Facilitating Catheter Guidance to Optimal Site for VT Ablation
Facilitating Catheter Guidance to Optimal Site for VT Ablation
Each year in the UK, approximately 150,000 people have a heart attack when the blood supply
 to their heart is compromised. As a result, affected regions of the heart can become diseased
 and scarred. In a healthy person, electrical waves propagate across the heart in a regulated
 pattern which triggers contraction to pump blood around the body. The scar tissue that forms
 as a result of a heart attack can disrupt the propagation of the electrical waves. If
 significant disruptions occur, blood cannot be pumped out of the body effectively, leading to
 sudden death.

 Ablation therapy aims to eliminate areas of diseased tissue that cause disruption to the
 heart rhythm, by applying radiofrequency using catheters inserted into the heart. The most
 accurate techniques used to locate the region to ablate require the induction of dangerous
 heart rhythms, which are only inducible in about 65% of people.

 Pace mapping is a technique used to locate regions to ablate, which can be performed during
 normal heart rhythm. ECG data, which records electrical signals from the heart, is collected
 when the patient has an abnormal heart rhythm. From this template ECG, a clinician can tell
 the approximate location of the diseased tissue. A catheter is directed to that location, the
 heart stimulated, and another ECG, called the paced ECG is recorded. If the paced ECG matches
 the template ECG, it is assumed that the heart was paced in the location that requires
 ablation.

 Current ablation techniques are difficult, time consuming, and inaccurate. As a result, the
 procedure may work in only half of all patients, and result in unnecessary damage to healthy
 tissue, leading to later impairment of heart function.

 The CPS project's overall goal is to increase the success rates of ablation therapy by
 improving the accuracy and efficiency of locating the optimal region of tissue to eliminate
 during the pace mapping procedure. Increasing ablation therapy success rates will mean that
 patients will be unlikely to suffer from future heart rhythm disorders as a result of their
 heart attack, increasing the life expectancy of heart attack patients. Excess damage caused
 to the heart as a result of unnecessary ablation lesions will be limited, decreasing the
 likelihood of future complications. In addition, dangerous heart rhythms do not need to be
 induced in the patient, significantly decreasing the risk of death during the treatment.
Inclusion Criteria:

 -  post-myocardial infarction ventricular tachycardia diagnosis

 -  scheduled to undergo radiofrequency catheter ablation as either emergency or elective
 case

 Exclusion Criteria:

 -  Unable to perform pace mapping during ablation procedure

 -  Unable to terminate VT thus unable to provide data regarding successful ablation
 lesion sites

 -  Intracardiac thrombus