A 64-year-old postmenopausal female presents to the emergency department 2 hours after experiencing severe emotional shock following the sudden death of her spouse. She complains of acute substernal crushing chest pain and shortness of breath. ECG shows 2 mm ST-segment elevations across leads V2–V6 without reciprocal changes. Emergent coronary angiography reveals angiographically normal coronary arteries without plaque rupture, thrombosis, or focal spasm. Left ventriculography demonstrates marked apical and mid-ventricular akinesis with basal hyperkinesis ('apical ballooning') and an estimated left ventricular ejection fraction of 30%. Cardiac magnetic resonance (CMR) imaging is scheduled. What is the characteristic CMR finding that differentiates this condition from acute myocardial infarction and acute myocarditis?

A 28-year-old previously healthy woman presents with refractory hypertension (blood pressure 178/104 mmHg despite dual-agent antihypertensive therapy) and an unprovoked sudden right-sided pulsatile tinnitus. Physical examination reveals an epigastric systolic-diastolic vascular bruit and a right carotid bruit. Serum creatinine is 0.9 mg/dL and serum potassium is 3.4 mEq/L. Computed tomography angiography (CTA) of the renal and carotid arteries reveals bilateral alternating areas of arterial stenosis and aneurysmal dilation described as a 'string of beads' primarily involving the middle and distal segments of the renal arteries. What is the most definitive primary interventional therapy of choice for her renal vascular pathology?

A 52-year-old male with a history of bicuspid aortic valve presents to the resuscitation bay with sudden-onset excruciating 'tearing' chest pain radiating directly into the interscapular region. His blood pressure is 88/54 mmHg in the right arm and 84/50 mmHg in the left arm, with a heart rate of 118 bpm. Cardiac examination reveals distant heart sounds, jugular venous distention, and a new high-pitched decrescendo diastolic murmur at the right sternal border. Point-of-care transthoracic echocardiography demonstrates an intimal flap in the ascending aorta, severe aortic regurgitation, and a 1.2 cm pericardial effusion without frank diastolic right ventricular collapse. What is the immediate, most appropriate definitive management step?

A 74-year-old male with a history of bilateral carpal tunnel syndrome and lumbar spinal stenosis presents with progressive exertional dyspnea, orthopnea, and lower extremity edema over the past 8 months. 12-lead ECG demonstrates normal sinus rhythm with low QRS voltage in limb leads and pseudo-infarction QS waves in leads V1–V3. Echocardiography reveals marked symmetric concentric left ventricular wall thickening (septum 18 mm), biatrial enlargement, mildly reduced LVEF (42%), and speckle-tracking global longitudinal strain showing preserved apical strain with severe basal and mid-ventricular impairment ('apical sparing' pattern). Serum and urine protein electrophoresis with immunofixation and serum free light chain (sFLC) ratio are completely normal. What is the next most definitive non-invasive diagnostic investigation to confirm the underlying etiology?

A 23-year-old woman is brought to the hospital by her family due to dramatic behavioral changes, visual hallucinations, and acute persecutory delusions that developed over two weeks. Over the subsequent 5 days in the inpatient psychiatric unit, she developed refractory generalized tonic-clonic seizures, progressive mutism, prominent orofacial and lingual dyskinesias (lip-smacking and tongue protrusion), fluctuating hyperpyrexia, blood pressure instability, and sinus tachycardia. Brain MRI with gadolinium is normal. Routine CSF analysis reveals mild lymphocytic pleocytosis (22 WBCs/uL) with normal protein and glucose. Serum and CSF testing confirm high-titer antibodies against the GluN1 subunit of the NMDA receptor. Pelvic MRI reveals a 4.5 cm cystic and solid right adnexal mass. What is the fundamental two-pronged therapeutic strategy required for optimal long-term neurological recovery?