Heart PT 2 Flashcards
(179 cards)
Rhythmic disorders are most caused by?
ischemia
What is sick sinus syndrome and what does it cause
SA node is damaged d/t ischemia => causing bradycardia
What is a-fib? What can it cause and describe the heartbeat?
-
Sporadically depolarizing atrial myocytes d/t atrial dilation, causing variable transmission through the AV node, which can cause clots and an irregular irregular heartbeat
- Thus, give blood thinners
What is an AV block?
Fucked up AV node causes abnormal heart rhythm that causes the heart to beat too slowly (heart block)
What is the difference between first, second and third degree heart block?
- First degree heart block has a prolonged PR interval
- Second degree heart block has intermittent transmission
- Third degree heart block has complete heart failure.
What causes arrhythmias?
- Abnormalities in structure of gap junction/ spatial relationship,
- Ischmia/hypertrophy/ inflammation,
- Amyloid deposits or scarring/
- Genetics (AD)
What is the most common inherited arrhythmogenic disease?
- Long QT syndrome: arrythmias d/t with too much prolongation of cardiac repolarization d/t K+/Na+ channelopathy
Most common inherited arrhythmogenic disease have what pattern of genetic inheritance?
AD
What are 4 genes implicated in long QT syndrome?
- KCNQ1
- KCNH2
- SCN5A
- CAV3
Long QT syndrome is associated with ____ of K+ channels or _____ of Na+ channels
LOF of K+
GOF of Na+
arrhythmias associated with short repolarization intervals.
What is this and what can patients experience
Short QT syndrome
palpitations, syncome, sudden cardiac death
What syndrome has ECG abnormalities (ST-elevation; RBBB) without a structural defect in the heart?
What do they present with?
Brugada syndrome;
-syncope/SCD during rest, sleep or large meals
Pablo came into ER and was pronounced death after an unexpected cardiac cause within 24 hours of onset of symptoms. What can we diagnose this patient as? Are symptoms always required?
- Sudden cardiac death (SCD)
- No
Pablo was diagnosed with SCD (sudden cardiac death). SCD is due to?
fatal arrhythmia d/t damage of the myocardium d/t ischemia.
Pablo, who suffered from SCD, was able to be resuscitated. Based on statistics, what will his lab/ECG show?
- 80-90% of resuscitated patients have NO lab or ECG changes because they have no long-term damage.
What is the leading cause of SCD?
- CAD in 80-90% of patients: patients will usually have >75% stenosis of 1 or more of 3 main coronary arteries.
What is OFTEN first sign of IHD (ischemic heart disease)?
Sudden cardiac death :(
Hypertrophy of the heart is an adaptive response to chronically elevated pressures; with continued overload, the result can be
dysfunction, dilation, CHF or SCD.
What criteria are required to diagnose a patient with left-sided hypertensive heart diseases (systemic hypertensive heart disease)?
- 1. HTN
- LV hypertrophy that is concentric w no other probs => decrease lumen size
In systemic hypertensive heart disease, how will the heart adaptively response?
- Wall of LV thickens to more than 1.5 cm => weighs more than 500 grams.
In Systemic (left-sided) HHD as the LV wall continues to increase in thickness, what associated morphological changes occur?
- ↑ interstitial CT –> stiffness = impaired diastolic filling; LV does not fill with blood –> LEFT ATRIAL ENLARGEMENT => a-fib
In many pt’s, systemic HHD comes to attention due to what signs/sx’s?
- L atria enlarged => causes A-fib => leads to CHF, a risk factor for SCD.
Isolated pulmonary (right-sided) HTN heart disease (cor pulmonale) arises in the setting of what?
- Pulmonary HTN
What is the most common cause of pulmonary HTN?
- Left-sided heart disease.










