Cardiac Disorders and 12 Lead EKG

Question 1

Ischemic Heart Disease

Answer 1

Reflects the presence of atherosclerosis in the coronary arteries (Coronary Artery Disease-CAD)

Question 2

Manifestations of Ischemic Heart Disease

Answer 2

Angina Pectoris, Acute Myocardial Infarction, Sudden Death (likely caused by cardiac dysrhythmias)

Question 3

Risk Factors for CAD

Answer 3

*male gender and increasing age* Hypercholesterolemia, Hypertension, Smoking Diabetes mellitus, obesity, sedentary life style, family history of premature CAD.

Question 4

Caused by an imbalance between coronary blood flow (supply) and myocardial oxygen consumption (demand) which can precipitate ischemia

Answer 4

Angina Pectoris

Question 5

What is the most common cause of myocardial ischemia?

Answer 5

Atherosclerosis

Question 6

What happens when there is an extreme imbalance between coronary blood flow (supply) and myocardial oxygen consumption (demand)?

Answer 6

Congestive heart failure-(CHF), electrical instability & cardiac dysrhythmias, and myocardial infarction (MI) can result.

Question 7

how does Angina Pectoris present clinically?

Answer 7

Retrosternal chest pain (described as pressure or heaviness), discomfort typically radiates to the neck, left shoulder, left arm, or lower jaw. Usually induced by physical exertion, emotional tension, and cold weather.

Question 8

how is angina pectoris diagnosed?

Answer 8

Electrocardiography: ST depression (> 1mm) & T wave inversion Echocardiography: wall motion abnormalities & predicts location of obstructing lesion Nuclear Stress Imaging: assesses coronary perfusion by defining vascular regions in which stress-induced coronary blood flow is limited. Can also est. LV size & function Coronary Angiography: Gold standard. Determines anatomic extent of CAD & LV function (EF).

Question 9

what is the gold standard for diagnosing angina pectoris?

Answer 9

Coronary Angiography: Gold standard. Determines anatomic extent of CAD & LV function (EF).

Question 10

what are some treatment options for angina?

Answer 10

Life style modification: Smoking cessation, maintenance of ideal body weight, regular aerobic exercise.

Pharmacologic therapy: Antiplatelet drugs, B-blockers, Calcium channel blockers, ACE inhibitors & Nitrates

Revascularization: Coronary Artery Bypass Grafting (CABG)& Percutaneous Transluminal Coronary Angioplasty PTCA

Question 11

Nearly all MIs are caused by …..

Answer 11

thrombotic occlusion of a coronary artery

Question 12

Stenosis > __% required to produce Angina pectoris

Answer 12

70

Question 13

diagnosis of an MI requires 2 out of 3 criteria. What are they?

Answer 13

1) clinical history of angina pectoris
2) serial electrocardiographic changes indicative of myocardial infarction (ST segment elevation or ST depression, T wave inversion, bundle branch block)
3) rise and fall of serum cardiac enzyme markers: Troponin T or I-increase within 4 hours after myocardial injury; CK-MB is less specific

Question 14

what are the symptoms of an MI?

Answer 14

Same as Angina pectoris On Physical exam: Anxiety, sinus tachycardia, hypotension (caused by left or right ventricular dysfunction or cardiac dysrhythmias) Moist rales representing CHF (due to LV dysfunction) Cardiac murmur may reflect ischemic mitral regurgitation.

Question 15

what are some treatment options for an MI?

Answer 15

Aspirin IV Morphine: pain relief and decrease the stimulus to catecholamine release and increases in myocardial oxygen requirements.

Thrombolytic Therapy: Tissue plasminogen activator (t-PA, streptokinase) within 30-60 min of hospital arrival.

Coronary Angioplasty: within 1-2 hours CABG: reperfusion achieved more quickly with Thrombolytics or PTCA, emergent CABG reserved for patients who’s anatomy precludes PTCA, failed angioplasty, infarct related ventricular septal defect or MR

Adjunctive Medical Therapy: Heparin IV, Beta blockers, ACE inhibitors, nitrate therapy

Question 16

what are some anesthetic considerations for MIs?

Answer 16

High risk patients should be optimized on preoperative anti-ischemia and anti-hypertension therapy

Control balance between myocardial oxygen supply/demand especially during induction & emergence.

Quick Intubations

Monitors: ECG, Pulmonary artery catheter, and Transesophageal echocardiography for early detection of ischemia

Question 17

What are some examples of valvular heart disease?

Answer 17

Mitral Stenosis

Mitral Regurgitation

Mitral Valve Prolapse

Aortic Stenosis

Aortic Regurgitation

Tricuspid Regurgitation

Question 18

How do you evaluate valvular heart disease?

Answer 18

Assess severity of disease

Assess degree of impaired contractility

Assess for the presence of associated major organ system disease (pulmonary, renal, hepatic)

Recognize compensatory mechanisms for maintaining cardiac output (> sympathetic ns activity or ventricular hypertrophy)

Define exercise tolerance to evaluate cardiac reserve

Assess for CHF

Assess for murmurs

Question 19

AP valves open; so murmurs heard are AP stenosis or MT insufficiency (AS, PS, MR, TR)

Answer 19

systolic murmur

Question 20

MT valves open; so murmurs heard are MT stenosis or AP insufficiency (MS, TS, AR, PR)

Answer 20

diastolic murmur

Question 21

symptoms of mitral stenosis

Answer 21

dyspnea on exertion, orthopnea, PND from LV dysfunction (if AR and MR also present  significant LV dysfunction)

Question 22

Mitral stenosis increases pressure where?

Answer 22

Left Atrium

Question 23

how is mitral stenosis diagnosed?

Answer 23

by echocardiography to assess valve orifice

Question 24

Transvalvular pressure gradient > ___ mmHg=severe MS

Answer 24

Transvalvular pressure gradient > 10 mmHg=severe MS

Question 25

treatments for mitral stenosis

Answer 25

Prophylaxis against infective endocarditis Diuretics with mild symptoms