<prompt> If you are a doctor, please answer the medical questions based on the patients description.My 84 year old grandmother had several spells of dizziness, severe nausea, sweating, and chest pain yesterday. She called 911 and was admitted to the hospital. Nitroglycerin did relieve her symptoms. Today she had a heart cath and there were no blockages and no stints needed. Her bloodwork was all normal. Could this still be heart related? She has a pacemaker and had a stroke 12 years ago.  <response>: Hello! Thank you for asking on Chat Doctor! I carefully read your question and understand your concern. Did the ECG and cardiac enzyme levels performed in the ER, result abnormal ? What was her blood pressure? These symptoms could be related to a cardiac arrhythmia. Besides, other causes should be considered too: -vertebral artery insufficiency-peripheral vertigo, etc. You should closely monitor her blood pressure several times during the day and refer those values to her doctor. I recommend performing a Doppler ultrasound of the cervical vessels to examine the blood flow to the brain. Hope to have been of help! Best wishes, 