Nuclear Cardiology

Nuclear Cardiology studies done by Cardimax services follow the standardized methodology recommended by The American Society of Nuclear Cardiology.

Staff with current certification.

The study of perfusion (SPECT myocardial blood circulation within the contractile muscular walls of the heart), or gated SPECT myocardial is the study of cardiac imaging non-invasive most sought-after in the world: more than 10 million of them every year just in the United States of North America, their number will continue to increase in the following years.

You have different protocols: scan heart or myocardial perfusion SPECT MIBI, tetrofosmin, thallium, Dual, among others.

The gated SPECT (single photon emission computed tomography or computed by single photon emission tomography), is a technique of diagnostic advanced non-invasive, studying the circulation on the walls of the heart, analyzes their mobility and other parameters, resting and exertion; analysis of mobility and contractile function of the heart is possible thanks to the synchronization (gated function) of the acquisition of images with each heartbeat, or cardiac cycle.

The cardiac SPECT scan information can define the treatment that is best stable patients with cardiac infarction, angina chest or suspected of obstructive disease of the blood vessels of the heart or coronary arteries, to indicate if this is good or bad circulation (to poor circulation of blood within the heart muscle and contractile walls known as ischemia).

In such patients, the gated SPECT defines if catheterization and stent or coronary revascularization (Ventricle or bypass) surgery, are or are not useful.

Basic aspects of the study of SPECT nuclear Cardiology

  • It is not invasive: is not an surgery.
  • It is safe and reliable.
  • No anaesthesia or hospitalization is required.
  • It has the best predictive value annual forecast:
    • 98.2% to 99.4% of patients with a normal SPECT, do not present either infarction or death of cardiac origin.
    • SPECT is a powerful predictor of cardiac risk widely studied.
  • Its prognostic value, i.e., its power to predict who will give a heart attack and who is not, the most accurate, it has been widely validated by monitoring for 10 years of more than 69,000 patients; This predictive value forecast for major cardiovascular event (death or non-fatal heart attack), is also independent of the results of coronary catheterization.

Results in more than 69,000 patients, followed 10 years: Prognostic value of gated myocardial perfusion SPECT. Leslee J. Shaw PhD and Ami E. Iskandrian MD: Journal of Nuclear Cardiology, Vol. 11 No. 2; 171-85. 2004.

Examples of the usefulness of SPECT to indicate or contraindicate catheterization with stent or surgery coronary artery bypass, coronary or bypass, in stable coronary patients bridge.

Case 1-use of nuclear Cardiology to know if it is important or do a catheterization and install a stent:

Man of 50 years of age, with a cardiac infarct started more than 12 hours ago, P.A. 120 / 70 mm. Hg. F.C. 85 per minute (stable heodinamicamente), without arrhythmia and now pain-free, presents lack of mild air to walk more than 300 meters.

Traditional old behavior: became catheterization and placed a stent that repermeabilizo or "uncovered" coronary artery blocked, infarct, successful procedure.

Result: Catheterization, which opened the artery, but useless for the patient who had no improvement: because the patient followed with shortness of breath; A study of SPECT nuclear Cardiology showed that the area of the infarct, which is a dead heart (heart attack, green arrows, right image) did not have improvement in the bloodstream within the walls of the area of the infarct heart, although it has been made catheterization and installed a stent so that improvement to occur.

Correct current behavior: conduct current more accepted as beneficial to the patient: do before catheterization study of Nuclear Cardiology or study of myocardial perfusion gated SPECT in a stable heart attack, to know if there is or non-woven salvageable live within the area of the infarct, scenario where Yes this indicated the catheterization and stent.

The patient from the image in particular, catheterization and stent will not increase your survival or will decrease you your risk of reinfarction.

There is not a single publication with statistical and methodological quality in serious medical literature, that evidence to the contrary.

In this case, the catheterization, which is usually an excellent therapeutic procedure when it is well indicated, did not benefit the patient and would have even avoided a nuclear Cardiology Spect study done before

Case 2-utility of nuclear Cardiology for saving of costs at a stroke:

59 year old woman, with a stroke started more than 12 hours ago. 130/70 mm P.A. Hg. It has no post infarction arrhythmias. Asymptomatic and stable cardiovascular. Without angina pain.

Ancient or traditional conduct: became you catheterization without stent, only a diagnostic catheterization, which showed 2 arteries diseased coronary arteries narrow (picture at right, yellow arrows), compared to the thickness of arteries healthy (red arrows). Is proposed to install 4 stent by catheterization to open the 2 narrow arteries and improve blood flow; the estimated cost was $20,000 by the proposed procedure; the patient did not accept.

Current behavior correct or accepted as of benefit to the patient: make a myocardial perfusion gated SPECT, also known as study of nuclear cardiology, before catheterization.

In this case the gated SPECT was made after diagnostic catheterization and showed a large infarction, without living residual tissue (left, green arrows) in the territory of the diseased arteries; Nothing would have served the patient open arteries sick with the 4 stent in a second catheterization, or pay for it more than $20,000, because they would bring blood to a dead zone of the heart, which is the area of infarction.

Compare the Spect of the patient (left), with one normal without infarction (middle box).

R: Rest
S: Stress

Do before catheterization study of nuclear Cardiology or myocardial perfusion gated SPECT, this woman, would have prevented the catheterization; in this particular case, as well as the installation of the stent, have improper use criteria. JACC.2012; 59:857-881.

Case 3: usefulness of gated SPECT myocardial to indicate a catheterization with stent.

Man with chest pain to the effort that is removed at rest; (stable angina pectoris). In cardiac SPECT scan or live tissue perfusion gated SPECT, (left) shows study with normal circulation in the heart at rest (yellow arrows, R: rest), and that effort presents ischemia (poor circulation with risk of heart attack), in the lower wall, (green arrows, S: effort). Heart (right) tomography, showed the blockage of the right coronary artery, (blue arrows), responsible for poor circulation or ischemia in lower wall. The cardiac SPECT scan showed ischemia and the usefulness of catheterization to remove it, thus reducing the risk of a heart attack, opening the artery clogged with a stent, (AUC: JACC.2012; 59:857-881) was made. Tomography of the heart may help decrease radiation and contrast used in the catheterization.

Case 4:

With pain by angina pectoris effort (stable angina pectoris), 50-year-old woman, he started 6 months before, has high cholesterol 290 mg. dl. LDL 140 mg. dl. P.A. 140/90 mm. Hg. weighs 80 kg and is 162 cm. ECG wave T negative from V1 to V3.

(Traditional) old behavior: do the invasive catheterization for the arteries of the heart, as he was proposed by a first doctor reviewed the patient, this did not accept the procedure

Current behavior: a study of nuclear Cardiology SPECT East turned out normal and avoided the catheterization. It gave medical management, diet, and cardiac rehabilitation program; It is healthy.

50% of women with angina pectoris in peri-menopausica age, have normal coronary arteries.

SPECT study may prevent or indicate catheterization.

In this case, the SPECT avoided the catheterization.