I know both are generally safe, but is intravenous safer than general anesthesia? does intravenous cause complications if you have heart problems?

Both are the same: General anesthesia combines both intravenous and inhaled anesthetics. All anesthetics will have reversible effects on heart function. The physician anesthesiologist and other members of the anesthesia care team work jointly to ensure patient safety, especially patients with heart problems. Patients with known heart problems should discuss those issues with the Anesthesiologist before surgery