I have an ascending aortic aneursym and have a bad cold with persistent cough. Can it cause problems with the aneursym?

Mostly not. increased chest pressure with cough usually does not affect the statue of thoracic aneurysm .only blood pressure systolic and diastolic could affect it.but the size and the location of the thoracic aneurysm will affect the chance of any leak or rupture.as long as your cough is not affecting your blood pressure it should not be a big problem.check with your PCP please.