I had Gastric Bypass in 1997. I am now having heart issues. Can malabsorption cause heart problems years after the surgery?

Hello, thank you for sharing,
The best recommendation is to contact the doctor who perform the procedure, it's for your best if the doctor checks on you  and/or prescribe medication.
In addition to other criteria such as medical indications and safety, behavioral health assessments, and so forth I recommend that you go to your certified doctor so he can guide you and do the check up necessary to assist you.
My  Best Wishes

Yes, long-term malabsorption after gastric bypass can contribute to heart issues like A-Fib and palpitations. Deficiencies in essential nutrients such as iron, vitamin D, magnesium, B12, and potassium can have a significant impact on heart function over time.
Iron deficiency can lead to anemia, which reduces oxygen delivery to the heart and may trigger palpitations or worsen A-Fib. Vitamin D plays a role in heart health, and low levels have been associated with arrhythmias. Magnesium and potassium deficiencies, both common in gastric bypass patients, are particularly important for maintaining heart rhythm. A lack of magnesium, in particular, can directly contribute to A-Fib episodes. B12 deficiency affects nerve function and may contribute to irregular heartbeats.
Another potential factor is postprandial hypoglycemia, or reactive hypoglycemia, which is common after gastric bypass. This occurs when blood sugar drops after eating, triggering an adrenaline surge that can lead to palpitations and A-Fib. Additionally, irritation of the vagus nerve, which plays a role in both digestion and heart rhythm, may be contributing to your symptoms after meals. Small Intestinal Bacterial Overgrowth (SIBO), which is also common in gastric bypass patients, can cause inflammation that affects the nervous system and may worsen heart-related symptoms.
To address these concerns, you may want to have your doctor check your levels of iron, ferritin, vitamin D, magnesium (especially RBC magnesium), B12, and potassium. Monitoring your blood sugar after meals could help determine if hypoglycemia is playing a role. If deficiencies are found, replenishing electrolytes and essential nutrients may help stabilize your heart function. If digestive issues or bloating accompany your symptoms, testing for SIBO might also be beneficial.
Since your cardiologist may not be fully aware of the long-term malabsorption risks following gastric bypass, consulting a bariatric specialist or a functional medicine doctor could provide additional insight.