An 80-Year-Old Man With Hypertension and Dyslipidemia With Palpitations of 2 Weeks of Evolution
An 80-year-old man with hypertension and dyslipidemia was consulted to our service with palpitations of 2 weeks of evolution. He denied shortness of breath or dyspnea on exertion. The patient had a prostate biopsy 2 months prior to our evaluation that revealed the presence of amyloid in the blood vessel walls and seminal vesicle/ejaculatory duct epithelium. These findings suggested amyloidosis. A fat pad biopsy was negative. On evaluation, his vital signs revealed a temperature of 98.5 F°, blood pressure of 130/60 mm Hg, heart rate of 120 bpm, respiratory rate of 24 respirations per minute, and SpO2 of 98%. Cardiovascular examination was within normal limits, except for an irregularly irregular rate and rhythm. Electrocardiography (ECG) was performed in our clinic that revealed coarse atrial fibrillation with rapid ventricular response (Figure 1). On the day of evaluation, his N-terminal pro-B-type natriuretic peptide was 237, and he had a glomerular filtration rate of 65 mL/min/1.73 m2. We decided to start rate control with metoprolol tartrate 50 mg orally twice a day and anticoagulation with rivaroxaban 20 mg orally daily. Days later he converted to sinus rhythm spontaneously. We ordered an echocardiogram that revealed moderate left ventricular (LV) hypertrophy, normal LV systolic function (LV ejection fraction = 60-65%) and E/E' (avg.): 13.5. Because of these findings, and to clarify the etiology of his LV hypertrophy and high filling pressures by echocardiography, we decided to perform cardiac magnetic resonance imaging (CMRI) to assess for cardiac amyloidosis (Figure 2). A bone marrow biopsy performed later revealed 11% plasma cells and markers suggestive of multiple myeloma.
What is the sensitivity and specificity of the LGE pattern in the diagnosis of cardiac amyloidosis by CMRI?