Amiloidosis cardiaca por transtiretina: la gammagrafía mostró el camino / Transthyretin amyloidosis: Scintigraphy showing the way

Fundamento y objetivo: La amiloidosis cardiaca es una enfermedad grave producida por el depósito extracelular a nivel cardiaco de diversas sustancias que se identifican con el análisis de una biopsia endomiocárdica, técnica invasiva, poco accesible y de difícil interpretación. Debido a que las diversas entidades suponen diferente evolución, tratamiento y pronóstico, tiene gran relevancia clínica conocer el subtipo de esta patología. El objetivo es presentar diferentes técnicas diagnósticas no invasivas que nos puedan orientar a sospechar la amiloidosis por transtiretina. Método: Con este caso clínico reflejamos tanto la dificultad para llegar al diagnóstico del subtipo de amiloidosis como la utilidad de las pruebas radiológicas, la gammagrafía y la cardiorresonancia, en el diagnóstico diferencial de amiloidosis cardiaca. Resultados: El intenso depósito cardiaco de forma biventricular en la gammagrafía cardiaca con 99mTc-DPD como el realce tardío biventricular circunferencial en la cardiorresonancia son herramientas muy útiles para orientar hacia el diagnóstico de la amiloidosis por transtiretina.

Background and objetive: Cardiac amyloidosis is a very severe disease caused by extracellular deposition of insoluble fibrils. The gold standard for diagnosing cardiac amyloidosis is an endomyocardial biopsy. This technique is invasive, limited to experienced centers, and thus not widely available. It is required to perform special techniques to precisely determine the amyloid type as the treatment, evolution and prognosis of the disease differs greatly according the type of amyloid present. Method: In this case report we want to present the difficulties for diagnosing the types of amyloid involved in cardiac amyloidosis as well as the usefulness of cardiac MRI for diagnosing cardiac amyloidosis, particularly when performed with the use of the gadolinium as an imaging agent. Results: Biventricular, concentric late gadolinium enhancement on cardiac magnetic resonance and on technetium pyrophosphate scan (99mTc-DPD) showed to be helpful in the diagnosis of senile cardiac amyloidosis transthyrenin variant.

Obstructive sleep apnea severity is associated with left ventricular mass independent of other cardiovascular risk factors in morbid obesity.

OBJECTIVE: To evaluate the relation between obstructive sleep apnea (OSA) and left ventricular mass (LVM) in morbid obesity and the influence of gender, menopausal status, anthropometry, body composition, hypertension, and other cardiovascular risk factors in this relationship. DESIGN: Cross-sectional descriptive study. METHODS: Polysomnographic and echocardiographic studies were performed in a cohort of 242 patients (86 men, 100 premenopausal (PreM) and 56 postmenopausal (PostM) women), with grade II obesity and above (BMI: 43.7 ± 0.4 kg/m(2)) to investigate OSA and LVM respectively. Anthropometry, body composition, glucose tolerance, and blood pressure were also recorded. RESULTS: OSA to different degrees was diagnosed in 76.2% of the patients (n: 166), its prevalence being 90.9% (n: 70) for men, and 76% (n: 38) and 63.8% (n: 58) for PostM and PreM women, respectively (p < 0.01). LVM excess was greatest for PostM women (90.2%), followed by men (81.9%) and PreM females (69.6%) (p < 0.01). LVM values increased in accordance to OSA severity (absence, 193.7 ± 6.9 g; mild, 192.6 ± 7.8 g; moderate, 240.5 ± 12.5 g; severe, 273.6 ± 14.6 g; p < 0.01). LVM magnitude correlated with the menopausal state, age, central adiposity, hypertension (HT), type 2 diabetes (DM), desaturation index (DI), and apnea-hypopnea index (AHI) (r = 0.41; p < 0.01). The relationship between LVM and AHI persisted in the multivariate analysis (ß = 0.25; p < 0.05) after adjusting for age, gender, menopausal state, BMI, waist circumference, neck circumference, DI, fasting plasma glucose, DM, and HT. But if tobacco habits are included, the statistical difference disappears (ß = 0.22; p = 0.06). CONCLUSIONS: Morbid obesity is frequently associated with abnormal LVM, particularly in patients with OSA; this association is independent of HT, BMI, body composition, and other clinical factors, supporting a direct role of OSA on LVM in morbid obesity. This suggests that OSA and LVM might be taken as predictors of the cardiovascular risk in these patients.

Allograft morphology and function in heart transplant recipients surviving more than 15 years by magnetic resonance imaging and dual-source computed tomography.

OBJECTIVE: Cardiac allograft vasculopathy and late graft failure are the main limiting factors of long-term success of heart transplantation, and little is known about graft function in the long-term survivors. The aim of this study was to assess the ventricular function and the allograft vasculopathy in long-term survivors (>15 years) with the cardiac magnetic resonance imaging (MRI) and dual-source computed tomography (DSCT) coronary angiogram. METHODS: In our database, 34 cardiac recipients have more than 15 years of follow-up and were evaluated for this study; 22 (65%) of them were enrolled. Mean age at transplant was 46 ± 13.5 years, mean donor age was 28.5 ± 10.1 years, and mean graft ischemic time was 189 ± 58 min. Mean follow-up was 18.5 ± 2.4 years (range 15-22). All patients underwent cardiac MRI and DSCT. RESULTS: Mean left ventricular (LV) volumes indexed to the body surface area (BSA) were within normal range: the end-diastolic volume/BSA was 61 ± 16 ml m(-2), end-systolic volume/BSA was 22 ± 15 ml m(-2), stroke volume/BSA was 38 ± 6 ml m(-2), LV mass/BSA: 72 ± 18 g m(-2), and mean ejection fraction (EF) was 0.59 ± 0.08. Two patients (9%) showed a global cardiac hypokinesia and two other patients (9%) showed akinesia of one segment. At DSCT, 41% of patients had a strictly normal coronary angiogram, 41% had wall thickening and 18% presented a least one >60% stenosis. CONCLUSIONS: Cardiac MRI and DSCT coronary angiogram revealed a normal graft function and morphology after more than 15 years of transplantation. However, a certain number of patients have significant cardiac allograft vasculopathy and another consistent group has initial disease. These patients deserve further follow-up and tailoring of the immunosuppressive regimen.