To improve your heart health it is prudent to bring down your blood pressure.
Bringing down blood pressure will offload the heart and vascular system. Using medications and nutrients to bring down blood pressure as quickly as possible, then taper off the medications would be ideal.
There is a diet plan called the DASH diet that has been designed to help people lower their blood pressure. London nutritionist Steve Hines can coach you through implementing the DASH diet. It includes eating foods rich in protein, magnesium and antioxidants as well as reducing foods containing salt and sugar. There are some foods that acts like blood pressure drugs called ACE inhibitors, these foods include hydrolysed whey protein, pomegranate juice, celery and resveratrol in red wine.
Normative values for blood pressure would 120 over 80 but will fluctuate slightly depending on your activity and stress levels. The DASH diet in combination with nutrients and medication from your doctor can lower blood pressure.