A 32-Year-Old Woman Comes to the Emergency Department Due to Progressive

A 32-year-old woman comes to the emergency department due to progressive weakness and shortness of breath over the last several weeks.  The patient has had no chest pain, palpitations, or syncope.  She has not had any recent upper respiratory infection.  Medical history is significant for migraine headaches for which she takes ibuprofen a few times per week.  She does not take any other over-the-counter or prescription medications.  The patient has had 2 cesarean sections, most recently 2 years ago.  She has smoked a pack of cigarettes a day since age 17 and uses methamphetamine.  The patient has no family history of heart disease or sudden cardiac death.  Temperature is 36.1 C (97 F) , blood pressure is 88/60 mm Hg, pulse is 105/min and regular, and respirations are 22/min.  Pulse oximetry is 91% on room air.  She is sitting upright in bed and appears uncomfortable.  Examination reveals diffuse crackles throughout the lung fields and dullness to percussion at the right lung base.  Apical impulse is palpated along the left anterior axillary line.  There is an extra low-pitched sound in early diastole, best heard with the bell of the stethoscope placed on the apex.  The patient's legs are cool and pulses are diminished.  There is 1+ bilateral peripheral edema.  Laboratory results are as follows: Pregnancy test is negative.  In addition to other appropriate therapy, the patient is given an intravenous medication that acts by primarily stimulating beta-1 adrenergic receptors.  Which of the following is the most likely mechanism by which this medication may improve her condition?

A) Decrease in heart rate
B) Decrease in left ventricular end-systolic volume
C) Decrease in myocardial oxygen demand
D) Increase in cardiac afterload
E) Increase in cardiac preload
F) Increase in left ventricular end-diastolic volume
G) Increase in pulmonary vascular resistance
H) Increase in systemic vascular resistance