Pathogenesis of cardiac symptoms Dr Rehab F Gwada

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: 1 venous 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 ? • • • 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. • 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 30 mm. Hg Interstitial tissue 25 mm. Hg Venous end capillaries 10 -15 mm. Hg

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 • 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 • Decreased CO in HF • Baroreceptors Dysfunction

In right-sided heart failure • • 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: üReduce capacity for ventilation üstiffening of the lungs ü 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: • • Appear in the dependent parts of the body(L. L) Pitting Precedes appearance of ascites( abdominal enlargement ) Bilateral

Cyanosis • Cyanosis is bluish discoloration of skin, nail beds and mucous membranes as a result from insufficient oxygenation , when arterial reduced Hb. Exceeds 5 g/d. L(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 Peripheral cyanosis • Central cyanosis is caused by diseases of the heart or lungs or by abnormal hemoglobin • may be seen in heart failure, , exposure to cold temperatures and diseases of blood circulation. • Lead to Sa. O 2 , the aortic blood carrying reduced hemoglobin • Due to oxygenated blood flow through the peripheries. • Noticed in tongue , lips, ear lobes , conjunctiva of the eyes • Noticed in fingers, cheeks, nose, and outer Warm extremities • • • There may be breathlessness, shallow or rapid breathing areas of the lips. 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 • 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.

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