Transcript Pathogenesis of cardiac symptoms

Pathogenesis of
cardiac symptoms
Dr. Rehab F. Gwada
Objectives of the lecture
• Identify the main cardiac symptoms
• Explain pathogenesis of cardiac symptoms
• Differentiated between Cardiac asthma and bronchial asthma
• Understand the mechanism of interstitial fluid formation
• Compare between Peripheral & central cyanosis
The main symptoms of cardiac diseases
Chest
pain
Palpitatio
ns
Edema
Dyspnea
Fatigue
Syncope
Cyanosis
Dyspnea
• Definition :
• Shortness(difficultly) of breathing (SOB)
• types :
1.
2.
3.
4.
Exertional dyspnea
Positional (Orthopnea)
Paroxysmal dyspnea
Acute dyspnea (acute pulmonary edema)
Dyspnea
Shortness(difficultly) of breathing (SOB)
Pathogenesis of Cardiac dyspnoea
• 1-
vital capacity due to
blood in lung
• 2- exaggeration of Hering-Beruer
reflex due to rigid alveali.
• 3- Churchil- Cope reflex in pul.
congestion
stimulate RC
• 4- pulmonary edema
nonfunctioning alveoli
• 5- fatigue of resp. ms. Due to
LCOP
• 6- pleural & pericardial effusion
compression of lung
• 7-Hypoxia
stimulate RC.
Grades of dyspnea
• Grade I: dyspnea on extra ordinary effort
• Grade II: dyspnea on ordinary effort
• Grade III: dyspnea on less than ordinary effort
• Grade IV: dyspnea even at rest.
Ordinary effort is that of the person himself as regard his previous effort
tolerance and usual life style.
Exertional dyspnea:
SOB aggravated by exertional
Cardiac causes:
Coronary artery disease
Congestive heart disease: LSHF
Congenital cyanotic heart disease
Dyspnea may be accompanied by chest discomfort or pain
attack.
(angina) or heart
. Orthopnea : Dyspnea on lying flat (reclining),partially relieved by
sitting
that is due to:
1venous return
2- elevation of diaphragm
lung congestion
Paroxysmal Nocturnal Dyspnea (PND):
- Attacks of dyspnea , sweating & cough with frothy expectoration occurring
during night 1-2 h. after sleep & after a few(10-20) minutes the pt. feels better
& goes back to sleep. symptoms may be relieved by getting out of bed or by
sitting on the side of the bed
- If the condition is accompanied with chest wheezes, it called cardiac asthma
- PND is a specific symptom of LSHF
Acute pulmonary edema:
Severe SOB of acute onset(second- minutes)& short duration (minutes-hours)&
very rapid progressive course
Cardiac asthma is sometimes confused with bronchial
asthma , discuss, and compare ?
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Character
Age
Time of Attack
Duration of attack
Frequency
Dyspnea
Expectoration
Cardiac examination
Chest examination
MORPHINE
ADRINALINE
Cardiac asthma
Bronchial asthma
Cardiac edema
• It is abnormal accumulation of fluid in the interstitial tissues due to a
disturbed mechanism of interstitial fluid formation.
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Technically, edema is classified as a sign, rather than a symptom,
because it is physically observable.
Edema is a common sign of heart disease
Mechanism of interstitial fluid formation
Arteriolar end capillaries
30mmHg
Interstitial tissue
25mmHg
Venous end capillaries
10-15 mmHg
Pathogenesis of cardiac oedema
I- Raised venous hydrostatic pressure
Arteriolar end capillaries
Interstitial tissue
Venous end capillaries
Pathogenesis of cardiac oedema
• II- Increased capillary permeability
• III- Salt and water retention
Pathogenesis of cardiac oedema
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Vasoconstriction and fluid retention produce an increased hydrostatic pressure in the
capillaries.
This shifts the balance of forces in favor of interstitial fluid formation as the increased
pressure forces additional fluid out of the blood, into the tissue.
This results in edema (fluid build-up) in the tissues.
Neurohormonal Activation in CHF and Edema
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Decreased CO in HF
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Baroreceptors Dysfunction
In right-sided heart failure
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Edema commonly starts in the ankles where venous pressure is high due to the
effects of gravity (although if the patient is bed-ridden, fluid accumulation may
begin in the sacral region.)
It may also occur in the abdominal cavity, where the fluid build-up is called
ascites.
In left-sided heart failure
edema can occur in the lungs – this is called cardiogenic pulmonary edema.
Leads to:
Reduce capacity for ventilation
stiffening of the lungs
 Reduces the efficiency of gas exchange by increasing the distance between the
air and the blood.
The consequences of this are dyspnea (shortness of breath), orthopnea and
paroxysmal nocturnal dyspnea.
Characteristics of cardiac edema:
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Appear in the dependent parts of the body(L.L)
Pitting
Precedes appearance of ascites( abdominal enlargement )
Bilateral
Cyanosis
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Cyanosis is bluish discoloration of skin, nail beds and mucous membranes as a result
from insufficient oxygenation , when arterial reduced Hb. Exceeds 5
g/dL(gram/decilliter) .
Normally haemoglobin carries most of the oxygen in blood. This oxygen carrying
capacity of haemoglobin in the blood (present in the arteries) is called oxygen
saturation
Types of cyanosis
Central cyanosis
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Central cyanosis is caused by diseases of the
heart or lungs or by abnormal hemoglobin
Peripheral cyanosis
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may be seen in heart failure, ,exposure to cold
temperatures and diseases of blood
circulation.
Lead to
SaO2 , the aortic blood carrying
reduced hemoglobin
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Noticed in tongue , lips, ear lobes
,conjunctiva of the eyes
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Warm extremities
areas of the lips.
There may be breathlessness, shallow or rapid
breathing
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Due to oxygenated blood flow through
the peripheries .
Noticed in fingers, cheeks, nose, and outer
Cold extremities
Palpitations
• It an abnormal subjective awareness of the heart beats.
• These include feeling a rapid heartbeat, a pounding in the chest, a
fluttering of the heart, being conscious of the beating of the heart, or
feeling missed or skipped beats of the heart
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Heart Causes:
1- Changes in heart rate.(Tachycardia , Bradycardia)
2- Changes in rhythm. (arrhythmias )
3- Changes in force . (heart failure, Cardiomyopathy )
Palpitations
• Depending on the cause, palpitations can be :
A- Short-term and disappear quickly, such as when palpitations occurs
during an anxiety attack.
B- Sudden, severe episodes, such as palpitations that happens with
supraventricular tachycardia.
C- Chronic and ongoing over a long period of time, such as when it is due
to chronic atrial fibrillation.
Palpitations
• Palpitations often occur in conjunction with other symptoms, which vary
depending on the underlying disease, include irregular pulse, chest pain,
shortness of breath, cough, fever, abnormal vital signs, tachypnea and
dyspnea.
Thank you