Effects of Nicorandil on Angina Symptoms in Patients With Coronary Slow Flow

Phase 4

Completed

Conditions: Slow Coronary Flow
Normal, or Near Normal Coronary Angiography
Stable Angina

Brief Summary: Slow coronary flow is an angiographically diagnosed phenomenon defined as delayed opacification of epicardial arteries in the absence of significant arterial narrowing and blockade. Endothelial dysfunction at the level of microarteries have been proposed as the main pathological mechanism in this regard. Available evidence suggest that standard anti-angina medications (e.g. nitroglycerin) that solely target large coronary trunks might not provide adequate symptomatic relief in patients with slow coronary flow phenomenon. It is hypothesized that anti-angina medications which exert vasodilatory effects in large coronary arteries as well as small dividing branches might be superior to nitroglycerin in amelioration of angina symptoms. The present randomized clinical trial was thus designed and conducted to compare the short-term efficacy of nicorandil (a dual-acting anti-angina medication with effects on both large and small coronary vessels) with nitroglycerin in a group of patients with slow coronary flow presented with frequent angina episodes.

Recruitment & Eligibility

Inclusion Criteria

on coronary angiographic studies, arterial narrowing did not exceed 50% in any of the three main coronary arteries; (
a delayed opacification in at least one of the main coronary arteries was documented. Delayed opacification was defines as corrected TIMI frame count > 23 fps

Exclusion Criteria

comorbid cardiovascular condition other than mild coronary atherosclerosis and coronary slow flow
refusal to participate
discontinuation of treatment
not returning for the follow up visit

Arm && Interventions

Group	Intervention	Description
Nitroglycerin	Nitroglycerin	sustained-release glyceryl trinitrate (6.4mg tablets, two times a day) + standard treatment (an anti-platelet agent, a beta-blocker, an angiotensin converting enzyme inhibitor, and a 3-hydroxy-3-methyl-glutaryl-CoA reductase inhibitor)
Nicorandil	Nicorandil	nicorandil (10mg tablets, two times a day) + standard treatment (an anti-platelet agent, a beta-blocker, an angiotensin converting enzyme inhibitor, and a 3-hydroxy-3-methyl-glutaryl-CoA reductase inhibitor)

Primary Outcome Measures

Name	Time	Method
Angina Episode Intensity	1 month	One month after treatment, patients were asked to determine the average intensity of chest pain in experienced episodes using a Likert-type scale of 0 to 10, where 0 indicated lowest intensity/no pain and 10 indicated the highest possible pain experienced.
Canadian Cardiovascular Society (CCS) Grading of Angina Pectoris	1 month	One month after treatment, patients were asked to describe the angina episode and based on their descriptions, the CCS class of chest pain was determined. Based on patient's description of the anginal episodes, angina severity was classified into one of CCS class I (angina only with prolonged demanding physical activity), Class II (Slight limitation, with angina only during vigorous physical activity), Class III (Symptoms with everyday living activities), or class IV (angina at rest).
Angina Episode Frequnecy	1 month	One month after treatment, patients were asked to determine the frequency of angina episodes in the preceding week.

Secondary Outcome Measures

Name	Time	Method
Side-effects	1 month	Patients were asked and underwent physical examination regarding the common and uncommon side effects attributed to anti-angina medications