La sostenibilidad de los diagnósticos por la imagen en cardiología

Cada año se practican cinco mil millones de pruebas diagnósticas de imagen, de las que aproximadamente la mitad son exámenes cardiovasculares. Según las estimaciones más recientes, del 30 al 50% de todos esos exámenes son parcial o totalmente inapropiados: ello significa un daño potencial para los pacientes afectados (porque asumen los riesgos considerables de un procedimiento agresivo y/o de un estudio de contraste sin un beneficio equivalente al riesgo), un costo exorbitante para la sociedad y un retraso excesivo para los demás pacientes de las listas de espera necesitados de examen. En el caso de pruebas con uso de radiaciones ionizantes, la reducción del número de pruebas innecesarias representaría una mejoría en la atención al paciente, incluida la disminución de los riesgos a largo plazo, asociados a la dosis empleada. La dosis de radiación equivalente de las pruebas cardiológicas de imagen corresponde a unas 500, 750 y 1.000 placas radiográficas de tórax para un escintigrafía cardíaca con sestamibi, el CT coronario y la coronarografía con stent coronario, respectivamente. Aunque no se dispone de la evaluación directa de la incidencia de cáncer en los pacientes sometidos a tales procedimientos, el riesgo de cáncer estimado para un CT coronario es alrededor de 1/750; el riesgo es mayor en mujeres(alrededor de 1/500), menor en ancianos (1/1.500) y mayor en niños (1/1.000 en niñas menores de un año). Tales niveles de riesgo son inaceptables cuando se usa el procedimiento diagnóstico en cribas poblacionales o cuando puede obtenerse la información mediante el uso de otros medios, pero son aceptables en grupos seleccionados como filtro de procedimientos más invasivos, peligrosos y costosos.Every year, 5 billion imaging testing are performed worldwide, and about 1 out of 2 are cardiovascular examinations. According to recent estimates, 30 to 50% of all examinations are partially or totally inappropriate. This represents a potential damage for patient undergoing imaging (who takes the acute risks of a stress procedure and/or a contrast study without a commensurable benefit), an exorbitant cost for the society and an excessive delay in the waiting lists for other patients needing the examination. In case of ionizing tests, the reduction of useless imaging testing would improve the quality of care also through abatement of long-term risks, which are linked to the dose employed. The radiation dose equivalent of common cardiological imaging examinations corresponds to about 500, 750 and 1000 chest x-rays for a stress sestamibi, a multislice cardiac computed tomography and a coronary stenting respectively. Although a direct evaluation of incidence of cancer in patients submitted to these procedures is not available, the estimated risk of cancer according to the latest 2006 Biological Effects of Ionizing Radiation Committee VII is about one in 750 for a CT scan – higher in women (1 in 500), lower in elderly (1 in 1,500), and highest in children (1 in 100 in a female child <1 year). Such a risk is probably not acceptable when a diagnostic procedure is inappropriately applied for mass screening (when the risk side of the risk-benefit balance is not considered) or when a similar information can be obtained by other means. By contrast, it is fully acceptable in appropriately selected groups as a filter to more invasive, risky and costly procedures

WEB downloadable software for training in cardiovascular hemodynamics in the (3-D) stress echo lab

When a physiological (exercise) stress echo is scheduled, interest focuses on wall motion segmental contraction abnormalities to diagnose ischemic response to stress, and on left ventricular ejection fraction to assess contractile reserve. Echocardiographic evaluation of volumes (plus standard assessment of heart rate and blood pressure) is ideally suited for the quantitative and accurate calculation of a set of parameters allowing a complete characterization of cardiovascular hemodynamics (including cardiac output and systemic vascular resistance), left ventricular elastance (mirroring left ventricular contractility, theoretically independent of preload and afterload changes heavily affecting the ejection fraction), arterial elastance, ventricular arterial coupling (a central determinant of net cardiovascular performance in normal and pathological conditions), and diastolic function (through the diastolic mean filling rate). All these parameters were previously inaccessible, inaccurate or labor-intensive and now become, at least in principle, available in the stress echocardiography laboratory since all of them need an accurate estimation of left ventricular volumes and stroke volume, easily derived from 3 D echo

Emergency radiology without the radiologist: the forensic perspective

Purpose. The aim of this paper is to describe two cases from the authors\u27 forensic archive database in which teleradiology was related to unfavourable outcomes. Material and methods. Two patients underwent autopsy after unexpected death following road accidents. In one case, death was caused by multiple cervical fractures following minor neck injury in the presence of diffuse idiopathic skeletal hyperostosis. In the other case, death was due to delayed isthmic aortic rupture occurring after thoracic blunt trauma in a young adult. Both conditions were diagnosed at autopsy only. Results. In both cases, the lethal outcome was due to the failure to obtain radiological reports of the X-rays performed in the emergency department. Radiological diagnoses could have been established by activating the teleradiology service which, according to the hospitals\u27 teleradiology protocols, is available on demand in cases of emergency only, as selected by the physician requesting the service. Conclusions. These cases suggest the high risk of excluding the radiologist from the management of patients whose images are transmitted via a teleradiology system.Obiettivo. Gli autori intendono descrivere due casi tratti dal proprio archivio autoptico medico-legale nei quali l\u27esito sfavorevole ? connesso all\u27uso della teleradiologia. Materiali e metodi. Sono descritte le risultanze dell\u27indagine autoptica eseguita su due soggetti deceduti in maniera inattesa dopo incidente della strada. In un caso la morte ? dipesa da fratture cervicali multiple determinatesi, in soggetto affetto da DISH (iperostosi scheletrica idiopatica diffusa), per un trauma minore del collo. Nel secondo caso un giovane adulto riportava una contusione del torace con "rottura in due tempi" dell\u27istmo aortico. Entrambe le patologie traumatiche sono state diagnosticate solo in sede di esame autoptico. Risultati. La mancata diagnosi in vita ha tratto origine, in entrambi i casi, dalla "non refertazione" degli esami radiologici eseguiti in urgenza; la diagnosi radiologica avrebbe potuto effettuarsi mediante attivazione del sistema di teleradiologia, utilizzabile, secondo il protocollo gestionale della struttura, solo in casi urgenti, selezionati dal medico richiedente la prestazione. Conclusioni. Questi due casi suggeriscono che l\u27esclusione del radiologo dalla gestione dei pazienti le cui immagini sono trasmesse in teleradiologia comporta un rischio molto elevato di prestazioni inadeguate

The Risks of Inappropriateness in Cardiac Imaging

The immense clinical and scientific benefits of cardiovascular imaging are well-established, but are also true that 30 to 50% of all examinations are partially or totally inappropriate. Marketing messages, high patient demand and defensive medicine, lead to the vicious circle of the so-called Ulysses syndrome. Mr. Ulysses, a typical middle-aged “worried-well” asymptomatic subject with an A-type coronary personality, a heavy (opium) smoker, leading a stressful life, would be advised to have a cardiological check-up after 10 years of war. After a long journey across imaging laboratories, he will have stress echo, myocardial perfusion scintigraphy, PET-CT, 64-slice CT, and adenosine-MRI performed, with a cumulative cost of >100 times a simple exercise-electrocardiography test and a cumulative radiation dose of >4,000 chest x-rays, with a cancer risk of 1 in 100. Ulysses is tired of useless examinations, exorbitant costs. unaffordable even by the richest society, and unacceptable risks

Trends of Increasing Medical Radiation Exposure in a Population Hospitalized for Cardiovascular Disease (1970-2009)

Abstract Background: High radiation doses employed in cardiac imaging may increase cancer frequency in exposed patients after decades. The aim of this study was to evaluate the relative trends in medical radiation exposure in a population hospitalized for cardiovascular disease. Methods and Results: An observational single-center study was conducted to examine 16,431 consecutive patients with heart disease admitted to the Italian National Research Council Institute of Clinical Physiology between January 1970 and December 2009. In all patients, the cumulative estimated effective dose was obtained from data mining of electronic records of hospital admissions, adopting the effective dose typical values of the American Heart Association 2009 statement and Mettler\u27s 2008 catalog of doses. Cumulative estimated effective dose per patient in the last 5 years was 22 (12-42) mSv (median, 25th-75th percentiles), with higher values in ischemic heart disease (IHD), 37 (20-59) vs non-IHD, 13 (8-22) mSv, p,0.001. Trends in radiation exposure showed a steady increase in IHD and a flat trend in non-IHD patients, with variation from 1970-74 to 2005-2009 of +155% for IHD (p,0.001) and 21% in non-IHD (NS). The relative contribution of different imaging techniques was remodeled over time, with nuclear cardiology dominating in 1970s (23% of individual exposure) and invasive fluoroscopy in the last decade (90% of individual exposure). Conclusion: A progressive increase in cumulative estimated effective dose is observed in hospitalized IHD patients. The growing medical radiation exposure may encourage a more careful justification policy regarding ionizing imaging in cardiology patients applying the two main principles of radiation protection: appropriate justification for ordering and performing each procedure, and careful optimization of the radiation dose used during each procedure

The association of micronucleus frequency with obesity, diabetes and cardiovascular disease

Obesity and metabolic syndrome (MetS) are serious and growing health care problems worldwide, leading an increased risk for type 2 diabetes (T2D) and cardiovascular disease (CVD). Over the past decade, emerging evidence has shown that an increased chromosomal 20 damage, as determined by the cytokinesis-block micronucleus (CBMN) assay, is correlated to the pathogenesis of metabolic and CVD. An increased micronuclei (MN) frequency has been demonstrated in peripheral blood lymphocytes of patients with polycystic ovary syndrome, 25 a common condition in reproductive-aged women associated with impaired glucose tolerance, T2D mellitus and the MetS. High levels of MN have been detected to be significantly correlated with T2D as well as with the occurrence and the severity of coronary artery disease 30 (CAD). Long-term follow-up studies have shown that an increased MN frequency is a predictive biomarker of cardiovascular mortality within a population of healthy subjects as well as of major adverse cardiovascular events in patients with known CAD. Overall, these findings 35 support the hypothesis that CBMN assay may provide an useful tool for screening of the MetS and its progression to diabetes and CVD in adults as well in children. Large population-based cohorts are needed in order to compare the MN frequencies as well as to better define whether MN 40 is a biomarker or a mediator of cardiometabolic diseases

Does the combination with handgrip increase the sensitivity of dipyridamole-echocardiography test?

The aim of this study was to assess the possibility of increasing the sensitivity of dipyridamole-echocardiography testing (DET:2-D echo monitoring during dipyridamole infusion) by combining this procedure with handgrip testing. Dipyridamole-handgrip test (DHT) was therefore performed in 24 patients with rest/effort angina, negative DET, and negative handgrip-echo (without dipyridamole pretreatment). DHT consisted of 4.5 min of sustained 25% maximum grip strength, started 4 min after the end of dipyridamole infusion (0.56 mg/kg for 4 min). Interpretable studies were obtained in all patients. Of the 24 patients tested (10 without and 14 with significant coronary artery disease, CAD), only one CAD patient had a positive DHT, which indicates an increased sensitivity of 7% versus DET alone. In conclusion, DHT is feasible in all patients and--if compared to DET--has the same specificity. However, in spite of the theoretical premises, it provides only a modest step up in sensitivity

Prognostic Correlates of Combined Coronary Flow Reserve Assessment on Left Anterior Descending and Right Coronary Artery in Patients with Negative Stress Echocardiography by Wall Motion Criteria.

Aims: To assess the prognostic correlates of Doppler echocardiographically derived coronary flow reserve (CFR) on two coronaries in patients with negative stress echo. Vasodilator stress echocardiography allows dual imaging of regional wall motion and CFR both on left anterior descending (LAD) and right coronary artery (RCA). Methods: The study group comprised 460 patients with known or suspected coronary artery disease and negative stress echo by wall motion criteria. All underwent dipyridamole (up to 0.84 mg/kg over 6 minutes) stress echo with CFR evaluation of either LAD or RCA by Doppler, and were followed up for a median of 32 months. A CFR value of(2.0 was taken as abnormal. Results: CFR was abnormal in 174 patients (38%) (57 in LAD only, 48 in RCA only, and 69 in both LAD and RCA) and normal in 286 patients (62%). During follow-up, there were 77 cardiac events: 5 deaths, 44 acute coronary syndromes (6 STEMI, and 38 NSTEMI) and 28 late (.6 months from stress echo) revascularisations. CFR of (2.0 on LAD was the strongest multivariable predictor of either definite (death, acute coronary syndrome) and major (death, acute coronary syndrome, late revascularisation) events, followed by diabetes mellitus. Antiischaemic therapy at the time of testing and resting wall motion abnormality were also independently associated with major events. Preserved CFR in both LAD and RCA was associated with better (p,0.0001) definite and major event-free survival compared to abnormal CFR in one or both coronary vessels. Conclusion: CFR evaluation of either LAD or RCA allows the identification of distinct prognostic patterns. In particular, preserved CFR in both coronary vessels is highly predictive of a very favourable outcome, while reduced CFR in either coronary vessel, and especially on LAD, is a strong predictor of future cardiac events