CARDIAC DIAGNOSTICS AND INVASIVE THERAPIES Flashcards
What are the different kinds of Echos?
Rapid Accurate Readily available Portable Noninvasive
Transthoracic echo includes
what?
M-mode
2D cardiac images
Color flow Doppler (checks flow)
Pulse wave Doppler measurements are shown of the aortic valve. High flow rates can be seen during _____ with little flow during ______.
systole
diastole
Echo provides valuable information about cardiac structure and function
Structure? 2
Function? 2
- Chamber size,
- muscle thickness
- Ejection fraction,
- wall motion
What other things will an echo be used for?
4
- Aortic root size (ascending aortic aneurysm)
- Valve structure and function
- Intracardiac blood flow (shunts, pressures)
- Portable (mini) used in the ED for screening for tamponade, effusion, etc.
Transesophageal echo is used for more detailed evaluation of:
Intracardiac thrombus
Valve function
Endocarditis
- How to we use it for Intracardiac thrombus with an Transesophageal echo? 1
- For valve function?2
- For endocarditis? 1
- Prior to direct current cardioversion
- For further evaluation beyond TTE
- For use in the operating room during valve replacement
- Looking for vegetations
What are the three different technologies for abnormal rhythms?
3
- Holter monitor
- Event monitor
- Electrophysiology Studies (EPS)
What are the two kinds of ambulatory cardiac monitors?
Holter and Event
Holter vs Event:
- How long is it worn for?
- What is the patients role?
- What will the monitor usually tell us?
Holter
- Worn for 24 hours
- Patient records a diary of activities and symptoms
- Many times asymptomatic during that time period
Event
- Worn for a month
- Patient triggers the monitor to record during symptoms
- Newer devices will detect significant arrhythmias without patient triggering device to record
Ambulatory cardiac monitors are useful to investigate the following:
6
- Palpitations
- To assess rate control or determine percent of atrial fibrillation
- Syncope
- Intermittent dizziness or lightheadedness that does not seem to be orthostatic
- Suspected bradycardia (shortness of breath or fatigue)
- Evaluate for suspected or known arrhythmias
Electrophysiologic Studies (EPS) are done how?
Use multipolar electrode catheters placed in the venous and/or arterial circulation and advanced to various positions in the heart
- What does it record?
- What kind of disease does it define?
- What does it attempt to do?
- What does it measure?
- Records an internal EKG
- Defines conduction system disease
- Attempts to induce arrhythmias (SVT and VT)
- Measure response to pharmacologic and/or pacing device intervention
Indications for EPS?
5
- Unexplained syncope
- Survivors of sudden cardiac death that was not related to an ischemic event
- Palpitations preceding syncope
- Poorly tolerated episodes of SVT
- Many others…related to uncovering or treating arrhythmias
Electrophysiology Devices?
4
- Pacemakers
- Defibrillators
Therapy for advanced heart failure - Bi-Ventricular pacing
- LVAD
What does a Pacemaker?
Provides electrical stimuli to cause cardiac contraction when intrinsic cardiac activity is inappropriately slow or absent
Pacemakers are the only treatment for what?
What are the different kinds?
4
Bradycardia
- External Pacemaker (Transcutaneous pacemaker)
- Permanent Pacemaker
- Biventricular Pacemaker
- ICD
- External pacemakers are used best when?
- Transcutaneous pacing (TCP) recommended for what?
- Place two pacing pads on the patient’s chest. In what two positions?
- Short term until what?
- in emergencies as a bridge to therapy
- the initial stabilization of hemodynamically significant bradycardia
- either in the anterior/lateral position or the anterior/posterior position (this is painful)
- transvenous pacing or
other therapies can be applied
Placement of a permanent pacemaker involves placement of what?
Where is each connected?
What are the kinds? 2
of one or more pacing wires within the chambers of the heart.
One end of each wire is attached to the muscle of the heart. The other end is screwed into the pacemaker generator.
- Single lead (paces in the ventricle)
- Dual Chamber (can pace in the right atrium or right ventricle)
Where is the generator placed in the pt for a permanent pacemaker?
The generator is placed below the subcutaneous fat of the chest wall
Absolute Pacemaker indications?
7
- Sick sinus syndrome
- Symptomatic sinus bradycardia
- Tachy-brady syndrome
- Afib with slow ventricular response
- 3rd degree heart block
- Chronotropic incompetence
- -Inability to increase heart rate to match exercise - Prolonged QT syndrome
Pacemakers usually have multiple functions such as? 2
- Sensing (listening) to the heart’s native electrical rhythm
- Pacing the device will stimulate the ventricles of heart with a set amount of energy, measured in joules at whatever heart rate the device is set at
What is pacemaker syndrome?
3
- Patient feels worse after pacemaker placement
- Presents with progressive worsening of CHF symptoms
- Due to loss of atrioventricular synchrony, pathway now reversed and ventricular origin of beat
Biventricular pacing is reserved for therapy for what?
advanced heart failure
The biventricular pacing devices have added a third lead (to position B) that is designed to what?
The combination of all three leads creates a synchronized pumping of the ventricles. How does this help? 2
conduct signals directly into the left ventricle
- Gets rid of the asynchrony between ventricles
- May increase EF
What is ICD therapy?
What controls the different functions of this?
- ICD Therapy consists of pacing, cardioversion, and defibrillation therapies to treat brady and tachy arrhythmias.
- An external programmer is used to monitor and access the device parameters and therapies for each patient.
ICD Indications?
3
- Used in cases where there was a previous cardiac arrest
- Patients with undetermined origin or continued VT or VF despite medical interventions
- Cardiomyopathy (EF
ICDs prevent what?
sudden cardiac death
- What are ICDs designed to treat? (most commonly)
2. What can they also perform?
when?
- Designed to treat cardiac tachyarrythmias
Most commonly in patient’s with cardiomyopathy - Performs cardioversion/defibrillation
If ventricular rate exceeds programmed cut-off rate
- ATP is what?
2. What does it do?
- antitachycardia pacing
2. Overdrive pacing in an attempt to terminate ventricular tachycardias
How long is the lifespan of a pacemaker?
Life span 5 to 10 years
If case of emergency an external defibrillator can still be used. How far away should it be placed from the pulse generator?
10cm
- Left ventricular assist device (LVAD) is for?
- May serve as a bridge for what?
- Pump of the LVAD takes over the work of who?
- Where is the pulse generator for this device?
- severe systolic heart failure
- May serve as a bridge to transplant
- Pump of the LVAD takes over the work of the left ventricle
- Implantable tubes that connect to an external battery pack
Percutaneous coronary intervention: What are the two types?
- Angioplasty
2. Intracoronary stent placement
What are the two types of intracoronary stent placements?
- Bare metal stents
2. Drug coated stents
Whats a major limitation of angioplasty?
Restenosis
Occurs in the first 6 months of 30-40%
Describe a stent implantation.
4
- Before stent implantation, the blocked artery usually is treated and dilated with one or more angioplasty balloons.
- A stent, tightly mounted on a special angioplasty balloon, is then guided to the site of the blockage.
- The angioplasty balloon is inflated to stretch open the stent and implant it into the walls of the blocked artery.
- The balloon is deflated and removed, and the stent remains permanently in place to hold the artery open.
A drug-eluting stent is coated with an agent that inhibits _______.
The Cypher stent is coated with an antibiotic called ______ (also called ________), which is slowly released into the artery for about __ _____ after implantation.
restenosis
sirolimus
rapamycin
30 days
Sirolimus is a “cytostatic” drug, which means what? 2
T-cells initiate an 3._______ _________ that commonly follows implantation, and inflammation can lead to 4.________.
- it inhibits cell growth and division, and
- inhibits T-cell activation and proliferation.
- inflammatory response
- restenosis
With uncoated stents, restenosis occurs in _____% of patients.
The restenosis rate in patients who receive a drug-eluting stent is lower than uncoated stents. By how much?
- These patients require fewer what?
- And a lower risk of what?
15 - 25
(
Factors associated with higher re-stenosis rate:
3
Diabetics
Small luminal diameter (the smaller the blood vessel the easier it is to restenosis)
Longer more complex lesions
Can stents be replaced?
- NO, New stents may be added, but the old stents are not removed.
Additional cardiac stents may be needed if new blockages occur in other parts of an artery.
Angioplasty/Stent Placement Post op what do they need to be on:
- Angioplasty with or without stent placement?
- Angioplasty with stent placement?
- Aspirin for life
2. P2Y12 inhibitor for 12 months or longer in some cases.
Angioplasty/Stent Placement
complications?
7
- Restenosis
- Arrhythmias
- Bleeding at the insertion site
- Heart attack, stroke
- Infection at the insertion site
- Kidney failure (from the IV contrast)
- Ruptured artery (dissection)
What is CABG?
What is it?
CABG – coronary artery bypass graft surgery
A procedure to bypass a blocked section of a coronary artery and to deliver oxygen to the heart
CABG candidates
5
- Failed medical therapy for angina
- Not good candidates for balloon angioplasty and stent placement
- Patients with multiple coronary lesions as is often seen in patients with diabetes
- Left main stenosis
- Patients with significant narrowing of all 3 major arteries, especially in those with systolic dysfunction
CABG Risks and Complications
5
- During and shortly after CABG surgery, heart attacks occur in 5 to 10% of patients and are the main cause of death.
- About 5% of patients require exploration because of bleeding.
- This second surgery increases the risk of chest infection and lung complications.
- Stroke occurs in 1-2%
- Post operative atrial fibrillation is common
CABG Risks and Complications:
Mortality and complications increase with what?
6
- Age (older than 70 years),
- poor heart muscle function,
- disease obstructing the left main,
- diabetes,
- chronic lung disease, and
- chronic kidney failure
What are the most commonly replaced valves?
The aortic valve and the mitral valve are the most commonly replaced valves
The most common valve surgical procedure is _____ ______ replacement for _____ _______ but is also done for what three things?
aortic valve
aortic stenosis
- mitral stenosis,
- aortic and mitral regurgitation, 3. endocarditis
Surgical options for valve replacement
4
- Mechanical valve
- Tissue valve (animal donor tissue) aka bioprosthetic
- Ross Procedure
- TAVI/TAVR procedure (Transcatheter aortic valve replacement)
What is the benefit of mechanical valve replacement?
Downside?
long-lasting valve made of durable materials
Lifelong anticoagulation
Benefit of Tissue valve (animal donor tissue) aka bioprosthetic?
Short term anticoagulation
Some valves can be repaired instead of replaced depending on the disease process. WHich ones are common?
3
There is one that we dont usually repair. why?
- Mitral
- Tricuspid
- Pulmonic
- Short term results
- Risk of stroke
Only do it for palliation of symptoms
