The microvascular effects of insulin resistance and diabetes on cardiac structure, function, and perfusion: a cardiovascular magnetic resonance study.

Aims: Type 2 diabetes mellitus is an independent risk factor for the development of heart failure. To better understand the mechanism by which this occurs, we investigated cardiac structure, function, and perfusion in patients with and without diabetes.

Methods And Results: Sixty-five patients with no stenosis >30% on invasive coronary angiography were categorized into diabetes (19) and non-diabetes (46) which was further categorized into prediabetes (30) and controls (16) according to the American Diabetes Association guidelines.

Cardiac MR imaging to measure myocardial blood flow response to the cold pressor test in healthy smokers and nonsmokers.

Purpose: To determine if myocardial perfusion cardiac magnetic resonance (MR) imaging can show changes in myocardial blood flow (MBF) during the cold pressor test (CPT) and can allow identification of the differing endothelial function of smokers and nonsmokers when compared during adenosine stress.

Materials And Methods: The study was approved by the institutional ethics review board and all participants gave informed written consent. Twenty-nine healthy volunteers (19 nonsmokers, 10 smokers; mean age ± standard deviation, 22 years ± 4) underwent 1.

Reproducibility of myocardial strain and left ventricular twist measured using complementary spatial modulation of magnetization.

Purpose: To establish the reproducibility of complementary spatial modulation of magnetization (CSPAMM) tagged cardiovascular MR (CMR) data in normal volunteers.

Materials And Methods: Twelve healthy volunteers underwent CMR studies on two separate occasions using an identical CSPAMM pulse sequence with images acquired in three short axis slices. Data were analyzed by two independent observers using harmonic phase analysis (HARP).

Myocardial blood flow at rest and stress measured with dynamic contrast-enhanced MRI: comparison of a distributed parameter model with a Fermi function model.

Purpose: To assess the feasibility of simultaneously measuring blood flow (Fb ), Gd-DTPA extraction fraction (E), and distribution volume (vd ) in healthy myocardium at rest and under adenosine stress using dynamic contrast-enhanced MRI.

Methods: Sixteen volunteers were examined at 1.5 T and 11 returned for a repeat study.

Reproducibility of first-pass cardiovascular magnetic resonance myocardial perfusion.

Purpose: To assess the reproducibility of semiquantitative and quantitative analysis of first-pass myocardial perfusion cardiovascular magnetic resonance (CMR) in healthy volunteers.

Materials And Methods: Eleven volunteers underwent myocardial perfusion CMR during adenosine stress and rest on 2 separate days. Perfusion data were acquired in a single mid-ventricular section in two cardiac phases to permit cardiac phase reproducibility comparisons.

Systolic versus diastolic acquisition in myocardial perfusion MR imaging.

Purpose: To compare myocardial blood flow (MBF) at systole and diastole and determine the diagnostic accuracy of both phases in patients suspected of having coronary artery disease (CAD).

Materials And Methods: The study was approved by the regional ethics committee, and all patients gave written informed consent. After coronary angiography, 40 patients (27 men; mean age, 64 years ± 8) underwent stress-rest perfusion magnetic resonance (MR) imaging at 1.

Endocardial and epicardial myocardial perfusion determined by semi-quantitative and quantitative myocardial perfusion magnetic resonance.

This study aims to quantify subendocardial and subepicardial myocardial blood flow (MBF) from dynamic contrast-enhanced MRI and to compare semi-quantitative and quantitative analysis methods. 17 healthy volunteers (9 males, mean age 34 ± 8) were scanned during adenosine stress and at rest. A "semi-quantitative" myocardial perfusion index (MPI) was calculated based on maximal upslopes of signal intensity-time profiles for a mid-ventricular myocardial slice.

Estimates of systolic and diastolic myocardial blood flow by dynamic contrast-enhanced MRI.

Myocardial blood flow varies during the cardiac cycle in response to pulsatile changes in epicardial circulation and cyclical variation in myocardial tension. First-pass assessment of myocardial perfusion by dynamic contrast-enhanced MRI is one of the most challenging applications of MRI because of the spatial and temporal constraints imposed by the cardiac physiology and the nature of dynamic contrast-enhanced MRI signal collection. Here, we describe a dynamic contrast-enhanced MRI method for simultaneous assessment of systolic and diastolic myocardial blood flow.

Effect of improving spatial or temporal resolution on image quality and quantitative perfusion assessment with k-t SENSE acceleration in first-pass CMR myocardial perfusion imaging.

k-t Sensitivity-encoded (k-t SENSE) acceleration has been used to improve spatial resolution, temporal resolution, and slice coverage in first-pass cardiac magnetic resonance myocardial perfusion imaging. This study compares the effect of investing the speed-up afforded by k-t SENSE acceleration in spatial or temporal resolution. Ten healthy volunteers underwent adenosine stress myocardial perfusion imaging using four saturation-recovery gradient echo perfusion sequences: a reference sequence accelerated by sensitivity encoding (SENSE), and three k-t SENSE-accelerated sequences with higher spatial resolution ("k-t High"), shorter acquisition window ("k-t Fast"), or a shared increase in both parameters ("k-t Hybrid") relative to the reference.