Incremental Utility of First-Pass Perfusion CMR for Prognostic Risk Stratification of Cancer-Associated Cardiac Masses.

BACKGROUND: Cardiac magnetic resonance (CMR) differentiates cardiac metastasis (CMET) and cardiac thrombus (CTHR) based on tissue characteristics stemming from vascularity on late gadolinium enhancement (LGE). Perfusion CMR can assess magnitude of vascularity; utility for cardiac masses (CMASS) is unknown. OBJECTIVES: This study sought to determine if perfusion CMR provides diagnostic and prognostic utility for CMASS beyond binary differentiation of CMET and CTHR. METHODS: The population comprised adult cancer patients with CMASS on CMR; CMET and CTHR were defined using LGE-CMR: CMASS+ patients were matched to CMASS- control subjects for cancer type/stage. First-pass perfusion CMR was interpreted visually and semiquantitatively for CMASS vascularity, including contrast enhancement ratio (CER) (plateau vs baseline) and contrast uptake rate (CUR) (slope). Follow-up was performed for all-cause mortality. RESULTS: A total of 462 cancer patients were studied, including patients with (CMET = 173, CTHR = 69) and without CMASS on LGE-CMR. On perfusion CMR, CER and CUR were higher within CMET vs CTHR (P < 0.001); CUR yielded better performance (AUC: 0.89-0.93) than CER (AUC: 0.66-0.72) (both P < 0.001) to differentiate LGE-CMR-evidenced CMET and CTHR, although both CUR (P = 0.10) and CER (P = 0.01) typically misclassified CMET with minimal enhancement. During follow-up, mortality among CMET patients was high but variable; 47% of patients were alive 1 year post-CMR. Patients with semiquantitative perfusion CMR-evidenced CMET had higher mortality than control subjects (HR: 1.42 [95% CI: 1.06-1.90]; P = 0.02), paralleling visual perfusion CMR (HR: 1.47 [95% CI: 1.12-1.94]; P = 0.006) and LGE-CMR (HR: 1.52 [95% CI: 1.16-2.00]; P = 0.003). Among patients with CMET on LGE-CMR, mortality was highest among patients (P = 0.002) with lesions in the bottom perfusion (CER) tertile, corresponding to low vascularity. Among CMET and cancer-matched control subjects, mortality was equivalent (P = NS) among patients with lesions in the upper CER tertile (corresponding to higher lesion vascularity). Conversely, patients with CMET in the middle (P = 0.03) and lowest (lowest vascularity) (P = 0.001) CER tertiles had increased mortality. CONCLUSIONS: Perfusion CMR yields prognostic utility that complements LGE-CMR: Among cancer patients with LGE-CMR defined CMET, mortality increases in proportion to magnitude of lesion hypoperfusion.

Institutional experience report on the target contouring workflow in the radiotherapy department for stereotactic arrhythmia radioablation delivered on conventional linear accelerators.

PURPOSE: In stereotactic arrhythmia radioablation (STAR), the target is defined using multiple imaging studies and a multidisciplinary team consisting of electrophysiologist, cardiologist, cardiac radiologist, and radiation oncologist collaborate to identify the target and delineate it on the imaging studies of interest. This report describes the workflow employed in our radiotherapy department to transfer the target identified based on electrophysiology and cardiology imaging to the treatment planning image set. METHODS: The radiotherapy team was presented with an initial target in cardiac axes orientation, contoured on a wideband late gadolinium-enhanced (WB-LGE) cardiac magnetic resonance (CMR) study, which was subsequently transferred to the computed tomography (CT) scan used for treatment planning-i.e., the average intensity projection (AIP) image set derived from a 4D CT-via an axial CMR image set, using rigid image registration focused on the target area. The cardiac and the respiratory motion of the target were resolved using ciné-CMR and 4D CT imaging studies, respectively. RESULTS: The workflow was carried out for 6 patients and resulted in an internal target defined in standard anatomical orientation that encompassed the cardiac and the respiratory motion of the initial target. CONCLUSION: An image registration-based workflow was implemented to render the STAR target on the planning image set in a consistent manner, using commercial software traditionally available for radiation therapy.

Massive Mysteries.

Papillary fibroelastomas are benign masses often originating from the endocardium of the aortic and mitral valves. Rarely, these neoplasms are found in areas of the heart embryonically distinct from the aortic and mitral valves. Diagnosis of a papillary fibroelastoma relies on multimodal imaging as well as histologic assessment. A case series of papillary fibroelastomas in unusual locations is presented, highlighting the role of multimodal imaging techniques in identifying these intra-cardiac masses. Differential diagnoses, imaging characteristics, histopathology, and preferred management strategies for cardiac masses are reviewed. The unique imaging qualities of cardiac masses are discussed.

Right Atrial Compression From Biodebris Associated With Long-Term Left Ventricular Assist Device Support.

Biodebris surrounding HVAD (Medtronic) intrapericardial centrifugal-flow left ventricular assist device outflow cannulas is common and appears to accumulate over time. We recently encountered 2 patients on long-term HVAD support with right atrial compression from such biodebris, prompting a review of our institution's HVAD cohort to better understand this phenomenon. (Level of Difficulty: Intermediate.).

Case report: paradoxically reversible perfusion defects on vasodilator stress imaging in a case of metastatic coronary compression.

Background: Patients with malignancy who experience metastasis to cardiac structures may exhibit ST-segment elevations and acute coronary syndrome (ACS) through poorly understood pathophysiologic mechanisms. We present a case in which vasodilator stress cardiovascular magnetic resonance provides unique insight into one such patient who suffered from recurrent episodes resembling ACS. Case summary: A 58-year-old male with metastatic lung adenocarcinoma presented with refractory angina and dynamic inferior electrocardiogram changes. The patient was referred for adenosine stress cardiovascular magnetic resonance, revealing multiple territories of abnormal perfusion during rest with improvement during adenosine infusion. Subsequent computed tomography displayed tumour encasement of the right coronary artery. Taken together, vasodilator-responsive extrinsic compression of multiple epicardial coronary arteries was suspected. Outpatient oncology follow-up for chemoimmunotherapy initiation was arranged with the hope that reducing tumour burden might alleviate coronary compression. However, in the ensuing months, the patient's disease advanced beyond the point of which his symptoms could be controlled medically, and he was ultimately enrolled in hospice care. Discussion: Encasement of coronary arteries can result in anginal symptoms if their position impairs coronary arterial flow. The presented case highlights the unique manner in which these lesions might behave on stress cardiac magnetic resonance imaging. Clinicians who encounter such unusual findings on vasodilator stress imaging should consider metastatic lesions to the cardiac structures on the differential diagnosis.

Cardiac MRI of Hereditary Cardiomyopathy.

Hereditary cardiomyopathy comprises a heterogeneous group of diseases of the cardiac muscle that are characterized by the presence of genetic mutations. Cardiac MRI is central to evaluation of patients with cardiomyopathy owing to its ability to allow evaluation of many different tissue properties in a single examination. For example, cine MRI is the standard of care for assessment of myocardial structure and function. It clearly shows regions of asymmetric wall thickening that are typical of hypertrophic cardiomyopathy and allows it to be differentiated from other hereditary disorders such as Fabry disease or transthyretin cardiac amyloidosis that produce concentric hypertrophy. Late gadolinium enhancement provides a different tissue property and allows these latter two causes of concentric hypertrophy to be distinguished on the basis of their enhancement appearances (Fabry disease shows midwall basal inferolateral enhancement, and amyloidosis shows global subendocardial enhancement). Native T1 mapping may similarly allow differentiation between Fabry disease and amyloidosis without the use of contrast material. T2*-weighted MRI is important in the detection and quantification of iron overload cardiomyopathy. Other hereditary entities for which comprehensive MRI has proven essential include Danon disease, familial dilated cardiomyopathy, hereditary muscular dystrophy, arrhythmogenic right ventricular cardiomyopathy, and ventricular noncompaction. As a result of the diagnostic power of cardiac MRI, cardiac MRI examinations are being requested with increasing frequency, not only in academic centers but also in community practices. The genetic background, pathophysiologic characteristics, and clinical presentation of patients with hereditary cardiomyopathy are described; the characteristic cardiac MRI features of hereditary cardiomyopathy are discussed; and the role of MRI in risk stratification, treatment, and prognostication in patients with cardiomyopathy is reviewed. ©RSNA, 2022 Online supplemental material is available for this article.

Influence of extracellular volume fraction on peak exercise oxygen pulse following thoracic radiotherapy.

BACKGROUND: Radiation-induced myocardial fibrosis increases heart failure (HF) risk and is associated with a restrictive cardiomyopathy phenotype. The myocardial extracellular volume fraction (ECVF) using contrast-enhanced cardiac magnetic resonance (CMR) quantifies the extent of fibrosis which, in severe cases, results in a noncompliant left ventricle (LV) with an inability to augment exercise stroke volume (SV). The peak exercise oxygen pulse (O2Pulse), a noninvasive surrogate for exercise SV, may provide mechanistic insight into cardiac reserve. The relationship between LV ECVF and O2Pulse following thoracic radiotherapy has not been explored. METHODS: Patients who underwent thoracic radiotherapy for chest malignancies with significant incidental heart dose (≥5 Gray (Gy), ≥10% heart) without a pre-cancer treatment history of HF underwent cardiopulmonary exercise testing to determine O2Pulse, contrast-enhanced CMR, and N-terminal pro-brain natriuretic peptide (NTproBNP) measurement. Multivariable-analyses were performed to identify factors associated with O2Pulse normalized for age/gender/anthropometrics. RESULTS: Thirty patients (median [IQR] age 63 [57-67] years, 18 [60%] female, 2.0 [0.6-3.8] years post-radiotherapy) were included. The peak VO2 was 1376 [1057-1552] mL·min- 1, peak HR = 150 [122-164] bpm, resulting in an O2Pulse of 9.2 [7.5-10.7] mL/beat or 82 (66-96) % of predicted. The ECVF, LV ejection fraction, heart volume receiving ≥10 Gy, and NTproBNP were independently associated with %O2Pulse (P < .001). CONCLUSIONS: In patients with prior radiotherapy heart exposure, %-predicted O2Pulse is inversely associated markers of diffuse fibrosis (ECVF), ventricular wall stress (NTproBNP), radiotherapy heart dose, and positively related to LV function. Increased LV ECVF may reflect a potential etiology of impaired LV SV reserve in patients receiving thoracic radiotherapy for chest malignancies.

Evidence-based cardiovascular magnetic resonance cost-effectiveness calculator for the detection of significant coronary artery disease.

BACKGROUND: Although prior reports have evaluated the clinical and cost impacts of cardiovascular magnetic resonance (CMR) for low-to-intermediate-risk patients with suspected significant coronary artery disease (CAD), the cost-effectiveness of CMR compared to relevant comparators remains poorly understood. We aimed to summarize the cost-effectiveness literature on CMR for CAD and create a cost-effectiveness calculator, useable worldwide, to approximate the cost-per-quality-adjusted-life-year (QALY) of CMR and relevant comparators with context-specific patient-level and system-level inputs. METHODS: We searched the Tufts Cost-Effectiveness Analysis Registry and PubMed for cost-per-QALY or cost-per-life-year-saved studies of CMR to detect significant CAD. We also developed a linear regression meta-model (CMR Cost-Effectiveness Calculator) based on a larger CMR cost-effectiveness simulation model that can approximate CMR lifetime discount cost, QALY, and cost effectiveness compared to relevant comparators [such as single-photon emission computed tomography (SPECT), coronary computed tomography angiography (CCTA)] or invasive coronary angiography. RESULTS: CMR was cost-effective for evaluation of significant CAD (either health-improving and cost saving or having a cost-per-QALY or cost-per-life-year result lower than the cost-effectiveness threshold) versus its relevant comparator in 10 out of 15 studies, with 3 studies reporting uncertain cost effectiveness, and 2 studies showing CCTA was optimal. Our cost-effectiveness calculator showed that CCTA was not cost-effective in the US compared to CMR when the most recent publications on imaging performance were included in the model. CONCLUSIONS: Based on current world-wide evidence in the literature, CMR usually represents a cost-effective option compared to relevant comparators to assess for significant CAD.

Cardiovascular magnetic resonance imaging in suspected cardiac tumour: a multicentre outcomes study.

AIMS: Cardiovascular magnetic resonance (CMR) imaging is a key diagnostic tool for the evaluation of patients with suspected cardiac tumours. Patient management is guided by the CMR diagnosis, including no further testing if a mass is excluded or if only a pseudomass is found. However, there are no outcomes studies validating this approach. METHODS AND RESULTS: In this multicentre study of patients undergoing clinical CMR for suspected cardiac tumour, CMR diagnoses were assigned as no mass, pseudomass, thrombus, benign tumour, or malignant tumour. A final diagnosis was determined after follow-up using all available data. The primary endpoint was all-cause mortality. Among 903 patients, the CMR diagnosis was no mass in 25%, pseudomass in 16%, thrombus in 16%, benign tumour in 17%, and malignant tumour in 23%. Over a median of 4.9 years, 376 patients died. Compared with the final diagnosis, the CMR diagnosis was accurate in 98.4% of patients. Patients with CMR diagnoses of pseudomass and benign tumour had similar mortality to those with no mass, whereas those with malignant tumour [hazard ratio (HR) 3.31 (2.40-4.57)] and thrombus [HR 1.46 (1.00-2.11)] had greater mortality. The CMR diagnosis provided incremental prognostic value over clinical factors including left ventricular ejection fraction, coronary artery disease, and history of extracardiac malignancy (P < 0.001). CONCLUSION: In patients with suspected cardiac tumour, CMR has high diagnostic accuracy. Patients with CMR diagnoses of no mass, pseudomass, and benign tumour have similar long-term mortality. The CMR diagnosis is a powerful independent predictor of mortality incremental to clinical risk factors.

Intimal sarcoma of the pulmonary artery treated with neoadjuvant radiation prior to pulmonary artery resection and reconstruction.

Intimal sarcoma (IS) is a rare malignancy arising in the great vessels or heart, most commonly in the pulmonary artery, primarily treated with surgical intervention. We report a case of IS of the pulmonary artery diagnosed after an endarterectomy to remove a suspected pulmonary embolism. The tumor could not be entirely resected and showed interval growth at post-operative follow up. Neoadjuvant radiotherapy was then delivered to improve resectability. Imaging confirmed decreased tumor size, and a surgical resection with pulmonary artery reconstruction and right upper lobectomy was then successfully performed. Adjuvant gemcitabine and docetaxel was later initiated. Four months post-operatively, the patient is alive without disease recurrence. While prior reports in the literature document use of adjuvant chemotherapy and radiotherapy for treatment of IS of the pulmonary artery, no prior experience has documented utility of neoadjuvant radiotherapy for improvement of resectability. Our experience suggests that neoadjuvant radiation should be considered to improve resectability in cases of borderline resectable IS of the pulmonary artery.

An interventional approach to left ventricular assist device outflow graft obstruction.

BACKGROUND: LVADs provide life-sustaining treatment for patients with heart failure, but their complexity allows for complications. One complication, LVAD outflow graft obstruction, may be misdiagnosed as intraluminal thrombus, when more often it is extraluminal compression from biodebris accumulation. It can often be treated endovascularly with stenting. This case series describes diagnostic and procedural techniques for the treatment of left ventricular assist device (LVAD) outflow graft obstruction. METHODS: We present four patients with LVADs who developed LVAD outflow graft obstruction within the bend relief-covered segment. All were initially diagnosed with computed tomographic angiography (CTA). All underwent invasive evaluation with intravascular ultrasound (IVUS), then were treated with stenting. After misdiagnosing a twist, we developed the technique of balloon "graftoplasty" to ensure suitability for stent delivery in subsequent cases. RESULTS: All patients presented with low-flow alarms and symptoms of low output, and were diagnosed with outflow graft obstruction by CTA. In all four, IVUS confirmed an extraluminal etiology. Patient 1 was treated with stenting and had a good outcome. Patient 2's obstruction was from twisting, rather than biodebris accumulation, and had sub-optimal stent expansion and ultimately required surgery. Balloon "graftoplasty" was used in subsequent cases to ensure subsequent stent expansion. Patients 3 and 4 were successfully stented. All improved after treatment. CONCLUSIONS: In patients with LVAD outflow graft obstruction, IVUS can distinguish intraluminal thrombus from extraluminal compression. Balloon "graftoplasty" can ensure that the outflow graft will respond to stenting. Many cases of LVAD outflow graft obstruction should be amenable to endovascular treatment.

Cardiac MRI utilizing late gadolinium enhancement (LGE) and T1 mapping in the detection of radiation induced heart disease.

BACKGROUND AND PURPOSE: Radiotherapy has been associated with late dose-dependent cardiovascular toxicity. In this cross-sectional pilot study, radiation dose distributions were correlated with areas of localized and diffuse myocardial fibrosis as measured by novel cardiac MRI (CMR) sequences including late gadolinium enhancement (LGE) and T1 mapping with the goal to identify early markers of myocardial damage. MATERIALS AND METHODS: Twenty-eight patients with chest tumors including lung, breast, esophagus, and lymphoma underwent CMR per study protocol on average 46.4 months (range 1.7-344.5) after radiotherapy. Patients without pretreatment cardiac history were included if the volume of heart receiving 5 Gy or more was at least 10% (V5Gy ≥ 10%). The association of LGE with cardiac dosimetric factors, clinical factors (e.g., tumor type, smoking history, BMI), and T1 values was analyzed. RESULTS: Cardiac maximum (Dmax) and mean dose (Dmean) equivalent to doses delivered in 2 Gy fractions (EQD2) were on average 50.9 Gy (range 6.2-108.0) and 8.2 Gy (range 1.0-35.7), respectively, compared to 60.8 Gy (40.8-108.0) and 6.8 Gy (1.8-21.8) among the 9 patients with LGE. Doses were not different between patients with and without LGE (p = 0.16 and 0.56, respectively). The average T1 value of the left ventricle myocardium was 1009 ms (range 933-1117). No significant correlation was seen for heart Dmax and Dmean and T1 values (p = 0.14 and 0.58, respectively). In addition, no significant association between clinical factors and the development of LGE was identified. CONCLUSIONS: No relation between cardiac doses, the presence of LGE or T1 values was observed. Further study is needed to determine the benefit of CMR for detecting radiotherapy-related myocardial fibrosis.

Management of Acute and Recurrent Pericarditis: JACC State-of-the-Art Review.

Pericarditis refers to the inflammation of the pericardial layers, resulting from a variety of stimuli triggering a stereotyped immune response, and characterized by chest pain associated often with peculiar electrocardiographic changes and, at times, accompanied by pericardial effusion. Acute pericarditis is generally self-limited and not life-threatening; yet, it may cause significant short-term disability, be complicated by either a large pericardial effusion or tamponade, and carry a significant risk of recurrence. The mainstay of treatment of pericarditis is represented by anti-inflammatory drugs. Anti-inflammatory treatments vary, however, in both effectiveness and side-effect profile. The objective of this review is to summarize the up-to-date management of acute and recurrent pericarditis.

Determinants of Cardiorespiratory Fitness Following Thoracic Radiotherapy in Lung or Breast Cancer Survivors.

We measured peak oxygen consumption (VO2) in previous recipients of thoracic radiotherapy and assessed the determinants of cardiorespiratory fitness with an emphasis on cardiac and pulmonary function. Cancer survivors who have received thoracic radiotherapy with incidental cardiac involvement often experience impaired cardiorespiratory fitness, as measured by reduced peak VO2, a marker of impaired cardiovascular reserve. We enrolled 25 subjects 1.8 (0.1 to 8.2) years following completion of thoracic radiotherapy with significant heart exposure (at least 10% of heart volume receiving at least 5 Gray). All subjects underwent cardiopulmonary exercise testing, Doppler echocardiography, and circulating biomarkers assessment. The cohort included 16 Caucasians (64%), 15 women (60%) with a median age of 63 (59 to 66) years. The peak VO2 was 16.8 (13.5 to 21.9) ml·kg-1·min-1 or moderately reduced at 62% (50% to 93%) of predicted. The mean cardiac radiation dose was 5.4 (3.7 to 14.7) Gray, and it significantly correlated inversely with peak VO2 (R = -0.445, p = 0.02). Multivariate regression analysis revealed the diastolic functional reserve index and the N-terminal pro-brain natriuretic peptide (NTproBNP) serum levels were independent predictors of peak VO2 (ß = +0.813, p <0.01 and ß = -0.414, p = 0.04, respectively). In conclusion, patients who had received thoracic radiation display a dose-dependent relation between the cardiac radiation dose received and the impairment in peak VO2, the reduction in diastolic functional reserve index, and elevation of NTproBNP.

Left Ventricular Assist Device Outflow Graft Compression: Incidence, Clinical Associations and Potential Etiologies.

BACKGROUND: Left ventricular assist devices (LVADs) have revolutionized the treatment of advanced heart failure, but proliferation of device therapy has unmasked potential complications. Reports have emerged of outflow graft narrowing due to extrinsic compression. METHODS AND RESULTS: The records of patients with LVADs that had been implanted at our institution were reviewed. Those who had postimplantation computed tomography angiographies sufficient to analyze the outflow graft lumen were identified, and the studies were analyzed to characterize the outflow graft lumen. We identified 241 patients; 110 (46%) had suitable computed tomography angiographies. Of those, 15 (14%) had evidence of outflow graft lumen narrowing, all in HeartMate devices and all within the portion covered by the bend relief. Of the 15, 3 underwent invasive examination, all without intraluminal thrombus but, rather, with biodebris between the bend relief and the outflow graft. Patients with HeartWare devices had a wide range of biodebris accumulation surrounding the outflow graft but no cases of lumen narrowing. On multivariable analysis, 1) time from device implant to scan, 2) nonischemic cardiomyopathy and 3) age at implant were significantly associated with higher risk of graft narrowing. CONCLUSION: Outflow graft narrowing can be seen in a number of patients with HeartMate LVADs within the portion covered by the bend relief. In the limited number of patients who underwent invasive evaluation, the narrowing was found to arise from extrinsic compression rather than intraluminal thrombus. The clinical significance of this requires further investigation.

Late Gadolinium Enhancement Cardiac Magnetic Resonance Tissue Characterization for Cancer-Associated Cardiac Masses: Metabolic and Prognostic Manifestations in Relation to Whole-Body Positron Emission Tomography.

Background Cardiac magnetic resonance ( CMR) differentiates neoplasm from thrombus via contrast enhancement; positron emission tomography ( PET) assesses metabolism. The relationship between CMR contrast enhancement and metabolism on PET is unknown. Methods and Results The population included 121 cancer patients undergoing CMR and 18F-fluorodeoxyglucose (18F- FDG) - PET , including 66 with cardiac masses and cancer-matched controls. Cardiac mass etiology (neoplasm, thrombus) on CMR was defined by late gadolinium enhancement; PET was read blinded to CMR for diagnostic performance, then colocalized to measure FDG avidity. Of CMR -evidenced thrombi (all nonenhancing), none were detected by PET . For neoplasm, PET yielded reasonable sensitivity (70-83%) and specificity (75-88%). Lesions undetected by PET were more likely to be highly mobile ( P=0.001) despite similar size ( P=0.33). Among nonmobile neoplasms, PET sensitivity varied in relation to extent of CMR -evidenced avascularity; detection of diffusely enhancing or mixed lesions was higher versus predominantly avascular neoplasms (87% versus 63%). Colocalized analyses demonstrated 2- to 4-fold higher FDG uptake in neoplasm versus thrombus ( P<0.001); FDG uptake decreased stepwise when neoplasms were partitioned based on extent of avascularity on late gadolinium enhancement CMR ( P≤0.001). Among patients with neoplasm, signal-to-noise ratio on late gadolinium enhancement CMR moderately correlated with standardized uptake values on PET ( r=0.42-0.49, P<0.05). Mortality was higher among patients with CMR -evidenced neoplasm versus controls (hazard ratio: 1.99 [95% CI, 1.1-3.6]; P=0.03) despite nonsignificant differences when partitioned via FDG avidity (hazard ratio: 1.56 [95% CI, 0.85-2.74]; P=0.16). Among FDG-positive neoplasms detected concordantly with CMR , mortality risk versus cancer-matched controls was equivalently increased (hazard ratio: 2.12 [95% CI, 1.01-4.44]; P=0.047). Conclusions CMR contrast enhancement provides a criterion for neoplasm that parallels FDG -evidenced metabolic activity and stratifies prognosis. Extent of tissue avascularity on late gadolinium enhancement CMR affects cardiac mass identification by FDG - PET .