5.3 5.4 5.5 5.6 British Society for Heart Failure. National Heart Failure Audit. London. November 2013.
  6. Health Union Heart Failure Available from: https://heart-failure.net/left-right-biventricular/ (last accessed 12.8.2020)
  7. classification system of heart failure
  8. Malik A, Brito D, Chhabra L. Congestive Heart Failure (CHF). InStatPearls [Internet] 2020 Jun 7. StatPearls Publishing.Available from:https://www.ncbi.nlm.nih.gov/books/NBK430873/ (last accessed 12.8.2020)
  9. Neto MG, Durães AR, Conceição LS, Roever L, Silva CM, Alves IG, Ellingsen Ø, Carvalho VO. Effect of combined aerobic and resistance training on peak oxygen consumption, muscle strength and health-related quality of life in patients with heart failure with reduced left ventricular ejection fraction: a systematic review and meta-analysis. International Journal of Cardiology. 2019 Jun 24.
  10. Maldonado-Martín S, Brubaker PH, Ozemek C, Jayo-Montoya JA, Becton JT, Kitzman DW. Impact of β-Blockers on Heart Rate and Oxygen Uptake During Exercise and Recovery in Older Patients With Heart Failure With Preserved Ejection Fraction. Journal of Cardiopulmonary Rehabilitation and Prevention. 2020 Jan 2.
  11. Lan NS, Lam K, Naylor LH, Green DJ, Minaee NS, Dias P, Maiorana AJ. The Impact of Distinct Exercise Training Modalities on Echocardiographic Measurements in Patients with Heart Failure with Reduced Ejection Fraction. Journal of the American Society of Echocardiography. 2019 Dec 4.
  12. MEDICA EM. Group-based cardiac rehabilitation interventions. A challenge for physical and rehabilitation medicine physicians: a randomized controlled trial. European Journal of Physical and Rehabilitation Medicine. 2020 Jan 23.
  13. Paul J Beckers, Andreas B Gevaert High intensity interval training for heart failure with preserved ejection fraction: High hopes for intense exercise European Journal of Preventive Cardiology 0(00) 1–3 The European S Article reuse guidelines: sagepub.com/journals-permissions DOI: 10.1177/2047487320910294 journals.sagepub.com/home/cpr
  14. Hamazaki N, Kamiya K, Yamamoto S, Nozaki K, Ichikawa T, Matsuzawa R, Tanaka S, Nakamura T, Yamashita M, Maekawa E, Meguro K. Changes in Respiratory Muscle Strength Following Cardiac Rehabilitation for Prognosis in Patients with Heart Failure. Journal of Clinical Medicine. 2020 Apr;9(4):952.