Clinical Characteristics and Prognosis of Patients with Vasospastic Angina Subjected to the Spasm Provocation Test and the Unavoidable Use of Nitroglycerin

Abstract

Background: Multi-vessel spasm (MVS) has a prognostic impact in patients with vasospastic angina (VSA). Thus, the presence of coronary spasm in both the left coronary artery (LCA) and right coronary artery (RCA) should be assessed through the spasm provocation test (SPT). Nitroglycerin (NTG) is used to avoid SPT-related complications; however, this unavoidable use of NTG may decrease the detection of MVS. Therefore, we investigated the frequency of the unavoidable use of NTG during SPT and clarified the clinical characteristics in patients with VSA who underwent the unavoidable use of NTG during STP. Methods: A total of 141 patients with positive SPT were evaluated. A positive SPT was defined as > 90% constriction in epicardial coronary arteries in response to acetylcholine, accompanied by the usual chest symptoms and/or ischaemic ST-T changes on electrocardiography. When a coronary spasm occurred, we usually wait for the spontaneous relief of the coronary spasm. However, if a prolonged coronary spasm or unstable haemodynamics occurred, 0.3 mg NTG was administered intracoronarily to promptly relieve the coronary spasm and this was defined as the unavoidable use of NTG. Even when the unavoidable use of NTG was administered in one coronary artery, an additional SPT was performed on another coronary artery. If a coronary spasm occurred in another coronary artery, a positive SPT was diagnosed. In contrast, if a coronary spasm was not induced after the unavoidable use of NTG, the judgement was classified as undiagnosed. The patients were divided into two groups according to the unavoidable use of NTG: U-NTG (n = 42) and the final use of NTG: F-NTG (n = 99). The clinical characteristics and frequencies of MVS (≥2 major coronary arteries in which a coronary spasm was provoked) and complications (malignant arrhythmia and unstable haemodynamics requiring catecholamines) during the SPT were compared between the groups. Results: Except for smoking status, all other clinical characteristics did not differ significantly between the groups. More current smokers were observed in the U-NTG group (29%) than in the F-NTG group (12%, p = 0.02). The frequency of MVS did not vary significantly between the groups (p = 0.28), with 64% for U-NTG and 55% for F-NTG. No significant difference was found between the groups in the frequency of severe complications during SPT (p = 0.83), with 2% for U-NTG and 3% for F-NTG. In the U-NTG group, the positive induction rate of coronary spasm in another coronary artery was 40% (17/42). Conclusions: The unavoidable use of NTG occurred in ~30% of patients with VSA, most of whom were current smokers. It did not decrease the detection of MVS and potentially prevented severe complications during SPT. Therefore, the unavoidable use of NTG is acceptable during SPT. However, an additional test may need to be performed to assess the presence of MVS.

Vasospastic angina in women: Clinical backgrounds and prognoses of patients younger than and older than 60 years

“…In any case, the fact that coronary spasms in the LCX were more frequent in women aged < 60 years suggests that muscarinic receptor distribution may change with age in women with VSA. The unavoidable use of NTG was reported to be associated with more active coronary spasms[ 13 ], which may suggest that women aged < 60 years with VSA have more active coronary spasms.…”

“…In such circumstances, NTG injection into the RCA was performed after performing the SPT for the LCA. An intracoronary injection of 0.3 mg NTG was administered to ease spasms if the Ach-induced coronary spasms were severe enough to cause hemodynamic instability; this was referred to as the unavoidable use of NTG[ 13 ]. SPT of the LCA was then carried out using 50 and 100 mg of ACh.…”

Frequency and Clinical Impact of Family History of Coronary Artery Disease in Patients with Vasospastic Angina

“…In order to calculate the left ventricular ejection fraction (LVEF), cardiac ultrasonography was used. As previously mentioned [ 33 , 34 ], the functions of endothelium-dependent flow-mediated dilatation (FMD) and endothelium-independent NTG-induced dilation (NID) were evaluated.…”

“…The number of coronary vasodilators was assessed at the last follow-up. Cardiac events were tracked, including readmission for angina or other cardiovascular problems, and major adverse cardiovascular events (MACEs) were defined as death from cardiac causes or readmission for cardiovascular reasons [ 24 , 33 , 34 ].…”