CHRONIC COR PULMONALE. Cor pulmonale 1. Acute cor pulmonale 2. Chronic cor pulmonale

CHRONIC COR PULMONALE

Cor pulmonale

1. Acute cor pulmonale 2. Chronic cor pulmonale

Cor pulmonale

Acute cor pulmonale usually refers to the development of acute pulmonary hypertension and right ventricular overload from a massive pulmonary thromboembolic event, with subsequent development of right ventricular dilation

Chronic cor pulmonale: Definition

Pulmonary arterial hypertension resulting from diseases affecting the structure and/or the function of the lungs; pulmonary arterial hypertension

results in right ventricular enlargement (hypertrophy and/or dilatation) and may lead with time to right heart failure

(Weitzenblum, 2003)

Chronic cor pulmonale: key-point

- Right ventricular dilation or hypertrophy in chronic cor pulmonale is a direct compensatory effect of chronic pulmonary vasoconstriction and subsequent pulmonary artery hypertension that leads to increased right ventricular work and stress.

- When the right ventricle can no longer compensate through dilation or hypertrophy, right ventricular failure occurs.

Chronic cor pulmonale: Old Definitions

Hypertrophy of the right ventricle resulting form diseases affecting the structure and/or function of the lungs (WHO, 1963)

Hypertrophy alteration in the structure and function of the right ventricle (revision, 1970)

Pulmonary hypertension: Definition

Pulmonary hypertension complicating chronic respiratory disease is generally defined by the presence of a resting mean pulmonary artery pressure (PAP) > 20 mm Hg.

This is slightly different from the definition of primary pulmonary hypertension (PAP> 25 mmHg).

Definition

In young (< 50 years) healthy subjects PAP is most often between 10–15 mm Hg.With aging there is a slight increase in PAP, by about 1 mm Hg/10 years.

A resting PAP > 20 mm Hg is always abnormal.

In the “natural history” of COPD, pulmonary hypertension is often preceded by an abnormally large increase in PAP during exercise, defined by a pressure> 30 mm Hg for a mild level of steady state exercise.

The term “exercising” pulmonary hypertension has been used by some authors, but the term “pulmonary

hypertension” should be reserved for resting pulmonary hypertension.

Aetiology

Aetiology

Aetiology

There are three major groups of diseases which may lead to cor pulmonale:

those characterised by a limitation to airflow (COPD and other causes of chronic bronchial obstruction)

those characterised by a restriction of pulmonary volumes from extrinsic or parenchymatous origin (restrictive lung diseases)

those where the relatively well preserved mechanical properties of the lungs and chest wall contrast with pronounced gas exchange abnormalities which are partially explained by poor ventilatory drive (respiratory insufficiency of “central”origin).

Aetiology

Obstructive lung diseases:

COPD (chronic obstructive bronchitis, emphysema and their association) (80-90% of cases)

Asthma with irreversible airway obstruction

Bronchiectasis

Bronchiolitis obliterans

Aetiology

Restrictive lung diseases:

Kyphoscoliosis

Idiopathic pulmonary fibrosis

Pneumoconiosis

Aetiology

Respiratory insufficiency of “central” origin:

Central alveolar hypoventilation

Obesity-hypoventilation syndrome (formerly, “Pickwickian syndrome”)

Sleep apnea syndrome

All of the following diseases are relatively frequent causes of cor pulmonale, EXCEPT:

A. Idiopathic pulmonary fibrosisB. Bacterial pneumoniaC. PneumoconiosisD. Sleep apneaE. Kyphoscoliosis

All of the following diseases are relatively frequent causes of cor pulmonale, EXCEPT:

A. Idiopathic pulmonary fibrosisB. Bacterial pneumoniaC. PneumoconiosisD. Sleep apneaE. Kyphoscoliosis

Some COPD patients with pulmonary hypertension will never develop right heart failure:

A. TrueB. False

Some COPD patients with pulmonary hypertension will never develop right heart failure:

A. TrueB. False

Pathophysiology

Anatomic factorsDestruction or obstruction of the pulmonary vascular bed

Functional factorsAlveolar hypoxia Acute hypoxic pulmonary vasoconstriction Remodeling of the vascular bed due to chonic hypoxemia

Hypercapnia and acidosisHyperviscosityHypervolemia secondary to polycythemia

Mechanical factorsCompression of alveolar vessels

Recognized mechanisms of pulmonary hypertension in chronic obstructive pulmonary disease are all of the followings, EXCEPT:

A. Pulmonary vascular remodeling resulting from chronic alveolar hypoxia

B. Increased pulmonary vascular resistance

C. Elevated pulmonary capillary wedge pressure

Recognized mechanisms of pulmonary hypertension in chronic obstructive pulmonary disease are all of the followings, EXCEPT:

A. Pulmonary vascular remodeling resulting from chronic alveolar hypoxia

B. Increased pulmonary vascular resistance

C. Elevated pulmonary capillary wedge pressure

Clinical Assessment

The clinical signs occur late, being observed at an advanced stage of the disease far after the development of

pulmonary hypertension. Peripheral (ankle) oedema is the best sign of RHF but it is not

specific and can arise from other causes; in some patients with pulmonary hypertension, it does not occur at all.

A murmur of tricuspid regurgitation, suggesting right ventricular dilatation, is a very late sign in respiratory patients.

Accentuation of the pulmonary component of the second heart sound is only observed in patients with severe pulmonary hypertension.

Clinical Assessment: features of frank right heart failure

- Ascites and peripheral edema

- Pulsus paradoxus (a decrease of >10 mm Hg in systemic systolic BP during inspiration)

- Prominence of the jugular veins

- Sustained impulse along the lower left sternal margin (arising from RV enlargement)

NB. Cardiac findings may be obscured during auscultation by chest hyperinflation and by rotation of the heart in patients with COPD

Diagnostic techniques

Chest radiography ECG Echo

Radionuclide assessment of RV EF RV dimensions measured by MRI

Diagnostic techniques

Chest radiography

↑ Diameter of the right descending PA on posteroanterior projection

↑ Diameter of the left descending PA on left lateral projection

Loss of retrosternal airspace on lateral films (owing to RV hypertrophy)

RV silhouette often assumes lobular appearance

Diagnostic techniques: chest radiography

Diagnostic techniques

Chest radiography ECG Echo

Radionuclide assessment of RV EF RV dimensions measured by MRI

ECG (high specifity, but low sensitivity)- Right ventricular hypertrophy:R.A.D.R or R’>S in V1R<S in V6R in V1 + S in V5 or V6 = 10 mmR in V1 = 7 mm (15 mm with RBBB)RA enlargement

-S1S2S3 syndrome-Incomplete or complete RBBB-Inverted, biphasic, or flattened T waves in precordial leads- Depressed ST segments in leads II, III, aVF

Case 1

A 76-year old man admitted for dyspnea

Case 1

A 76-year old man admitted for dyspnea

Case 2

A 60-year old woman with dyspnea and pulmonary hypertension in the setting of sarcoidosis

Case 2

A 60-year old woman with dyspnea and pulmonary hypertension in the setting of sarcoidosis

Peripheral (ankle) oedema is the best clinical sign of cor pulmonale:

A. TrueB. False

Peripheral (ankle) oedema is the best clinical sign of cor pulmonale:

A. TrueB. False

A normal ECG does not exclude the presence of cor pulmonale :

A. TrueB. False

A normal ECG does not exclude the presence of cor pulmonale :

A. TrueB. False

The non-invasive diagnosis of pulmonary hypertension is presently based on Doppler echocardiography :

A. TrueB. False

The non-invasive diagnosis of pulmonary hypertension is presently based on Doppler echocardiography :

A. TrueB. False

Treatment

FEV 1

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f val

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t age

25)

Age (years)Adapted from Fletcher C et al. Br Med J. 1977;1:1645–1648.

COPD Risk and Smoking Cessation

0

25

50

75

100

25 50 75

Death

Disability

Never smoked or not susceptible to smoke

Smoked regularlyand susceptible toeffects of smoke

Stopped smoking at 45 (mild COPD)

Stopped smoking at 65 (severe COPD)

Treatment

Long-term oxygen therapy (LTOT)Vasodilator treatment Other (diuretics, digitalis, phlebotomy)

Indications

AbsolutePa O2 ≤55 mm Hg or Sa O2 ≤88%

In patients with cor pulmonale Pa O2 55–59 mm Hg or Sa O2 ≥89%ECG evidence of P pulmonale, hematocrit >55%, and CHD

Specific IndicationsNocturnal hypoxemia

Sleep apnea with nocturnal desaturation not corrected by constant positive airway pressure or bilevel positive airway pressureNo hypoxemia at rest, but desaturation during exercise or sleep (PaO2 <55 mm Hg)

Treatment Goals

Pa O2 ≥60 mm Hg or Sa O2 ≥90%; Appropriately adjusted O2 dose during sleep and exercise

Same as above

Appropriately adjusted O2 dose during sleep

Long-Term Oxygen Therapy: Guidelines

Appropriately adjusted O2 dose during sleep

Same as above

Treatment

Long-term oxygen therapy (LTOT)Vasodilator treatment Other (diuretics, digitalis, phlebotomy)

Treatment

Vasodilator treatment :

ACEI - ARB (captopril, enelapril, losartan): despite reductions in Ppa, no improvements in RV function and exercise tolerance were detected

CCB (nifedipine, diltiazem):only one third demostrated any reduction in Ppa

Nitrates, prostaglandins (E1 and I2 i.v.), theophylline

Treatment

Long-term oxygen therapy (LTOT)Vasodilator treatment Other (diuretics, digitalis, phlebotomy)

Treatment

Digitalis : contraindicated unless left-sided congestive heart failure present

The cardiac glycosides have been used to manage cor pulmonale for many years.

The evidence, however, does not support (!) the use of digoxin in patients with cor pulmonale unless they have concurrent LV failure or arrhythmia (rapid AF).

Treatment

Phlebotomy :

In polycythemic patients who undergo phlebotomy, the mean Ppa decreases but the cardiac output is generally unaffected.

Although rarely indicated as the sole therapy for cor pulmonale, phlebotomy might be considered for acute decompensation of cor pulmonale accompanied by severe polycythemia, or for patients who remain markedly polycythemic even after continuous oxygen therapy.

Nonetheless, it is not known whether repeated phlebotomies lead to any definite long-term benefits in pulmonary hemodynamics.

LTOT has not significantly modified the life expectancy of COPD patients with cor pulmonale :

A. TrueB. False

LTOT has not significantly modified the life expectancy of COPD patients with cor pulmonale :

A. TrueB. False

LTOT is at present the best treatment of cor pulmonale in COPD patients:

A. TrueB. False

LTOT is at present the best treatment of cor pulmonale in COPD patients:

A. TrueB. False