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Unlabelled: Single photon emission computed tomography (SPECT) myocardial perfusion imaging is widely used for diagnosing coronary artery disease (CAD). However, SPECT costs, imaging time, and radiation exposure, limit SPECT indications., Objective: Determine whether a stress-only SPECT imaging would be enough to obtain a diagnosis of CAD improving nuclear laboratory efficiency., Methods: 122 patients with unknown CAD were evaluated with stress-only SPECT imaging. In order to evaluate diagnostic accuracy and the prognostic value of the stress-only protocol, patients with abnormal SPECT underwent invasive angiography and patients with normal SPECT were followed-up during 3 years., Results: Diagnosis time, SPECT cost, and radiopharmaceutical dosage were significantly lower as compared with the conventional SPECT imaging protocol (30, 40 and 55%, respectively). Diagnostic accuracy and cardiac prognosis information were comparable to those obtained with the conventional imaging protocol (positive predictive value for CAD of 85% and negative predictive value for cardiac events of 97%)., Conclusions: In patients with intermediate risk for CAD, stress-only SPECT imaging will significantly improve nuclear laboratory efficiency, and with similar accuracy than that the one obtained with the conventional protocol.

A case of a two month infant with complex congenital heart disease (aortic coarctation with ventricular septal defect) associated to a cellular brain migration failure is presented. The management strategy consisted on the correction of congenital heart disease by means of a two-stage surgery without a further preoperative evaluation of the neurological status. The patient developed several perioperative complications such as two episodes of cardiac arrest, reconnection to cardiopulmonary bypass, cardiac tamponade, chilothorax and septic shock. A neurological protocol consisting in electroencephalography, brain magnetic resonance and Single Photon Emission Computed Tomography (SPECT) was practiced during the postoperative period, which detected microgyria with paquigyria and a cellular brain migration failure was suspected. The final outcome was death due to multisystemic failure and the autopsy confirmed the neurological disease, as well as poor life function prognosis. Should the heart-brain binomial had been considered in an integral preoperative evaluation, the therapeutical approach could have been modified.

Objective: To compare the left ventricular function and the ventricular synchrony in patients with Chagas disease in latency stage respect to a control group., Methods: We analyze a prospective, comparative, transversal and non randomized study of the left ventricular function (LVF) and the ventricular contraction synchronicity (VCS) in 36 subjects with positive serology for Chagas disease (18 males and 18 females), with mean of 15 +/- 5-years-old. The findings were compared with respect to 23 control volunteers (11 males and 12 females) with mean of 28 +/- 5-years-old. LVF and VCS were evaluated using equilibrium radionuclide angiography images (ERNA). The comparison of both Chagas and control populations was carried out by t Student test for independent samples, considering a statistically significant value of p < 0.05., Results: The parameters of the ventricular function and the ventricular synchronicity in subjects with positive serology for Chagas disease were not statistically different with respect to the parameters of the control group. However, although they have a homogeneous contraction, the mean time of contraction for the right and the left ventricle is statistically smaller with respect to the control group., Conclusions: In clinically incipient stages of Chagas disease we do not found abnormalities in the ventricular function and the ventricular synchronicity. It's necessary to consider the follow up of the studied populations using indices for the identification of abnormalities of the autonomic nervous system.

Apoptosis is a biological process of death or cellular suicide present in all the cells of the metazoans. It maintains the balance between the regeneration of pluripotential cells -or stem cells- and the elimination of cells that have already served their function, of cells that have reproduced in excess, or have been genetically damaged beyond repair. Apoptosis activation in cardiomyocytes is a common problem in a large variety of cardiomyopathies; it has been suggested that it is an important contributor ventricular hypertrophy and to the increase of the infarct size in patients with cardiac failure and cardiovascular disease. Clinical diagnosis of apoptosis is a reality in the medical science, its application in different aspects of cardiology includes from coronary cardiopathy to rhythm alterations. In this sense, the use of the non-invasive imaging, can be very useful for the in vivo detection of this type of cellular death in patients with myocardial necrosis, acute myocardial infarct, acute rejection of cardiac transplantation, myocarditis, intracardial malignant tumours, as well as in cardiotoxicity cases and other cardiomyopathies. Particularly, binding of Tc99m-labeled Annexin V, produces gammagraphic images that allow the identification of apoptotic cells in vivo in SPECT and SestaMiBi systems. In summary, the use of these techniques will be invaluable in the near future for anti-apoptosis therapy and intervention in the routine of the daily Cardiology practice.

The arrival of a patient with chest pain syndrome (precordial) to the emergency represents a diagnostic challenge for the physician. Around 6 million persons are seen each year at the Emergency units in the USA. More than half of the patients are admitted for their cardiac evaluation. Its cardiac origin is confirmed in 10 to 15%, and about 15% of them develop myocardial infarction. However, 5 to 10% of patients are dismissed and develop myocardial infarction during the next 48 h. The diagnosis of the infarct is inadvertent and/or patients is not hospitalized in 2 to 8%. The mortality rate is duplicated in none hospitalized patients. Frequently, a conservative observation conduct and/or diagnostic expectation is taken, with the consequent saturation of the intensive care unit that looses its critical character and avoids quick mobilization of the patient with an increase in costs. The clinical judgment, a meticulous clinical history, and careful physical examination play a key role in the differential diagnosis of the precordial pain syndrome; however, pain can be atypical, absent or manifest as an equivalent of pain, which does not exclude the diagnosis of myocardial infarction or ischemia. Likewise, chest pain in the presence of a normal conventional ECG at rest, non-diagnostic or with minimal variations, does not rule out the possibility of a coronary obstruction and does not mean that the pain is not of coronary origin. Other characteristics of the ECG, such as T wave and ST segment alterations, bundle branch block (BBB), LV hypertrophy, interpretation discrepancies, can pose doubts or mistakes in the diagnosis. Although its diagnostic information is essential, other non-invasive laboratory tests are needed, such as the treadmill stress ECG, serial bioenzymatic markers, and myocardial perfusion scintigraphy (SPECT and Gated-SPECT) at rest or under physical or pharmacologic stress. The advantages and disadvantages of the stress ECG, the echocardiography, magnetic resonance and PET are mentioned. The advantages of the SPECT and Gated-SPECT in the diagnosis and prognosis are: 1) great diagnostic objectivity; 2) high sensitivity and specificity; 3) diagnosis does not depend on evolution time of the ischemia and/or infarction, since SPECT diagnoses the initial primary modifications of ischemia; 4) diagnosis is achieved within the established limit of time, in less than 4 to 6 hours. The designed protocols allow to obtain the diagnosis between 30 min and 1:30 h; 5) assesses the myocardium at risk; 6) stratifies the risk and prognosis; 7) defines the site and 8) the involved coronary artery(les); 9) provides the functional significance of the anatomic obstruction; 10) quantifies the ventricular function, i.e., ejection fraction, systolic and diastolic volumes, systolic thickening, ventricular failure signs; 11) provides three-dimensional visualization of the mobility of the left ventricular wall; 12) diagnoses simultaneously the associated presence of ischemia and/or infarction of the right ventricle; 13) its high negative predictive value allows to dismiss immediately and with a great safety margin those patients in whom SPECT revealed normal perfusion; 14) costs are reduced without adversely compromising the safety of the patients. We describe the algorithm used as guideline for the early diagnosis in the presence or absence of ischemic heart disease in the patient with precordial or chest pain syndrome with normal or non-diagnostic ECG at arrival to the emergency ward. It is necessary to modified the clinical educational patterns and to revaluate the advantages and limitations of the clinical history, physical exploration, as well as of the conventional ECG at rest and other diagnostic methods used specifically in relation to the chest pain syndrome with a normal or non diagnostic conventional ECG. SPECT and Gated-SPECT scintigraphy is considered as the best individual and isolated non-invasive test for the diagnostic solution of the precordial syndrome at the Emergency Unit.