What does it mean if an echo shows you have a mildly dilated right vetricle and mild pulmonary hypertension?

I am a 25 year old female who has been tachycardic for some time, i started sufferng from palpatations so was referred to a cardiologist. I had a 24 hour tape whic shows my heart rate is normal rythem but went up to 158 bpm (it didn't go below 99). the cardiologst said he didn't think t was a cardiac problem and suggested i lose weight and give up smoking he sent me for an echo just to be sure this shows i have a mildly dilated right ventricle 3.1 and mild pulmonary hypertension. what does ths mean?