ISCHAEMIC HEART DISEASE Pathophysiology And Stable Angina Pectoris
JD MarxDepartment of Cardiology
University of the Free State
DefinitionThe blood supply to the myocardium
is insufficient to comply fully with physiological needs of the heart
muscle.
Pathophysiology Blood supply - epicardial vessels with
perforating branches Blood flow from epicardium to
endocardium
Pathophysiology Control of blood flow
› Perfusion in diastoly› Oxygen extraction maximal O2 supply can
only be increased by increasing bloodflow› Humeral factors important - ADENOSIN
Oxygen demand Heart rate Blood pressure Myocardial
contractility
Oxygen supply Coronary bloodflow
› Duration of diastoly› Coronary perfusion
pressure› Coronary vasomotor
tone Oxygenation
› Haemoglobin› Oxygen saturation
PathophysiologyFactors influencing myocardial oxygen
supply and demand
SUPPLY DEMAND
O2-Carrying Capacity
Coronary blood flow
Heart Rate Contractility
Systolic wall tension
Vascular resistance Diastolic
phase
Metabolic control
Auto-regulation
Extravascular compressive
forces
Humoral factors
Neuralcontrol
PathogenesisCauses of vessel obstruction
Fixed lesions› Atherosclerosis› Arteritis› Embolization
Dynamic narrowings› Spasm
Pathogenesis
Atherosclerosis is by far the most common cause of obstruction in
patients with IHD
PathogenesisBirth of Plaque
PathogenesisPlaque progression
PathogenesisPlaque rupture
Fixed factors Family history Gender - male Age
Modifiable factors Smoking Hypertension Hypercholesterolemia Diabetes Mellitus Obesity Inactivity Stress
PathogenesisRisk factors for Atherosclerosis
Clinical Presentation
Stable angina pectoris
Acute Coronary Syndromes› Unstable Angina Pectoris› Non ST-segment elevation myocardial infarction› ST-segment elevation myocardial infarction
Arrhythmias
Sudden death
Ischaemic Cardiomyopathy with LV failure
of patients with Ischaemic Heart Disease
Symptomatic Presentation
The patients most often present with chest pain which should clinically evaluated!
of patients with Ischaemic Heart Disease
Symptomatic Presentation
ANGINA PECTORISTypical chest pain caused by ischaemic myocardium
Chest Pain
Clinically patients with angina pectoris present with:
› Stable Angina Pectoris› Acute Coronary Syndromes
Symptomatic PresentationChest Pain
Chest pain resulting from a specific other disease process
› Pericarditis› Pleuritis› Radicular or neural pain› Musculoskeletal pain› Gastroinstestinal pain› Other
Symptomatic PresentationChest Pain
Atypical chest pain› The chest pain is not typical of any clinical
disease entity
› Several special tests necessary to evaluate
Symptomatic PresentationChest Pain
Angina PectorisSTABLE ANGINA PECTORIS
Diagnosis: › Clinical diagnosis: emphasis on history› Angina with stable pain pattern
Confirmed by:› Resting ECG› Stress ECG› Isotope perfusion study› Coronary angiography
Angina PectorisExercise Stress Test
Angina PectorisIsotope Stress Test
Exercise Rest
Angina PectorisAngiogram
LCA RCA
Angina PectorisTREATMENT
Conservative treatment: General treatment
› Aspirin
Anti-anginal medication› Nitrates› β-blockers› Calcium antagonists
Disease Modifying Therapy› Statins› ACE Inhibitors
Interventional treatment: Coronary angioplasty ( PTCA ) Coronary Artery Bypass Graft Surgery ( CABG )
Thank you