Hello Priyanka

Your both options are very nice in their own way. Physiotherapy is a 5 year course in most of the college the teaches you anatomy, physiology etc. mostly the subjects taught in MBBS , so comparatively it is more tough than bsc cardiovascular tech.
BSc cardio. Tech. Is a 3 years course and it strictly needs msc for a good job , so basically both the courses requires time , both the courses have same background. You just have to figure out what you are good at , if you are comfortable in spending a lot of time in setting up your physiotherapist clinic and then start earning then surely go for BPT.
But if you want a stable and early job go for BSc.
Both the courses are good just depends on your interest.

All the best :)