Condition category
Circulatory System
Date applied
Date assigned
Last edited
Retrospectively registered
Overall trial status
Recruitment status
No longer recruiting

Plain English Summary

Not provided at time of registration

Trial website

Contact information



Primary contact

Dr Peter Schofield


Contact details

Papworth Hospital NHS Foundation Trust
Papworth Everared
CB23 3RE
United Kingdom
+44 (0)1480 830541

Additional identifiers

EudraCT number number

Protocol/serial number

Version 2.2 dated 5 January 2004

Study information

Scientific title

An open label, single-centre, randomized trial of spinal cord stimulation vs percutaneous myocardial laser revascularization in patients with refractory angina pectoris: the SPiRiT trial



Study hypothesis

Refractory angina pectoris leads to significant morbidity. There is an increasing group of patients with 'refractory angina pectoris' who are unsuitable for conventional revascularization by coronary artery bypass surgery or percutaneous intervention. This patient group often have significant disability, with limiting symptoms, multiple medications, and frequent hospital admissions.

Treatment options include percutaneous myocardial laser revascularization (PMR) and spinal cord stimulation (SCS). The primary objective of this study was to compare the effect of SCS vs PMR on treadmill exercise time on a modified Bruce protocol over a period of 12 months.

Ethics approval

Approval was obtained from the Huntingdon Local Research Ethics Committee, UK, prior to study commencement, on 15 August 2000 (ref: H00/557)

Study design

Prospective, open, parallel, single-centre, randomised controlled trial.

Primary study design


Secondary study design

Randomised controlled trial

Trial setting

Not specified

Trial type


Patient information sheet


Chronic angina pectoris


Trial patients were randomised to either Spinal Cord Stimulation System implant (SCS) or Percutaneous Myocardial Laser Revascularisation (PMR).

The Spinal Cord Stimulation System used for this trial was a Medtronic fully implantable SCS systems. Either Itrel 3 or Synergy implantable generators were used. The spinal cord stimulation lead was chosen by the investigator from any Medtronic commercially available lead approved for use in refractory angina pectoris. The implant was performed according to the instructions in the technical manuals accompanying the devices. The lead was placed such that adequate/optimal paraesthesia was obtained in the area of angina pain. When adequate paraesthesia coverage was obtained the physician went on to permanent implant of the pulse generator. Proper patient education both pre and post implant of the device is essential. The investigator was responsible for adequately and regularly checking the integrity of the system at 3 months, 12 months and then annually. The stimulator should be used prophylactically by the patient for a minimum of 3 hours per day (for example: 3 times per day for a duration of 1 hour each). However, there is no upper limit and the patient may use the device as much as needed. Parameters for this stimulation vary from patient to patient. Therefore, the physician and patient need to work together to establish an effective and tolerable level. The stimulator should also be used at time of anginal attack to treat the pain. A higher level of stimulation may be used for this acute treatment. The maximum tolerable amplitude should be set for such use. However, it is necessary to assure that this level is not uncomfortable or painful.

For this trial any commercially available Percutaneous Myocardial Revascularisation could be used. An optical fibre is inserted via the femoral artery under local anaesthesia and passed up into the left ventricle. Energy from a Ho:YAG laser is applied to the endocardial surface of the myocardium to vaporise the myocardial tissue and create channels from the endocardial surface into the myocardium. The co-axial system allows the laser to be manipulated in 3 planes giving access to the whole of the left ventricle. The laser position is monitored by fluoroscopy in orthogonal views. Once the position of the laser has been checked in both views, the laser is fired. Two bursts of the laser are used to create a channel 4-6 mm deep, in the myocardium, except in the apex where only one burst is used. The position is marked in both views on acetate sheets attached to the fluoroscopy monitors. Laser channels are created at a minimum of 1 cm apart, and are placed to cover the target region. Typically 10-15 channels are being made.

Intervention type



Not Specified

Drug names

Primary outcome measures

Total exercise time on a modified Bruce protocol (ETT) at 12 months after SCS compared with PMR. In this study, all tests were terminated by the subject. Both SCS and PMR aim to reduce the frequency and severity of angina, and exercise tolerance is a comparatively objective method of measuring angina-free functional capacity.

Secondary outcome measures

1. Time to patient-reported angina during exercise test
2. Angina class as measured by the Canadian Cardiovascular Score angina scale
3. Morbidity and mortality
4. Safety profiles of each therapy
5. Health-related quality of life was assessed using questionnaires administered at 3, 12, 24 and 36 month follow-up (disease-specific Seattle Angina Questionnaire, the generic Short Form 36 health survey , and EuroQoL questionnaires)

Overall trial start date


Overall trial end date


Reason abandoned


Participant inclusion criteria

1. Patient with limiting angina (Canadian Cardiovascular Society [CCS] III or IV) despite maximally tolerated medical therapy
2. Documented coronary artery disease (within the last 9 months prior to baseline), which is
unsuitable for conventional revascularisation techniques
3. Patient has documented reversible ischaemia on nuclear scan (Tc-99 sestamibi)
4. Patient is limited in daily activities, primarily exercise capability, by their anginal pain
5. Age 18 or older
6. Patient must understand the therapy and give informed consent
7. Patient must be available for appropriate follow-up times for length of study
8. Non-pregnant women (only women who are post menopausal, surgically sterile or those of
child bearing potential who are using an acceptable method of contraception) as safety for
use of SCS during pregnancy or delivery has not been established. Acceptable methods of
contraception include the following:
a. Barrier type devices (e.g. female condom, diaphragm and contraceptive sponge) used only in combination with a spermicide
b. Intrauterine devices (IDUs)
c. Oral contraceptive agent
d. Depro-ProveraTM (medroxyprogesterone acetate)
e. Levonorgestrel implants
f. Naturally sterile (amenorrheic for at least 1 year) in patients over 50
Note: Abstinence, the rhythm method or contraception by the partner alone are NOT acceptable methods of contraception

Participant type


Age group




Target number of participants


Participant exclusion criteria

1. Patient who is not a candidate for surgical implantation of the spinal cord stimulation system,
and/or not a candidate for a PMR procedure and/or unable to use the SCS device appropriately for treatment
2. Patient who has had one or more major cardiac events within the last 2 months
3. Patient with a myocardial wall thickness <8 mm in the ischaemic area to be treated as verified
by echocardiography
4. Patient with extensive peripheral vascular disease that precludes vascular access required for
5. Patient on intravenous therapy to control their symptoms
6. Patient who is unlikely to survive for more than 12 months due to non cardiac condition e.g.
7. Patient who has other diseases that are considered of greater clinical significance than the
angina pectoris (e.g. inadequately controlled diabetes mellitus, heart failure) that would impact
the ability of the clinician to adequately assess the incremental effects of the trial treatment
8. Patient with ejection fraction of less than 30% as verified by echocardiography
9. Patient with cause of angina other than coronary artery disease (e.g. syndrome "X" patient)
10. Patient who is unable to perform treadmill exercise test per protocol
11. Patient who was previously enrolled in this study, or is currently in another clinical study, which will interfere with this protocol
12. Patient who has had spinal cord stimulation (SCS) therapy, a transmyocardial laser revascularization (TMLR) or PMR procedure in the past
13. Patient with an implanted pacemaker or defibrillator
14. Patient who has medical conditions which may require Magnetic Resonance Imaging (MRI)
15. Patient with a history of dementia or other persisting mental disorders significantly interfering
with ability to cooperate or comply with the requirements of the study or comprehend informed
16. Patient with history of alcohol or drug abuse

Recruitment start date


Recruitment end date



Countries of recruitment

United Kingdom

Trial participating centre

Papworth Hospital NHS Foundation Trust
CB23 3RE
United Kingdom

Sponsor information


Medtronic Sàrl (Switzerland)

Sponsor details

Route du molliau

Sponsor type




Funder type


Funder name

This study was sponsored by Medtronic SA, who were responsible for funding of the trial related investigations such as perfusion scans and treadmill tests, research staff for data collection and travelling expenses for the subjects. The sponsor had no role in study design, data collection and interpretation, or in the decision to submit the above report for publication.

Alternative name(s)

Funding Body Type

Funding Body Subtype


Results and Publications

Publication and dissemination plan

Not provided at time of registration

Intention to publish date

Participant level data

Not provided at time of registration

Results - basic reporting

Publication summary

Results in

Publication citations

  1. Results

    McNab D, Khan SN, Sharples LD, Ryan JY, Freeman C, Caine N, Tait S, Hardy I, Schofield PM, An open label, single-centre, randomized trial of spinal cord stimulation vs. percutaneous myocardial laser revascularization in patients with refractory angina pectoris: the SPiRiT trial., Eur. Heart J., 2006, 27, 9, 1048-1053, doi: 10.1093/eurheartj/ehi827.

Additional files

Editorial Notes