Spontaneous multi-focal coronary artery spasm: a case report

Intracoronary injection of nitroglycerine can prevent unnecessary percutaneous coronary intervention

Background

Despite the recommendation of the current guidelines, intracoronary administration of nitroglycerine during coronary angiography is often neglected. We investigated the effect of intra-coronary nitroglycerin on the relief of coronary artery stenosis in the candidates for percutaneous coronary intervention (PCI).

Methods

We included patients with angina pectoris or myocardial infarction who were candidates for PCI. In the coronary angiography, the culprit vessel involved was evaluated, and bolus nitroglycerin at a dose of 25–200 mcg was injected into the affected coronary artery. A significant change in the percentage of coronary artery stenosis was considered a positive response, and these patients were then compared with patients who did not have a substantial change in the percentage of stenosis at the same time. Univariate analysis and then multivariate logistic regression analysis was performed to determine the predictors of response to intracoronary nitroglycerin.

Results

Among 360 patients, 27 (7.5%) responded to nitroglycerine, and 333 (92.5%) were non-responsive. The mean age of patients was 60.2 ± 11.6 years, ranging from 23 to 93 years, and 265 (73.6%) were men. The study groups were not significantly different in the baseline demographic characteristics. The presence of multivessel disease (Odds ratio (OR) = 16.26, 95% confidence interval (CI):2.07–127.6; P = 0.008) and stenosis in the left circumflex artery (OR = 3.62, 95% CI: 1.03–12.70; P = 0.044) were the independent predictors for nonresponse to nitroglycerine, leading to PCI.

Conclusion

In some cases, especially those without multivessel diseases, intracoronary nitroglycerine administration can efficiently relieve coronary stenosis and prevent unnecessary PCI.

Coincidence between spontaneous and inducible coronary spasm: acetylcholine test is clinically valued for diagnosing coronary spasm

There is no report regarding the correlation between spontaneous documented coronary spasm and acetylcholine (ACh)-inducible spasm. We retrospectively analyzed the coincidence between angiographical spontaneous coronary spasm and ACh-inducible spasm in the same patients. We recruited 28 patients with 30 angiographical spontaneous coronary spasm in 6009 patients with diagnostic and follow-up coronary arteriography from Jan 1991 and Mar 2019 in the cardiac catheterization laboratory. We could perform intracoronary ACh testing in 19 patients with 20 vessels. ACh was injected in incremental dose of 20/50/100 μg into the left coronary artery and 20/50/80 μg into the right coronary artery. Positive spasm was defined as > 90% stenosis and ischemic ECG changes. Angiographical documented spontaneous coronary spasm was observed in 0.47% (28/6009) of patients with diagnostic and follow-up coronary angiography. Intracoronary administration of ACh reproduced 15 spontaneous coronary spasm and no provoked spasm was observed in the remaining 5 vessels due to the administration of nitroglycerine or under medications. Spasm-provoked sites by ACh tests and ACh-inducible spasm configurations were almost similar to spontaneous spasm. Coincidence of provoked spasm site (93.3% vs. 6.7%, p < 0.001) and spasm configuration (93.3% vs. 6.7%, p < 0.001) was markedly higher than discordance. Intracoronary ACh testing can reproduce spontaneous coronary artery spasm in 75% of vessels with almost similar sites and same morphological characteristics irrespective of the administration of nitroglycerine or vasodilators. ACh test is a reliable method to document coronary artery spasm in the clinic.

Bioaccumulation of ytterbium oxide nanoparticles insinuate oxidative stress, inflammatory, and pathological lesions in ICR mice

With the rapid development in nanoscience and nanotechnology, rare earth oxide nanomaterials (REO-NMs) have been increasingly used due to their unique physical and chemical characteristics. Despite the increasing applications of REO NPs, scarce information is available on their detrimental effects. In the current study, we investigate the toxic effect of ytterbium oxide nanoparticles (Yb₂O₃ NPs) in mouse model by using various techniques including inductively coupled plasma mass spectrometry (ICP-MS) analysis over 30 days of exposure. Furthermore, we elucidated lung lavage fluid of mice for biochemical and cytological analysis, and lung tissues for histopathology to interpret the NP side effects. We observed a significant concentration of Yb₂O₃ NPs accumulated in the lung, liver, kidney, and heart tissues. Similarly, increased bioaccumulation of Yb content was found in the olfactory bulb compared to other reigns of brain. The cytological analysis of bronchoalveolar lavage fluid (BALF) revealed a significant elevation in the percentage of neutrophils and lymphocytes. Biochemical analysis showed an instilled Yb₂O₃ NPs, showing signs of oxidative damage through up-regulation of 60-87% of MDA while down-regulation of 20-40% of GSH-PX and GSH content. The toxicity pattern was more evident from histopathological observations. These interpretations provide enough evidence of bioaccumulation of Yb₂O₃ NPs in mice tissues. Overall, our findings reveal that acute exposure of Yb₂O₃ NPs through intranasal inhalation may cause toxicity via oxidative stress, which leads to a chronic inflammatory response. Graphical abstract Graphical illustrations of experimental findings.