<s>[INST] I am always tired, exhausted. I can t walk up stairs without getting out of breath and feeling like I m about to pass out. (I ve been diagnosed with orthostatic hypotension??.) I feel like everything drains out of me when I walk, even slowly, upstairs. Even if it s only a few steps. I m breathing hard, hr goes way up and I feel like my blood pressure plummets.usually can t stand up straight until it goes away and feel like my legs are going to give out on me. Also if I squat down everything starts to go black when I stand back up. All my labs are normal and cardiac said my heart is fine altho it did show some tachy some brady and pvc s. My EKG showed a short PR. What is wrong with me?? [/INST] Thanks for your question on Chat Doctor. I can understand your situation and problem. In my opinion you should consult cardiologist and get done1. 2d echo2. Stress test3. Holder monitoring (24 hour recording of ECG)4. Coronary angiography SOS (if required). You are having irregular heartbeat with orthostatic hypotension, this suggests possibility of arrhythmia or coronary artery disease (CAD). So better to get done above investigations first and diagnose yourself and start appropriate treatment. So consult cardiologist and discuss all these. </s>