Hello, welcome to the forum. Thanks for the question and we're sorry you are dealing with these heart conditions. Your question is a good one and we'll try to help. First though, it would be best if you ask your cardiologist this same question. That is always your best source of information as they know the particulars of you specifically rather than just general information.
So, first, dilated inferior vena cava. The inferior vena cava (IVC)is a large venous structure which delivers blood into the right atrium of the heart. It is usually <2cm in diameter. Anything that increases right atrial pressure will cause a subsequent increase in pressure inside the IVC resulting in dilation. However, if the pressure is reduced the IVC may return to its normal size. So, it could go back to normal if you reduce the pressure.
Leaky pulmonary valve is also called pulmonary valve regurgitation. This valve helps control the flow of blood passing from the right ventricle to the lungs. A leaky pulmonary valve allows blood to flow back into the heart chamber before it gets to the lungs for oxygen. https://www.heart.org/en/health-topics/heart-valve-problems-and-disease/heart-valve-problems-and-causes/problem-pulmonary-valve-regurgitation
These two things are likely interrelated. Please talk to your doctor.
Enlarged left side of the heart is called Left ventricular hypertrophy or LVH for short. Left ventricular hypertrophy is enlargement and thickening (hypertrophy) of the walls of your heart's main pumping chamber (left ventricle). The thickened heart wall loses elasticity, leading to increased pressure to allow the heart to fill its pumping chamber to send blood to the rest of the body. Eventually, the heart may fail to pump with as much force as needed. High blood pressure is a leading cause. Do you have high blood pressure? https://www.mayoclinic.org/diseases-conditions/left-ventricular-hypertrophy/symptoms-causes/syc-20374314
What prompted you to have testing done? What types of symptoms are you having? How is your doctor currently treating these things?