Ischemic Heart Disease:

(HIGH YIELD NOTES FOR |MBBS|NEETPG|NEXT|INICET|FMGE)

PRESENTATION:

Coronary artery disease (CAD) presents with chest pain that does not change with body position or respiration. CAD is not associated with chest wall tenderness.

When any one of these three features is present, the patient does not have CAD.

Risk factors:

• Diabetes mellitus
• Hypertension
• Tobacco use
• Hyperlipidemia
• Peripheral arterial disease (PAD)
• Obesity
• Inactivity
• Family history

Remember: For family history to be significant, the family member must be young (female relatives < 65, male relatives < 55).

The most common cause of chest pain that is not cardiac in etiology is a gastrointestinal (acid reflux) problem.

CK-MB and troponin levels both rise at 3-6 hours after the start of chest pain. They have nearly the same specificity.

The main difference between CK-MB and troponin is that CK-MB only stays elevated 1-2 days while troponin stays elevated for 1- 2 weeks.

Therefore, CK-MB testing is the best test to detect a reinfarction a few days after the initial infarction.

Tips For MCQ– When the question asks what the most accurate test is, answer CK-MB or troponin. Always the wrong answer: LOH level or LOH isoenzymes.

Myoglobin elevates as early as 1-4 hours after the start of chest pain. Myoglobin is the answer to the question “Which of the follo ing will rise first?” when the choices are all cardiac enzymes.

The definition of acute coronary syndrome (ACS) is as follows:

• Causes acute chest pain
• Can be with exercise or at rest
• Can have ST segment elevation, depression, or even a normal EKG
• Is not based on enzyme levels, angiography, or stress test results
• Is based on a history of chest pain with features suggestive of ischemic disease

TREATMENT:

Aspirin:

The best initial therapy for all cases of ACS is aspirin.

Aspirin can be administered orally or chewed and absorbed under the tongue.

It has an instant effect on inhibiting platelets.

Aspirin alone reduces mortality by 25 percent for acute myocardial infarction and by 50 percent for uunstable angina,” which may become a non-ST segment elevation myocardial infarction (NSTEMI).

Oxygen, nitrates, and morphine should also be administered in acute coronary syndromes, but they do not lower mortality

Angioplasty:

Primary angioplasty means angioplasty during an acute episode of chest pain.

Angioplasty is one type of”percutaneous coronary intervention”(PCI). PCI must be performed within 90 minutes of arrival at the emergency department for an ST segment elevation Ml.

Angioplasty has not been shown to decrease mortality in stable angina more than medical therapy (aspirin, beta blockers, and statins) alone.

Thrombolytics:

If PCI cannot be performed within 90 minutes of arrival in the emergency department, the patient should receive thrombolytics.

Thrombolytics are indicated when the patient has chest pain for < l2 hours and has ST segment elevation in 2 or more leads.

A new left bundle branch block (LBBB) is also an indication for thrombolytic therapy.

Thrombolytics should be given with in 30 minutes of a patient’s arrival in the emergency department with pain.

Statins:

Statin medications, such as atorvostatin, should be given to all patients with an acute coronary syndrome, regardless of what the ECG shows or troponin or CK-MB levels

When Clopidogrel Should be given?

The patient has acute coronary syndrome and is allergic to aspirin.

Clopidogrel is a platelet antagonist but is not to be used routinely in ACS unless there is aspirin allergy or the patient is to undergo angioplasty

When calcium channel blockers (verapamil, diltiazem) Should be give?

The patient has an intolerance to beta blockers, such as severe reactive airway disease (asthma}.
There is cocaine- induced chest pain.
There is coronary vasospasm/Prinzmetal’s angina

Post-MI Discharge Instructions:

All patients post-MI should go home on aspirin, a beta blocker, a statin, and an ACE inhibitor.

COMPLICATIONS OF MYOCARDIAL INFARCTION (MI):

All the complications of myocardial infarction result in hypotension.

Non-ST Segment Elevation Myocardial Infarction:

No thrombolytic use.
Heparin is used routinely.
Glycoprotein Ilb/Illa inhibitors lower mortality, particularly in those undergoing angioplasty.

Following are the indications for CABG:

• Three coronary vessels with > 70 percent stenosis
• Left main coronary artery stenosis > 70 percent