Myocardial perfusion by CMR coronary sinus flow shows sex differences and lowered perfusion at stress in patients with suspected microvascular angina

Abstract

Background Patients with chest pain may have normal coronary arteries and suffer from microvascular angina (MVA). The aim of this study was to determine if patients with suspected MVA have lower global myocardial perfusion (global MP) during adenosine stress compared with healthy controls and coronary artery disease (CAD) patients and to determine if there are sex differences in global MP. Methods Twenty‐three patients with suspected MVA (66 ± 11 years), 19 CAD patients (69 ± 5 years) with stress‐induced ischaemia and 24 healthy controls (61 ± 10 years) underwent cardiac magnetic resonance (CMR) including coronary sinus flow measurements and first‐pass perfusion at rest and during adenosine stress. Global MP was quantified as coronary sinus flow normalized to left ventricular mass. Results Global perfusion was lower during stress in patients with suspected MVA (2.9 ± 1.0 ml/min/g) compared with healthy volunteers (3.7 ± 1.1 ml/min/g, p = 0.018), but higher compared with CAD patients (2.0 ± 0.9 ml/min/g, p = 0.019). Female controls had higher global MP than male controls both at rest (1.0 ± 0.3 vs. 0.7 ± 0.2 ml/min/g, p = 0.003) and during stress (4.4 ± 1.0 vs. 3.1 ± 0.6 ml/min/g, p = 0.001). Furthermore, females with suspected MVA showed higher global MP than males with suspected MVA (3.3 ± 1.0 vs. 2.4 ± 0.7, p = 0.04). Conclusions Patients with suspected MVA have lower global MP at stress than healthy volunteers but higher than patients with CAD. Furthermore, there seems to be a sex difference in global MP at stress both in healthy volunteers and in patients with suspected MVA, with higher global MP in females, which implies a need for sex‐specific normal limits when assessing quantitative MP.

Quantitative myocardial perfusion should be interpreted in the light of sex and comorbidities in patients with suspected chronic coronary syndrome: A cardiac positron emission tomography study

“…The sex differences in myocardial perfusion min at stress shown in the current study support findings in previous studies using PET (Danad et al, 2014) and CMR (Gyllenhammar et al, 2022;Nickander et al, 2020) in both healthy subjects and patients. It has been shown…”

“…In the current study, it was shown that females referred for coronary angiography due to angina have a significantly higher myocardial perfusion at stress compared to males in myocardium supplied with coronary arteries with <50% stenosis, which might be explained by differences in the presence of microvascular disease or diffuse coronary atherosclerosis. This difference has previously also been shown in healthy volunteers (Gyllenhammar et al, 2022; Nickander et al, 2020). Furthermore, females often present with nonsignificant coronary artery stenosis on coronary angiographies, more so than males (Shaw, Berman, et al, 2008).…”

Coronary flow reserve evaluated by phase-contrast cine cardiovascular magnetic resonance imaging of coronary sinus: a meta-analysis

“…Therefore, a total of 67 independent populations were included. Among the 47 studies, 22 were from Japan [ 19 – 21 , 23 – 37 , 42 , 44 , 45 , 47 ], eight from the United States [ 7 , 14 , 22 , 40 , 41 , 48 , 51 , 55 ], five from Sweden [ 12 , 16 , 17 , 53 , 54 ], three from Germany and Sweden [ 11 , 15 , 46 ], two from Finland [ 38 , 39 ], and one each from Australia [ 18 ], France [ 43 ], Italy [ 9 ], Norway [ 13 ], Turkey [ 10 ], the United Kingdom [ 49 ], Switzerland [ 7 ], and the Netherlands [ 50 ]. Year of publication ranged from 1992 to 2022.…”

“…In four studies [ 10 , 12 , 40 , 48 ], the VENC during stress was 200 cm/s. In the study by Gyllenhammar et al [ 16 ], the VENC was 120 cm/s. According to Moro et al [ 43 ], the VENC was 150 cm/s.…”