A holter monitor is essentially a 24 hour ECG.  Some of the main reasons a holter monitor is used is to help diagnose the underlying cause for patients experiencing palpitations, dizziness/lightheadedness,  and fainting or near fainting spells.  The monitor is hooked up in office and afterwards, the patient cannot shower or take it off till the following day.  While wearing the monitor it is best to do normal daily routine so the most accurate results can be obtained.  The patient will be asked to keep a diary of their symptoms and activities over the 24 hour time period.

The purpose of an upper extremity arterial evaluation is to detect the presence, severity and location of narrowing of the arteries caused by plaque or cholesterol buildup .  Some of the indications for an upper extremity arterial evaluation include:

  • Asymmetrical brachial systolic blood pressure readings
  • Suspected upper extremity arterial embolism
  • Reduced pulses
  • Evaluation of arterial trauma
  • Numbness or tingling in the arms or hands

A transcranial ultrasound is used to measure the velocity of blood flow through the brain's blood vessels.  It is used to help in the diagnosis of blood clots, narrowing of the arteries, aneurysm, and other problems.  Because the bones of the skull block the transmission of ultrasound, regions with thinner walls must be used for analyzing. For this reason, recording is performed in the temporal region above the cheekbone, through the eyes, below the jaw, and from the back of the head. Patient age, gender, race and other factors affect bone thickness, making some examinations more difficult or even impossible. Most can still be performed to obtain acceptable responses, sometimes requiring using alternate sites from which to view the vessels.

This test is used to evaluate blood circulation in the major arteries.  Blood pressure measurements at various locations in the arms and legs. By detecting differences in blood pressure at specific locations in different limbs, this test helps to diagnose arterial blockages and other circulation problems. It is most commonly performed in people suspected of having peripheral arterial disease (PAD), a narrowing of arteries in the legs due to the accumulation of plaques.  It is the most useful initial test to identify PAD.  Sometimes the patient is asked to walk on a treadmill to help aid in diagnosis.


Purpose of the segmental limb pressures:

  • To evaluate arterial blood flow in the arms or legs and detect blockages, trauma, or other circulation problems
  • To aid in the diagnosis of PAD, determine the location and extent of any arterial blockages, and (with the treadmill test) determine the severity of functional impairment due to PAD
  • To monitor the progression of known PAD and evaluate the effectiveness of treatments such as arterial bypass grafts in the legs
  • To detect and evaluate possible arterial trauma

A stress echocardiogram helps evaluate a patient for heart disease by having them exercise on a treadmill following a predetermined protocol.  The echocardiogram is performed before exercise as a baseline and then immediately afterwards to observe any changes in the heart's wall motion.  For a stress echocardiogram to be effectively interpreted, the exercise done needs to achieve certain minimum intensity.


When coronary arteries narrow due to atherosclerotic heart disease, the heart muscle may not get enough blood supply to meet its needs during exercise.  This can cause chest pain (angina) or shortness of breath or no symptoms at all.  On a stress echocardiogram, those areas of the heart muscle not receiving enough blood flow, may not squeeze as well as other parts of the heart and will appear to have motion abnormality.  This can indicate narrowing of the coronary arteries.For a stress echocardiogram to be effectively interpreted.

An echocardiogram is an ultrasound of the heart that allows the doctor to take a closer look at how the patient's heart in functioning.  It allows the doctor to evaluate the valves and chambers of the heart in a noninvasive way so that they are able to diagnose, evaluate, and monitor:

  • Abnormal heart valves
  • Atrial fibrillation
  • Congenital heart disease
  • Damage to the heart muscle in patients who have had heart attacks
  • Heart murmurs
  • Infection in the sac around the heart (pericarditis)
  • Infection on or around the heart valves (endocarditis)
  • Pulmonary hypertension
  • The pumping function of the heart for people with heart failure
  • The source of a blood clot after a stroke or TIA

Upper Extremity Venous Ultrasound

Holter Monitor

Renal Artery Ultrasound

Segmental Ankle Brachial Index

Aortoiliac Ultrasound

Lower Extremity Arterial Ultrasound


James E. Muto, M.D., F.A.C.C.

89 Ho'okele St., Ste. 103, Kahului, HI, 96732

Phone: (808) 871-8878  Fax: (808) 871-8867

An event monitor is an extension of the holter monitor.  After the first 24 hours, the patient can take off the monitor but is asked to wear it as much as possible for anywhere from one to four weeks.  This monitor also provides real time cardiac monitoring in case of life threatening events.  These monitors are often used in cases where episodes are occurring infrequently.

The purpose of a venous duplex scan is to detect the presence of thrombus (blood clot) in your veins.  Some indications for a upper extremity venous scan include warmth, pain and swelling of one or both arms.

A renal artery ultrasound is a noninvasive examination that consists of imaging both arteries that supply blood to the kidneys and observing the flow.  The purpose of this examination is to see if there are any blockages or constrictions within the artery.  This exam may have been ordered due to  high blood pressure, previous kidney problems, or diabetes.  It is best not to eat within 6 hours of the appointment for clearer images.

The purpose of a venous duplex scan is to detect the presence of thrombus (blood clot) in your veins.  Some indications for a lower extremity venous scan include warmth, pain and swelling of one or both legs, or ulcers of legs.

The purpose of a lower extremity arterial evaluation is to detect the presence, severity and location of narrowing of the arteries caused by plaque in your legs.  Some of the indications for a lower extremity arterial evaluation include:

  • Leg pain while walking (claudication)
  • Leg pain at rest
  • Leg numbness and tingling
  • Non-healing ulcers or sores of the legs or feet.

A carotid ultrasound shows whether there is plaque or cholesterol built up in the carotid arteries. There are two common carotid arteries, one on each side of the neck.  They each divide into internal and external carotid arteries.  The internal carotid arteries supply oxygen-rich blood to the brain.  The external carotid arteries supply oxygen-rich blood to the face, scalp, and neck.

Over time, plaque can harden or rupture.  Hardened plaque narrows the carotid arteries and reduces the flow of oxygen-rich blood to the brain.  If the plaque ruptures, a blood clot can form on its surface. A clot can restrict blood flow through a carotid artery, which can cause a stroke.

An aortoiliac ultrasound helps examine the abdominal aorta and iliac arteries.  This test is used to help assess the patient for a possible aneurysm and peripheral vascular disease.  For more information on abdominal aortic aneurysms and peripheral vascular disease, please see the "Diseases & Conditions" section of our website.  To ensure clear images during the ultrasound it is advised the patient not eat a large meal within 6 hours of their appointment.

The electrocardiogram (ECG or EKG) is a noninvasive test that is used to detect underlying heart conditions by measuring the electrical activity of the heart.  Leads are placed on the body in standardized locations to record the electrical signals from the heart which can then provide information about many heart conditions by looking for characteristic patterns.  The ECG can help to measure or detect:

  • The underlying rate and rhythm mechanism of the heart.
  • Evidence of increased thickness (hypertrophy) of the heart muscle.
  • Evidence of damage to the various parts of the heart muscle.
  • Evidence of acutely impaired blood flow to the heart muscle.
  • Patterns of abnormal electric activity that may predispose the patient to abnormal cardiac rhythm disturbances.

Transcranial Ultrasound

Upper Extremity Arterial Ultrasound

Event Monitor

Lower Extremity Venous Ultrasound

Electrocardiogram (ECG)

Carotid Ultrasound

Stress Echocardiogram