HISTORY, CURRENT ILLNESS AND PHYSICAL EXAMINATION
A 58-year-old woman consulted in the emergency department for dyspnoea.

BACKGROUND:
No known drug allergies.
Cardiovascular risk factors: no hypertension (HT), no diabetes mellitus (DM), no dyslipidaemia (DLP).
Ex-smoker of 10 cig/day for 10 years. Occasional alcohol (1 beer on weekends). No relevant medical history.
Intervened for hallux valgus in October 2017.
She does not follow usual treatment.

CURRENT ILLNESS:
58-year-old woman consulted for dyspnoea for 2-3 days with accompanying palpitations. She reported worsening of functional class with dyspnoea on moderate exertion not previously present, no orthopnoea or episodes of paroxysmal nocturnal dyspnoea. She reported feeling more swollen, with increased oedema in both ankles. This symptomatology is sometimes accompanied by palpitations. She denies fever and infectious symptoms at any level. Until now she had been asymptomatic and reported being in good health, although two months ago, during a work check-up, she was found to have a murmur which she has not paid any attention to.

PHYSICAL EXAMINATION:
Blood pressure (BP) 125/66 mmHg, heart rate (HR) 140 bpm, oxygen saturation 94% at baseline. Afebrile. Jugular venous engorgement. Cardiac auscultation: arrhythmic, mitral systolic murmur II/IV. Pulmonary auscultation: minimal crackles in right base, rest of pulmonary auscultation normal. Lower extremities: oedema with bimalleolar fovea, rest normal.

COMPLEMENTARY TESTS
ANALYTICS: haemoglobin 12.4 mg/dl. Haematocrit 38.1%. Leukocytosis 9,760 x 1000 with normal formula. Platelets 235,000 /ml. Coagulation: INR 1.08; PT 13.2 sg APTT 23.2 sg. Biochemistry: glucose 125 mg/dl. Creatinine 0.92 mg/dl. Urea 53 mg/dl. Sodium 135 mmol/l. Potassium 4.1 mmol/l.
Liver profile normal. CRP 21.9 mg/dl. ProBNP 2841 pg/ml.
CARDIAC MARKERS: troponin T and CPK normal, without serum changes.
THORAX RADIOGRAPHY: cardiothoracic index at the upper limit of normality. Right pleural effusion with pinching of the sinocostophrenic sinus. Fluid in the cisuras.
Electrocardiogram (ECG): atrial fibrillation (AF) at 140 bpm with right bundle branch block (RBBB) and left anterior hemiblock (LABB).
CLINICAL COURSE
After a first episode of HF related to recently diagnosed AF with high ventricular rate, diuretic treatment, anticoagulation and beta-blocker treatment were started to control the heart rate, and the patient was admitted to cardiology for study and management.
During his admission to the cardiology ward, a transthoracic echocardiogram was performed.
Transthoracic echocardiogram: left ventricle slightly dilated (85 ml/cm2) with normal wall thickness. Global and segmental systolic function preserved. Severely dilated left atrium (100 ml/cm2). Large mass (area 13.6 cm2) hyperechogenic with partial calcification, with very friable edges, prolapsing inside the LV and preventing proper closure of the mitral valve. Probable point of anchorage at the level of the interatrial septum below and posterior to the foramen ovale. Normal sized right chambers with preserved ejection fraction (RVEF). Trivial tricuspid insufficiency allowing estimation of pulmonary arterial systolic pressure (PSAP) of 38 mmHg. Anatomically and functionally normal aortic valve. Mitral valve with thickening of both leaflets, difficult to assess anatomically due to the imprint of the left atrial mass. Severe mitral insufficiency, eccentric jet. Inferior vena cava of normal size with physiological inspiratory collapse. Aortic root, ascending aorta and infrarenal abdominal aorta of normal size. Absence of pericardial effusion.
In view of the echocardiographic findings, the need for surgical intervention was discussed with the patient. Coronary angiography was performed, showing right dominance and coronary arteries without lesions.
The patient was scheduled for cardiac surgery where a voluminous tumour with a wide implantation base was visualised. The anterior mitral leaflet was compromised at A1-A2 and the anterior mitral annulus, making valve repair impossible, and a St. Jude type mechanical prosthesis no. 29 was implanted.
The anatomopathological report shows a mesenchymal lesion of low histological aggressiveness in which the hyallino-myxoid stroma predominates on which small cell groups with little cytological atypia float, although some present hyperchromatic nuclei, with abundant thin-walled vessels. No mitotic figures or foci of necrosis are observed. Areas of dystrophic calcification are observed. Pathological diagnosis: cardiac myxoma.

DIAGNOSIS
Intracardiac mass. Cardiac myxoma.
First episode of HF.
Newly diagnosed AF with rapid ventricular response.
CHADS-VASC 2
Arterial hypertension.
