Cardiac Imaging:“Echo”

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Blood moving awayFrom transducer:

Blue

Blood moving towardTransducer:

Red / Orange

Turbulent blood flow:Green

Echocardiogram uses ultrasound reflection and absorption to create chamberimages and doppler technology to determinerate and direction of blood flow

Transducer

Echocardiogram

Stress Echocardiogram

End Diastolic Resting

End Systolic Resting

End Diastolic Max Ex

End Systolic Max Ex

Echocardiogram: Apical 4 Chamber view

Apex of Heart

RV LV

RA LA

TV AVMV

PapillaryMuscle

Apex of Heart

Septum

Tricuspid valve

Aortic valve

Right Atrium

Interatrial Septum

Left Atrium

MitralValve

Apical 4 Chamber View

Transesophageal EchocardiagraphyAdvantages of TEE• Lung air does not attenuate the sound beam• Works better with COPD patients• May be use during surgery• Better visualizes:

• Mitral valve disease• Clots or other masses in the heart• Tears in the aorta• Prosthetic heart valves

Nuclear Stress Test Images

Normal Test

Abnormal Test

Ischemic Areas

Re-perfused after rest

(no permanent

damage from an MI)

Exercise

Rest

Exercise

Rest

Cardiac Catheterization (Angiography)

• Invented by the German physician Werner Forssmann in 1929• Passed a catheter into his own right atrium through the brachial artery

• Performed under local anesthesia & sedation

• Guide wire & catheter inserted into femoral or brachial artery • Advanced into the aorta, left ventricle, and coronary arteries

• Aortic pressure is recorded

• Contrast medium (dye) is injected into coronary arteries• Real-time moving blood flow images are taken with x-ray camera

• Flow through the CA’s appears white against darker background

• Blockages are seen as a narrowing of the white flow

• Contrast medium (dye) is injected into left ventricle• Real-time moving images of LV motion are taken with x-ray camera

• Injected dye appears white against a darker background

• Pressures in the 4 chambers during systole and diastole

• Wall structure and motion

• ESV, EDV, SV, EF

• Heart valve function and pressure gradients across valves

Catheter Entering The LV and LAD Artery

Via The AortaCatheter in femoral artery:• Termed “left heart” catheterization• Aorta, Aortic pressures• CA blockages• Left ventricular function

• LVEDP LVESP• EF• ESV• EDV

Left Heart Catheterization

Catheter in subclavian or neck vein:• Termed “right heart” catheterization• Pulmonary artery pressures

• Pulmonary hypertension• Right atrial pressure• Pulmonary capillary wedge pressure

• Same as left atrial pressure• TC valve assessments

• Pressure gradients, etc.

Right Heart CatheterizationCatheter Entering The RA, RV, and Pulmonary Artery via the Superior

Vena Cava

Cardiac Catheterization Lab As Viewed Through The Control Room

Need for emergency CABG during PTCA:

1992: 1.5%

2000: .014%

LAD Catheterization Video

Ventriculogram (LV function)

Courtesy: J. Wade Womack

            

Cath Images

LAD blockage

RCA blockage

Cath Images

Left InternalCarotid Artery

Left ExternalCarotid Artery

Left CommonCarotid Artery

Blockage

• Risks and Possible Complications• Bleeding around the point of incision

• Abnormal heartbeats (arrhythmias)

• Allergic reaction to the dye

• Infection

• Blood clots (stroke or pulmonary embolism)

• Perforation or other damage to the arteries

• Heart attack

• Stroke

• Air embolism

• Death (Mortality about .08%)

Cardiac Catheterization (Angiography)

PTCA: Percutaneous Transluminal Coronary Angioplasty

• Currently used as primary intervention for Acute Coronary Syndrome (MI)

• Local anesthesia and sedation

• Catheter with balloon placed at the end is advanced into blocked artery

• Balloon is inflated, pressing plaque against artery walls

• Arterial lumen is increased facilitating better blood flow.

• Stent is often placed to act as scaffold to hold artery open

• Stents: metal mesh sleeves that “prop” artery open

• Stents are sometimes coated with drugs that inhibit re-stenosis

• The site of the stent placement may receive a dose of radiation

• Called “brachytherapy”

• Prevents cell overgrowth in area of stent placement

• Glycoprotein IIb/IIIa inhibitors may be used to prevent clots during placement

• Plavix and aspirin are usually used to help prevent clots post-surgery

• Results are usually only temporary: 18% - 40% chance of re-stenosis

• Blockage almost always requires further treatment (PTCA or CABG)

Angioplasty

Angioplasty is the most common & effective treatment for acute MI

• Better results than thrombolytic (fibrinolytic) therapy (ThT)

• The use of Streptokinase, TPA, other agents to dissolve occlusion

• PTCA may be used in combination with ThT

• Stabilize patient, give ThT, PTCA done 12 to 48 hr afterwards

• PTCA has d mortality rate, fewer re-infarctions, fewer strokes

• ThT should be done < 12 hours after symptoms

• PTCA should be done < 2 hours after arrival at hospital

• Benefits from both ThT and PTCA decline after time “windows”

• Bottom Line…the earlier the better for both interventions

• Use of stents for acute MI angioplasty seems to improve outcomes

• Stents associated with a 19% d in re-infarction or repeat PTCA’s

Angioplasty vs. Throbolytic Therapy

Mortality rate for PTCA vs Thrombolytic Therapy in Acute MI

0

2

4

6

8

10

12

14

Pami Zwollee Mayo Gusto Miti CCP Weaver

Thlytic

PTCA

N: 395 395 103 1138 3145 20,683 2606

% M

orta

lity

0

5

10

15

20

25

30

Stent

PTCA only

Mortality Reocclusion Emergency CABG

Revascularization of same vessel

Non-fatal MI

Any Event

Per

cen

t

Outcomes for PTCA with Stent vs. PTCA only

Coronary Stents

Blade Atherectomy

Rotary Atherectomy

Laser Atherectomy

Stent Placement

Courtesy: J. Wade Womack

After Stent Placement

Before Stent Placement

Coronary Artery Bypass Graft Surgery (CABG)

• First “modern day technique” CABG performed in 1962 by Sabiston

• World most expensive “Plumbing Job”

• Approximately $45,000 (Sollano 2002)

• General anesthesia, patients chest opened, sternum sawed, ribs spread

• Patient is placed on a respirator (ventilation machine or ventilator)

• Patients heart is stopped by perfusing the heart with potassium

• Person is placed on heart lung apparatus

• Device circulates and oxygenates blood while heart is stopped

• Cooling the heart – d need for O2:

• Blood be cooled while passing through heart-lung machine

• Cold saline may be poured over the heart during surgery

• Grafts harvested: saphenous veins, mammarian artery

• Grafts sutured from aorta to CA, “bypassing” the blockage

• Takes 3 – 6 hours

• After surgery, patient is taken to ICU (CCU) where he is weaned off ventilator

• IV’s and drainage tubes removed over the next 48 hours (longer in older people)

• Patients eating on their own after 24 hours and rehab is begun within 48 hours

• Patients with no complications go home after about 4 days

• Patients back to full strength within 6 weeks - no driving or working for 6 weeks

Mammarian Artery

Bypass Graft

SaphenousVein

harvested from leg

Blockage

SaphenousVein

Bypass Graft

Heart

Aorta

Venous

Blood (to machine)

Arterial Blood

(from machine)

Modern Heart – Lung Machine

First Heart – Lung Machine: developed in 1953 and used in the surgical closure an atrial defect in an 18 year old girl

                                             

Rib Spreader Reveals Heart Graft be anastamosed (sutured) to CA

CABG Surgery

• Risks and Possible Complications• Risks associated with anesthesia

• respiratory failure

• Bleeding

• Abnormal heartbeats (arrhythmias A-fib / A-flutter is common)

• may need pacemaker

• Infection at incision sites

• Blood clots and plaque (stroke or PE, blocking of O2 to tissues)

• Memory loss and problems with cognitive function

• Heart attack

• Pneumonia

• Hypotension from being on heart-lung machine r Kidney failure

• Heart failure

• Swelling of ankles or feet on the leg where graft was removed

• Depression, anxiety and other emotional difficulties

• “Post Pump Syndrome”:

• systemic inflamation in lungs r edema, kidneys r kidney failure

• Death (Mortality about 1.5%…..15% for “redo’s”)

Coronary Artery Bypass Graft Surgery (CABG)

• CABG is usually not the first consideration for treatment• not done unless the risks of not having the procedure are high

• 50% of grafts develop lesions within 10 years• Rate may be reduced by statin drugs

• 516,000 CABG surgeries done every year• Routine surgery today

• Very high success rate (97%- 99%)• 67% of patients report NO COMPLICATIONS

Notes on CABG surgery

Recent Developments In Cardiac Surgery

• Off-Pump Coronary Artery Bypass (OPCAB)

• Same as regular CABG but with no heart lung machine

• Drugs such as Adenosine and Esmolol are used to slow HR

• Could be performed 30% - 40% of the time when CABG surgery is needed

• Minimally Invasive Direct Coronary Artery Bypass (MIDCAB)

• Smaller transverse incision

• No sternotomy, done on beating heart (drugs used to slow HR)

• Use of radial artery for grafts (grafts last longer)

• Gene therapy (inhibits hyperplasia of intimal cells)

• Transmyocardial Laser Revascularization (TMLR)

• Lasing holes directly into myocardium to u myocardial blood supply

• Based on reptile heart which has no CA’s

• Stem cells injected into myocardium of CHF patients

• Increase myocardial tissue or form new vasculature?

• Stem cells injected into CA’s during revascularization

• Mixed results – some arteries re-stenosed at a higher rate