Cardiac interventions Flashcards
Coronary catheter
An invasive catheter-based procedure that gives detailed hemodynamic and anatomic information about the heart and the coronary arteries.
Left heart catheter
- catheter is inserted into radial* or femoral artery
- Flexible sheath inserted into the vessel over a
guidewire - Diagnostic catheter then advances under
fluoroscopic guidance into left ventricle
à Get direct measurement of LV
pressure, hemodynamics (AS, HCM)
Coronary angiography
An invasive catheter-based procedure
that uses radiopaque contrast dye to
define the coronary anatomy and help
determine extent of coronary disease
Coronary Cath and Coronary angiography indications
1) evaluate severity of cardiac disease in symptomatic pts and
2) determine if medical, surgical or catheter-based interventions are warranted
Relative contraindications for cardiac cath:
- decompensated diastolic HF
- Acute renal failure
- Chronic renal failure (unless dialysis is planned)
- Bacteremia
- Acute stroke
- active GI bleeding
- Anticoagulation or recent thrombolytics
- severe, uncorrected electrolyte abnormalities
- contrast allergy, aspirin allergy
Cardiac cath risks
- Risks are low:
<0.1% MI, 0.01% for stroke, 0.05% for
death - In-hospital mortality is 1.4% -
increased if done emergently during
AMI, hemodynamically unstable - Other risks: arrhythmias, acute renal
failure (dye or poor perfusion),
contrast allergy dye allergic reaction,
vascular complications/perforation,
Most common complications =
access site bleeding, 1.5-2.0%
Cardiac cath post procedure guidelines
- Bed rest ~2h, can often be discharged same day
- Observe high-risk patients overnight
- Pressure dressing on access site
- Monitor for hypotension
- Increased fluid intake (contrast à osmostic diuresis)
Percutaneous coronary intervention - what is it?
Invasive catheter-based interventions on
a plaque or stenosis in the coronary
arteries.
- Balloon Angioplasty
- Stent Angioplasty
- Atherectomy
- Thrombectomy
PCI - indications
ACS/STEMI
NSTEMI
UNSTABLE ANGINA
STABLE ANGINA
ANGINAL EQUIVALENT
HIGH-RISK STRESS TEST FINDINGS
CRITICAL CORONARY ARTERY STENOSIS
THAT DOES NOT QUALIFY FOR CABG
PCI - risks and complications
- DISSECTION OR RUPTURE
(CORONARY OR AORTA) - BLEEDING (ACCESS SITE MOST
COMMON) - INFECTION
- RENAL FAILURE
- STROKE
- MI
When is CABG preferred over PCI?
2 or 3-vessel disease + high SYNTAX score
left main disease pts with DM and multivessel disease
When is PCI preferred over CABG?
severe symptoms
failed medical therapy
High-risk coronary anatomy
Worsening LV function
CABG - What is it?
Coronary artery bypass graft: Revascularization procedure using a grafted
vessel to go around the stenotic/diseased
coronary
Vessels commonly used for bypass grafting
1) Left internal mammary artery (LIMA)
2) Saphenous vein graft (SVG) harvested
from either leg.
3) Right internal mammary artery (RIMA)
4) Radial artery from either arm
Usual “Life” of a bypass:
1) LIMA, RIMA, radial artery - 10-12 years
2) SVG - 7-10 years
CABG - Indications
● Left main coronary artery stenosis >50%
● 3-vessel disease >70% with/without proximal LAD involvement
● 2-vessel disease: LAD + one other major artery
● Patients with significant anginal symptoms despite adequate medical
therapy and 1+ significant stenosis >70%
● 1-vessel disease >70% in a survivor of sudden cardiac death, with ischemia
related V-tac
CABG contraindications
- Patient refusal
- High Mortality Risk/Not a surgical
candidate - Coronary arteries incompatible with
grafting - No viable myocardium to graft
- <70% blockage, single lesion (left
circumflex or right coronary)
Clinical significance of a CABG
Appropriately selected patients have
improved outcomes and increased
survival benefits compared to PCI or
medical therapy alone
STEMI stands for vs. NSTEMI
ST Elevation myocardial infarction
Non - ST Elevation myocardial infarction
CABG - Risks and Complications
- Post-op arrythmias - 20-50%
- Death: 1-2% and varies according to co-
morbidities, urgency of surgery, case-
volume - Graft failure: SVG most common w/in 1st
month can be up to 25%; 1st year (10-
20%), 5th year (~2%).
1) LIMA has better success, 90%
patency rates at 10 years
Right heart catheterization - what is it?
A catheter-based procedure used to determine
right heart and pulmonary artery pressures
Under fluoroscopic guidance, a catheter is
floated sequentially through the right atrium,
right ventricle, pulmonary artery, and into the
pulmonary wedge position (as a surrogate
for left atrial pressure)
Indications for Right heart catheterization
OLD STANDARD TEST to establish PH
diagnosis and choice of treatments
unexplained dyspnea, pulmonary hypertension,
valvular heart disease, pericardial disease, right
and/or left ventricular dysfunction, congenital
heart disease, and suspected intracardiac
shunts
Electrophysiology Studies (EPS) - What is it?
To assess, detect, and/or discover the origin of an arrhythmia. Often
used to assess success of current pharmacologic therapy
Indications for EPS studies
Arrhythmia: Bradycardia, sick sinus, high-grade AV blocks, a-fib, v-
fib, v-tach, re-entry tachycardias; preparatory to pacemaker and/or
defibrillator placement
Contraindications for EPS studies
Severity of underlying comorbid conditions (ie heart failure)
Acute comorbidity (ie pericardial effusion or tamponade)
Arrhythmias from reversible causes
Active thrombus within the heart chambers
EP study results would not change therap
EPS study risks
Clots, infections, dissection, puncture, stroke, heart attack, death,
arrhythmias incite
Ablations - what is it?
Catheter-based or surgical procedure using RF or cryoablation to isolate ectopic foci
that trigger arrhythmias. Catheter is placed percutaneously through femoral vein,
threaded up into right atria, trans-atrial approach (puncture the atrial septum) to
reach the left atrial regions of the pulmonary vein antra
Ablations indications
Atrial fibrillation or other supraventricular/atrial tachycardias,
Ventricular arrhythmias
Clinical significance/Results of ablations
Can reduce or eliminate need for antiarrhythmic drugs
Paroxysmal AF: in 70% of pt, sinus rhythm maintained >1 year with a single ablation
After multiple ablations this can be >90%
Persistent or long-standing AF: ablations does not offer same success rate
Defibrillators
used to addressed ventricular arrhythmias by detecting serious rhythms and then delivering a shock to the heart
Most devices have 3-levels of therapy: anti-tachycardia pacing, low voltage shock – cardioversion or high-voltage shock – defibrillation
Defibrillators Contraindications
Reversible ventricular arrhythmias
VT/VF amenable to ablation
Incessant VT/VF
Expected 1-year survival rate is low from other comorbidities
Significant psychiatric or behavioral issues
Refractory NYHA IV symptoms
Active infection (e.g. sepsis, bacteremia, cellulitis)
Patient refusal or other directives
Pacers - What is it?
Pacemaker – used to support (or replace) the cardiac conduction system (SA node)
Indications for pacers
Sick sinus syndrome
● Symptomatic sinus bradycardia
● Tachycardia-bradycardia syndrome
● Atrial fibrillation with sinus node dysfunction
● Complete atrioventricular block (third-degree block)
● Chronotropic incompetence (inability to increase the heart rate to
match a level of exercise)
● Prolonged QT syndrome
● Cardiac resynchronization therapy (advanced HF)
Class 1 indications for defibrillators
Cardiac arrest survivors – when the etiology is unstable, sustained VT
Structural heart disease with spontaneous sustained VT (regardless of hemodynamic stability)
Unexplained syncope with hemodynamically significant sustained VT/VF induced during EPS
Ischemic cardiomyopathy – LVEF <35% from MI (min 40 days out with NYHA Class II-III)
Non-ischemic cardiomyopathy – LVEF <35% with NYHA Class II-III
LV dysfunction due to MI
Non-sustained VT due to MI – LVEF <40% + sustained VT/VF during EPS
Contraindications of defibrillators
Reversible ventricular arrhythmias
VT/VF amenable to ablation
Incessant VT/VF
Expected 1-year survival rate is low from other comorbidities
Significant psychiatric or behavioral issues
Refractory NYHA IV symptoms
Active infection (e.g. sepsis, bacteremia, cellulitis)
Patient refusal or other directives
Risks to implantable devices: pacers and defibrillators
Pocket/site infection
Allergic reaction to procedural medications
Bleeding/bruising at site
Venous damage à upper extremity DVT
Cardiac tamponade
Pneumothorax
Damage to device wires
Valve repair/replacement - what is it?
Surgical or catheter-based procedure that addresses valvular pathology either
through repair or replacement with bio-prosthetic or mechanical valves
Indications for valve repair/replacement
Severe stenosis, regurgitation, functional compromise or the beginnings of
compensatory anatomical changes related to any particular valve (but usually
related to the aortic or mitral valve, ie left ventricular hypertrophy/dilation, aortic root
enlargement, left atrial dilatation)
Contraindications of valve repair/replacement
Poor surgical candidacy/high surgical mortality risk.
1 year survival is low from other comorbidities.
Senility/dementia.
Valve anatomy not conducive to repair.
Intolerance or inability to take anticoagulation.
Active infection, especially endocarditis.
Asymptomatic valve pathology
Ventricular assist device - what is it?
An implantable device that replaces/supports the systolic function of the LV; bridge to transplant or destination therapy for non-transplant candidates
Indications for a ventricular assist device
- Severe cardiomyopathy from any number of etiologies: nonischemic cardiomyopathies, ischemic cardiomyopathy, complex congenital heart disease, re-transplant, etc.
- Continuous IV inotropic or circulatory (ECMO, IABP, LVAD, etc.) support.
- Persistent, refractory NYHA Class IV heart failure, refractory to medical and surgical therapies
- Intractable or severe anginal symptoms without reasonably treatable targets
- Intractable life-threatening arrhythmias (that are unresponsive to medical, surgical, ablative, or ICD devices, etc.
Heart transplant indications
Severe cardiomyopathy from any number of etiologies
Continuous IV inotropic or circulatory (ECMO, IABP, LVAD, etc.) support.
Persistent NYHA Class IV heart failure, refractory to medical and surgical therapies
A few more, usually includes low VO2 thresholds
Intractable or severe anginal symptoms without reasonably treatable targets
Intractable, refractory life-threatening arrhythmias
