Blood Markers for Inflammation and Coronary Artery Vasoreactivity Testing in Patients With Chest Pain and Normal Coronary Arteries

Summary

The investigators are hoping to discover the cause of chest pain in patients with a normal coronary arteriogram. For patients with chest pain coronary angiography is the standard method by which the blood vessels of the heart can be visualized and any narrowing can be assessed. In some cases the investigators find totally normal coronary blood vessels or only minor disease. Such a finding is associated with an excellent long term prognosis. However, as a large proportion of patients with normal coronary arteries or mild coronary narrowings often continue to experience recurrent chest pains the investigators are interested in understanding the mechanisms responsible for this. The investigators hypothesise that in many cases, coronary artery spasms are responsible for the recurrent chest pains. These spasms usually respond to treatment with drugs known as vasodilators. The acetylcholine test (ACH-test) has been recommended by the European Society of Cardiology and the American College of Cardiology as a diagnostic test. This test can reveal whether the coronary blood vessels have a tendency to go into spasm. The investigators plan in this study to carry out the test in patients who have chest pains suggestive of coronary narrowings but are found to have normal or only mildly narrowed coronary arteries on angiography. A positive test -indicating a tendency for spasm- may help guiding therapy with vasodilators, which are often very effective to prevent coronary spasms. The investigators would also like to take blood samples during the test (before and after) from every patient to measure blood markers and see if there is a relation between these markers and the result of the ACH-test.

Conditions

• Endothelial Dysfunction
• Atherosclerosis
• Inflammation
• Myocardial Ischemia

Interventions

DRUG

Acetylcholine

Incremental doses of 2, 20 and 100 µg of ACH will be injected into the left coronary artery (LCA) via the diagnostic catheter for 3 minutes each. After that 80 µg of ACH will be injected into the right coronary artery. Coronary angiography will be performed after each 3 minute dose period. After the test or when intolerable chest pain due to coronary spasm occurs, 0.2 mg of glyceryltrinitrate will be injected into each vessel. During the test, heart rate, blood pressure and ECG will be monitored continuously.

DRUG

Adenosine

Coronary blood flow velocity measurements will be performed in the mid segment of the left anterior descending artery with a 0.014-in intracoronary Doppler guidewire connected to the corresponding interface. Measurements will be obtained after the administration of nitroglycerin, at baseline and during maximal hyperaemia. Sustained intravenous administration of adenosine - an arteriolar vasodilator- will be used to induce maximal hyperaemia (140-180µg/kg/min).

Sponsors & Collaborators

• St George's Healthcare NHS Trust

  lead OTHER

Principal Investigators

• Juan C Kaski, MD · Department of Cardiology, St George's Healthcare NHS Trust

Study Design

Allocation

NON_RANDOMIZED

Purpose

DIAGNOSTIC

Masking

NONE

Model

PARALLEL

Eligibility

Min Age

35 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2011-01-31

Primary Completion

2011-04-30

Completion

2011-12-31

Countries

• United Kingdom

Study Locations