Coronary Slow-Flow Phenomenon as an Underrecognized and Treatable Source of Chest Pain: Case Series and Literature Review

Abstract

Background. Coronary slow-flow phenomenon (CSFP) is characterized by delayed distal vessel opacification of contrast, in the absence of significant epicardial coronary stenosis. CSFP has been reported as a cause of chest pain and abnormal noninvasive ischemic tests and is often underrecognized. Material and Methods. Charts and angiographic records from our institution were reviewed to identify 15 consecutive patients who were diagnosed with CSFP from January 2016 to January 2017. Results. Of the 15 patients (4 females and 11 males) studied, the mean age was 59.1 years (range = 45-86 years); all had left ventricular ejection fraction >45% and without significant valvular stenosis/regurgitation. The indication for coronary angiography for all 15 patients was chest pain with abnormal noninvasive tests. Of the 11 patients who underwent previous coronary angiograms, all revealed prior evidence of CSFP. None of these patients were on calcium channel blockers (CCBs) or long-acting nitroglycerin agents before angiography. Intracoronary CCBs were effectively utilized to alleviate the angiographic finding (improvement in Thrombolysis in Myocardial Infarction frame count) in all 15 patients. Oral CCBs were started with subsequent improvement in all 15 patients (mean follow-up time = 13.6 months). Conclusion. Coronary slow-flow should be a diagnostic consideration in patients presenting with chest pain and abnormal noninvasive ischemic testing with nonobstructive epicardial vessels. CSFP remains underrecognized, and the specific standard of care for treatment has not been established. In each of the 15 cases, intracoronary nifedipine resolved the angiographic manifestation of coronary slow-flow. Furthermore, in follow-up, all patients improved symptomatically from their chest pain after oral CCBs were initiated.

Myocardial Infarction Secondary to Marijuana-Induced Coronary Vasospasm

“…It is likely based on these findings that CSFP is multifactorial, altering the endothelium on a biochemistry level. Coronary angiograms in these patients with CSFP are classically referred to as "negative and normal," or to have "minimal non-obstructive disease," which leads to patients being referred to as negative cardiac catheterization myocardial infarctions [19,20]. These findings correlate with what was seen objectively within our case report.…”

The Effect of Angiotensin-Converting Enzyme Gene Polymorphisms in the Coronary Slow Flow Phenomenon at South Sumatra, Indonesia Population

“…Aldosterone is one of the other proteins that regulate the rigidity of vascular tone by increasing accumulation of fibrotic tissue and is responsible in endothelial dysfunction. The result of this study was different with the previous studies [1], [13], [14]. The study showed II genotype was the risk factor in CSFP patients.…”

An investigation of the relationship between arterial aortic stiffness and coronary slow flow that was detected during coronary angiography

“…TIMI frame counts were evaluated in 15 frames per second, which was multiplied by two times for 30 frame equivalence 22 . The corrected TIMI frame count for LAD was calculated by dividing the corrected TIMI frame count of a left descending artery by 1.7.…”