Left ventricular hypertrophy contributes to Myocardial Ischemia in Non-obstructive Coronary Artery Disease (the MicroCAD study)

Ingeborg Eskerud; Eva Gerdts; Terje H Larsen; Mai Tone Lønnebakken

doi:10.1016/j.ijcard.2019.03.059

Left ventricular hypertrophy contributes to Myocardial Ischemia in Non-obstructive Coronary Artery Disease (the MicroCAD study)

Int J Cardiol. 2019 Jul 1:286:1-6. doi: 10.1016/j.ijcard.2019.03.059. Epub 2019 Mar 28.

Authors

Ingeborg Eskerud¹, Eva Gerdts², Terje H Larsen³, Mai Tone Lønnebakken²

Affiliations

¹ Department of Clinical Science, University of Bergen, PO box 7804, N-5020 Bergen, Norway. Electronic address: ingeborg.eskerud@uib.no.
² Department of Clinical Science, University of Bergen, PO box 7804, N-5020 Bergen, Norway; Department of Heart Disease, Haukeland University Hospital, PO box 1400, N-5021 Bergen, Norway.
³ Department of Heart Disease, Haukeland University Hospital, PO box 1400, N-5021 Bergen, Norway; Department of Biomedicine, University of Bergen, PO box 7804, N-5020 Bergen, Norway.

PMID: 30952529
DOI: 10.1016/j.ijcard.2019.03.059

Abstract

Background: The underlying mechanisms causing myocardial ischemia in non-obstructive coronary artery disease (CAD) are still unclear. We explored whether left ventricular hypertrophy (LVH) was associated with myocardial ischemia in patients with stable angina and non-obstructive CAD.

Methods: 132 patients (mean age 63 ± 8 years, 56% women) with stable angina and non-obstructive CAD diagnosed as <50% stenosis by coronary computed tomography angiography (CCTA) underwent myocardial contrast stress echocardiography. Left ventricular (LV) hypertrophy (LVH) was identified by LV mass index >46.7 g/m^2.7 in women and >49.2 g/m^2.7 in men. Patients were grouped according to presence or absence of myocardial ischemia by myocardial contrast stress echocardiography. The number of LV segments with ischemia at peak stress was taken as a measure of the extent of myocardial ischemia.

Results: Myocardial ischemia was found in 52% of patients, with on average 5 ± 3 ischemic LV segments per patient. The group with myocardial ischemia had higher prevalence of LVH (23 vs. 10%, p = 0.035), while age, sex and prevalence of hypertension did not differ between groups (all p > 0.05). In multivariable regression analyses, LVH was associated with presence of myocardial ischemia (odds ratio 3.27, 95% confidence interval [1.11-9.60], p = 0.031), and larger extent of myocardial ischemia (β = 0.22, p = 0.012), independent of confounders including age, hypertension, obesity, hypercholesterolemia, calcium score and segment involvement score by CCTA.

Conclusions: LVH was independently associated with both presence and extent of myocardial ischemia in patients with stable angina and non-obstructive CAD by CCTA. These results suggest LVH as an independent contributor to myocardial ischemia in non-obstructive CAD.

Clinical trial registration number: ClinicalTrials.gov, identifier NCT018535271.

Keywords: Computed tomography coronary angiography; Hypertension; Left ventricular hypertrophy; Myocardial ischemia; Non-obstructive coronary artery disease.

MeSH terms

Computed Tomography Angiography
Coronary Angiography
Coronary Artery Disease / complications*
Coronary Artery Disease / diagnosis
Cross-Sectional Studies
Echocardiography, Stress
Female
Follow-Up Studies
Heart Ventricles / diagnostic imaging*
Heart Ventricles / physiopathology
Humans
Hypertrophy, Left Ventricular / complications*
Hypertrophy, Left Ventricular / diagnosis
Hypertrophy, Left Ventricular / physiopathology
Incidence
Male
Middle Aged
Myocardial Ischemia / diagnosis
Myocardial Ischemia / epidemiology
Myocardial Ischemia / etiology*
Norway / epidemiology
Retrospective Studies
Ventricular Function, Left / physiology*