Intracoronary acetylcholine spasm testing: differences in epicardial coronary artery response between smooth and atherosclerotic coronary arteries

Background Coronary artery spasm is an established cause for angina pectoris. Epicardial coronary spasm may occur in patients with obstructed as well as unobstructed coronary arteries. Previous studies have suggested that epicardial plaque/atherosclerosis is a prerequisite for the development of epicardial spasm. The aim of the present study was to compare the results of intracoronary acetylcholine (ACh) testing in patients with signs and symptoms of myocardial ischemia with completely smooth versus atherosclerotic yet unobstructed epicardial arteries. Methods Between 2008 and 2016 a total number of 617 patients with signs and symptoms of myocardial ischemia yet unobstructed epicardial arteries (<50% epicardial stenosis) was included in the present study (mean age 61±11, 61% female). All patients underwent invasive diagnostic coronary angiography followed by intracoronary ACh testing according to a standardized protocol. The ACh-test was considered “positive” in the presence of (a) angina, ischemic ECG shifts during the test and ≥75% focal or diffuse coronary diameter reduction (“epicardial coronary artery spasm”) or (b) ischemic ST-shifts and angina in the absence of epicardial spasm (“microvascular spasm”). All angiograms were assessed regarding any visible epicardial plaque/atherosclerosis in a blinded fashion and patients were categorized into those with completely smooth versus those with atherosclerotic coronary arteries. The analysis included 179 patients (29%) with epicardial spasm and 172 patients with microvascular spasm (28%). The remaining 266 patients (43%) had an uneventful or an inconclusive ACh-test result. Results There were 389 patients (63%) with completely smooth epicardial arteries. The remaining 228 patients (37%) had non-obstructive epicardial plaques <50%. Patients with smooth arteries developed epicardial spasm in 24%, microvascular spasm in 32% and a negative/inconclusive test result in 44% of cases. Patients with atherosclerotic arteries developed epicardial spasm in 38%, microvascular spasm in 21% and an inconclusive/negative test result in 41% of cases. On univariate analysis the presence of epicardial atherosclerosis was associated with epicardial spasm (p=0.006) whereas this was not the case for microvascular spasm (p=0.094). Multivariate analysis revealed the presence of epicardial atherosclerosis (OR 1.921, CI 1.285–2.871, p=0.001) as well as female sex (OR 1.526, CI 1.024–2.274, p=0.038) as independent predictors for epicardial spasm. Conclusion In patients with signs and symptoms of myocardial ischemia yet unobstructed coronary arteries the presence of epicardial atherosclerosis is an independent predictor for the occurrence of epicardial spasm but not microvascular spasm on acetylcholine testing. Funding Acknowledgement Type of funding source: Foundation. Main funding source(s): Robert-Bosch-Stiftung, Berthold-Leibinger-Stiftung

ST-Segment Elevation Myocardial Infarction with Normal Coronary Arteries Angiography

: Myocardial infarction (MI) is the most frequent cause of ischemic heart death. MI is generally assumed to be due to arterial thrombosis superimposed on an atherosclerotic plaque in an epicardial coronary artery. Total occlusion of an epicardial coronary artery leads to ST elevation, while non-occlusive lesion leads to ST depression. We hereby have reported a case of ST-segment elevation myocardial infarction with normal coronary arteries angiography. A 35-year-old man presented with typical chest pain, nausea, vomiting and cold sweating. ECG obtained at admission and 30 minutes later revealed sinus tachycardia with ST-segment elevations (> 2 mm) in leads V2-V5. Cardiac biomarkers including creatine phosphokinase (CPK), creatine kinase muscle-brain (CK.MB) and troponin high sensitive were elevated. The standard treatment for MI including pain relief, aspirin, thrombolysis if indicated and beta blockade were begun for the patient. STEMI was confirmed and thus, angiography was performed. Coronary angiography revealed normal coronary arteries without any angiographic evidence of stenosis, coronary artery dissection, embolism, plaque rupture or vasospasm.

Recurrent asymptomatic Takotsubo syndrome after 20 years: are we looking at the tip of the iceberg only?

Takotsubo syndrome (TS) is an acute and reversible form of myocardial stunning preceded by emotional or physical stress, not explained by an obstruction of an epicardial coronary artery as in acute coronary syndrome. Over the last decades, TS is receiving growing attention, leading to an increase in awareness and diagnostic rate. Chest pain and dyspnea are the most common presenting symptoms; however, nonspecific presentations make the diagnosis challenging for clinicians. Here, we present the case of a 76-year-old female who experienced two completely asymptomatic episodes of TS 20 years apart.

Effects of Statin Treatment on Patients with Angina and Normal or Nearly Normal Angiograms

This article offers an updated and comprehensive overview of major findings on the effects of statin treatment in patients with chronic angina but without any epicardial coronary artery with obstructive lesion.

ESC Working Group on Coronary Pathophysiology and Microcirculation position paper on ‘coronary microvascular dysfunction in cardiovascular disease’

Although myocardial ischaemia usually manifests as a consequence of atherosclerosis-dependent obstructive epicardial coronary artery disease, a significant percentage of patients suffer ischaemic events in the absence of epicardial coronary artery obstruction. Experimental and clinical evidence highlight the abnormalities of the coronary microcirculation as a main cause of myocardial ischaemia in patients with ‘normal or near normal’ coronary arteries on angiography. Coronary microvascular disturbances have been associated with early stages of atherosclerosis even prior to any angiographic evidence of epicardial coronary stenosis, as well as to other cardiac pathologies such as myocardial hypertrophy and heart failure. The main objectives of the manuscript are (i) to provide updated evidence in our current understanding of the pathophysiological consequences of microvascular dysfunction in the heart; (ii) to report on the current knowledge on the relevance of cardiovascular risk factors and comorbid conditions for microcirculatory dysfunction; and (iii) to evidence the relevance of the clinical consequences of microvascular dysfunction. Highlighting the clinical importance of coronary microvascular dysfunction will open the field for research and the development of novel strategies for intervention will encourage early detection of subclinical disease and will help in the stratification of cardiovascular risk in agreement with the new concept of precision medicine.

P1436 Diagnostic yield and accuracy of CT coronary angiography compared to invasive coronary angiography: real world data from a district general hospital in the United Kingdom

Background Cost-effectiveness is imperative for a sustainable healthcare service. Non-invasive testing is used to risk stratify patients and reduce the need for invasive investigations in cardiology. The National Institute for Health and Care Excellence (NICE) Clinical Guideline for evaluation of chest pain was updated in 2016 when NICE recommended CT coronary angiography (CTCA) as the first-line investigation for patients with suspected stable coronary artery disease (CAD). Purpose To evaluate the accuracy of CTCA in real life daily practice in a district general hospital outside the strict environment of clinical trials. Methods A retrospective analysis of all CTCA studies carried out between June and December 2017 was performed. Graft studies were excluded. Potentially obstructive CAD on CTCA was defined as any luminal stenosis ≥50% of a major epicardial coronary artery. On invasive coronary angiography (ICA), clinically significant CAD was defined as a luminal stenosis of ≥50% in the left main stem or a stenosis of ≥70% of any other major epicardial coronary artery. Results Out of a total of 528 CTCA studies, 109 patients (mean age 64.2 ± 10.4; 67.9% male) showed potentially significant CAD in at least one major epicardial coronary artery. The median calcium score was 379.7 (IQR = 86-929). 61 (56%) patients had ICA, 20 (18.3%) patients had non-invasive functional coronary assessment (19 stress echocardiogram and 1 stress perfusion cardiac magnetic resonance) and 3 (2.8%) patients had both. The remaining patients were managed medically without further investigation. Correlation between potentially obstructive CAD on CTCA and clinically significant CAD on ICA showed a sensitivity of 95.8% (95% CI: 85.8%-99.5%), specificity of 68.0% (95% CI: 61.0%-74.5%), positive predictive value of 42.2% (95% CI: 37.1%-47.4%), negative predictive value of 98.5% (95% CI: 94.5%-99.6%) and overall accuracy of 73.5% (95% CI: 67.5%-78.9%). Among patients who had ICA, 21 patients (34.4%) required coronary revascularization (16 percutaneous coronary intervention and 5 coronary artery bypass grafting) and 40 (65.6%) patients were treated medically. Only 1 patient (4.3% of 23 patients) showed evidence of inducible ischemia on non-invasive functional testing. Conclusion CTCA in a real world practice has high sensitivity and high negative predictive value compared to the gold standard ICA. CTCA improved patient selection for ICA to those most likely to have significant CAD.