Cardiac Flashcards
Review the normal changes of pregnancy affecting:
- Blood volume
- Blood volume
- Blood volume peaks 32 weeks
- RBCs production rise less than plasma → physiologic anemia, nadir at 32 wks
Review the normal changes of pregnancy affecting:
- Heart
- Displaced upward by diaphragm and rotated on long axis to the right
- Cardiac output - increased by 30 - 50 % by 20 wks
- first due to stroke volume → later on due to HR
- Heart rate
- Increases early 1st tri → slowly rises throughout pregnancy → resting HR may be 15-20 beats/minute above baseline by middle 3rd tri
- Mild resting tachycardia is normal
Review the normal changes of pregnancy affecting:
- Great vessels and arterial and venous vascular bed
- Systemic vascular resistance decreases (decreased afterload) → increase in CO does not completely compensate → drop in arterial blood pressure (as early as the 7th week)
Summary of physiologic changes - state whether each of the following increase or decrease:
- Stroke volume (SV)
- Heart rate (HR)
- Cardiac output (CO)
- Preload
- Systemic vascular resistance
- Afterload
- INCREASE: SV, HR, CO, preload
- DECREASE: systemic vascular resistance, afterload
What patient position allows for the best cardiac output?
- Left lateral decubitus
Supine position can lower cardiac output by ____%
25-30%
(compression of the IVC by gravid uterus)
What happens to cardiac output during labor?
- Progressively increases → more blood in circulation due to uterine contraction (autotransfusion)
- Also due to pain/anxiety
- Valsalva in 2nd stage: +50%
- Immediately PP: +80% (above baseline term pregnancy values)
Describe normal changes of pregnancy that may mimic signs of cardiac disease
- Palpitations
- Shortness of breath with exertion
- Chest pain
Indications for further cardiac diagnostic testing in pregnant patient
- History of known cardiac disease
- Symptoms in excess of those expected in a normal pregnancy
- Pathologic murmur
- Evidence of heart failure on physical examination
- Arterial oxygen desaturation in the absence of known pulmonary disease
List findings on physical assessment that are almost always indicative of heart disease
May indicate heart disease
- Cyanosis
- Clubbing of fingers
- Persistent neck vein distension
- Systolic murmur grade 3/6 or greater
- Diastolic murmur
- Cardiomegaly
- Persistent arrhythmia
- Persistent split second sound
- Criteria for pulmonary hypertension
Clinical symptoms of heart disease during pregnancy
(as opposed to normal changes that mimic heart disease)
- Progressive dyspnea or orthopnea
- Nocturnal cough
- Hemoptysis
- Syncope
- Chest pain
Describe the times of greatest risk during the perinatal cycle for a woman with heart disease
- Intercurrent events superimposed on pregnancy are usually responsible for acute decompensation.
- Antepartum period - most common of these are febrile episodes
- Labor and delivery - hemodynamic instability
- Post partum - “perfect storm” of volume loading, tachycardia, and increased afterload; each of these may contribute to destabilization
- ***Most heart failure occurs peripartum (per powerpt)
Risks to pregnancy (parent/fetus) when pregnant parent has heart disease
- Parental arrhythmias
- Heart failure
- Preterm birth
- Fetal growth restriction
- Small but significant risk of maternal and fetal mortality
Identify common, normal EKG changes that occur during pregnancy
- Mean QRS can shift leftward due to elevation of the diaphragm
- May return to the right as the fetus descends at pregnancy end
- Minor ST-segment and T-wave changes may be observed
- Less often, T-wave inversions may appear transiently in the left precordial leads.
- Seldom of sufficient magnitude to raise the question of ischemic heart disease
Describe the potential effect of heart disease on the fetus
