Congratulations on your new position!
When I was in school, I loved ICU nursing as well as anything cardiac. I got hired on a cardiac stepdown (progressive care) unit upon graduation. We received all of the cardiac patients coming in with chest pain, UA/NSTEMI (STEMIs went to ICU), CHF exacerbation, Afib with RVR/new onset Afib, hyper/hypokalemia, syncope along with a cornucopia's-worth of other diagnoses. Common problems we saw on my unit aside from what was mentioned above: pneumonia, COPD exacerbation, pulmonary embolism, DVT, CVA/TIA, renal failure (both acute and chronic), dizziness/weakness, altered mental status, ETOH intoxication, drug OD, seizures, acute GI bleed, anemia, thrombocytopenia, patients with coagulopathies (such as critically high PT/INR). Sometimes we would get med-surg overflow including post-op patients, usually for things like a lap-chole. We would get patients with pacemakers, including receiving patients after pacemaker placement, prep patients for stress tests and cardiac cath. We would also receive patients back from the cath lab, sometimes with the sheath still in place (sometimes not) so we had to be prepared to pull them.
With that said, I would brush up on those conditions. Brush up on your cardiac meds but realize you'll be giving a bunch of other meds, too. Brush up on your drips. Not all tele units are created equal but on my unit we would hang cardizem, dopamine, integrillin, heparin, nitro (titrate for chest pain only, not BP), octreotide, lasix and amiodorone. Some units may hang drips such as dobutamine and neosynephrine. So again, it depends.
Know your cardiac rhythms! And what to do. ACLS is great for that. Chances are you'll need your ACLS certification within a certain amount of months after your start date. ACLS won't teach you the different rhythms but instead will teach you how to treat them. In addition to ACLS, I would get a workbook on EKGs. ECG Workout by Jane Huff is a great one. ECG's Made Incredibly Easy! is also a good book but is lacking on the amount of practice strips. ECG Workout has tons of practice.
Don't be afraid to ask questions! And enjoy the ride. There will be some days where you'll literally hit the floor running...but let me tell you, I learned so much working on a progressive care unit. And you will, too.
Finally, get yourself a good brain sheet. Do a search here on AN and you'll find a lot of examples, or create your own. A good brain sheet is key to helping you stay organized during your shift.