Highly accelerated free-breathing real-time 2D flow imaging using compressed sensing and shared velocity encoding.

OBJECTIVES: 2D real-time (RT) phase-contrast (PC) MRI is a promising alternative to conventional PC MRI, which overcomes problems due to irregular heartbeats or poor respiratory control. This study aims to evaluate a prototype compressed sensing (CS)-accelerated 2D RT-PC MRI technique with shared velocity encoding (SVE) for accurate beat-to-beat flow measurements. METHODS: The CS RT-PC technique was implemented using a single-shot fast RF-spoiled gradient echo with SVE by symmetric velocity encoding, and acquired with a temporal resolution of 51-56.5 ms in 1-5 heartbeats. Both aortic dissection phantom (n = 8) and volunteer (n = 7) studies were conducted using the prototype CS RT (CS, R = 8), the conventional (GRAPPA, R = 2), and the fully sampled PC sequences on a 3T clinical system. Flow parameters including peak velocity, peak flow rate, net flow rate, and maximum velocity were calculated to compare the performance between different methods using linear regression, intraclass correlation (ICC), and Bland-Altman analyses. RESULTS: Comparisons of the flow measurements at all locations in the phantoms demonstrated an excellent correlation (all R2 ≥ 0.93) and agreement (all ICC ≥ 0.97) with negligible means of differences. In healthy volunteers, a similarly good correlation (all R2 ≥ 0.80) and agreement (all ICC ≥ 0.90) were observed; however, CS RT slightly underestimated the maximum velocities and flow rates (~ 12%). CONCLUSION: The highly accelerated CS RT-PC technique is feasible for the evaluation of flow patterns without requiring breath-holding, and it allows for rapid flow assessment in patients with arrhythmia or poor breath-hold capacity. CLINICAL RELEVANCE STATEMENT: The free-breathing real-time flow MRI technique offers improved spatial and temporal resolutions, as well as the ability to image individual cardiac cycles, resulting in superior image quality compared to the conventional PC technique when imaging patients with arrhythmias, especially those with atrial fibrillation. KEY POINTS: • The highly accelerated prototype CS RT-PC MRI technique with improved temporal resolution by the concept of SVE is feasible for beat-to-beat flow evaluation without requiring breath-holding. • The results of the phantom and in vivo quantitative flow evaluation show the ability of the prototype CS RT-PC technique to obtain reliable flow measurements similarly to the conventional PC MRI. • With less than 12% underestimation, excellent agreements between the two techniques were shown for the measurements of peak velocities and flow rates.

Does Mental Distress Predict Cardiac Surgical Outcome?

BACKGROUND: Mental distress is suspected to influence the morbidity of cardiac patients. Evaluating mental distress in cardiac patients is rare and the impact on surgical outcome is still not certified. METHODS: In 94 cardiac surgical patients, mental distress was assessed by the Patient Health Questionnaire-4 (PHQ-4). We defined length of stay in hospital and on intensive care unit as well as time of mechanical ventilation as outcomes on surgery. Age, physical activity, diabetes, overweight, PHQ-4, and an inflammation marker were tested for their predictive value on outcomes. RESULTS: Reportedly prevalence of generalized anxiety was 16.0% and depression rate was 13.8%. Length of stay in hospital was 13 ± 8 days, time of mechanical ventilation was 10 (0-1,207) hours, and length of stay on intensive care unit was 3 ± 6 days. Length of stay in hospital was significantly predicted by age (p = 0.048), low physical activity (p = 0.029), and high C-reactive protein (CRP; p = 0.031). Furthermore, CRP was the only significant predictor of time of mechanical ventilation and length of stay on intensive care unit. CONCLUSION: Outcome was not predicted by mental distress. However, inflammation marker CRP was predictive for outcome, potentially caused by higher cardiovascular risk profile. Additionally, depression was referred to be associated with inflammation. Probably, the small sample and the timing of assessment were responsible for the missing relation between mental distress and outcome. We presume a relation with low physical activity and depression. Nevertheless, further randomized studies are needed to pay more attention on patients' distress to intervene preoperatively to improve postoperative outcome.

Role of CTA Surveillance for Management of Endovascular Repair of Aortic Dissection.

OBJECTIVES: The aim of this study was to evaluate the effect of timing for post-interventional CT imaging on the rate of re-intervention and all-cause mortality in patients with endovascular treatment of type B aortic dissections (TBAD). MATERIAL AND METHODS: Data on 70 patients with endovascular repair of aortic dissection during a three-year period from a single institution retrospectively were collected. Study participants were stratified based on those who had a postoperative CTA in the first 30 days after index intervention (early) vs. those who did not (late). The re-intervention and all-cause mortality rates between the two groups were investigated using Kaplan-Meier and Cox regression analysis. RESULTS: During a median follow-up time of 230 days, the primary endpoint (additional operation) was reached in 24/70 patients (34.3%) with no statistically significant difference between the early and late CTA group (log-rank-test: P = 0.886). All-cause mortality was present in 14/70 (20%) patients, with no statistically significant difference between both groups (log-rank-test: P = 0.440). Additionally, both groups had no significant differences in time to additional operation and death. Cox regression analysis revealed the presence of a chronic TBAD and underlying connective tissue disease as relevant risk factors for the need for an additional operation and obesity as a protective and renal failure as a negative factor for all-cause mortality. CONCLUSION: CTA surveillance within 30 days of the index operation did not significantly modify mortality or rate of re-intervention after endovascular treatment for TBAD. Surveillance recommendations should be tailored to individualized factors.

Feasibility of Coronary CT Angiography-derived Left Ventricular Long-Axis Shortening as an Early Marker of Ventricular Dysfunction in Transcatheter Aortic Valve Replacement.

Purpose: To evaluate the value of using left ventricular (LV) long-axis shortening (LAS) derived from coronary CT angiography (CCTA) to predict mortality in patients with severe aortic stenosis (AS) undergoing transcatheter aortic valve replacement (TAVR). Materials and Methods: Patients with severe AS who underwent CCTA for preprocedural TAVR planning between September 2014 and December 2019 were included in this retrospective study. CCTA covered the whole cardiac cycle in 10% increments. Image series reconstructed at end systole and end diastole were used to measure LV-LAS. All-cause mortality within 24 months of follow-up after TAVR was recorded. Cox regression analysis was performed, and hazard ratios (HRs) are presented with 95% CIs. The C index was used to evaluate model performance, and the likelihood ratio χ2 test was performed to compare nested models. Results: The study included 175 patients (median age, 79 years [IQR, 73-85 years]; 92 men). The mortality rate was 22% (38 of 175). When adjusting for predictive clinical confounders, it was found that LV-LAS could be used independently to predict mortality (adjusted HR, 2.83 [95% CI: 1.13, 7.07]; P = .03). In another model using the Society of Thoracic Surgeons Predicted Risk of Mortality (STS-PROM), LV-LAS remained significant (adjusted HR, 3.38 [95 CI: 1.48, 7.72]; P = .004), and its use improved the predictive value of the STS-PROM, increasing the STS-PROM C index from 0.64 to 0.71 (χ2 = 29.9 vs 19.7, P = .001). In a subanalysis of patients with a normal LV ejection fraction (LVEF), the significance of LV-LAS persisted (adjusted HR, 3.98 [95 CI: 1.56, 10.17]; P = .004). Conclusion: LV-LAS can be used independently to predict mortality in patients undergoing TAVR, including those with a normal LVEF.Keywords: CT Angiography, Transcatheter Aortic Valve Implantation/Replacement (TAVI/TAVR), Cardiac, Outcomes Analysis, Cardiomyopathies, Left Ventricle, Aortic Valve Supplemental material is available for this article. © RSNA, 2022See also the commentary by Everett and Leipsic in this issue.

Computed tomographic assessment of right ventricular long axis strain for prognosis after transcatheter aortic valve replacement.

OBJECTIVES: To investigate the predictive value of right ventricular long axis strain (RV-LAS) derived by cardiac computed tomography angiography (CCTA) for mortality in patients with aortic stenosis (AS) undergoing transcatheter aortic valve replacement (TAVR). METHODS: We retrospectively included patients with severe AS undergoing TAVR (n = 168, median 79 years). Parameters of RV function including RV-LAS and RV ejection fraction (RVEF) were assessed using pre-procedural systolic and diastolic CCTA series. The tricuspid annulus diameter (TAD) and diameter of the main pulmonary artery (mPA) were also assessed. All-cause mortality was recorded post-TAVR. Cox regression was used and results are presented with hazard ratio (HR) and 95% confidence interval (CI). Harrell's c-index was used to assess the performance of different models and the likelihood ratio test was used to compare nested models. RESULTS: Thirty-eight deaths (22.6%) occurred over a median follow-up of 21 months. RV-LAS > -11.42% (HR 2.86, 95% CI 1.44-5.67, p = 0.003), LVEF (HR 0.98, 95% CI 0.96-0.996; p = 0.02), TAD (HR 1.05, 95% CI 1.01-1.10, p = 0.02) and mPA diameter (HR 1.09, 95% CI 1.02-1.16, p = 0.01) were associated with mortality on univariable analysis. In a multivariable model, only RV-LAS (HR 2.36, 95% CI 1.04-5.36, p = 0.04) remained as an independent predictor of all-cause mortality. RV-LAS significantly improved the predictive power of the Society of Thoracic Surgeons Predicted Risk of Mortality (STS-PROM) (c-index 0.700 vs 0.637; p = 0.01). CONCLUSION: RV-LAS was an independent predictor of all-cause mortality in patients with severe AS undergoing TAVR, outperformed anatomical markers such as TAD and mPA diameter, and could potentially improve the current risk-stratifying tool.

The impact of gender bias in cardiothoracic surgery in Europe: a European Society of Thoracic Surgeons and European Association for Cardio-Thoracic Surgery survey.

OBJECTIVES: The European Society of Thoracic Surgeons and the European Association for Cardio-Thoracic Surgery designed a questionnaire to assess the impact of gender bias on a cardiothoracic surgery career. METHODS: A 46-item survey investigating gender bias was designed using online survey software from December 2020 to January 2021. All European Society of Thoracic Surgeons and European Association for Cardio-Thoracic Surgery members and non-members included in the mailing lists were invited to complete an electronic survey. Descriptive statistics and a comparison between gender groups were performed. RESULTS: Our overall response rate was 11.5% (1118/9764), of which 36.14% were women and 63.69% were men. Women were more likely to be younger than men (P < 0.0001). A total of 66% of the women reported having no children compared to only 19% of the men (P < 0.0001). Only 6% of women vs 22% of men were professors. More women (72%) also reported never having been a formal mentor themselves compared to men (38%, P < 0.0001). A total of 35% of female respondents considered leaving surgery because of episodes of discrimination compared to 13% of men; 67% of women said that they experienced being unfairly treated due to gender discrimination. Of the male surgeons, 31% reported that they were very satisfied with their career compared to only 17% of women (P < 0.0001). CONCLUSIONS: Women in cardiothoracic surgery reported significantly high rates of experiences with bias that may prevent qualified women from advancing to positions of leadership. Efforts to mitigate bias and support the professional development of women are at the centre of newly formed European committees.

Utility of Functional and Volumetric Left Atrial Parameters Derived From Preprocedural Cardiac CTA in Predicting Mortality After Transcatheter Aortic Valve Replacement.

BACKGROUND. Cardiac CTA is required for preprocedural workup before transcatheter aortic valve replacement (TAVR) and can be used to assess functional parameters of the left atrium (LA). OBJECTIVE. We aimed to evaluate the utility of functional and volumetric LA parameters derived from cardiac CTA to predict mortality in patients with severe aortic stenosis (AS) undergoing TAVR. METHODS. This retrospective study included 175 patients with severe AS (92 men, 83 women; median age, 79.0 years) who underwent cardiac CTA for clinical pre-TAVR assessment. A postdoctoral research fellow calculated maximum and minimum LA volumes using biplane area-length measurements; these values were indexed to body surface area, and maximum and minimum LA volume index (LAVImax and LAVImin, respectively) values were calculated. The LA emptying fraction (LAEF) was automatically calculated. All-cause mortality within a 24-month follow-up period after TAVR was recorded. To identify parameters predictive of mortality, Cox regression analysis was performed, and results were summarized by hazard ratio (HR) and 95% CI. The Harrell C-index was used to assess model performance. A radiology resident repeated the measurements in a random sample of 20% (n = 35) of the cases, and interobserver agreement was computed using the intraclass correlation coefficient (ICC). RESULTS. Thirty-eight deaths (21.7%) were recorded within a median follow-up of 21 months. LAVImax (HR, 1.02 [95% CI, 1.01-1.04]; p = .01), LAVImin (HR, 1.02 [95% CI, 1.01-1.04]; p < .001), and LAEF (HR, 0.97 [95% CI, 0.95-0.99]; p = .002) were predictive of mortality in univariable analysis. After adjusting for clinical parameters, only LAEF (HR, 0.97 [95% CI, 0.94-0.99]; p = .02) independently predicted mortality. The C-index of the Society of Thoracic Surgeons Predicted Risk of Mortality (STS-PROM) significantly increased from 0.636 to 0.683, 0.694, and 0.700 when incorporating into the model LAVImax, LAVImin, and LAEF, respectively. The ICC for maximum and minimum LA volumes and LAEF ranged from 0.94 to 0.99. CONCLUSION. LAEF derived from preprocedural cardiac CTA independently predicts mortality in patients with severe AS undergoing TAVR. CLINICAL IMPACT. Cardiac CTA-derived LA function, evaluated during pre-TAVR workup, can be used to assess preprocedural risk and may improve risk stratification in post-TAVR surveillance.

Right/Left Ventricular Blood Pool T2 Ratio as an Innovative Cardiac MRI Screening Tool for the Identification of Left-to-Right Shunts in Patients With Right Ventricular Disease.

BACKGROUND: Left-to-right (L-R) shunts are characterized by a pathological connection between high- and low-pressure systems, leading to a mixing of oxygen-rich blood with low oxygenated blood. They are typically diagnosed by phase-contrast cardiac magnetic resonance imaging (MRI) which requires extensive planning. T2 is sensitive to blood oxygenation and may be able to detect oxygenation differences between the left (LV) and right ventricles (RV) caused by L-R shunts. PURPOSE: To test the feasibility of routine T2 mapping to detect L-R shunts. STUDY TYPE: Retrospective. POPULATION: Patients with known L-R shunts (N = 27), patients with RV disease without L-R shunts (N = 21), and healthy volunteers (HV; N = 52). FIELD STRENGTH/SEQUENCE: 1.5 and 3 T/balanced steady-state free-precession (bSSFP) sequence (cine imaging), T2-prepared bSSFP sequence (T2 mapping), and velocity sensitized gradient echo sequence (phase-contrast MRI). ASSESSMENT: Aortic (Qs) and pulmonary (Qp) flow was measured by phase-contrast imaging, and the Qp/Qs ratio was calculated as a measure of shunt severity. T2 maps were used to measure T2 in the RV and LV and the RV/LV T2 ratio was calculated. Cine imaging was used to calculate RV end-diastolic volume index (RV-EDVi). STATISTICAL TESTS: Wilcoxon test, paired t-tests, Spearmen correlation coefficient, receiver operating curve (ROC) analysis. Significance level P < 0.05. RESULTS: The Qp/Qs and T2 ratios in L-R shunt patients (1.84 ± 0.84 and 0.89 ± 0.07) were significantly higher compared to those in patients with RV disease (1.01 ± 0.03 and 0.72 ± 0.10) and in HV (1.04 ± 0.04 and 0.71 ± 0.09). A T2 ratio of >0.78 showed a sensitivity, specificity, and negative predictive value of 100%, 73.9%, and 100%, respectively, for the detection of L-R shunts. The T2 ratio was strongly correlated with the severity of the shunt (r = 0.83). DATA CONCLUSION: RV/LV T2 ratio is an imaging biomarker that may be able to detect or rule-out L-R shunts. Such a diagnostic tool may prevent unnecessary phase-contrast acquisitions in cases with RV dilatation of unknown etiology. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY: Stage 2.

Short- and long-term outcomes for the surgical treatment of acute pulmonary embolism.

OBJECTIVES: Acute pulmonary embolism can be a life-threatening condition with a high mortality. The treatment choice is a matter of debate. The early and late outcomes of patients treated with surgical pulmonary embolectomy for acute pulmonary embolism in a single center were analyzed. METHODS: All consecutive patients operated on for pulmonary embolism between January 2002 and March 2017 were reviewed. Patient demographics and pre- and postoperative clinical data were retrieved from our patient registry, and risk factors for in-hospital and long-term mortality were identified. RESULTS: In total, 175 patients (mean age 59±3 years, 50% male) were operated on for acute pulmonary embolism. In-hospital mortality was 19% (34/175). No differences were found when comparing surgery utilizing a beating heart or cardioplegic arrest. Risk factors for in-hospital mortality were age >70 years [odds ratio (OR) 4.8, confidence interval (CI) 1.7-13.1, p=0.002], body surface area <2 m2 (OR 4.7, CI 1.6-13.7, p=0.004), preoperative resuscitation (OR 14.1, CI 4.9-40.8, p<0.001), and the absence of deep vein thrombosis (OR 9.6, CI 2.5-37.6, p<0.001). Follow-up was 100% complete with a 10-year survival rate of 66.4% in 141/175 patients surviving to discharge. Once discharged from hospital, none of the risk factors identified for in-hospital mortality were relevant for long-term survival except the absence of deep vein thrombosis (OR 3.2, CI 1.2-8.2, p=0.019). The presence of malignancy was a relevant risk factor for long-term mortality (OR 4.3, CI 1.8-10.3, p=0.001). CONCLUSION: Surgical pulmonary embolectomy as a therapy for acute pulmonary embolism demonstrates excellent short- and long-term results in patients with an otherwise life-threatening disease, especially in younger patients with a body surface area >2 m2 and pulmonary embolism caused by deep vein thrombosis. Pulmonary embolectomy should therefore not be reserved as a treatment of last resort for clinically desperate circumstances.

Multidetector Computed Tomography Angiography (MD-CTA) of Coronary Artery Bypass Grafts - Update 2017.

BACKGROUND: Coronary artery bypass grafting (CABG) is still an important therapeutic approach in the treatment especially of advanced coronary artery disease. In this study, we elucidate the current role of multidetector computed tomography angiography (MD-CTA) in imaging patients after CABG surgery. METHOD: This study is based on recent reports in the literature (2007 - 2016) on imaging of CABG using 64-slice MD-CT scanners and beyond. We included 13 reports that compared ECG-gated MD-CTA with conventional invasive coronary angiography (ICA) as the reference standard for the assessment of graft patency and for the detection of > 50 % stenoses. These studies had to provide absolute values for true-positive, true-negative, false-positive and false-negative results or at least allow calculation of these numbers. In total, 1002 patients with 2521 bypass grafts were the basis for this review. RESULTS AND CONCLUSION: The sensitivity and specificity for the assessment of graft patency or the detection of > 50 % graft stenosis were 97.2 % and 97.5 %, respectively. The negative and positive predictive values were 93.6 % and 99 %, respectively. By using prospective ECG-gating and an increasing pitch factor, the radiation dose exposure declined to 2.4 mSv in the latest reports. ECG-gated MD-CTA provides a fast and reliable, noninvasive method for assessing patients after CABG. The most substantial benefit of the newest CT scanner generations is a remarkable reduction of radiation dose exposure while maintaining a still excellent diagnostic accuracy during recent years. KEY POINTS: · MD-CTA using 64-slice MDCT scanners and beyond is a reliable, noninvasive method for evaluating CABGs.. · Technical advances such as prospective ECG-gating, iterative reconstruction algorithms and high-pitch scanning lead to a remarkable drop-down in radiation dose exposures as low as 2.4 mSv.. · Despite significant dose reductions, MD-CTA could maintain a high diagnostic accuracy in evaluating CABGs in recent years.. CITATION FORMAT: · Jungmann F, Emrich T, Mildenberger P et al. Multidetector Computed Tomography Angiography (MD-CTA) of Coronary Artery Bypass Grafts - Update 2017. Fortschr Röntgenstr 2018; 190: 237 - 249.

Septic cardiomyopathy: evidence for a reduced force-generating capacity of human atrial myocardium in acute infective endocarditis.

BACKGROUND: This study analyzes the myocardial force-generating capacity in infective endocarditis (IE) using an experimental model of isolated human atrial myocardium. In vivo, it is difficult to decide whether or not alterations in myocardial contractile behavior are due to secondary effects associated with infection such as an altered heart rate, alterations of preload and afterload resulting from valvular defects, and altered humoral processes. Our in vitro model using isolated human myocardium, in contrast, guarantees exactly defined experimental conditions with respect to preload, afterload, and contraction frequency, thus not only preventing confounding by in vivo determinants of contractility but also excluding effects of other factors associated with sepsis, hemodynamics, humoral influences, temperature, and medical treatment. METHODS: We analyzed right atrial trabeculae (diameter 0.3-0.5 mm, initial length 5 mm) from 32 patients undergoing aortic and/or mitral valve replacement for acute valve incompetence caused by IE and 65 controls receiving aortic and/or mitral valve replacement for nonendocarditic valve incompetence. Isometric force amplitudes and passive resting force values measured at optimal length in the two groups were compared using Student's t-test. RESULTS: There were no significant differences between the groups in terms of the passive resting force. The isometric force amplitude in the endocarditis group, however, was significantly lower than in the nonendocarditis group (p=0.001). In the endocarditis group, the calculated active force, defined as the isometric force amplitude minus the resting force, was significantly lower (p<0.0001) and the resting force/active force ratio was significantly higher (p<0.0001). Using linear regression to describe the function between resting force and active force, we identified a significant difference in slope (p<0.0001), with lower values found in the endocarditis group. CONCLUSION: Our data suggest that the force-generating capacity of atrial myocardium is significantly reduced in patients with IE. In these patients, an elevated resting force is required to achieve a given force amplitude. It remains unclear, however, whether this is due to calcium desensitization of the contractile apparatus, presence of myocardial edema, fibrotic remodeling, disruption of contractile units, or other mechanisms.