GMED3009- Cardiac disturbances

Question 1

What does the PQRS indicate?

Answer 1

p wave- atrial depolarization
qrs- ventricular depolarization
t wave- ventricular reploarization

Question 2

Cardiac rythms

Answer 2

1) Sinus rhythm- bradycardia, tachycardia
2) Atrial rhythms- AF, atrial flutter, wandering pacemaker, AT
3) Ventricular rhythms- idoventricular, VT, VF

shockable rhythms- VF and VT- pulseless

Question 3

Classification of arrythmias

Answer 3

second degree (T1)- Pr interval= irregular, R-R interval= irregular
second degree (T2) - Pr interval= regular, R-R interval= regular
third degree (complete)- Pr interval= irregular, R-R interval = regular

Question 3

Classification of arrythmias

Answer 3

second degree (T1)- Pr interval= irregular, R-R interval= irregular
second degree (T2) - Pr interval= regular, R-R interval= regular
third degree (complete)- Pr interval= irregular, R-R interval = regular

Question 4

aetiology of a patient in VT

Answer 4

The most common cause of VT is ischemic heart disease, in which myocardial scar tissue is the leading cause. VT can also be seen in other conditions that create a myocardial scar, such as the following:

● Dilated cardiomyopathy
● Hypertrophic cardiomyopathy
● Surgical incisions in the ventricle

The following can also trigger VT:

▪ Electrolyte deficiencies (e.g., hypokalemia, hypocalcemia, and hypomagnesemia)
▪ Systemic diseases that affect the myocardium (sarcoidosis, systemic lupus erythematous, hemochromatosis, and rheumatoid arthritis)
▪ Sympathomimetic agents, including IV inotropes and illicit drugs such as methamphetamine or cocaine
▪ Digitalis toxicity, which can lead to tachycardia
▪ Drugs that prolong the QT interval (e.g., class IA and class III antiarrhythmic, azithromycin, levofloxacin, and many others); these may cause torsade’s de pointes

Question 5

Pathophysiology of VT

Answer 5

caused by electrical reentry or abnormal automaticity. Myocardial scarring from any process increases the likelihood of electrical reentrant circuits. These circuits generally include a zone where normal electrical propagation is slowed by the scar. Ventricular scar formation from a prior myocardial infarction (MI) is the most common cause of sustained monomorphic VT. VT in a structurally normal heart typically results from mechanisms such as triggered activity and enhanced automaticity.

During VT, cardiac output is reduced as a consequence of decreased ventricular filling from the rapid heart rate and the lack of properly timed or coordinated atrial contraction. Ischemia and mitral insufficiency may also contribute to decreased ventricular stroke output and hemodynamic intolerance.

Hemodynamic collapse is more likely when underlying left ventricular dysfunction is present or when heart rates are very rapid. Diminished cardiac output may result in diminished myocardial perfusion, worsening inotropic response, and degeneration to ventricular fibrillation (VF), resulting in sudden death.

VT is significant because of its unpredictability and potential to cause death. A patient may be stable in VT (for a short time) or unstable with hypotension and no detectable pulse.

Question 6

the typical signs and symptoms of a cardiac patient with VT

Answer 6

Symptoms of VT include the following:
● Palpitation
● Light-headedness
● Syncope
● Chest pain
● Anxiety
Physical examination
During VT, the following may be observed:
▪ Hypotension
▪ Tachypnea
▪ Signs of diminished perfusion, including a diminished level of consciousness, pallor, and diaphoresis
▪ High jugular venous pressure
▪ Cannon a waves (if the atria are in sinus rhythm)

Question 7

the routine medical and nursing care of a patient with VT

Answer 7

Pulseless
● Immediate CPR
● Immediate defibrillation
● Follow ARC flowchart

Hemodynamically stable patient with monomorphic VT is treated differently. The treatment consists of
● Amiodarone
● Infusion of Sotalol
● Synchronized cardioversion

Question 8

nursing care and interventions for this patient, pre and post VT treatment?

Answer 8

● ECG – Monitoring 12 lead
● Vital signs – 5 minutes till stable
● Post Surgical care (angiogram/angioplasty)
● Post VT Care _ monitoring
● Post Cardioversion care – Reperfusion rhythms
● Medication education
● Cardiac care Education
● Diet Changes/life style changes

Question 9

most common cause of VT

Answer 9

myocardial infarction

Question 10

Epinephrine

Answer 10

Nonselective agoinst of all adrenergic receptors