Same reference-panel format: what it is → why it's done → what to expect. Each entry includes a note on preparing for it — for after-procedure care following a catheterization, biopsy, or CardioMEMS implant, see Care After Your Catheterization, Biopsy & CardioMEMS Procedure.
Right Heart Catheterization
A thin tube (catheter) is threaded through a vein (usually in the neck or groin) into the right side of the heart and lungs to directly measure internal heart pressures and how well the heart is pumping. It's considered the most accurate way to diagnose and characterize heart failure and pulmonary hypertension — more precise than imaging alone, since it measures actual pressures rather than estimating them.
What to expect: your access point is usually a vein in your neck (internal jugular) or groin (femoral) — the specific site your team chooses depends on your anatomy and their usual approach. You'll be awake for the procedure with local numbing medication at the access site plus a mild sedative to help you relax; you're not put under general anesthesia. The catheter itself is thin and flexible, and most people describe feeling pressure at the access point rather than pain as it's guided toward the heart under X-ray guidance. The whole visit typically runs 1–2 hours including preparation and recovery, with the actual catheter time usually well under 30 minutes.
Preparing for it: usually done as an outpatient or short-stay procedure. Expect instructions to fast for several hours beforehand, confirmation of which medications (especially blood thinners) to hold and for how long, and to arrange a ride home since you won't be able to drive afterward.
Left Heart Catheterization
A catheter is threaded through an artery (usually in the wrist or groin) into the heart's left side and coronary arteries, with dye injected to directly visualize blockages. This is the definitive test for diagnosing coronary artery disease and is often combined with treatment (see PCI, below) in the same procedure if a blockage is found.
What to expect: access is most often through your wrist (radial artery) — increasingly the preferred site since it's more comfortable and has a lower bleeding-complication rate — or your groin (femoral artery) when wrist access isn't suitable. You'll be awake, with local numbing at the access site and a mild sedative; general anesthesia isn't used. As the catheter is guided toward your heart under X-ray imaging and contrast dye is injected, you may feel a brief warm flushing sensation — this is expected and passes quickly. Most people are on the table for 30–60 minutes, with several more hours of monitoring and recovery afterward, longer if a same-visit intervention is needed.
Preparing for it: similar to right heart catheterization — fasting beforehand, specific guidance on which medications to hold, a kidney-function check beforehand (since contrast dye is used), and a ride home arranged in advance. Ask your team whether to expect a same-day discharge or a short observation stay, since it depends on what's found.
Endomyocardial Biopsy
A small catheter retrieves tiny tissue samples from inside the heart, most often used to monitor for organ rejection after heart transplant (see Life After Transplant and Monitoring, Procedures & Labs After Transplant for how this fits into your overall post-transplant care), or occasionally to diagnose specific cardiomyopathies (like certain infiltrative or inflammatory conditions) when other testing is inconclusive.
What to expect: access is almost always through a vein in your neck (internal jugular), less commonly your groin. With the access site numbed and light sedation on board, a thin catheter called a bioptome is guided into the right side of your heart, where its jaws take several small tissue samples — you won't feel the actual sampling itself, since the heart muscle has no pain fibers for this kind of contact. Most routine surveillance biopsies are brief, often well under an hour of actual procedure time, and many recipients describe it as more tedious than painful once the access site is numbed.
Preparing for it: for routine post-transplant surveillance biopsies, these are typically brief, well-practiced outpatient visits with fasting instructions similar to a heart catheterization; your transplant team will tell you which of your immunosuppression doses, if any, to adjust around the appointment.
Swan-Ganz (Pulmonary Artery) Catheter
A specialized catheter left in place, usually in an ICU setting, to continuously monitor heart pressures and function in real time — commonly used in cardiogenic shock or complex heart failure management to guide moment-to-moment treatment decisions.
Preparing for it: this is placed urgently or emergently as part of inpatient, often ICU-level care — there typically isn't elective preparation involved, since the clinical situation itself is what prompts it.
Intra-Aortic Balloon Pump (IABP)
A temporary support device: a balloon on a catheter sits in the aorta and inflates/deflates in rhythm with your heartbeat, reducing the heart's workload and improving blood flow to the coronary arteries. Used short-term in cardiogenic shock or high-risk procedures.
Preparing for it: usually placed urgently in the hospital, sometimes electively immediately before a planned high-risk procedure — your care team will explain the specific plan and timeline for your situation, since there is little standalone "preparation" outside that context.
Impella Device
A small temporary mechanical pump inserted through an artery directly into the heart, actively pumping blood to take over some of the heart's work. Used in cardiogenic shock or to support the heart during high-risk procedures — generally more powerful support than an IABP, for a limited time.
Preparing for it: as with IABP, this is placed either urgently or immediately ahead of a planned high-risk procedure it's supporting — preparation is folded into that procedure's own planning rather than being a separate step.
ECMO (Extracorporeal Membrane Oxygenation)
The most intensive level of temporary life support: blood is pumped outside the body through a machine that adds oxygen and removes carbon dioxide, essentially taking over heart and/or lung function for days to a couple of weeks while the underlying problem is treated or a longer-term plan (recovery, durable device, or transplant) is decided.
Preparing for it: always an emergent, inpatient decision made by your critical care team in a life-threatening situation — there is no elective preparation, and family members are typically the ones receiving explanation and consent discussions in real time.
CardioMEMS
A tiny wireless sensor implanted in the pulmonary artery that transmits daily pressure readings to your care team from home — allowing fluid buildup to be caught and treated before it causes symptoms or a hospitalization, rather than reacting after the fact.
What to expect: access matches right heart catheterization — a vein, usually in your groin — with local numbing and light sedation while you stay awake. The sensor is guided into a branch of your pulmonary artery and released, where it stays permanently; you won't feel it once it's in place. The implant itself usually takes 30–45 minutes, with a longer total visit for preparation and recovery.
Preparing for it: a scheduled outpatient procedure similar in preparation to a right heart catheterization — fasting beforehand, guidance on which medications (particularly blood thinners) to hold, and a ride home arranged. Your team will also set up the home monitoring equipment and walk you through it before or shortly after the implant.
Pacemakers & Defibrillators (including CRT-D)
- Pacemaker — a small device that paces the heart when it's beating too slowly
- Defibrillator (ICD) — monitors for dangerous, potentially fatal fast rhythms and delivers a shock to correct them if needed
- CRT-D — a combined device that both re-synchronizes the timing of the heart's two pumping chambers (helping a weakened heart pump more efficiently) and provides defibrillator protection — used in specific patients with HFrEF (heart with weak contraction) and particular electrical patterns on their ECG
What to expect: the device (a generator roughly the size of a small stopwatch) is placed just under the skin near your collarbone, usually on your non-dominant side, with its leads (thin wires) threaded through a nearby vein into your heart chambers. You'll typically have local anesthesia at the incision site plus conscious sedation (medication that keeps you relaxed and drowsy but breathing on your own) — general anesthesia isn't usually needed. The incision itself is small, roughly 2 inches, and most people describe pressure or tugging sensations during lead placement rather than sharp pain. The procedure itself generally takes 1–2 hours, followed by several hours of monitoring before you're discharged the same day or after one overnight stay.
Preparing for it: typically a scheduled outpatient or short-stay procedure — fasting beforehand, specific guidance on holding blood thinners, pre-procedure bloodwork and imaging your team already has on file, and a ride home arranged, since you'll be discharged the same day or after a brief overnight stay depending on the device and your situation.
PCI (Percutaneous Coronary Intervention) — Angioplasty & Stents
When a blockage is found during left heart catheterization, a small balloon is used to open the artery, and a stent (a small mesh tube) is typically left in place to hold it open. Done through the same wrist or groin access as the diagnostic catheterization, often in one combined procedure.
What to expect: the access site and anesthesia approach match left heart catheterization — usually your wrist, with local numbing and light sedation while you stay awake. Once the blockage is located, a guidewire crosses it, a balloon-tipped catheter is inflated to open the artery, and the stent is expanded into place against the artery wall to hold it open — you may feel brief chest pressure or discomfort as the balloon inflates, which resolves quickly once it's deflated. Total procedure time is usually 30–90 minutes depending on how many blockages are treated, with several hours of monitoring afterward.
Preparing for it: when planned in advance (rather than added on during a diagnostic catheterization that finds a blockage), preparation matches left heart catheterization — fasting, medication guidance, and a ride home. If it's combined with your diagnostic catheterization in the same visit, you'll typically have been prepared for that possibility ahead of time.
CABG (Coronary Artery Bypass Graft) — "Bypass Surgery"
Open-heart surgery that reroutes blood flow around blocked coronary arteries using a healthy blood vessel taken from elsewhere in your body (commonly the chest wall or leg). Generally reserved for more extensive or complex blockages than PCI can address well, particularly multi-vessel disease or blockages in certain critical locations.
What to expect: this is done under general anesthesia — you're fully asleep and on a breathing machine throughout. Access is a sternotomy, an incision through the breastbone to reach the heart directly, and most CABG surgeries use a heart-lung bypass machine to temporarily take over your circulation while your surgeon works. Grafting vessels — commonly an artery from inside your chest wall and/or a vein from your leg — are attached to reroute blood flow around the blockages. The operation itself typically takes 3–6 hours depending on how many vessels need bypassing, followed by an ICU stay for the first day or two. (See Open Heart Surgery: What to Expect for the fuller recovery picture, including sternal precautions and the general hospital-stay timeline.)
Preparing for it: as major surgery, this involves the most extensive preparation of anything on this page — pre-operative testing (bloodwork, imaging, sometimes dental clearance to reduce infection risk), a detailed medication review with specific instructions on what to hold and when, and planning for a hospital stay of about a week followed by a structured recovery. Your surgical team will walk you through a specific pre-op checklist well before the scheduled date.