Diagnostic Tests Performed at Physician Offices

Nuclear Cardiology
Nuclear cardiology studies use techniques to assess blood flow to the heart muscle, evaluate the pumping function of the heart as well as to visualize the size and location of heart muscle damage due to blockages in coronary arteries. Among the techniques of nuclear cardiology, myocardial perfusion imaging (examination of blood flow to the heart muscle) is the most widely used.

Myocardial Perfusion images are combined with exercise to assess the blood flow to the heart muscle. Exercise is in the form of walking on a treadmill. In the event that a person cannot exercise on the treadmill, a chemical stress test using the drug dipyridamole, adenosine, or dobutamine is performed.

A small amount of imaging agent (Cardiolite or Myoview) is injected into the blood stream through a vein in the arm during rest and during exercise or chemical stress. A scanning device (gamma camera) is used to measure the uptake by the heart of the imaging material during (exercise or chemical stress) and at rest. If there is significant blockage of a coronary artery, the heart muscle may not get enough of a blood supply in the setting of exercise or during chemical stress. This decrease in blood flow will be detected by the images.

Myocardial perfusion studies can thus identify areas of the heart muscle that have an inadequate blood supply as well as the areas of heart muscle that are scarred from a heart attack. In addition to detecting blockage of a coronary artery, myocardial perfusion studies quantify the extent of heart muscle with limited blood flow and provide information about the pumping function of the heart. Thus it is superior to routine exercise stress testing and provides the necessary information to help identify which patients are at an increased risk for a heart attack and may be candidates for invasive procedures such as cardiac catheterization, angioplasty, or heart surgery.

Nuclear cardiology studies also evaluate heart muscle function meaning the examination of how well the heart muscle pumps. Functional studies (Radionuclide Ventrioulography) include Radionuclide Angiocardiography (RNA), Multiple Gated Acquisition (MUGA), and Gated Single Photon Emission Computer Tomography (GSPECT). In patients with coronary artery disease and in those who have had a heart attack, the assessment of the pumping function of the heart (also known as the ejection fraction) is essential in the prediction of both long term and short-term survival. A small dose of an imaging agent is injected into the blood steam and pictures of the four chambers of the heart are taken using a special camera (gamma camera). These techniques can also provide information about the function of the valves of the heart, the integrity of all the cardiac chambers and can be used to monitor the effect of different drugs on the heart muscle (in patients with cancer who are treated with chemotherapy.

Patient Instructions Prior to Nuclear Cardiology Studies:

1. Wear comfortable clothing and footwear. Men: slacks, shorts, jogging suit, etc. Women: slacks, shorts, skirt with half-slip Footwear: tennis shoes or flats with non-slip sole
2. For Dr. Phelan: you may eat your usual breakfast including caffeine. For all other physicians: do not eat or drink anything after midnight the night before. Diabetics may take half of their dose of insulin in the morning before coming for the test.
3. Take your routine medications the day of the test unless specifically told otherwise.
4. The nuclear stress test is in two parts, but will last off and on all day.
5. The doctor or a nurse from our office will call you to discuss the results when they are completed and available.
6. Our lab orders the myoview from a local pharmacy the afternoon before your test, and they will not allow us to return unused dosages. If you determine that you will not be able to keep your appointment, our office must receive 24 hours advance notice of your cancellation, or this cost may be passed on to you.
7. Please call our office with any questions or problems.

Treadmill Stress Test
The patient is asked to walk on a treadmill during which time the electrical impulses in the heart are recorded. Patches with wires are applied to the chest and connected to an ECG monitor during the test. Please wear comfortable clothing and footwear.

Echocardiogram
An echocardiogram uses sound waves to produce images of the heart as it is beating. This enables the physician to evaluate heart valves, the strength and thickness of the heart muscle, and the size of the chambers of the heart. There are no special preparations or instructions for the study.

Stress Echocardiogram
Stress echocardiogram combines a treadmill stress test with an echocardiogram to produce images following exercise. Please wear comfortable clothing and footwear.

Cardiac Doppler
The cardiac Doppler reveals the speed and direction of blood flow within the heart. Cardiac Doppler is helpful in evaluating valve function. The Doppler uses sound waves which reflect off the moving red blood cells within the heart chambers. It is usually performed with the 2 Dimensional Echocardiogram. Color flow mapping is usually done in conjunction with Doppler test. It shows speed and direction of blood flow, and the images are in color. The color allows the physician to map abnormalities in blood flow. There are no special preparations or instructions for the study.

Carotid Ultrasound
Carotid ultrasound uses sound waves to obtain color images of the arteries in the neck. The physician evaluates the images to determine to what extent these arteries are blocked and how much blood is flowing to the brain and eyes. There are two carotid arteries, one on each side of the neck. Both sides are checked during the procedure. There are no special preparations or instructions for the study.

Holter Monitoring
Holter monitoring is a diagnostic tool to record heart rhythm and rate information that is later analyzed for arrhythmias and other abnormalities. The holter monitor measures and record electrical impulses in the heart. Patches with wires are applied to the chest and connected to a portable monitor that can be attached to a belt or purse. There are no special preparations or instructions for the study.

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Cardiac Catheterization
A cardiac catheterization is a special X-ray study of the heart to diagnose coronary artery disease. Coronary artery disease refers to any abnormal condition of the arteries in the heart that interferes with the delivery of an adequate supply of blood to the heart muscle. More than 95% of all coronary artery disease is atherosclerosis, a build up of fatty substance (plaque) inside the artery walls.

When the heart muscle does not get enough oxygen rich blood to meet the demand, the heart muscle experiences a hunger for more oxygen, and the patient experiences angina. Symptoms of angina include chest pressure, tightness, heaviness and discomfort in the arm, jaw, back, or neck. In order to effectively treat coronary artery disease, we must have an accurate picture of the coronary arteries. The only way we can actually see the coronary arteries is by injecting dye into them during cardiac catheterization.

Cardiac catheterization is also useful in diagnosing other kinds of heart trouble such as defective heart valves, muscle disease and problems of the heart from birth known as congenital abnormalities. During cardiac catheterization, your major blood vessels may also be evaluated to look for problems with blood flow.

Cardiac Catheterization is performed in a cardiac cath lab in the hospital. During cardiac catheterization, your cardiologist inserts a long, thin tube into a blood vessel in the upper leg (groin) or arm. The tube is gently directed to the heart and to the origin of the coronary arteries. Dye is then injected into the coronary artery while X-ray pictures are taken. The dye in the coronary arteries is seen by X-ray as a white line. A disruption in the white line may signify an area of plaque buildup inside the wall of the artery.

During the same procedure, dye may be injected into the heart's pumping chambers in order to see how well the heart muscle is contracting and how well the valves are working. Pressure measurements are also taken at this time and are interpreted by a computer.

Coronary Angioplasty
If a cardiac catheterization reveals a blockage or restriction in blood flow in a coronary artery, your cardiologist may recommend coronary angioplasty (PTCA) to improve blood flow.

P - percutaneous; meaning access to the blood vessel is made through the skin
T - transluminal; meaning the procedure is performed within the blood vessel
C - coronary; identifying that the coronary artery is being treated
A - angioplasty; meaning "to remodel" the interior of the blood vessel with balloon inflation

Your cardiologist performs balloon angioplasty during a cardiac catheterization by advancing a small tube with a balloon into the narrowed coronary artery and inflating the balloon to open the blockage in the coronary artery.

Your cardiologist may decide to place a stent after performing balloon angioplasty. Stent placement is performed to keep the artery open following balloon angioplasty. A stent is a metallic scaffold placed over a delivery balloon catheter that is positioned in the narrowed site of the artery. The stent is implanted in the artery wall by inflating the stent delivery balloon. The stent delivery balloon catheter is then removed, and the stent remains to hold the artery open.

Beta-Cath(TM) System
The Beta-Cath(TM) System is a device designed to deliver a low dose of Beta radiation to the site of an angioplasty or stent placement to prevent re-narrowing. Beta radiation treatment is intended to discourage the overgrowth of normal tissue as the healing process occurs following angioplasty or after stent placement. Overgrowth of normal tissue is thought to be a major factor responsible for re-narrowing of the artery after angioplasty or stent placement.

A Beta-Cath procedure is performed in the cardiac catheterization lab following an angioplasty to open a blockage within a coronary artery. The Beta-Cath catheter is positioned in the artery after the balloon catheter is removed. The Beta-Cath catheter allows delivery of Beta radiation sources to the site of the blockage and treatment of the area for a precise amount of time, usually 2 to 5 minutes. The size of the artery helps determine the treatment time. When the Beta radiation treatment is completed, the radiation sources and catheter are removed. No radiation remains in the body.

With the Beta-Cath(TM) System, the dose of radiation is localized to the treatment site in the coronary artery and the risk of complications is thought to be low. The dose of radiation to the body is minimal - less than a chest x-ray and much less than that received during a heart catheterization.

NOGA
The NOGA Cardiac Navigation System uses active magnetic fields generated from underneath the X-ray table in the Cardiac Cath lab along with a passive sensor from within the catheter tip to create three-dimensional cardiac maps. As the NOGA catheter is maneuvered within the left ventricle of the heart, its movement and location are tracked. The sensors provide data to a computer that calculates the precise location of the catheter tip relative to a fixed point on the patient. The computer than generates maps showing the electrical and mechanical characteristics of the inside surface of the heart. The NOGA system provides advanced diagnostic information regarding electromechanical function of the heart and assists your cardiologist in defining strategies to improve circulation.

Pacemaker Implantation
The heart is composed of four chambers enclosed within a wall of muscle. The upper two chambers (atria) will help fill the lower two chambers (ventricles) with blood. The ventricles are larger and more heavily muscled than the atria. They pump blood to the lungs and throughout the rest of the body.

The heart's natural pacemaker, located in the upper part of the heart, normally regulates your heart rate. This natural pacemaker, called the sino-atrial node (S-A node), is a small cluster of specialized cells that produce electrical signals at regular intervals. The S-A node automatically increases your heart rate in response to your body's needs - for example, during exercise, when a faster blood flow is required.

The electrical impulses sent out by the S-A node travel to the atrioventricular node (A-V node), a second cluster of cells located near the center of the heart. The A-V node then transmits the electrical signals out to the walls of the ventricles.

This natural electrical pathway is very important because when the signals reach the lower heart, both ventricles contract, pumping blood throughout the body. Any problem with this natural electrical pathway may cause a change in heart rate and/or rhythm and effect circulation of blood from the heart to the rest of the body. Sometimes the heart is not able to keep up with the body's need for blood, and your cardiologist may recommend pacemaker implantation.

A pacemaker alters the heart rate to help meet your body's needs. It does this by providing pacing signals that are much like the heart's normal signals. Depending the particular situation, a pacemaker may:

• Replace S-A node signals that are delayed or get lost along the pathway between the upper and lower heart
• Help maintain a normal timing sequence between the upper and lower heart
• Make sure the critical lower chambers of the heart always contract at an adequate rate

Every pacemaker system has two parts; the pulse generator, which produces the pacing impulses and the lead or leads which deliver these impulses to the heart. The same leads also carry signals back from the heart. By "reading" these signals, the pulse generator is able to monitor the heart's activity and respond appropriately.

The pulse generator is usually implanted below the collarbone just beneath the skin. The leads are threaded into the heart through a vein located near the collarbone; the tip of each lead is then positioned inside the heart. However, sometimes the pulse generator is positioned in the abdomen and the pacemaker leads are attached to the outside of the heart. The decision, where and how to implant the pacemaker system, is made by your cardiologist based on individual needs.

Following implantation, periodic pacemaker evaluations are scheduled to monitor pacemaker function. Evaluations will include office visits as well monitoring by telephone. The object of these assessments is to check to see if your pacemaker is working properly. Your cardiologist determines the frequency of pacemaker evaluations. During office visits your cardiologist may analyze pacemaker function using a computer and adjust programmable functions to help the pacemaker work better and to preserve battery life. Monitoring by the telephone allows you to have your pacemaker checked in the comfort of your home using a specialized telephone transmitter which relays important information regarding your pacemaker function to your cardiologist's office.

Automatic Implantable Cardioverter Defibrillator (AICD) Implantation
The heart is composed of four chambers enclosed within a wall of muscle. The upper two chambers (atria) will help fill the lower two chambers (ventricles) with blood. The ventricles are larger and more heavily muscled than the atria. They pump blood to the lungs and throughout the rest of the body.

The heart's natural pacemaker, located in the upper part of the heart, normally regulates your heart rate. This natural pacemaker, called the sino-atrial node (S-A node), is a small cluster of specialized cells that produce electrical signals at regular intervals. The S-A node automatically increases your heart rate in response to your body's needs - for example, during exercise, when a faster blood flow is required.

The electrical impulses sent out by the S-A node travel to the atrioventricular node (A-V node), a second cluster of cells located near the center of the heart. The A-V node then transmits the electrical signals out to the walls of the ventricles.

This natural electrical pathway is very important because when the signals reach the lower heart, both ventricles contract, pumping blood throughout the body. Sometimes things go wrong in the heart's electrical system. The heartbeat becomes irregular or changes its rate. This is called an arrhythmia. Dangerous arrhythmias may prevent the heart from pumping enough blood throughout the body, and your cardiologist may recommend implantation of an AICD.

Every AICD system has two parts; the pulse generator and the lead or leads. The pulse generator checks your heart's electrical signals and delivers electrical therapy when it senses a dangerous heart rhythm. The lead or leads connect the pulse generator to the heart. Based on settings programmed by your cardiologist, the AICD system watches your heart all the time. It waits for an arrhythmia to happen. If one is sensed, the AICD determines what type of electrical treatment, if any, you need. Then, it delivers the electrical treatment to return your heart rate to normal.

The AICD is usually implanted below the collarbone just beneath the skin. The leads are threaded into the heart through a vein located near the collarbone; the tip of each lead is then positioned inside the heart. However, sometimes the pulse generator is positioned in the abdomen and the pacemaker leads are attached to the outside of the heart. The decision, where and how to implant the pacemaker system, is made by your cardiologist based on individual needs.

Following implantation, your cardiologist will tell you when to call him and what to do if you experience an electrical treatment from your AICD. Periodic evaluations will be scheduled to monitor AICD function. During these visits your cardiologist will analyze your AICD using a programmer computer. Programmers are used to communicate with the AICD pulse generator for programming treatment and retrieving treatment history.

Electrophysiology (EP) Study / Catheter Ablation
The heart is composed of four chambers enclosed within a wall of muscle. The upper two chambers (atria) will help fill the lower two chambers (ventricles) with blood. The ventricles are larger and more heavily muscled than the atria. They pump blood to the lungs and throughout the rest of the body.

The heart's natural pacemaker, located in the upper part of the heart, normally regulates your heart rate. This natural pacemaker, called the sino-atrial node (S-A node), is a small cluster of specialized cells that produce electrical signals at regular intervals. The S-A node automatically increases your heart rate in response to your body's needs - for example, during exercise, when a faster blood flow is required.

The electrical impulses sent out by the S-A node travel to the atrioventricular node (A-V node), a second cluster of cells located near the center of the heart. The A-V node then transmits the electrical signals out to the walls of the ventricles.

This natural electrical pathway is very important because when the signals reach the lower heart, both ventricles contract, pumping blood throughout the body. Any problem with this natural electrical pathway may cause a change in heart rate and/or rhythm and effect circulation of blood from the heart to the rest of the body. An abnormal rhythm (arrhythmia) is a change in either the speed or pattern of the heartbeat. An arrhythmia becomes serious when the heart beats too slowly or too rapidly to pump blood effectively, or when there is a threat to the person's life.

When basic diagnostic tests do not provide all of the necessary information to properly diagnose or locate an arrhythmia, an electrophysiology (EP) study may be recommended by your cardiologist.

An EP study is performed in an EP lab in the Cardiac Cath Lab in the hospital. During an EP study, your electrophysiologist inserts a long, thin tube into a blood vessel in the upper leg (groin) or arm. The tube is gently directed to the heart. The special electrode catheters used for the procedure are long and flexible wires that can conduct electrical impulses to and from the heart. One or more catheters are inserted into the body and advanced toward the heart, while the staff follows their progress on a television screen. The catheters are then positioned inside the heart.

The EP study is done to diagnose or locate your heart rhythm problem. Basically, the EP study is performed by doing two things:

1. Recording Electrical Signals: Electrode catheters sense electrical activity in various areas of the heart and measure how fast electrical impulses travel.
2. Pacing the Heart: Electrode catheters can also be used to deliver tiny electrical impulses to pace the heart. By doing so, doctors try to induce (bring on) certain abnormal heart rhythms, so that they can be observed under controlled conditions.

If an arrhythmia is induced, medications may be given through the IV line to test their effect on the heart rhythm.

Catheter Ablation
An EP study helps determine the location of the heart's abnormal electrical activity causing arrhythmia. The location and type of heart rhythm problem will determine whether catheter ablation is a treatment option.

During catheter ablation, your electrophysiologist inserts an ablation electrode catheter into the heart. He positions the catheter so that it lies close to the abnormal electrical pathway that is causing the arrhythmia, then he passes radio-frequency energy through the electrode catheter.

The tip of the catheter heats up and destroys the small area of heart tissue that contains the abnormal pathway. This produces scar tissue which is unable to transmit electrical impulses. As a result, the abnormal electrical pathway is no longer capable of producing arrhythmias.

Instructions for Patients Having Procedures performed in a Cardiac Cath Lab Within a Hospital
1. Be sure to bring all regularly taken medicines (including insulin) in their original bottles. Your doctor may want to continue your regular medication schedule even while you recover from your procedure.

You should check with your doctor or nurse concerning any medicines you presently take on a regular basis, especially if you are on a "water pill," diuretic, insulin, glucophage, or a blood thinner other than aspirin. For patients undergoing an Electrophysiology (EP Study) procedure, certain rhythm medicines may need to be stopped several days before the procedure.

Check with your doctor or nurse to find out which medication to take prior to your procedure.

Make sure your doctor and nurse are aware of your allergies.

2. Do not eat or drink anything after midnight before your procedure unless otherwise instructed by your doctor or nurse.

3. If you are having a same day outpatient procedure, make arrangements for a friend or family member to bring you to the hospital and to drive your home. Please plan to spend the day at the hospital on the day of your procedure.

It is preferred that someone stays with your while you are at the hospital and stays with you at your home during the night after your procedure.

4. Please bring insurance cards when you come to the hospital for your procedure.

5. Please bring your bathrobe and slippers. You will need these in the outpatient area. Pack a small overnight bag in case you need to stay overnight.

6. Leave all jewelry and valuables at home. Remove all fingernail and toenail polish.

7. If you wear contact lens, pack your contact lens solution and container. Please bring your glasses, dentures, and hearing aids. You will be allowed to wear them during your procedure.

8. Be sure that you know what time you should arrive at the hospital and where you should go once in the hospital.

9. Call your doctor or nurse if you have any questions.

10. Please do not bring small children with you to wait during your procedure.