Soru

A $67$-year-old woman is evaluated in the cardiac intensive care unit after a sudden episode of unresponsiveness. She was admitted $4$ days ago for an acute anterior ST-segment elevation myocardial infarction and underwent successful percutaneous coronary intervention of the left anterior descending artery. Her medical history is notable for hypertension, type 2 diabetes mellitus, and a $40$-pack-year smoking history. Following the episode of unresponsiveness, she quickly regains consciousness but reports feeling extremely weak and lightheaded. Her temperature is $36.7^\circ\text{C}$ ($98.1^\circ\text{F}$), blood pressure is $72/40$ mm Hg, pulse is $126$/min and regular, and respirations are $26$/min. Pulse oximetry is $93\%$ on room air. Physical examination reveals cold, clammy extremities and significant jugular venous distention. The apical impulse is not palpable. Lung fields are clear to auscultation bilaterally. Heart sounds are distant, and no murmurs, rubs, or gallops are appreciated. An electrocardiogram shows sinus tachycardia and persistent ST-segment elevations in the anterior leads, unchanged from the post-intervention electrocardiogram. Arterial blood gas analysis on room air reveals a pH of $7.24$, pCO $_2$ of $32$ mm Hg, and pO $_2$ of $68$ mm Hg. Which of the following is the most appropriate next step in the management of this patient?