Explore This Procedure


The Massachusetts General Hospital Corrigan Minehan Heart Center offers a highly advanced innovative approach to treat patients with chronic total occlusion, called chronic total occlusion percutaneous coronary intervention (CTO PCI). CTO PCI is a minimally invasive technique used to treat patients with chronic total occlusion (CTO), or complete blockages, of the coronary arteries.

What Is CTO PCI?

CTOs are blockages that have typically been present for more than three months. These blockages are a result of severe build-up of fatty deposits or plaque within the arteries (atherosclerosis) and are one of the complications from coronary artery disease (CAD). CAD occurs when the artery or arteries that supply blood to the heart become narrowed or blocked because of atherosclerosis. When the heart does not receive enough blood, a person may have chest pain (angina), shortness of breath or a heart attack. These symptoms occur with exertion and sometimes at rest. 

Individuals with CTOs may experience the following symptoms:

  • Chest pain, pressure or tightness (angina pectoris)
  • Shortness of breath
  • Dizziness
  • Fatigue
  • Nausea
  • Pain in the upper body and arm
  • Rapid or irregular heartbeat

Treatment options for CTO have traditionally been limited due to the complexity of opening up completely blocked arteries using catheter-based techniques. Historically, physicians often recommended coronary artery bypass grafting (CABG), or open-heart surgery, as the only option for treating these blockages. During this surgery, a vein or artery from another part of the body is taken to create a new route to the coronary artery, bypassing the blocked area and allowing a path for blood flow. Some patients, however, may not be candidates for CABG surgery due to high surgical risk. In other cases, some patients may not require CABG and could benefit from stenting using CTO PCI techniques. During a stenting procedure, a small mesh tube is placed in narrow or blocked arteries to widen and support the walls of the arteries and restore blood flow.

New technologies and advanced training have enabled Mass General to offer minimally invasive methods for treating CTOs with success rates approaching nearly 90%.

Method: How Is CTO PCI Performed?

CTO PCI is a procedure performed by experienced cardiac interventionalists with specialized training in advanced methods to treat CTO blockages; at present, only 1-2% of cardiac interventionalists in the U.S. can perform the full range of CTO PCI. The procedures vary in duration from two to five hours depending on the complexity of the blockages. All patients are admitted to the hospital overnight after the procedure in order to be monitored.

Mass General is one of the few centers in the U.S. to use a combination of antegrade (forward-moving including dissection/re-entry) and retrograde (backward-moving) approaches to access the blockage. When a blockage occurs, new blood vessels known as collateral blood vessels are formed around the blockage to help with blood flow. Using advanced guide wires, our physicians insert a catheter into these collateral vessels, entering the blocked artery from multiple sides. Using a technique called balloon angioplasty, a small uninflated balloon is placed at the tip of the catheter and inflated while in the artery. This approach, along with stents, is used to create a wider opening in the arteries to restore blood flow.

How Safe Is the Procedure?

The procedure has a slightly elevated risk of kidney damage due to intravenous contrast use and bleeding at the entry site into arteries in the groin. However, most other risks are similar to those seen for more routine angioplasty and can include:

The procedure has a slightly elevated risk of kidney damage due to intravenous contrast use and bleeding at the entry site into arteries in the groin. However, most other risks are similar to those seen for more routine angioplasty and can include:

  • Bleeding at the puncture site
  • Damage to the blood vessel at the puncture site
  • Sudden closure of the coronary artery
  • Small tear in the inner lining of the artery
  • Heart attack

Commitment to Expertise and Excellence

CTO PCI is a complex procedure that requires expert care from highly experienced physicians. The CTO PCI team at Mass General has received specialty training in the procedure, studying under a small group of internationally recognized pioneers in the field. 

The team comprises clinicians who are leaders within the field of CAD. Our physicians will work with you, your care team and other experts at the Mass General Corrigan Minehan Heart Center to determine the best course of treatment for your chronic total occlusion. We conduct a thorough evaluation in concert with your primary care team to develop a comprehensive treatment plan that meets your individual needs.

Mass General is consistently ranked among the best hospitals in the country by U.S. News & World Report. Our ranking is based on our quality of care, patient safety and reputation in more than a dozen different specialties. We work to ensure that you receive the best care at all points during your visit. Our patients can benefit from shared expertise, leading research and our commitment to quality and excellence.

Patience Experience

Patients must be eligible to undergo CTO PCI. The CTO clinical team will perform a careful review of your history, clinical data and previous assessments of your cardiac and medical condition to determine whether or not CTO PCI is a recommended option. We work in collaboration with your primary care, cardiology and medical teams.

If you are scheduled for a CTO PCI, please follow the below instructions to prepare for your procedure:

  • Discuss medications, allergies and any other issues with your doctor prior to the procedure
  • Continue to take medications on your prescribed schedule. Medications such as Coumadin®, other anticoagulants, diuretics, insulin and oral diabetic medication will require individual review by your physician
  • Do not eat food or drink (except a few sips of water with medication) after midnight

The afternoon prior to your procedure, a nurse from the catheterization lab will contact you to review these instructions and let you know when to arrive at the lab. Please use this opportunity to address any questions or concerns about your procedure.

CTO PCI Procedure: Recovery and Follow-up

At the start of the procedure, patients receive sedation as in usual heart catheterization procedures. During the procedure, two catheters are placed in arteries (leg or wrist) to allow the ability to go forwards or backwards as needed. Following completion of the procedure, which takes approximately 3-4 hours, the catheters are removed.

First-time success rates approach 85-90%. In some cases, partial success occurs, and patients will be recommended to have a re-attempt 6-8 weeks later.

Most patients are discharged the next day after review of their catheter sites and blood work. Patients who undergo CTO PCI often have an improvement of their symptoms within days to weeks. Some patients notice an improvement even before discharge. Additionally, studies have shown that patients who have had CTO PCI have seen an improvement in their quality of life, including:

  • Reduced chest pain (angina)
  • Reduced shortness of breath
  • Increase in physical activity
  • Decrease in feelings of depression
  • Higher levels of energy

The Mass General CTO PCI team will arrange for post-procedure follow-up.

Patient Resources

Mass General is dedicated to ensuring that people understand their health care choices and have the necessary information to make decisions affecting their health and wellbeing. The related support and wellness information listed below can play a role in treatment options.

Patient Guide to Cardiac Surgery
Patient Guide to Cardiac Surgery

Patient Guide to Cardiac Surgery

What to expect before, during and after your surgery at the Corrigan Minehan Heart Center.

FAQs: Cardiac Anesthesia
FAQs: Cardiac Anesthesia

FAQs: Cardiac Anesthesia

A guide of what to expect before, during and after cardiac anesthesia.

Family Guide to Cardiac Surgery
Family Guide to Cardiac Surgery

Family Guide to Cardiac Surgery

Support and guidance during a family member's open-heart surgery or transplantation.