Active clinical trials for "Coronary Vasospasm"

EXAMINE-CAD-DZHK22 is a prospective, randomized, double-blind, placebo-controlled, crossover trial investigating the efficacy of beta blocker (bisoprolol) and calcium channel blocker (diltiazem) therapy in symptomatic patients with non-obstructed coronary arteries according to coronary physiological testing results.

Rationale: Up to 40% of patients undergoing a coronary angiogram for symptoms/signs of ischemia do not have obstructive coronary artery disease (CAD). In about half of them the mechanism underlying cardiac ischemia is coronary microvascular dysfunction (CMD). In CMD, myocardial ischemia is caused by impaired endothelial and/or non-endothelial coronary vasoreactivity resulting in the coronary microvasculature not dilating properly or becoming vasospastic. Recently published diagnostic criteria state that to confirm the diagnosis, CMD patients should either have an impaired coronary flow reserve (CFR), increased microvascular resistance (IMR) or have evidence of microvascular spasms. Hence, invasive coronary function testing (CFT) is considered the reference standard for a definitive diagnosis of CMD. Patients with microvascular angina often have continuing episodes of chest pain leading to frequent first aid visits and hospital re-admissions with associated high health care costs. Moreover, CMD is associated with a worsened cardiovascular prognosis. Therefore, adequate treatment is paramount. However, current treatment options are based on a limited number of small studies, most of which were not placebo-controlled. Based on prior studies and our clinical experience we believe diltiazem, a calcium channel blocker (CCB) could improve coronary microvascular function in patients with CMD. Objective: Our primary objective is to assess the effect of diltiazem on coronary microvascular function as assessed by CFT in symptomatic patients with CMD. Our secondary objective is to assess the effect of diltiazem on the individual coronary function parameters. Study design: This is a clinical multi-center randomized with 1:1 ratio, double-blind, placebo-controlled study. Patients with chronic angina in the absence of obstructive CAD will be screened for study enrollment. Eligible patients will be asked for informed consent after which the screening visit will take place. Within 8 weeks after screening they will undergo CFT with the assessment of the coronary flow reserve (CFR), index of microcirculatory resistance (IMR) and coronary spasm. Intervention arm: if CFT shows either a CFR ≤ 2.0, an IMR ≥ 25 and/or coronary spasm, the patient will continue in the intervention arm of the trial and will be randomized to either diltiazem or placebo treatment for 6 weeks. After 6 weeks, a CFT will be repeated and the diltiazem/placebo treatment will be discontinued. Follow-up will be obtained after 6 weeks of treatment, and 1 year and 5 years after treatment discontinuation. Registration arm: If the CFT at baseline shows no signs of vascular dysfunction, patients will enter in the registration arm of the study. These patients will not receive any study medication. Follow-up will be obtained after 1 year and 5 years. Study population: Adult patients with chronic angina in the absence of obstructive CAD will be screened for participation. They will be recruited from the outpatient clinic of the cardiology department of the participating sites. Patients with contra-indications for coronary function testing (with the use of adenosine and acetylcholine) and/or diltiazem treatment (i.e. severe AV conduction delay, hypersensitivity, reduced left ventricular function) will not be eligible. Intervention: After establishing an abnormal coronary vascular function, 6 weeks treatment with either diltiazem 120-360 mg or placebo will be initiated in a double-blind fashion. Every two weeks dose titration will be performed if possible, under the guidance of patient tolerance (dizziness, leg oedema, etc.), blood pressure and heart rate. Main study parameters/endpoints: The proportion of patients having a successful treatment with diltiazem, defined as normalization of at least one abnormal parameter and none of the normal parameters becoming abnormal.. A normal IMR is specified as IMR < 25, a normal CFR being a CFR > 2 and a normal acetylcholine test is specified as one without ECG abnormalities and without signs of spasm at the same acetylcholine dose used at baseline. Main secondary endpoints will be the change in the individual coronary function parameters. Nature and extent of the burden and risks associated with participation, benefit and group relatedness: The extensive experience with diltiazem and the favourable safety profile in combination with the short duration of treatment make the treatment risk low for participants. Related to the study procedure several reports show that CFT is a safe procedure with serious complication rates (death, myocardial infaction, etc.) ranging from 0 to 0.7%. The first CFT is clinically indicated by the treating physician. The second CFT will bring additive risk to the participants in the intervention arm. However, we believe it is essential to investigate the effect of diltiazem on coronary function to justify its use in CMD patients.

In patients with chest pain and/or shortness of breath coronary artery disease (CAD) is suspected depending on the pattern of symptoms and the electrocardiogram (ECG). Coronary angiography is the method of choice to verify this suspicion. If the patient coronary arteries on coronary angiography are totally normal or unobstructed, one can only speculate if the patients' discomfort is from the heart or not. A possibility to get further information about the healthiness of the coronary arteries is the acetylcholine test (ACH-test). When injecting this natural, body produced-substance into the coronary arteries one can test if the vessels develop coronary spasm which can be the reason for the patient's symptoms. The investigators therefore use this test in this study to look for coronary spasm in patients with suspected CAD but normal/unobstructed coronary arteries. In case of a positive test, the patient profits from having found a cause for his/her symptoms making treatment with special tablets possible. Furthermore, the investigators want to analyze blood samples of every patient to look for signs of inflammation, vasoconstriction and genetic variants that seem to be linked with coronary spasms. On the basis of these results the ACH-test could probably be avoided in the future.

The goal of this registry is to collect data on patients referred for clinically indicated coronary vasomotor function test (CFT) and answer different questions on prevalence, safety and outcomes. The registry is observational. Patients receive yearly online questionnaires on their anginal complaints for 5 years after their CFT.

The goal of this prospective, multicenter registy is to describe the 'real-world' use of coronary function tests, which may consist of bolus thermodilution measurements of coronary microvascular function and/or invasive vasoreactivity tests with acetylcholine, in the current Belgian routine practice. The main questions it aims to answer are: how frequent are coronary function tests performed what is the indication for coronary function tests what is the frequency of coronary microvascular dysfunction what is the frequency of coronary artery vasospasm From each participant, data will be collected from their medical files concerning cardiovascular risk factors, relevant past medical history, non-invasive tests, procedural data, and follow-up data from routine in-patient visits. Their are no specific study visits. Optionally, patients will be asked to fill in questionnaires about anginal symptoms and quality of life.

The overall objective of this multi-center registry is to identify specific phenotypes of INOCA with both an anatomic evaluation (coronary angiography and intravascular imaging) and physiologic assessment with the Abbott Coroventis Coroflow Cardiovascular System, and to determine long-term outcomes.

AID-ANGIO is an observational, prospective, single arm, longitudinal study. Its objective is to investigate the diagnostic yield of the systematic use of a diagnostic strategy hierarchically addressing both obstructive and non-obstructive causes of myocardial ischaemia in an all-comers population of patients with chronic coronary syndromes (CCS) undergoing invasive coronary angiography (ICA). Angiographically severe-grade stenosis (≥70%) can be safely considered flow-limiting without further physiological assessment. Conversely, by means of a pressure guidewire, intermediate-grade stenosis would be evaluated with fractional flow reserve (FFR) and/or non-hyperaemic pressure ratios (NHPR) in order to determine if they are physiologically relevant. Those patients with non-obstructive CAD or normal epicardial coronary arteries would undergo functional coronary tests to investigate the presence of microcirculatory and vasomotor coronary disorders, which would account for non-obstructive causes of ischaemia. The main hypothesis of AID-ANGIO study states that, in patients with CCS referred to ICA, the application of a structured strategy -including ICA, physiological assessment of intermediate-grade stenosis and functional coronary tests- leads to a high diagnostic accuracy.

To compare clinical outcomes of myocardial infarction with non-obstructive coronary arteries (MINOCA) according to the coronary microvascular dysfunction (CMD), evaluated by optical coherence tomography (OCT), invasive and non-invasive coronary physiologic assessment.

The correlation between endothelial dysfunction and the risk of coronary heart disease is well known through previous studies. The degradation of the function of nitric oxide acting on the endothelium of blood vessels is mainly explained by reduction of synthesis, loss due to oxidative stress, and decreased sensitivity to vascular dilatation action. In particular, patients with high blood pressure have been known to have impaired vascular endothelial function through animal experiments and several clinical studies, mainly due to increased biomechanical friction in the blood vessels and decreased biological availability of nitric oxide, which in turn causes incongruity in the production of nitric monoxide and changes in normal vascular dilatation. There have also been reports recently that early diagnosis and treatment may improve endothelial dysfunction and prevent the progression of coronary artery disease. However, the reality is that the drugs available in vasospastic angina patients with endothelial dysfunction are very limited. Until recently, beta-blockers were reported to inhibit vascular dilatation of adrenaline stimuli, a drug corresponding to relative contraindications in vasospastic angina patients, with one study reporting that propranolol cannot, but rather exacerbates, vasospastic angina. However, a series of reports on the vascular dilatation of the recently developed third-generation beta-blockers have reinvented the role of beta-blockers in vasospastic angina, especially nebivolol (selective, continuous beta-blockers) is known to act on β-1 adrenaline receptor blockings and endothelium to create vascular dilatation, and also to stimulate β-3 adrenaline receptors to cause nitric oxide generation and antioxidant effects in the endothelium of blood vessels. Therefore, this clinical trial seeks to find whether nebivolol will inhibit vascular contraction in hypertensive patients and will work in angiospastic angina patients.

A randomized clinical trial comparing sequential nephron blockage (SNB) with dual blockade of the renin-angiotensin system (RAAS) plus bisoprolol (DBB) in the treatment of resistant arterial hypertension (RH) was designed to investigate the importance of the SNB and the contribution of its volume component versus DBB and the importance of the serum renin in maintaining BP levels. This randomized trial with two treatment arms could help tailor therapy by identifying a more effective choice to control hypertension whether by acting on the control of volume or sodium balance, or by acting on the effects of the RAAS on the kidney. Methods - Participants: 80 patients undergoing treatment for RH with losartan (100-200 mg), chlorthalidone (25 mg), and amlodipine (5 mg) will be randomly divided into two groups after applying inclusion and exclusion criteria. Group 1: Sequential nephron blockade (SNB Group) n = 40 Group 2: Dual blockade of the RAAS plus bisoprolol (DBB Group) n = 40 Intervention: SNB consists in a progressive increase in sodium depletion. After the administration of a thiazide diuretic (chlorthalidone) and aldosterone receptor blocker, low doses of furosemide are administered and subsequently amiloride is prescribed to enhance the natriuretic effect. The dual blockade of the RAAS plus bisoprolol is used to increase the effect of angiotensin receptor 1 blockers (ARBs). Therapy then requires sequentially adding an angiotensin converting enzyme (ACE) inhibitor to reduce the levels of angiotensin (Ang) II resulting from blockage of the Ang II receptor and then to administer a beta-blocker to decrease the elevated renin secretion due to both the ACE inhibitors and ARBs Objective: This study, which compares two antihypertensive treatment regimens in patients with RH, has the following objectives: to demonstrate the therapeutic efficacy of SNB against DBB in RH patients, and to assess the side effects and adherence to treatment over 20 weeks of treatment. Enrollment: The eligibility criteria will follow those shown in the flowchart for the diagnosis of RH of the First Brazilian Position on RH. Patients will be excluded if they have: chronic renal failure, atrial fibrillation/atrioventricular block, contraindication to the drugs that will be used, refusal or failure to follow the regimen and secondary hypertension. Follow-up: Patients will be analyzed in five visits at intervals of 28 days for 20 weeks