hello, dont worry its secondary infection/re-infection in periapical area of Root Canal
If bump is soft to feel then its abscess
.. if its hard to feel it can be a cystic lesion.. U need to undergo pathologic examination of the fluid taken from bump by FNAC.. repeat RCT will treat it but if it comes out to be cystic lesion in radiograph and FNAC..then u may need to go surgery (enucleation and curretage.) along with repeat rct..
no this bump will not affect ur heart directly if ur heart is healthy.. and u dont have prosthetic valves..
u can get temporary crown on ur lower tooth meanwhile prior to the surgery in both regions..
u can consult a good endodontist and oral-surgeon for upper tooth.. and a periodontist and prosthodontist for lower tooth..
U must keep on using antiseptic mouthwashes and local antibiotic
gels in ur inflammed gum region..
till the further treatment is done..