left heart failure and right heart failure because of

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Left heart failure and right heart failure because of pulmonary disease Dr. Szathmári Miklós Semmelweis University First Department of Medicine 28. Oct. 2013.

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Page 1: Left heart failure and right heart failure because of

Left heart failure and right

heart failure because of

pulmonary disease

Dr. Szathmári Miklós

Semmelweis University

First Department of Medicine

28. Oct. 2013.

Page 2: Left heart failure and right heart failure because of

Heart failure (HF)- definition

• HF is a clinical syndrome that occurs in patients who -because of an inherited or acquired abnormality of heart structure and/or function - develop a constellation of clinical symptoms (dyspnoea and fatigue) and signs (oedema and rales) that lead a poor quality of life, and a shortened life expectancy.

• Diagnostic criteria's:– Clinical symptoms of HF at rest or by exertion

– Identification of abnormal heart function in rest by objective imaging tools

– Improvement of the symptoms of HF by adequate therapy

• HF patients are categorized into one of two groups:– HF with a depressed ejection fraction (<40%)- systolic failure

– HF with a preserved ejection fraction (≥40%) – diastolic failure

Page 3: Left heart failure and right heart failure because of

Control of cardiac performance

and output• The stroke volume of the ventricle in the intact

heart depend on three major influences:– The length of the muscle at the onset of contraction

(the preload, surrogate parameter is the enddiastolic volume of the ventricle,EDV). Within limits the stroke volume relates closely the enddiastolic volume.

– The tension that the muscle is called upon to develop during contraction (afterload), the load that opposes shortening, or the tension developed in the ventricular wall during ejection.

– The contractility of the muscle (the extent and velocity of shortening at any given preload and afterload).

Page 4: Left heart failure and right heart failure because of

Determinants of stroke volume

• Ventricular preload– Blood volume

– Distribution of blood volume (body position, intrathoracic pressure, venous tone, etc.)

– Atrial contraction

• Ventricular afterload– Systemic vascular resistance

– Arterial blood pressure

– Elasticity of arterial tree

– Ventricular wall tension• Radius, wall thickness

• Myocardial contractility– Intramyocardial Ca+

– Cardiac adrenergic nerve activity

– Circulating catecholamine

– Cardiac rate

– Myocardial ischemia

– Myocardial cell death

– Myocardial fibrosis

– Alteration of sarcomeric and cytoskeletal proteins

– Ventricular remodelling

– Chronic overexpression of neurohormones

– Chronic myocardial hypertrophy

Page 5: Left heart failure and right heart failure because of

Functional classification of heart

failure (NYHA)

• NYHA functional classification:

– Class I. Without limitation of physical activity. No symptoms with ordinary exertion (latent decompensation)

– Class II. Slight limitation of physical activity. Ordinary activity causes symptoms, fatigue, palpitation, dyspnoea, anginal pain. (subdecompensation)

– Class III. Marked limitation of physical activity. Less than ordinary activity causes symptoms.

– Class IV. Inability to carry out any physical activity without discomfort. Symptoms are present at rest.

Page 6: Left heart failure and right heart failure because of

Epidemiology of heart failure

• The overall prevalence of HF in the adult population in developed countries is 2%.Over the age 65 affects 6-10% of people.

• The overall prevalence of HF is thought to be increasing (most common cause of hospital admissions), in part because current therapies of cardiac disorders, such as myocardial infarction, valvular heart disease, and arrhythmias, are allowing the patients to survive longer.

• Heart failure is the most common cause of death (In the USA 300 000 death/year)

• Patients with symptoms at rest have a 30-70% annual mortality rate. Patients with symptoms with moderate activity have an annual mortality rate of 5-10%

Page 7: Left heart failure and right heart failure because of

Pathogenesis of heart failure with

depressed ejection fraction

– HF begins after an index event (acute MI, or gradual onset as in the case of pressure or volume overload) produces an initial decline in pumping activity (systolic dysfunction). The compensatory mechanisms are activated, including:

• The adrenergic nervous system– to increase the myocardial contractility

• The renin-angiotensin-aldosterone system– for maintaining cardiac output through increased retention of salt and

water

• The activation a molecules (BNP, NO, PGE2, PGI2) and cytokin system that offset the peripheral vasoconstriction

– In the short term these systems are able to restore cardiovascular function with the result that the patient remain asymptomatic.

– However, with time the sustained activation of these systems can lead to secondary end-organ damage within the ventricle, with left ventricular remodelling and subsequent cardiac decompensation.

Page 8: Left heart failure and right heart failure because of

Pathogenesis of heart failure

Increased

sympathetic

activity

Stimulation of cardioregulatory

centre

Increased

AVP secretion

Stimulation

of RAAS

Index event, that

decreases cardiac

output

The functional

capacity is preserved

or is depressed only

minimally Genetic background,

age, gender,

environment

Activation of

vasodilatators

(BNP,NO, PGs,

TNF-α

Symptomatic heart

failure by activation of

left ventricle

remodelling (mass,

shape, volume,

composition

Influence on heart rate, preload, contractility and afterload

Page 9: Left heart failure and right heart failure because of

Pathogenesis of heart failure

with preserved ejection fraction

• Diastolic dysfunction– Impaired myocardial relaxation, an ATP-dependent

process that is regulated by uptake of cytoplasmatic Ca2+ into the sarcoplasmatic reticulum

• Reduction in ATP concentration in case of ischemia

• Decreased left ventricle compliance (from hypertrophy or fibrosis)

• An increase in heart rate disproportionately shortens the time of diastolic filling, which may lead to elevated left ventricle filling pressures. Elevated LV end-diastolic filling pressures results in increases in pulmonary capillary pressures, which can contribute to the dyspnoea

– Increased vascular and ventricular stiffness may be also important

Page 10: Left heart failure and right heart failure because of

Left ventricular remodelling

The transition to symptomatic HF is accompanied by increasing activation of neurohormonal, adrenergic, and cytokine systems that lead to series of adaptive changes within the myocardium, collectively referred to as left ventricle remodelling. These changes include :

– Myocyte hypertrophy

– Alteration in the contractile properties of myocyte

– Progressive loss of myocyte through necrosis, apoptosis

– β-adrenergic desensitization

– Abnormal myocardial energetic and metabolism

– Reorganization of extracellular matrix with dissolution of organized structural collagen weave , replacement with an interstitial collagen matrix that does not provide structural support to the myocytes

Page 11: Left heart failure and right heart failure because of

Left ventricle remodelling on

macrostructural level

• Change of LV geometry from ellipsoid to spherical shape – an increase of meridional wall stress

• Increase in end-diastolic volume – LV wall thinning. Together with the increased afterload leads to decreased stroke volume

• High end-diastolic wall stress leads to– Hypoperfusion of the subendocardium – worsening of LV

function

– Increased oxidative stress

– Sustained expression of wall-stretch-activated genes (AII, TNF)

• Because of increased sphericity the papillary muscles are pulled apart, resulting in incompetence of the mitral valve – mitral regurgitation – further hemodynamic overloading of the ventricle

Page 12: Left heart failure and right heart failure because of

Mechanical burdens that are engendered by

left ventricle remodelling can be expected to

lead to

• decreased forward cardiac output

• increased left ventricle dilatation

(stretch)

• increased hemodynamic overloading

Page 13: Left heart failure and right heart failure because of

Different forms of left ventricle overload

Pressure (systolic)

overload

– Increased afterload

– Aortic stenosis,

hypertension

– Myocardial hypertrophy

with minimal dilatation

Volume (diastolic)

overload

• Increased preload

• Mitral or aortic

regurgitation

• Left ventricle

dilatation

Page 14: Left heart failure and right heart failure because of

Clinical symptoms and physical signs

of the heart failure

• Fatigue

• Dyspnoea

• Tachycardia

• Cyanosis

• Pulmonary congestion

• Phlebohypertension

• Hepatomegaly

• Congestion of the kidney

• Other symptoms

Page 15: Left heart failure and right heart failure because of

Clinical symptoms of the heart failure

• Fatigue– The consequence of low cardiac output, but other non-

cardiac co-morbidities (anaemia, musculoskeletal abnormalities) also contribute to this symptom

• Dyspnoea (the most important mechanism is the pulmonary congestion with accumulation of interstitial or intraalveolar fluid. Other factors are reduction in pulmonary compliance, increased airway resistance, respiratory muscle weakness, and impaired sensitivity of respiratory centre) – Clinical manifestations:

– Effort dyspnoea

– Dyspnoea at rest

– Orthopnoea: Dyspnoea occurring in the recumbent position.

– Acute episodic shortness of breath

– Cheyne-Stokes respiration

Page 16: Left heart failure and right heart failure because of

Acute and/or periodic forms of

dyspnoea

• Paroxysmal nocturnal dyspnoea– Acute episodes of severe

shortness of breath and coughing that occur at night and awaken the patient from sleep, usually 1-3 after the patient retires.

– It manifests by coughing or wheezing, possible because of increased pressure in the bronchial artery leading to airway compression, along with interstitial pulmonary oedema.

– It does not improve in upright position

– It can be associated with hypertension, aortic vitium, dilated cardiomyopathy.

• Cheyne-Stokes respiration

– Caused by diminished sensitivity of respiratory centre to arterial PCO2.

– In the apnoeic phase the patient can be unconscious,

Page 17: Left heart failure and right heart failure because of

Cyanosis

• Bluish colour of the skin and mucous

membranes resulting from an increased quantity

of reduced haemoglobin( exceeds 40 g/l) in the

small blood vessels of those areas.

• It is usually most marked in the lips, nail beds,

ears, and malar eminences

• Central cyanosis can be detected reliably when

arterial O2 saturation has fallen to 85% (in dark-

skinned persons 75%)

Page 18: Left heart failure and right heart failure because of

Clinical signs and symptoms of

pulmonary congestion

– Decreased vital capacity of the lung because of interstitial pulmonary oedema

– Central cyanosis (inhibited gas exchange)

– Dyspnoea

– Coughing

– Brownish sputum (epithel cells containing hemosiderin pigments), eventually haemoptysis

– Ronchi, wheezing, crackles

– Accentuated pulmonary component of second heart sound

– Dilated pulmonary veins on the X-ray

Page 19: Left heart failure and right heart failure because of

Clinical signs and symptoms of right-

sided heart failure

• Gärtner’s sign: The veins of the hand remain dilated by the

elevation of the arm to the level of the left atrium

• Distension of the external jugular vein :elevated jugular

venous pressure.

• Positive abdomino-jugular reflux: With sustained pressure

on the abdomen the jugular venous pressure becomes

abnormally elevated.

• Hepatomegaly. The enlarged liver is frequently tender.

Jaundice and ascites are late finding in heart failure, results

from impairment of hepatic function secondary to hepatic

congestion and hepatic hypoxia.

• Proteinuria

• Anorexia, nausea, and early satiety associated with

abdominal pain and fullness relates to oedema of bowel wall

and/or to the congested liver.

Page 20: Left heart failure and right heart failure because of

Oedema

• Oedema: : accumulation of fluid in the interstitial

space. Residual imprint of fingers following

application of pressure.• Latent oedema: (less than 5-6 l fluid retention). Identification:

measurement of body weight in the morning and in the

evening and/or compare the amount of the urine during the

day and during the night.

• Manifest oedema: usually symmetric, and occurs

predominantly in the ankles and pretibial region in

ambulatory patients. In bedridden patients, oedema may be

found in the sacral area, and the scrotum.

• Differential diagnosis: varicosity, pes planus, deep vein

thrombosis, and v. cava inferior thrombosis)

Page 21: Left heart failure and right heart failure because of

Cor pulmonale

• Definition: dilatation and hypertrophy of

the right ventricle in response to diseases

of the pulmonary vasculature and/or lung

parenchyma (pulmonary heart disease)

• Chronic obstructive lung disease and

chronic bronchitis are responsible for

approximately 50% of the cases of cor

pulmonale in developed countries

Page 22: Left heart failure and right heart failure because of

Aetiology of chronic cor pulmonale

• Diseases leading to hypoxic vasoconstriction– Chronic bronchitis

– COPD

– Cystic fibrosis

– Chronic hypoventilation• Obesity

• Neuromuscular diseases

• Chest wall deformities

– Living at high altitudes

• Diseases causing occlusion of the pulmonary vascular bed– Recurrent pulmonary

thromboembolism

– Primary pulmonary hypertension

– Venoocclusive disease

– Collagen vascular disease

– Drug-induced lung disease

• Parenchymal pulmonary diseases– Chronic bronchitis

– COPD

– Bronchiectasis

– Idiopathic pulmonary fibrosis

– Sarcoidosis

– Pneumoconiosis

Page 23: Left heart failure and right heart failure because of

Pathophysiology of cor pulmonale

Pulmonary disease

Pulmonary hypertension

Right ventricle dilatation and

hypertrophy

Right ventricle failure

Secondary to

alteration of gas

exchange

- Hypoxia

- Hypercapnia

- Acidosis

Alteration in RV

volume overload

-Exercise

-Heart rate

-Polycythaemia

-Salt and water

retention (low CO)

Page 24: Left heart failure and right heart failure because of

Symptoms and signs of cor pulmonale

• Dyspnoea - result of the increased work of breathing or altered respiratory mechanics

• Effort-related syncope – because of the inability of the RV to deliver blood adequately to left side of the heart

• Abdominal pain and ascites

• Lower extremity oedema – secondary to neurohormonal activation, elevated RV filling pressure, or increased levels of carbon dioxide and hypoxia, which can lead to peripheral vasodilatation

• RV heave palpable along the left sternal border or in the epigastrium

• A systolic pulmonary ejection click to the left of the upper sternum

• Holosystolic murmur of tricuspidal regurgitation (the intensity of the murmur increases with inspiration)

• Cyanosis – late finding in cor pulmonale