68. Angina pectoris, chronic ischemic heart disease, sudden cardiac death.

Umbrella term for all conditions characterized by ischemia of myocardium.

- Almost always caused by atherosclerosis of coronary artery

Coronary artery disease = IHD

What is ischemic heart disease? (IHD)

Cardiomyocytes generate almost all of their energy from oxidative phosphorylation.

(They are dependent on constant blood flow)

Why are cardiomyocytes especially injured under ischemia?

90% due to: Coronary artery disease (atherosclerosis)

10% due to: abnormally increased demand, diminished blood volume, diminished oxygen supply, diminished oxygen-carrying capacity of the blood

What are the causes of cardiac ischemia?

Ischemia of the heart due to atherosclerotic plaques.

Can be acute and chronic

What is coronary artery disease? (CAD)

When atherosclerotic plaque occludes more than 70% of the lumen:

"Critical stenosis"

When does symptoms of coronary artery disease appear?

The same risk factors for developing atherosclerosis:

- Hypertension

- Diabetes mellitus

- Dyslipidemia

- Obesity

Risk factors for developing CAD?

MI, angina pectoris, chronic ischemic heart disease, sudden cardiac death

Which diseases fall under the ischemic heart disease umbrella term?

The name for the characteristic pain associated with the different types of ischemic heart disease

What is angina pectoris?

Stable angina, prinzmetal's angina, unstable angina

Which are the most important forms of angina pectoris?

Stable angina

Classic manifestation of chronic ischemic heart disease?

A critical stenosis is present

- In rest the myocardium is sufficient perfused

- During exercise the perfusion becomes insufficient which caused an angina pectoris

- 70% of coronary artery is occluded

What is stable angina?

Rest, application of nitro-glycerine

How can the symptoms of a stable angina be relieved?

Vasodilator

What is nitro-glycerine?

Pain due to a strong vasospasm of an epicardial artery, wich decreaes the perfusion of blood to the heart. The pain is unrelated to physical activity, heart rate or blood pressure

What is Prinzmetal's angina?

Angina pectoris can occur even at rest. Occurs due to a thrombosis stuck in a plaque, which is kinda loose so sometimes it blocks the artery and sometimes not

What is an unstable angina?

Gives a warning sign that an AMI may occur in the near future

Why is an unstable angina unstable?

A progressive heart failure, occurs due to ischemic myocardial damage caused by a previous MI or severe coronary artery disease.

The rest of the healthy myocardium tries to compensate for the damaged myocardium

What is chronic ischemic heart disease?

Caused by ischemic damage to the myocardium.

Causes:

1) Long-term chronic ischemic heart disease

2) Previous MI

May lead to heart failure

Ischemic cardiomyopathy?

Left ventricular hypertrophy and dilation

How can the healthy myocardium compensate for the damaged in CIHD?

Left ventricular hypertrophy and dilation of the healthy myocardial tissue, fibrosis of the damaged myocardium

Macroscopy of CIHD

Myocardial hypertrophy, fibrosis, diffuse subendocardial vacuolization

Microscopy of CIHD

Unexpected death from cardiac causes. Happens early after the onset of symptoms, and can also happen without symptoms

What is sudden cardiac death?

- Chronic ischemic heart disease

- AMI

- Cardiomyopathy

- Myocarditis

What can be the causes if sudden cardiac death?

A lethal arrhythmia: ventricular fibrillation or asystole

What is always the actual cause of death in any heart disease?