Markl, Michael

BACKGROUND: Although chronic obstructive pulmonary disease (COPD) and heart failure with preserved ejection fraction often coexist with overlapping clinical features, they are usually studied separately. The SPIROMICS HF (Subpopulations and Intermediate Outcome Measures in COPD and Heart Failure Study) is testing hypotheses that new computed tomography emphysema subtypes are associated with specific cardiovascular phenotypes (eg, cor pulmonale , cor pulmonale parvus ), common airway branch variants are associated with right heart dysfunction, and symptomatic tobacco-exposed persons with preserved spirometry have signs of increased left ventricular afterload. METHODS: SPIROMICS is a multicenter observational study of COPD with extensive pulmonary phenotyping of participants with ≥20 pack-years smoking and nonsmoking controls. COPD and COPD severity were defined by standard spirometric criteria and symptomatic tobacco-exposed persons with preserved spirometry by ≥20 pack-years, normal spirometry, and COPD Assessment Test score >10. SPIROMICS HF selected all participants in SPIROMICS visit 5 at major sites. Its comprehensive speckle-tracking echocardiography, which included physiological perturbations of leg raise and low-intensity exercise, was harmonized prospectively with the Multi-Ethnic Study of Atherosclerosis Early Heart Failure and HeartSHARE (Combining Omics, Deep Phenotyping, and Electronic Health Records for Heart Failure Subtypes and Treatment Targets) studies. The cardiopulmonary magnetic resonance imaging protocol with gadolinium administration included myocardial fibrosis sequences, pulmonary angiography, time-resolved 3-dimensional cine magnetic resonance imaging (4-dimensional flow) of venous return, and metronome-paced tachypnea to induce dynamic hyperinflation. Coronary artery calcium was assessed on computed tomography scans. The Kansas City Cardiomyopathy Questionnaire was administered. RESULTS: Of the final sample of 753 participants, 57% had COPD (15% mild, 27% moderate, and 15% severe), 18% had symptomatic tobacco-exposed persons with preserved spirometry, 16% were smoking controls, and 8% were nonsmoking controls. Reproducibility of the main measures from speckle-tracking echocardiography (intraclass correlation coefficient, 0.83–0.99), exercise echocardiography (intraclass correlation coefficient, 0.71–0.99) and magnetic resonance imaging (intraclass correlation coefficient, 0.57–0.99) were good-to-excellent, including in severe COPD. CONCLUSIONS: SPIROMICS HF aims to characterize and understand cardiopulmonary interactions in COPD and COPD-related phenotypes to inform targeted treatments for combined cardiopulmonary failure.

AbstractPurposeOverall there is a lack of evidence on the accuracy and precision of phase‐contrast (PC) MRI in patients with cardiac implantable electronic devices (CIEDs). The purpose of this study is to determine whether aortic velocity measurements are influenced by a CIED.MethodsWe scanned 21 adult patients and 8 pediatric volunteers using clinical standard PC and real‐time PC (rt‐PC) sequences with and without a CIED generator taped on human subjects (below the left clavicle for adults and children; also on the abdomen for children) to mimic image artifacts. Peak and mean velocities above the aortic valve were calculated.ResultsThe Bland–Altman analyses on peak velocity measurements in pediatric subjects showed that both the accuracy and precision worsen as the distance between the CIED and aortic valve decreases (i.e., from abdomen to below the left clavicle). Specifically, both the bias and the coefficient of variation (CV) for both clinical PC and rt‐PC increased from the abdominal position (clinical: bias = −1.1%, CV = 4.3%; rt‐PC: bias = −0.3%, CV = 3.4%) to the clavicle position (clinical: bias = −4.0%, CV = 8.1%; rt‐PC: bias = 8.2%, CV = 7.3%). A similar trend was observed for mean velocity. The mean difference in peak and mean velocity measurements between rt‐PC with CIED (either position) and clinical standard PC with no CIED was within 7.5%. In adult patients, the mean difference between rt‐PC with CIED and clinical standard PC with CIED in peak velocity was 6.9%, and the CV was 7.9%.ConclusionThis study demonstrates that aortic velocity measurements are influenced by CIED in both adult and pediatric subjects.

Abstract This International Consensus Classification and Nomenclature for the congenital bicuspid aortic valve condition recognizes 3 types of bicuspid valves: 1. The fused type (right-left cusp fusion, right-non-coronary cusp fusion and left-non-coronary cusp fusion phenotypes); 2. The 2-sinus type (latero-lateral and antero-posterior phenotypes); and 3. The partial-fusion (forme fruste) type. The presence of raphe and the symmetry of the fused type phenotypes are critical aspects to describe. The International Consensus also recognizes 3 types of bicuspid valve-associated aortopathy: 1. The ascending phenotype; 2. The root phenotype; and 3. Extended phenotypes.

Abstract This International evidence-based nomenclature and classification consensus on the congenital bicuspid aortic valve and its aortopathy recognizes 3 types of bicuspid aortic valve: 1. Fused type, with 3 phenotypes: right-left cusp fusion, right-non cusp fusion and left-non cusp fusion; 2. 2-sinus type with 2 phenotypes: Latero-lateral and antero-posterior; and 3. Partial-fusion or forme fruste. This consensus recognizes 3 bicuspid-aortopathy types: 1. Ascending phenotype; root phenotype; and 3. extended phenotypes.

BackgroundStroke etiology is undetermined in approximately one‐sixth to one‐third of patients. The presence of aortic flow reversal and plaques in the descending aorta (DAo) has been identified as a potential retrograde embolic mechanism.PurposeTo assess the relationships between aortic stiffness, wall thickness, and flow reversal in patients with cryptogenic stroke and healthy controls.Study TypeProspective.PopulationTwenty one patients with cryptogenic stroke and proven DAo plaques (69 ± 9 years, 43% female), 18 age‐matched controls (age: 65 ± 8 years, 61% female), and 14 younger controls (36 ± 9 years, 57% female).Field Strength/Sequence1.5T; 4D flow MRI and 3D dark blood T1‐weighted turbo spin echo MRI of the aorta.AssessmentNoncontrast aortic 4D flow MRI to measure 3D flow dynamics and 3D dark blood aortic wall MRI to assess wall thickness. 4D flow MRI analysis included automated quantification of aortic stiffness by pulse wave velocity (PWV) and voxelwise mapping of the flow reversal fraction (FRF).Statistical TestsAnalysis of variance (ANOVA) or Kruskal–Wallis tests, Student's unpaired t‐tests or Wilcoxon rank‐sum tests, regression analysis.ResultsAortic PWV and FRF were statistically higher in patients (8.9 ± 1.7 m/s, 18.4 ± 7.7%) than younger controls (5.3 ± 0.8 m/s, P < 0.0167; 8.5 ± 2.9%, P < 0.0167), but not age‐matched controls (8.2 ± 1.6 m/s, P = 0.22; 15.6 ± 5.8%, P = 0.22). Maximum aortic wall thickness was higher in patients (3.1 ± 0.7 mm) than younger controls (2.2 ± 0.2 mm, P < 0.0167) and age‐matched controls (2.7 ± 0.5 mm) (P < 0.0167). For all subjects, positive relationships were found between PWV and age (R2 = 0.71, P < 0.05), aortic wall thickness (R2 = 0.20, P < 0.05), and FRF (R2 = 0.47, P < 0.05). Patients demonstrated relationships between PWV and FRF in the ascending aorta (R2 = 0.32, P < 0.05) and arch (R2 = 0.24, P < 0.05).Data ConclusionThis study showed the utility of 4D flow MRI for evaluating aortic PWV and voxelwise flow reversal. Positive relationships between aortic PWV, wall thickness, and flow reversal support the hypothesis that aortic stiffness is involved in this retrograde embolic mechanism.Level of Evidence2Technical Efficacy Stage1

Background Blood flow reversal is a possible mechanism for retrograde embolism in the setting of high‐risk atherosclerotic plaques in the descending aorta (DAo). Evidence suggests that pulse wave velocity (PWV) is a determinant of blood flow reversal and can be reduced by the destiffening effect of renin‐angiotensin system inhibitors (RASI). Purpose To evaluate the impact of antihypertensive therapy on in vivo changes in PWV and flow reversal in patients with cryptogenic stroke. Study Type Prospective. Population Sixteen patients (69 ± 9 years; 10 males) included after cryptogenic stroke. Field Strength/Sequence 3T. 4D flow sequence (temporal resolution = 19.6 msec) Assessment Patients underwent aortic MRI at baseline and at 6‐month follow‐up. Patients received standard‐of‐care antihypertensive therapy that were classified as RASI vs. non‐RASI medications (ie, destiffening vs. nondestiffening).We compared aortic PWV, flow reversal fraction (FRF), aortic measurements, cardiac function, and other aortic and cardiac measurements in the antihypertensive therapy groups. Statistical Tests Two‐tailed paired or unpaired Student's t ‐tests (normal distributions) or Wilcoxon tests (nonnormal distribution). Univariate correlations using Pearson correlation coefficients. Results There was a significant decrease in PWV in the RASI ( n = 10) group (9.4 ± 1.6 m/s vs. 8.3 ± 1.9 m/s; P < 0.05), as well as FRF (18.6% ± 4.1% vs. 16.3% ± 4.0%; P < 0.05) between baseline and the 6‐month MRI studies. There were no changes in PWV or FRF in the non‐RASI ( n = 6) group ( P = 0.146 and P = 0.32). A decrease in FRF was significantly correlated with a decrease in PWV ( r = 0.53; P < 0.05). Data Conclusion The findings of our study suggest that RASI therapy after cryptogenic stroke resulted in a decrease of blood flow reversal and aortic stiffness. Evidence Level 1 Technical Efficacy Stage 4

BackgroundDoxorubicin and doxorubicin‐trastuzumab combination chemotherapy have been associated with cardiotoxicity that eventually leads to heart failure and may limit dose‐effective cancer treatment. Current diagnostic strategies rely on decreased ejection fraction (EF) to diagnose cardiotoxicity.PurposeThe aim of this study is to explore the potential of cardiac MR (CMR) imaging to identify imaging biomarkers in a mouse model of chemotherapy‐induced cardiotoxicity.MethodsA cumulative dose of 25 mg/kg doxorubicin was administered over three weeks using subcutaneous pellets (n = 9, Dox). Another group (n = 9) received same dose of Dox and a total of 10 mg/kg trastuzumab (DT). Mice were imaged at baseline, 5/6 weeks and 10 weeks post‐treatment on a 7T MRI system. The protocol included short‐axis cine MRI covering the left ventricle (LV) and mid‐ventricular short‐axis tissue phase mapping (TPM), pre‐ and post‐contrast T1 mapping, T2 mapping and Displacement Encoding with Stimulated Echoes (DENSE) strain encoded MRI. EF, peak myocardial velocities, native T1, T2, extracellular volume (ECV), and myocardial strain were quantified. N = 7 mice were sacrificed for histopathologic assessment of apoptosis at 5/6 weeks.ResultsGlobal peak systolic longitudinal velocity was reduced at 5/6 weeks in Dox (0.6 ± 0.3 vs 0.9 ± 0.3, p = 0.02). In the Dox group, native T1 was reduced at 5/6 weeks (1.3 ± 0.2 ms vs 1.6 ± 0.2 ms, p = 0.02), and relatively normalized at week 10 (1.4 ± 0.1 ms vs 1.6 ± 0.2 ms, p > 0.99). There was no change in EF and other MRI parameters and histopathologic results demonstrated minimal apoptosis in all mice (~1–2 apoptotic cell/high power field), suggesting early‐stage cardiotoxicity.ConclusionsIn a mouse model of chemotherapy‐induced cardiotoxicity using doxorubicin and trastuzumab, advanced CMR shows promise in identifying treatment‐related decrease in myocardial velocity and native T1 prior to the onset of cardiomyocyte apoptosis and reduction of EF.

Background: Four-dimensional (D) flow magnetic resonance imaging (MRI) is limited by time-consuming and nonstandardized data analysis. We aimed to test the efficiency and interobserver reproducibility of a dedicated 4D flow MRI analysis workflow. Materials and Methods: Thirty retrospectively identified patients with bicuspid aortic valve (BAV, age=47.8±11.8 y, 9 male) and 30 healthy controls (age=48.8±12.5 y, 21 male) underwent Aortic 4D flow MRI using 1.5 and 3 T MRI systems. Two independent readers performed 4D flow analysis on a dedicated workstation including preprocessing, aorta segmentation, and placement of four 2D planes throughout the aorta for quantification of net flow, peak velocity, and regurgitant fraction. 3D flow visualization using streamlines was used to grade aortic valve outflow jets and extent of helical flow. Results: 4D flow analysis workflow time for both observers: 5.0±1.4 minutes per case (range=3 to 10 min). Valve outflow jets and flow derangement was visible in all 30 BAV patients (both observers). Net flow, peak velocity, and regurgitant fraction was significantly elevated in BAV patients compared with controls except for regurgitant fraction in plane 4 (91.1±29.7 vs. 62.6±19.6 mL/s, 37.1% difference; 121.7±49.7 vs. 90.9±26.4 cm/s, 28.9% difference; 9.3±10.1% vs. 2.0±3.4%, 128.0% difference, respectively; P <0.001). Excellent intraclass correlation coefficient agreement for net flow: 0.979, peak velocity: 0.931, and regurgitant fraction: 0.928. Conclusion: Our study demonstrates the potential of an efficient data analysis workflow to perform standardized 4D flow MRI processing in under 10 minutes and with good-to-excellent reproducibility for flow and velocity quantification in the thoracic aorta.