Papers by Erick Alexanderson
![Research paper thumbnail of [Usefulness of nuclear techniques in the study of myocardial viability]](https://a.academia-assets.com/images/blank-paper.jpg)
Archivos de cardiología de México
The assessment of myocardial viability in patients with coronary artery disease and left ventricu... more The assessment of myocardial viability in patients with coronary artery disease and left ventricular dysfunction is of great diagnostic and prognostic value. The identification of myocardial viability, in patients with coronary artery disease and left ventricular dysfunction is useful in risk stratification, for it allows the prediction of a group of patients that may benefit the most from a revascularization procedure. The revascularization of dysfunctional (asinergic) segments showing viability in patients with coronary artery disease and left ventricular dysfunction has been associated to improved survival and New York Heart Association (NYHA) class. An improvement in global as well as in regional left ventricular function has also been described. Currently, several non-invasive imaging techniques have been used to assess myocardial viability, among them, nuclear cardiology methods are the most employed. TI-201 SPECT imaging (stress-redistribution-reinjection) is one of the most commonly used, because of its availability, cost, and correlation with 18-FDG PET studies, which is considered the gold standard among imaging techniques for the detection of myocardial viability. Therefore, if PET is available, it should be used in patients with coronary artery disease and moderate to severe left ventricular dysfunction.
Archivos de cardiología de México
Antecedentes : Recientemente se ha propuesto el empleo del SPECT sincronizado para la medición de... more Antecedentes : Recientemente se ha propuesto el empleo del SPECT sincronizado para la medición de fracción de expulsión, volúmenes y movilidad de la pared ventricular. El objetivo de este estudio es evaluar la fracción de expulsión (FE) obtenida con el programa de SPECT ...
Archivos de cardiología de México
Archivos de cardiología de México
ABSTRACT
Archivos de cardiología de México
Archivos de cardiología de México
Cardiovascular magnetic resonance (CVMR) is the best non invasive imaging technique for the diagn... more Cardiovascular magnetic resonance (CVMR) is the best non invasive imaging technique for the diagnosis of congenital heart disease (CHD) as it gives important information concerning anatomy and function of the heart in the same exploration. This method is useful for the follow up of the patient with congenital heart disease. The most important benefits of CVMR are the non invasiveness of the same and the lack of ionic radiation. The objective of this article is to demonstrate that congenital heart disease can be diagnosed with CVMR with a higher precision compared with other cardiovascular imaging techniques.
Archivos de cardiología de México
Resumen La arteritis de Takayasu (AT), es una enfermedad crónica que afecta principalmente a la a... more Resumen La arteritis de Takayasu (AT), es una enfermedad crónica que afecta principalmente a la aorta y sus ramas. Su etiología aún es desconocida, sin embargo se sabe que existe un predominio por el género femenino y que inicia generalmente en los ...
Archivos de cardiología de México
Background: In patients with myocardial infarction and left ventricular dysfunction, the evidence... more Background: In patients with myocardial infarction and left ventricular dysfunction, the evidence of myocardial viability is primordial. There are some methods to detect the presence of myocardial viability, 201 thallium reinjection SPECT protocol represents the most common ...
Archivos de cardiología de México
... Correspondencia: Dr. Erick Alexánderson Rosas. ... Los miocitos que se encuentran en este est... more ... Correspondencia: Dr. Erick Alexánderson Rosas. ... Los miocitos que se encuentran en este estado hibernante adoptan un fenotipo embriónico demostrado mediante la presencia de la expresión de acuna en el músculo liso y la de proteínas propias del citoesqueleto como la ...
Archivos de cardiología de México
Archivos de cardiología de México
In patients with myocardial infarction and left ventricular dysfunction, the evidence of myocardi... more In patients with myocardial infarction and left ventricular dysfunction, the evidence of myocardial viability is primordial. There are some methods to detect the presence of myocardial viability, 201 thallium reinjection SPECT protocol represents the most common radioisotopic technique to evaluate it. Positron emission tomography (PET) using FDG is considered the gold standard. The aim of this study was to compare globally and by segments the value of both techniques in the detection of viable myocardium. Twenty-three consecutive patients with previous myocardial infarction and left ventricular dysfunction were studied. All of them underwent into a SPECT perfusion scan and a FDG PET study to asses myocardial viability. Each study was performed in less than one week between the other. For the analysis, the myocardium was divided into 17 segments. A visual semi-quantitative analysis was carried out according to the following score indicating radiotracer uptake: O = normal to 4 = absent. Myocardial viability was defined as the presence of normal, mildly or moderately reduced radiotracer uptake. The scores obtained by PET were compared to those obtained in SPECT. A statistical analysis was performed using the SPSS v. 10. 391 segments were analyzed. PET detected viability in 130 segments that had been defined as non-viable by SPECT. No differences in the analysis by vascular territories were found. Thirty percent of the segments that were defined as non viable by SPECT were viable by PET, meanwhile only 1% of the segments detected viable by SPECT were considered non viable with PET. FDG PET study represents a better technique to detect myocardial viability, compared to thallium reinjection SPECT protocol. By this study we have demonstrated that more of 3 of each 10 studies may be diagnosed as non viable where viability is present.
Archivos de cardiología de México
Serial assessment of ventricular function by means of radionuclide angiography was performed in p... more Serial assessment of ventricular function by means of radionuclide angiography was performed in previously untreated patients with lymphoproliferative diseases who received either 4'epidoxorubicin or mitoxantrone for longer than 6 months. No changes were observed in left ventricular function in patients received mitoxantrone at doses ranged 90 to 165 mg (mean 113 mg). Three patients (7%) in 4'epidoxorubicin group showed less than or equal to 10% drop in left ventricular ejection, but without clinical manifestations. The doses in this group were 420 to 810 mg (mean 610 mg). We felt that patients without high-risk factors (radiotherapy to mediastinum or previously anthracycline therapy) could be treated with high doses of both drugs and that radionuclide angiography is a useful method for monitoring cardiotoxicity of antineoplastic drugs.
Archivos de cardiología de México
ABSTRACT
Archivos de cardiología de México
... y medicina nuclear en afección cardiovascular de origen autoinmune Nilda Espinola Zavaleta,* ... more ... y medicina nuclear en afección cardiovascular de origen autoinmune Nilda Espinola Zavaleta,* Erick Alexánderson ,** María Elena Soto,*** Maricela Flores,* Mary-Carmen Amigo**** * Departamento de Ecocardiografía de Consulta Externa, INCICH. ...
Archivos de cardiología de México
A significant correlation between autoimmune diseases such as systemic lupus erythematosus (SLE),... more A significant correlation between autoimmune diseases such as systemic lupus erythematosus (SLE), rheumatoid arthritis (RA) and premature or accelerated coronary atherosclerosis was found. The objectives of the study were: a) evaluate myocardial perfusion in patients with rheumatic diseases by means of contrast echocardiography (CE) and to establish its usefulness as compared to the results obtained by nuclear medicine (NM) (reference method). b) evaluate the prevalence of alterations in subclinical myocardial perfusion in autoimmune diseases and to establish a strategy to evaluate the cardiovascular changes in this disease. Myocardial perfusion in 37 outpatients of the rheumatology department was evaluated by CE at rest and with pharmacological stress (dobutamine) and NM. The prevalence of alterations in the myocardial perfusion in autoimmune diseases by CE and NM, when these methods were analyzed independently or when both methods were used was 27%. The positive predictive value (PPV) and negative predictive value (NPV) of both tests was 80% and 93%, respectively, the sensitivity was 80% and the specificity was 93%. The prevalence of alterations of perfusion in the primary antiphospholipid syndrome (PAPS) was of 30%. In this patients it was found that when both diagnostic tests are performed, NM reaches a sensitivity of 100% if the CE is positive and an specificity of 100% when the CE is negative. We can conclude that it is important to determine the presence of subclinic coronary artery disease in patients with autoimmune disease by noninvasive studies such as Sestamibi SPECT and/or CE for assessment of myocardial perfusion in order to plan an adequate treatment and follow-up.
Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital
A 2-year-old girl in whom a cardiac murmur had been detected at the age of 4 months underwent phy... more A 2-year-old girl in whom a cardiac murmur had been detected at the age of 4 months underwent physical examination. She had no cyanosis, but a continuous murmur was detected. The murmur was centered in the 4th right intercostal space and radiated vertically. The echocardiogram showed right coronary artery (RCA) dilation.
Introduction: Transtelephonic monitoring of pacemakers (TTM) has been established at our institut... more Introduction: Transtelephonic monitoring of pacemakers (TTM) has been established at our institution for several years, however, the program has not yet been systematically evaluated. Aims: To assess feasibility and effectiveness of the TTM program, to perform a cost-benefit analysis in comparison to clinic follow-up and to determine the role of TTM in the follow-up of recalled pacemakers (that typically require more intensified follow-up). Methods: Retrospective analysis of the electronic charts of all patients in the TTM program from Jan 1st to Oct 30th, 2006 was undertaken. For cost-benefit analysis, a virtual model of in-office visits was created. A LifeSignsTM Receiving Center, Instromedix; was used for TTM decoding and recording. Results: During the screened period, 303 patients had 1468 encounters (4.7 Ϯ 2.8 encounters per patient), mean age was 81.6 Ϯ 10.2 years old (range 40 -102), 51.2% female. Pacing mode was single chamber in 55%. The reasons for a TTM strategy included anticipated impending failure of the battery (50%), immobility of the patient (50%), living far from the hospital (47%), device under "recall" (6%). 56% of the patients evaluated monthly and 44% evaluated every three months. Patients on a monthly schedule were more likely to be directed to attend the clinic in person (4.9% vs. 2.1%; pϽ0.02). Reasons for direct the patient to the clinic in person were: Elective Replacement Indication 30%, technical difficulties 4%, regular annual visit 66%. Dual chamber pacemakers (pϭ0.004), longevity of the battery (pϽ0.03) and reduced mobility of the patient (pϭ0.02) were significantly associated with referrals to the pacemaker clinic. One patient was lost to follow-up (0.3%) and 12 patients (4%) died during this period. Only age (80.5 vs. 87.3 years old; pϽ0.02) and reduced mobility (pϭ0.001) were associated with death during follow-up. The cost of the TTM strategy for this cohort was $11,744.00. A cost model calculated based on attendance of all TTM patients at the clinic at the same follow-up frequency resulted in an estimate of $88,230.00 -approximately 8 times more costly than the TTM strategy. Conclusion: TTM for pacemaker follow-up is safe and permits follow-up for patients who have difficulty coming to the clinic. Large numbers of patients can be followed in a cost effective manner. TTM may be an effective and palatable way to provide more frequent follow-up for some "recall" patients.
Archivos de cardiología de México
ABSTRACT
Archivos de cardiología de México
The endothelium plays an important role in the regulation of the intracellular fluid, vascular pe... more The endothelium plays an important role in the regulation of the intracellular fluid, vascular permeability, and modulation of vascular focal tone and angiogenesis. Endothelial dysfunction is manifested by the loss of the endothelium ability to modulate physiology changes in its vascular bed, and actually it is considered a prognostic marker of coronary artery disease. The relevance of assessing endothelial dysfunction relies in that it has been observed in different pathologies like DM, dyslipidemia, hypertension, tabaquism and in immunologic diseases like antiphospholipid syndrome and systemic lupus. PET is a non invasive method that allows the absolute quantification of myocardial blood flow during rest, stress and adrenergic stimulation, which allows to asses endothelial function. Therefore PET is a useful diagnostic technique to identify patients with endothelial dysfunction, and in the assessment of its response to administered therapy, allowing an optimal control and prevention of secondary adverse events of these diseases.
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Papers by Erick Alexanderson