Invasive/Non-interventional and Interventional cards are in fact different.
When asking this question, whether one is considering Academic or Private practice is an important distinction.
Private Practice:
Non-invasive: inpatient consults, CCU, echo (some do TEE), treadmill stress testing, nuclear cardiology, +/- CT angiography, outpatient clinic. When on-call, if a cath is required will call in the interventionalist. Does not take STEMI call.
Invasive non-interventional: everything that non-invasive does, but can do right heart catheterization with complex hemodynamic assessment, TEE, coronary/bypass angiography, LV angiography/Left heart catheterization, pericardiocentesis, intra-aortic balloon pump, permanent pacemaker implant (if skill was acquired as a fellow), ICD implantation (typically not BiV). When on call, if a cath is required, they do it. If a stent is called for, the interventionalist comes in. They can do intra-aortic balloon pumps and can do a pericardiocentesis if needed. In some places, they DO take STEMI call. They will shoot the diagnostic part prior to the interventionalists arrival. Furthermore, when on call, if a patient with unstable angina or NSTEMI requires a cath, the invasive non-interventionalist will do the diagnostic procedure, and only call the interventionalist if stenting is required.
Interventional: typically does not do TEE, many do not read nucs, still read echo, have a clinic, inpatient consults, treadmill stress testing, coronary stenting, +/- peripherals, IABP, pericardiocentesis. They typically do not do permanent pacemaker or ICD implants. Takes STEMI call. Some do balloon valvuloplasty, ASD closure, alcohol septal ablation, and now TAVI.
In the majority of Academic Institutions, though certainly not all (A lot of VAs for example have non-interventionalists doing diagnostic caths and RHCs), all cardiac catheterizations are done by Interventionalists, and all EP procedures are done by electrophysiologists.
In private practice, the interventionalists don't just sit and wait to do caths. They have their own clinics, and function as general cardiologists as their non-interventional colleagues. In fact, some EP physicians must also take general cardiology call.
So, those who are arguing that there is no difference between an invasive cardiologist and an interventionalist are simply misinformed. As someone said before, most cardiac catheterizations do not end in stenting. Cardiac catheterization is a broad term that encompasses right heart catheterization, coronary/bypass angiography, and left heart catheterization (generally entering the LV via a retrograde approach through the aortic valve to measure LVEDP, determine LV/AO gradients in AS, and to perform LV angiography to measure LV volumes and ejection fraction). Perhaps some of the differences can be confusing to non-cardiologists, but there are many indications for cardiac catheterization that have nothing to do with coronary stenting.
As a reflection of the above stated distinctions, when one is applying for cardiology jobs following fellowship (mostly in private practice), he or she will notice that jobs are offered for non-invasive, invasive non-interventional, and interventional. They are in fact different.
